Neuroscience Flashcards
1
Q
Theta activity in frontal and temporal cortex, and gamma in occipital cortex are examples of….
- different frequencies of oscillation integrating activity across similar temporal scales.
2 different frequencies of oscillation integrating activity across different temporal scales.
- different frequencies of oscillation integrating activity across different spatial scales.
- different frequencies of oscillation integrating activity across similar spatial scales.
A
different frequencies of oscillation integrating activity across different spatial scale
2
Q
Cells in the medial entorhinal cortex that fire at regular spatial intervals as an animal navigates its environment are known as….
A
Grid Cells
3
Q
Cells in the hippocampus that fire when an animal enters a particular location in the environment are known as..
A
Place cells
4
Q
Afferent burst activity resulting in long-term potentiation if arriving on the excitatory phase of local theta rhythm, but not if arriving on the inhibitory phase is an example of….
- item integration/segregation.
- the importance of timing or co-incident activity in neural networks.
3 integration of different brain areas or different spatial scales. - spatial coding in a network.
A
the importance of timing or co-incident activity in neural networks.
5
Q
Gamma activity nested in the theta wave is believed to allow for….
excitation in local, and inhibition in global networks.
inhibition in local relative to global brain networks.
inhibition across global brain scales.
item integration and segregation.
A
item integration and segregation.
6
Q
Beta activity is often seen at the end of trials in particular tasks and is believed to be involved in….
A
a item or memory clear out
7
Q
Frontal midline theta with an orbital-frontal and with an anterior cingulate distribution occur respectively during…
recollection and familiarity versions of a recognition memory task.
familiarity and recollection versions of a recognition memory task.
allocentric and egocentric versions of a spatial memory task.
egocentric and allocentric versions of a spatial memory task.
A
familiarity and recollection versions of a recognition memory task.
8
Q
Two visual stimuli arriving within one alpha oscillatory cycle, versus stimuli arriving on different cycles will facilitate respectively….
item segregation versus item integration
item segregation versus item segmentation
item integration versus item segregation
item segmentation versus item segregation
A
item integration versus item segregation
9
Q
- A system for storing memories as different synaptic weights across a neural network is known as..
non-linear
distributed
linear
non-distributed
A
distributed
10
Q
In the human sensory LTP paradigm, the fact that only the “tetanised” orientation or spatial frequency of a stimulus is potentiated, is an demonstration of..
reversibility
associativity
specificity
generalisability
A
specificity
11
Q
It has been demonstrated that those carrying the met allele for the BDNF single nucleotide polymorphism (SNP)….
have significantly higher visual memory scores, and lower amplitude LTP.
have significantly lower visual memory scores, and lower amplitude LTP.
have significantly lower visual memory scores, and higher amplitude LTP.
have significantly higher visual memory scores, and higher amplitude LTP.
A
have significantly lower visual memory scores, and lower amplitude LTP.
12
Q
Normann et al., demonstrated that the antidepressant (and SSRI) Sertraline….
increased LTP.
decreased LTD.
increased LTD.
decreased LTP.
A
Increased LTP
13
Q
Human sensory LTP has been shown to be….
increased in schizophrenia and depression, and decreased in autism spectrum.
decreased in schizophrenia, depression and autism spectrum.
decreased in schizophrenia and depression, and increased in autism spectrum.
increased in schizophrenia, depression and autism spectrum.
A
decreased in schizophrenia and depression, and increased in autism spectrum.
14
Q
According to one model of depression, stress causes………
an increase of BDNF release, and LTD-like response at glutamatergic synapses.
a reduction of BDNF release, and an LTD-like response at glutamatergic synapses.
a reduction of BDNF release, and LTP-like response at glutamatergic synapses.
an increase of BDNF release, and an LTP-like response at glutamatergic synapses.
A
a reduction of BDNF release, and an LTD-like response at glutamatergic synapses.
15
Q
In a hippocampal model of Alzheimer’s _________________ has been shown to reduce LTP.
peanut butter (PB)
fibreloid alpha (FA)
amyloid beta (Aβ)
centroid theta (CT)
A
Amyloid Beta
16
Q
- According to Badzakova-Trajkov et al. (2009), the ACC and dlPFC are involved in respectively, …
attentional allocation and conflict detection.
conflict detection and motor selection.
motor inhibition and attentional selection.
conflict detection and motor inhibition.
A
attentional allocation and conflict detection.
17
Q
In the radial arm maze, when an animal can remember which arms have already been visited within a trial, this demonstrates…. memory
A
working memory
18
Q
Theories of working memory that assign different roles to the ventral and dorsal prefrontal cortices depending on the type of information being processed are known as…..
material specific theories.
process specific theories.
time specific theories.
space specific theories.
A
Material specific (specific to the type of material)
19
Q
Theories of working memory that assign different roles to the ventral and dorsal prefrontal cortices depending on the type of processing being performed are known as…..
time specific theories.
space specific theories.
process specific theories.
material specific theories.
A
what kind of PROCESSING = processing specific
20
Q
The ventromedial prefrontal cortex is believed to be particularly important for the………
spatial organisation of memories.
local/global organisation of memories.
temporal organisation of memories.
hierarchical organisation of memories.
A
temporal organisation of memories.
21
Q
Arising in the last 35-40 thousand years, anatomically modern humans (as distinct from more archaic humans) are sometimes referred to by archeologists as…..
homo sapiens superior
homo super sapiens
homo sapiens sapiens
the Bettermans
A
homo sapiens sapiens
22
Q
A species brain weight relative to body weight is known as the…..
encephalization quotient.
intelligence quotient.
, Not Selected
myelination quotient.
encephalization dividend.
A
encephalization quotient. EQ
23
Q
The fact that the foramen magnum points down in early some African hominin is usually taken as evidence against….
the fast train hypothesis.
the arboreal hypothesis.
the savannah hypothesis.
the slow boat hypothesis.
A
the savannah hypothesis.
24
Q
Select the appropriate options to best describe current beliefs about the cortical generators of the scalp electroencephalogram (EEG). Cortical pyramidal cells are arranged in an _______ field configuration, while non-pyramidal cells are in _______ field configurations. Consequently, neural potentials generated by _______ cells will tend to sum constructively, and are most likely to be the dominant contributor to the scalp EEG.
open; closed; pyramidal
closed; open; non-pyramidal
open; closed; non-pyramidal
closed; open; pyramidal
A
open; closed; pyramidal
25
Which neural membrane potentials are understood to be the main contributors to the scalp electroencephalogram (EEG)?
Postsynaptic potentials (EPSPs and IPSPs)
26
What role does signal averaging play in the derivation of event-related brain potentials (ERPs) from EEG data?
Summation of electrical fields. Signals generated by closed-field generators will be eliminated, while those generated by open-field generators will be amplified.
Filtering of the signal. Frequencies that are not related to the ERP will be eliminated.
Signal amplification. Potentials that are correlated with the timing of the event will sum, so that the ERP will be larger in amplitude as more trials are included.
Noise reduction. Potentials that are not correlated with the timing of the event will average destructively, revealing the ERP.
Noise reduction. Potentials that are not correlated with the timing of the event will average destructively, revealing the ERP.
Noise reduction. Potentials that are not correlated with the timing of the event will average destructively, revealing the ERP.
27
According to the study of cochlear implant users reported by Sandmann and colleagues (Sandmann, P., Dillier, N. et al., Brain, 2012, 135, 555-568), what mechanism best accounts for different patterns of visual evoked potentials (VEPs) between cochlear implant recipients and control participants with normal hearing?
Compensation. People who are profoundly deaf learn to rely more on other senses, resulting in amplified responses to visual stimulation.
Neural atrophy. The auditory cortex in people with profound deafness may begin to atrophy (or degenerate), resulting in lower VEP amplitudes.
Neural plasticity. The auditory cortex of at least some people with profound deafness begins to respond to visual stimuli, resulting in atypical VEPs.
Electrical interference. The electrical fields generated by the cochlear implants – particularly their batteries – may interfere with the brain’s electrical fields, resulting in distorted VEP signals.
Neural plasticity. The auditory cortex of at least some people with profound deafness begins to respond to visual stimuli, resulting in atypical VEPs.
28
Multiple sclerosis is a disease affecting the myelin sheaths that surround axons in nerves and cortical white matter. If a person has MS affecting their optic nerve, how would we expect VEPs to be altered?
The VEP would appear similar to one recorded from a person without MS, since the neurons would still generate action potentials.
The timing of the early VEP components would not be affected, but the N1 (or N150) and later components would be delayed.
The amplitudes of all VEP components would be reduced because fewer neurons are contributing to their generation.
The timing (or latency) of VEP components would be delayed because the action potentials would take longer to reach the visual cortex.
The timing (or latency) of VEP components would be delayed because the action potentials would take longer to reach the visual cortex.
29
In the context of event-related brain potentials (ERPs), what is the “inverse problem”?
It is not possible to determine precisely and unambiguously the location of the brain source of a particular ERP component.
30
According to a study by Schweinberger and Neumann (Schweinberger, S.R. & Neumann, M.F., Cortex, 2016, 80, 141-153), which face-related ERP component is typically larger in amplitude in response to the presentation of an “anti-caricature” than to the presentation of the true (“veridical”) face? "HEy its a face that matches my template"
P200
31
According to the 2012 study by Wronka and colleagues (Wronka, E., Kaiser, J., & Coenen, A.M.L., Acta Neurobiologica, 2012, 72, 51-64), which pair of statements best distinguishes between the P3a and P3b ERP components evoked during a “novelty oddball” paradigm?
P3a is evoked by both targets and task-irrelevant oddball stimuli; P3b is evoked by targets only.
32
According to the “Global Neuronal Workspace” theory of consciousness, which of the following statements best captures the distinction between “unconscious” and “conscious” processing of a sensory stimulus?
Stimulus-related activity that occurs before about 300 milliseconds from the onset of the stimulus is unconscious. Activity that occurs after about 300 milliseconds is conscious.
Stimulus-related activity in the modules of the temporal lobe is conscious. Activity in the modules of the parietal lobe remains unconscious.
Activity in the modules of the “processing network” is automatic and unconscious. Only when selected information is broadcast to the global neuronal workspace does it become conscious.
Activity in the subcortical sensory pathways is unconscious. Only when it reaches the hierarchically organized models of the cerebral cortex does it become conscious.
Activity in the modules of the “processing network” is automatic and unconscious. Only when selected information is broadcast to the global neuronal workspace does it become conscious.
33
According to the “Global Neuronal Workspace” theory of consciousness, which ERP component is the earliest reliable signature of conscious awareness of a visual stimulus?
P3a
P3b
P1 (P100)
VAN (Visual Awareness Negativity)
P3b
34
The “Global Neuronal Workspace” theory of consciousness (GNWT) implies that conscious awareness of a visual stimulus or even occurs in an “all-or-none” fashion – a stimulus either reaches consciousness or it doesn’t. A contrasting view is that consciousness arises earlier in processing than predicted by GNWT. According to this view, conscious awareness of a visual stimulus is reflected in which ERP component?
P3b
VAN (Visual Awareness Negativity)
P1 (P100)
P3a
VAN
35
The “Predictive Coding” theory holds that the brain generates predictions, or hypotheses about the world which are compared with sensory information. Mismatches between the prediction and the input are then used to refine and update the prediction. Which of the following ERP components can be interpreted as evidence for this theory?
Mismatch Negativity (MMN)
P300 (including both P3a and P3b)
N400
All of the above are consistent with predictive coding.
All
36
According to the “Predictive Coding” theory, why does an “oddball” stimulus (i.e., a stimulus that is rare or unexpected) generate a larger ERP response than an expected one?
The ERP reflects “prediction error,” or the discrepancy between predicted stimuli and those received.
37
Referring to ERP studies of memory encoding and retrieval, which statement best describes the “subsequent memory effect” (SME).
Stimuli that evoke a large P300/P3b during the retrieval phase of the experiment are likely to have been presented in a bold font during the training/encoding phase of the experiment.
Stimuli that evoke a P300/P3b during encoding are likely to be categorised as “new” during the retrieval phase of the experiment.
Stimuli that evoke a larger P300/P3b during the training/encoding phase of the experiment are more likely to be remembered during the retrieval phase of the experiment.
Stimuli that evoke a more frontal P3-like ERP are more likely to be subsequently recalled than those that evoke a more parietal P3b.
Stimuli that evoke a larger P300/P3b during the training/encoding phase of the experiment are more likely to be remembered during the retrieval phase of the experiment.
38
Libet’s famous 1983 experiment appeared to demonstrate that motor-system activity in the form of the Readiness Potential (RP) could be detected from the brain prior to a person forming the will to act (in this case, press a button). This finding has been widely interpreted as evidence against Free Will. Trevena and Miller (2002, 2010) offered a refutation of this claim. What was the basis for this refutation?
Trevena and Miller recorded the lateralized readiness potential (LRP) rather than the RP used by Libet. The LRP is more tightly associated with movement preparation and could only be detected after the person formed the will to act.
Trevena and Miller suggested that the sensory potentials evoked by touching the button contaminated the RP and made its onset appear earlier than it really was.
According to Trevena and Miller, the RP recorded in Libet’s experiment was likely overlapping with P3b activity generated when the person decided to press the button, so was not an accurate measure.
, Not Selected
Trevena and Miller critiqued Libet’s use of self-report as a measure of the moment the person became aware of the will to act.
Trevena and Miller recorded the lateralized readiness potential (LRP) rather than the RP used by Libet. The LRP is more tightly associated with movement preparation and could only be detected after the person formed the will to act.
39
In their study of event-related lateralisations evoked during a visual search task, which component did Hilimire and colleagues (2011) associate with the processing of target-like distractor stimuli?
SPCN
N2pc
LRP
Ptc
Ptc
40
1. Theta activity in frontal and temporal cortex, and gamma in occipital cortex are examples of....
different frequencies of oscillation integrating activity across similar temporal scales.
different frequencies of oscillation integrating activity across different temporal scales.
different frequencies of oscillation integrating activity across different spatial scales.
different frequencies of oscillation integrating activity across similar spatial scales.
different frequencies of oscillation integrating activity across different spatial scales.
41
Cells in the medial entorhinal cortex that fire at regular spatial intervals as an animal navigates its environment are known as....
grid cells
border cells
head direction cells
place cells
grid cells
42
Cells in the hippocampus that fire when an animal enters a particular location in the environment are known as..
head direction cells
border cells
grid cells
place cells
place cells
43
Afferent burst activity resulting in long-term potentiation if arriving on the excitatory phase of local theta rhythm, but not if arriving on the inhibitory phase is an example of....
item integration/segregation.
the importance of timing or co-incident activity in neural networks.
integration of different brain areas or different spatial scales.
spatial coding in a network.
the importance of timing or co-incident activity in neural networks.
44
Gamma activity nested in the theta wave is believed to allow for....
excitation in local, and inhibition in global networks.
inhibition in local relative to global brain networks.
inhibition across global brain scales.
item integration and segregation.
item integration and segregation.
45
Frontal midline theta with an orbital-frontal and with an anterior cingulate distribution occur respectively during….
recollection and familiarity versions of a recognition memory task.
familiarity and recollection versions of a recognition memory task.
allocentric and egocentric versions of a spatial memory task.
egocentric and allocentric versions of a spatial memory task.
familiarity and recollection versions of a recognition memory task.
46
In the lab demo of EEG, we placed three electrodes on the participant. One was a "ground" electrode that clipped to a sticker placed on the mastoid process behind one ear. There were two electrodes in the elastic headband. Why did these two electrodes only produce a single EEG trace?
We could have recorded an EEG signal from each of the electrodes in the headband, but chose to use only one for convenience.
The EEG setup we used allows us to record from either of the two headband electrodes, but not both at the same time.
The EEG that we recorded was the difference in voltage between the two electrodes in the headband.
We could have recorded three EEG signals, one from each of the three electrodes. but chose to use only one for convenience.
The EEG that we recorded was the difference in voltage between the two electrodes in the headband.
47
The figure above shows the power spectrum of EEG recorded in two conditions. In one, the participant was awake and alert with their eyes open (solid blue line). In the other condition, the participant was awake, but was resting with their eyes closed (asked red line). EEG power is plotted against Frequency in Hz. What phenomenon does this figure illustrate?
Both conditions have a peak in EEG power at about 10 Hz. This is probably an artefact generated by the mains power lines.
There is an increase in alpha power (roughly 8-12 Hz) in the eyes-closed condition relative to the eyes-open condition.
There is more overall power in the eyes-closed condition, indicating that the brain is more active when the eyes are closed than when they are open.
There is a greater power at about 10 Hz in the eyes-closed than eyes-open condition, probably due to rolling eye movements that occur when the eyes are closed.
There is an increase in alpha power (roughly 8-12 Hz) in the eyes-closed condition relative to the eyes-open condition.
48
Which of the following is the most serious impediment to the adoption of "brain fingerprinting" in the New Zealand criminal justice system?
The possibility of "false negatives" in which a guilty person is incorrectly found to have no guilty knowledge.
The high rate of "indeterminate" findings in the sample of parolees in the study by Afzali, Seren-Grace and colleagues implies that too many people are incorrectly classified.
The susceptibility of the technique to effective countermeasures that could lead to incorrect conclusions.
The possibility of "false positives", in which an innocent person is incorrectly found to possess guilty knowledge.
The possibility of "false positives", in which an innocent person is incorrectly found to possess guilty knowledge.
49
The "Brain Fingerprinting" technique relies upon measurement of the amplitude of the P300 component of the event-related brain potential (ERP). In the context of of P300-based brain fingerprinting, which of the following statements is true?
In order to create stable waveforms for each trial type (irrelevant, target, probe), a number of repetitions of each must be recorded and the EEG signals averaged to create an event-related potential (ERP).
The P300 evoked by guilty knowledge is large enough in amplitude that it can be observed reliably observed in response to a single presentation of a probe stimulus.
In a sample of university students, the P300 evoked by a "guilty knowledge" probe could be reliably observed in response to a single presentation (trial). However, in a sample of parolees with criminal backgrounds, this was not true and averaging had to be used to differentiate between probes, targets, and irrelevant stimuli.
In laboratory conditions, the P300 evoked by a "guilty knowledge" probe can be reliably observed in response to a single presentation (trial). However, in "real-world" contexts this is not true, and averaging must be used to differentiate between probes, targets, and irrelevant stimuli.
In order to create stable waveforms for each trial type (irrelevant, target, probe), a number of repetitions of each must be recorded and the EEG signals averaged to create an event-related potential (ERP).
50
Despite apparently outperforming traditional polygraphy, the "brain fingerprinting" technique has remained controversial, and has only been admitted as courtroom evidence a few times. The 2022 report published by Afzali, Seren-Grace and colleagues explored the potential use of EEG-based "brain fingerprinting" in Aotearoa New Zealand. Which of the following statements best reflects the conclusions of this report?
EEG-based brain fingerprinting is essentially "junk science" and should not be considered further.
EEG-based brain fingerprinting is a reliable laboratory that technique that should be deployed in high-profile cases in which guilt cannot otherwise be determined.
While a promising technique, EEG-based brain fingerprinting remains too unreliable to use in a legal context at this time.
EEG-based brain fingerprinting is an interesting idea that works on university students in a lab setting, but fails miserably when used to detect knowledge of real-world crimes.
While a promising technique, EEG-based brain fingerprinting remains too unreliable to use in a legal context at this time.
51
According to the "brain fingerprinting" method of detecting guilty knowledge of a crime (e.g., Farwell & Donchin, 1991), how can P300 amplitudes distinguish guilty people from innocent?
"Target" and "probe" stimuli should evoke P300 responses from everyone, but the P300 evoked by probes will be larger than that for targets in innocent people, and vice-versa for guilty.
"Probe" stimuli representing knowledge of a crime should not evoke any response from guilty people, but will evoke a P300 from innocent people.
"Probe" stimuli representing guilty knowledge should evoke a strong P300 from guilty, but not innocent people.
"Probe" stimuli representing guilty knowledge should evoke a P300 from guilty people, while "irrelevant" stimuli should evoke a P300 from innocent people.
"Probe" stimuli representing guilty knowledge should evoke a strong P300 from guilty, but not innocent people.
52
Wilson et al’s (2017) results with respect to LTP in ASD support the ________.
“Intense Flavour Theory” of Markram and Markram (2010)
“Small World Theory” of Markram and Markram (2010)
“Intense World Theory” of Markram and Markram (2010)
“Intense Music Theory” of Markram and Markram (2010)
“Intense World Theory” of Markram and Markram (2010)
53
Wilson et al. (2017) showed that, relative to controls, ________ in people on the autism spectrum.
LTP was enhanced
LTD was enhanced
LTD was reduced
LTP was reduced
LTP was enhanced
54
Norman et al (2007) showed that administration of an SSRI ________.
decreased the amplitude of LTP
increased the amplitude of LTP
increased the amplitude of LTD
decreased the amplitude of LTD
increased the amplitude of LTP
55
Norman et al (2007) showed that, relative to controls ________in people with depression.
LTP was enhanced
LTP was reduced
LTD was reduced
LTD was enhanced
LTP was reduced
56
Cavus et al (2012) showed that, relative to controls ________in people with schizophrenia.
LTP was enhanced
LTD was enhanced
LTP was reduced
LTD was reduced
LTP was reduced
57
von Stein and Sarthein (2000) suggest that there is an inverse relation between the spatial ________ of neural integration and the ________ of neural oscillations modulating the integration.
scale, amplitude
scale, phase
phase, amplitude
scale, frequency
scale, frequency
58
In experiments by Huerta and Lisman (1995), a stimulation burst at the ______ of theta induced ________, while the same burst at the _______ of theta induced ________of previously potentiated synapses.
peak, LTP, trough, depotentiation or LTD
trough, LTP, peak, LTP
trough, LTP, peak, LTD
peak, LTD, trough, LTP
peak, LTP, trough, depotentiation or LTD
59
In response to a comment by O'Keefe and Burgess (Trends Cog Sci 3 (1999)), Kahana et al. (1999) note that..
in humans, theta-range oscillations are only seen in navigation tasks, and are generated in a number of extra-hippocampal sites.
in humans, theta-range oscillations are seen in a variety of tasks, and are only generated in the hippocampus.
in humans, theta-range oscillations are seen in a variety of tasks, and are generated in a number of extra-hippocampal sites.
in humans, theta-range oscillations are only seen in navigation tasks, and are only generated in the hippocampus.
in humans, theta-range oscillations are seen in a variety of tasks, and are generated in a number of extra-hippocampal sites.
60
Kahana et al., Nature 399, 781–784 (1999) proposed that in humans _____________________ resulted in theta activity analogous to that seen in a rat hippocampus during exploration of its environment.
theta occurring during the Stroop task
theta occurring during a virtual navigation task
theta occurring during a working memory task
theta occurring during a recognition memory task
theta occurring during a virtual navigation task
61
Reverse inference is an invalid inference in fMRI research that involves
inferring mental states based solely on task-related fMRI activation maps
62
Running statistical tests on > 100 000 voxels is likely to produce many _____________, which can be minimised by _________________________
false positives, "smoothing" fMRI data
false negatives, "smoothing" fMRI data
false positives, correcting for multiple comparisons
false negatives, correcting for multiple comparisons
false positives, correcting for multiple comparisons
63
In MRI, application of a ____________ causes protons to _________ around a main magnetic field (called ___).
radio-frequency pulse, decay, B0
radio-frequency pulse, precess, B0
radioactive tracer, precess, B0
radio-frequency pulse, precess, B1
radio-frequency pulse, precess, B0
64
Standard task-related fMRI analyses are often described as ____________ because _________________________.
multivariate, BOLD signal is averaged across the entire brain
multivariate, univariate tests (e.g. a t-test) are performed at every voxel in the brain
massively univariate, BOLD signal is averaged across the entire brain
massively univariate, univariate tests (e.g. a t-test) are performed at every voxel in the brain
massively univariate, univariate tests (e.g. a t-test) are performed at every voxel in the brain
65
In cognitive psychology, how are "representations" and "operations" distinguished?
Representations are the physical structures of the brain, while operations are the mental processes that occur within those structures.
Representations refer to mental processing and transformations, while operations refer to the information or content held in the mind.
Representations refer to the information or internal code held in the mind, while operations refer to the mental processes and transformations applied to that information.
Representations and operations both refer to the physical activities in the neural circuits of the brain and are, hence, interchangeable terms.
Representations refer to the information or internal code held in the mind, while operations refer to the mental processes and transformations applied to that information
66
The "standard model" of working memory states that more __________ lateral prefrontal regions store ___________ information, while more _________ lateral PFC regions store ___________ information
anterior, object, posterior, spatial
anterior, spatial, posterior, object
dorsal, spatial, ventral, object
dorsal, object, ventral, spatial
dorsal, spatial, ventral, object
67
Serences et al. (2009) showed that early visual regions play a role in visual working memory maintenance by using MVPA to show that
lateral prefrontal cortex is not active during the working memory delay period.
the delay period produces greater BOLD activation in early visual regions compared the inter-trial interval.
tions and colours) can be decoded based on the distributed patterns of activity in visual regions during the delay period.
both the delay period of a working memory task and the inter-trial interval produce very similar BOLD response magnitudes.
the contents of visual working memory (both orientations and colours) can be decoded based on the distributed patterns of activity in visual regions during the delay period
68
The sensory recruitment model proposes that
information in visual working memory is stored in lateral prefrontal cortex
the prefrontal cortex plays no role in visual working memory
posterior brain regions contribution to visual working memory is due to their role in response selection
storing information in visual working memory recruits posterior brain regions that were activated during the sensation and perception of that information
storing information in visual working memory recruits posterior brain regions that were activated during the sensation and perception of that information
69
Oscillations of 0.5 - 4 Hz are known as what?
Delta wave
70
Oscillations of 4 - 8 Hz are known as what?
Theta
71
Oscillations of 13 -32 Hz are known as what?
Beta
72
Oscillations of 8 - 13 Hz are known as what?
Alpha
73
Oscillations of 32- 100 Hz are known as what?
Gamma
74
What functions are Delta waves associated with
Associated States: Deep sleep (non-REM sleep), unconscious states
Functions:
Delta waves dominate during restorative sleep, which is essential for healing and memory consolidation.
They are thought to help in regulating autonomic functions and are often linked to the homeostasis of internal systems.
Disruptions in delta activity can indicate problems with sleep or damage to certain brain regions.
75
What functions are Theta waves associated with
Associated States: Light sleep, drowsiness, meditation, and creative processes
Functions:
Theta waves are observed during states of reduced consciousness such as early stages of sleep and deep relaxation.
They are thought to support memory encoding and retrieval, and are particularly associated with the hippocampus, a region involved in learning and memory.
Enhanced theta activity has been linked to creativity, as well as to emotional processing and decision-making under uncertain conditions.
76
What functions are Alpha waves associated with
Associated States: Relaxed wakefulness, quiet thought, and meditative states
Functions:
Alpha waves typically arise when a person is awake but in a relaxed, non-stimulated state, such as when daydreaming or meditating.
They are often linked to the inhibition of sensory information, allowing the brain to rest and focus on internal thoughts.
Alpha activity is inversely related to cortical activity, meaning that higher alpha activity often signifies less task engagement or sensory input.
77
What functions are Beta waves associated with
Associated States: Active thinking, focused attention, problem-solving, and alertness
Functions:
Beta waves are predominant when we are awake and mentally engaged in tasks requiring attention, such as reading, speaking, or critical thinking.
High levels of beta activity are associated with increased cognitive function, but can also correlate with stress and anxiety when excessive.
These oscillations are also thought to help in the regulation of motor behaviour, playing a role in sensory processing and voluntary movements.
78
What functions are Gamma waves associated with
Associated States: Higher cognitive functions, such as perception, consciousness, and problem-solving
Functions:
Gamma waves are linked to high-level information processing and are believed to support the integration of sensory input from different brain regions, contributing to perception and conscious awareness.
They are important for working memory, attention, and the binding of sensory information into a coherent experience (e.g., combining sound and vision to perceive an object).
Abnormal gamma activity has been implicated in certain neuropsychiatric conditions such as schizophrenia.
79
What phase of neural oscillations are associated with memory encoding and retrieval and the hippocampus
Theta
80
Neural activity in the ___ wave range is INVERSLY related to activity i.e. higher blank waves = less cortical activity
Alpha
81
What wave is mainly active when we are alert and conscious
Beta
82
Which neural wave is associated with higher cognitive functioning, integrating sensory input, and memory and attention?
gamma
83
What are the major themes explored in human neuroscience
Mind-Body Problem: How does the brain relate to the mind?
Organisation of the Nervous System: Can specific cognitive processes be localised to brain regions?
Philosophical Materialism/Monism: Psychological processes are mediated by brain processes, with continuity across species allowing generalisation(neuro Lecture 1 canvas).
84
Define cognitive neuroscience and explain its significance in bridging psychology and biology.
Scope of Human Neuroscience:
Studies the neural underpinnings of human psychology (perception, cognition, motor control, etc.) using a variety of disciplines, such as cognitive, social, developmental, and perceptual neuroscience(neuro Lecture 1 canvas).
Cognitive Neuroscience:
Term coined by George A. Miller and Michael S. Gazzaniga, integrating data from experimental psychology, neuroscience, and pharmacology
Bridging Psychology and Biology:
The challenge is to connect neuroscience with psychology, which involves linking biological processes with psychological theories
85
Explain René Descartes' contribution to human neuroscience and the concept of interactive dualism
Interactive dualism, focusing on the mind and body as separate entities -- Two of everything except for the pineal gland so thought it was the most important believed the vertricles were important in a hydrolic function - came up with the reflex thing
86
How did Thomas Willis' work shift the understanding of brain function, particularly concerning the role of the cortex?
Shifted focus from ventricles to the cortex, establishing that psychological attributes are dependent on the cortex
localisation - more empirically based - mind is what brain does
87
What were the key ideas behind phrenology, and how did they contribute (even indirectly) to the development of neuroscience?
The outdated theory that skull shape corresponds to psychological traits. However, Gall’s ideas on localisation laid groundwork for later neuroscience
88
Describe Santiago Ramón y Cajal’s neuron doctrine and its significance in modern neuroscience.
Santiago Ramón y Cajal: Neurons are the structural and functional units of the nervous system, supporting the idea that brain processes are based on neurons
89
What is EEG, and what key discoveries did Hans Berger make in relation to brain activity and cognitive processes?
Measures electrical brain activity. Developed by Hans Berger, it became a key technique for investigating brain functions and cognitive processes
90
What are the philosophical assumptions of materialism/monism in neuroscience, and how do they shape our understanding of brain and psychological processes?
Overall, materialism/monism in neuroscience shapes our understanding of the mind as inseparable from the brain, guiding research and therapeutic approaches that focus on biological mechanisms to explain psychological processes.
Philosophical materialism or monism in neuroscience is the view that psychological processes, including cognition, perception, and emotions, are entirely the result of brain activity. This perspective assumes that all mental phenomena arise from physical interactions within the nervous system, without the need for non-physical explanations such as a separate "mind" or soul.
91
What are the key functions of neural oscillations in brain activity?
Neural oscillations are rhythmic or repetitive patterns of neural activity in the central nervous system. Their functions include:
Integration of brain areas across different spatial scales.
Providing a background reference signal for timing cell discharge.
Facilitating network formation through coincident activity.
Item integration and segregation for cognitive processes
92
Describe the roles of different neural oscillation frequency bands (e.g., delta, theta, gamma) and their relevance to specific cognitive or motor processes.
Delta (<4 Hz): Typically associated with deep sleep.
Theta (4-7 Hz): Involved in navigation and memory processes, especially in the hippocampus.
Alpha (8-14 Hz): Often linked to relaxation or calm alertness.
Beta (15-30 Hz): Related to motor activities and sustained attention.
Gamma (30-60 Hz): Associated with cognitive processes like attention and perception
93
Which has higher voltage, delta or gamma?
delta, voltage is the opposite of freq. voltage is them all joining together to do the same thing - a Mexican wave rather than everyone clapping but not in sync = lots of activity(freq) but not together powerful
94
Explain how oscillations contribute to the integration of brain activity across different spatial scales.
Different frequencies integrate activity across various distances in the brain, with higher frequencies like gamma operating at shorter distances and lower frequencies like theta supporting long-range integration
95
What is the significance of hippocampal theta oscillations in navigation tasks and memory processes?
The hippocampus plays a crucial role in navigation and memory, with theta oscillations providing a reference signal for the timing of cell discharges. Phase precession allows for spatial and temporal coding by neurons, helping in processes like spatial navigation (place cells) and timing during tasks
96
Define phase precession in the hippocampus and its role in spatial and temporal coding
as the gamma nests in the theta, each gamma records activity for a different placehappening earlier as we get closer
97
How does theta phase influence long-term potentiation (LTP) in neural networks?
Oscillations such as theta waves influence synaptic plasticity. For instance, stimulating at theta peaks promotes LTP (learning-related synaptic strengthening), while stimulation during troughs inhibits LTP
98
What is the concept of theta-gamma nesting, and how does it contribute to item integration in working memory?
Theta and gamma oscillations are nested to encode multiple items in working memory. This mechanism helps in item integration and segregation during memory tasks
99
What is Hebb’s postulate, and how does it relate to the concept of synaptic plasticity?
Hebb’s first postulate: "Cells that fire together, wire together." Repeated activation of cell A firing cell B leads to a strengthening of their connection.
Hebb’s second postulate: Neurons that repeatedly fire together form cell assemblies, which can persist after the initial triggering event, representing the memory
100
Define Long-Term Potentiation (LTP) and explain why it is considered a candidate mechanism for memory storage
LTP is a form of synaptic plasticity that strengthens synaptic connections based on co-activation of neurons. It is considered a strong candidate for the neural basis of memory.
101
Describe the role of NMDA receptors in the induction of LTP.
LTP is induced by repetitive synaptic activity, resulting in an enhanced post-synaptic response. This process involves NMDA receptors and calcium entry into the post-synaptic cell
102
Why is it difficult to study LTP directly in humans, and what methods are used to observe it?
Studying LTP in humans is challenging due to the invasive nature of measuring it directly. However, methods like EEG provide non-invasive ways to observe LTP, particularly through changes in evoked potentials
103
What is the significance of input specificity in LTP, and how does it ensure the precision of memory storage?
LTP is highly specific to the stimuli that induce it, meaning it only enhances the synaptic strength of neurons directly involved in the activity, rather than causing a general increase in cortical excitability
104
How can visual and auditory evoked potentials demonstrate LTP in human models?
Photic tetanus can induce LTP in visual evoked potentials, where specific changes in response amplitude can be detected post-stimulation.
Auditory evoked potentials also show LTP following auditory stimulation (e.g., using tetanus at 13 Hz
105
What are the potential implications of LTP research for understanding and treating memory-related disorders such as Alzheimer's disease?
LTP has been modulated in disorders like depression and schizophrenia, suggesting its potential as a target for treatment. Its role in memory disorders, such as Alzheimer's disease, is also a focus of ongoing research
106
What are the core executive functions associated with the frontal lobes, and how do they influence cognitive behaviour?
The frontal lobes play a crucial role in executive functions, which include skills like inhibition, working memory, and cognitive flexibility. These functions enable us to plan, make decisions, resist temptations, and adapt to new situations
106
Explain the significance of Phineas Gage's case for our understanding of the role of the frontal lobes in emotion and decision-making.
Phineas Gage's frontal lobe injury led to dramatic personality changes, highlighting the frontal lobes' role in regulating emotions, decision-making, and social behaviour
107
Describe the role of the anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex (dlPFC) in the Stroop task.
ACC: Involved in error detection, attentional allocation, and conflict resolution, particularly in tasks like the Stroop task, where it helps manage competing responses.
dlPFC: Plays a role in conflict monitoring and attentional allocation during complex cognitive tasks
108
What is the Stroop task, and how does it demonstrate cognitive control?
This task measures cognitive control by requiring participants to name the colour of words that may be incongruent (e.g., the word "RED" printed in green ink). The ACC and dlPFC work together to resolve the conflict between the word meaning and the ink colour
109
Discuss the different roles of the dorsolateral prefrontal cortex (DLPFC) and ventrolateral prefrontal cortex (VLPFC) in working memory.
The dorsolateral prefrontal cortex (DLPFC) and ventrolateral prefrontal cortex (VLPFC) are key regions involved in working memory. DLPFC is associated with manipulating information, while VLPFC is involved in rehearsal and retrieval
110
What is the function of the ventromedial prefrontal cortex in memory, and how does it contribute to planning and decision-making?
The prefrontal cortex (including ventromedial prefrontal cortex) links current information with past experiences and is essential for planning, organising episodic memories, and source memory (where and when events occurred)
111
explain the role of theta oscillations in spatial and recognition memory.
How are place cells and grid cells involved in theta rhythms, and what cognitive tasks are they important for?
Describe the relationship between theta oscillation amplitude and working memory load.
Generated by interactions between the medial septum and entorhinal cortex, with implications for spatial and recognition memory.
Linked with place and grid cells, which contribute to spatial navigation and memory.
Theta oscillations are prominent during tasks requiring memory scanning and recognition, and their amplitude increases with cognitive load.
112
Alpha Oscillations:
What role do alpha oscillations play in attention and visual processing?
How do alpha oscillations contribute to the segregation or integration of stimuli during perception?
Linked to inhibitory processes and temporal resolution in visual tasks.
They play a role in attention, with higher alpha activity corresponding to suppression of irrelevant stimuli.
2 stimuli arriving on 1 alpha with integrate, if they don't = segreation
113
How does chronic stress impact LTP and LTD in the hippocampus, and what are the implications for mental health?
Chronic stress can shift the balance between LTP and LTD, impairing synaptic plasticity and contributing to mental health disorders like depression and schizophrenia.
The stress hormone cortisol influences plasticity through effects on the hippocampus.
114
How do serotonin and BDNF affect LTP in individuals with depression?
What evidence supports the role of SSRIs in enhancing LTP and cognitive performance?
Involves dysregulation of serotonin (5HT), glutamate, and brain-derived neurotrophic factor (BDNF), which affect LTP.
SSRIs like sertraline enhance LTP and are linked to improvements in memory performance.
115
How is synaptic plasticity disrupted in schizophrenia, and what are the roles of dopamine and glutamate in this process?
Shows disrupted dopamine and glutamate systems, with reductions in NMDA receptor activity contributing to impaired LTP.
Genetic factors (e.g., COMT polymorphisms) and environmental triggers (e.g., cannabis use) play a role.
116
Describe how synaptic plasticity is altered in ASD, particularly in relation to LTP and genetic mutations.
What evidence suggests that ASD is associated with hyper-plasticity?
Involves hyper-plasticity, with augmented LTP observed in animal models of ASD.
Specific genetic mutations, such as those in SHANK2, lead to impaired synaptic plasticity and altered neuronal signalling.
117
How does amyloid-beta disrupt LTP in Alzheimer’s disease?
What are the early biomarkers of cognitive decline in Alzheimer’s, and how do they relate to changes in synaptic plasticity?
Aβ plaques disrupt LTP, contributing to cognitive decline.
Early detection of mild cognitive impairment (MCI) through biomarkers like memory and visuospatial can help identify individuals at risk of progressing to AD.
118
How does an MRI work
a strong magnetic field is applied (B0) which causes all
the protons of hydrogen atoms to “line up” with the
magnetic field.
Step 2: apply a short radio-frequency pulse,
causing protons to tilt away from and then
rotate around B0 (like a spinning top)—this is
called precession
.
When the RF pulse is turned off, the protons
stop precessing, and they emit energy, which
can be detected by the scanner
Different tissue types have different
densities of hydrogen, and so
produce different levels of brightness
in a structural
MRI scan
119
why cant you just run 170,000 t-tests on voxels
bound to get a 5% false positive, which would be a lot - dead salmon
120
what can multivariate pattern analysis help with
drawing associations between patterns of brain activity and mental states
can create a correlation matrix - ie voxels commonly lit up for faces
mind reading - trump and kamala dots activating
121
Magnetic signal of the blood differes according to how oxygenated it is, which is repelled or attracted by the magnetic field - oxygenated of deoxygenated blood?
oxygenated REPELS
deoxygenated ATTRACTS
122
why would we need subtraction for a cognitive task in the MRI
if i have a task about memory, I can do a new task that doesn't require memory, and then use that to subtract the things that are the same - removing variables
123
What is forward inference
design exp that manipulate cognition the see how its correlated with differences in the brain
124
What is a representation?
internal code
that “stands in” for the shape
that’s out there in the world.
125
What are the 3 parts of baddeleys cognitive model
what are its criticisms
visuospatial sketchpad - central executive - phonological loop
How many buffers are there?
* Dissociations have been found for multiple visual features/properties..
* What about other modalities? (e.g. olfaction?)
126
why do we think baddeleys two storage systems are separate? (visuospatiol vs phonological loop)
Double dissociation between the two storage systems:
* secondary verbal tasks disrupt information in the PL (but not the VSS)
* secondary visuospatial tasks disrupt information in the VSS (but not the PL)
127
Dorsolateral = ______information
Ventrolateral = _______information
spatial
object
128
If not storage, what is the PFC’s role in working memory?
Several possibilities exist:
1. PFC may, via reciprocal connections, maintain posterior regions in an
active state.
2. PFC may prevent disruption of WM representations by suppressing
sensory processing of environmental stimuli. In other words, it could be
involved in orienting attention to internal representations(as opposed
to external stimuli).
3. It could correspond to processes that have to do with response
selection
129
What is "Cortical reinstatement"
Cortical reinstatement,
coordinated by the
hippocampus, ensures
patterns of activity that
were present at encoding
are reactivated during
retrieval
130
What is the role of the entorhinal cortex
The entorhinal cortex is the “bridge” between
the hippocampus and the cortex—receives
inputs from a range of sensory and association
cortical regions, either directly or via perirhinal
and parahippocampal cortice
131
How do grid cells map for spatial location?
Each grid cell fires not just at one spot (place cells), but at several spots arranged in a hexagonal grid across the environment.
Grid cells don’t work alone. A population of grid cells, each with its own specific hexagonal grid pattern, fires together as the animal moves. These patterns have different scales and phases (starting points), so the combined activity of many grid cells can uniquely code for almost any location within a space.
increase in activation depends on whether or not you are on 'the 60 degree line'
132
Beyond navigation and memory, what else is the hippocampus implicated in?
imagining the future
working memory
fine grained perceptual judgements
133
What makes pyramidal neurons the primary contributors to EEG signals compared to other neuron types?
EEG measures brain electrical activity, capturing postsynaptic potentials primarily from cortical pyramidal cells due to their "open-field" orientation.
134
Explain the process of time-locked averaging in ERP analysis.
Why is noise reduction critical in ERP studies, and how does averaging improve the signal-to-noise ratio?
ERPs are extracted from EEG by averaging time-locked responses to specific events, such as visual stimuli. This process reduces noise, making task-related signals more visible.
135
Describe the role of the N170 component in face processing. How does it differ from the N250?
N170: A negative peak around 170 ms post-stimulus, primarily associated with face processing.
Linked to face identity recognition, showing increased amplitude for familiar faces or faces closely resembling a "target" image.
136
How does the P200 component vary with face typicality, and what does this suggest about the cognitive processing of faces?
P200: Sensitive to face typicality, with higher amplitude for "average" faces -- perhaps we recognise them by how far they deviate from the norm
137
What distinguishes P3a from P3b in the oddball paradigm?
P3a is evoked by novel or distracting stimuli, while P3b responds to target stimuli in oddball paradigms.
138
Describe the role of MMN in predictive coding and the significance of mismatch signals.
MMN is generated in response to unexpected sensory inputs, such as deviant auditory tones, and can occur without conscious awareness.
139
what does the P3b represent?
P300 (P3b): Reflects "context updating" or cognitive-level prediction updating, particularly in attention and memory tasks.
enhanced P3b components for attended stimuli.
140
How does predictive coding theory explain the brain's processing of sensory information?
The brain operates as an inference organ, predicting external events through top-down processing (e.g., predictions originating in the frontal lobes).
Predictive coding proposes that perception is hypothesis-driven, with mismatch signals (e.g., MMN) reflecting prediction errors when unexpected stimuli occur.
141
What is the Subsequent Memory Effect (SME), and how is it reflected in ERP components?
Subsequent Memory Effect (SME): The P3b amplitude is greater for stimuli later remembered, suggesting attention aids in forming stronger memory traces.
142
Describe the Contralateral-Control Method and its use in studying visual short-term memory.
The Contralateral-Control Method leverages crossed neural pathways to analyze ERPs related to spatial processing, revealing lateralized responses in tasks like visual search and memory retention.
ie did we get activity on the LHS when using the RH
143
Describe the role of P3b in the Global Neuronal Workspace Theory. How does this theory explain conscious awareness?
Proposes that conscious awareness emerges when information is globally broadcasted across a network, highlighted by the P3b component. This “workspace” allows selective amplification and sharing of relevant information among brain regions.
P3b is seen as a marker for conscious processing, especially in tasks like the "attentional blink" where subjects report awareness of stimuli after a delay.
144
How does GNWT differ from traditional modular theories of the mind?
In summary, GNWT presents consciousness as an emergent property of distributed processes and widespread integration, whereas traditional modular theories posit that the mind consists of independent, specialized modules with limited interconnectivity.
145
What is the role of the P3b in predictive coding, and how does it differ from the MMN and N400?
The P3b reflects “context updating,” while the N400 reflects “semantic updating,” as in cases of encountering unexpected language or meaning. MMN does not require any awareness
146
How does the predictive coding framework explain perception?
Suggests that the brain acts as a prediction-making organ, where incoming sensory inputs are continuously matched against top-down predictions. Errors between predictions and actual sensory inputs lead to "prediction error" signals like the MMN, P3a, and N400
147
What distinguishes structural MRI from functional MRI?
Structural MRI: Used for anatomical imaging by differentiating tissues based on hydrogen density.
Functional MRI: Captures brain activity over time by measuring changes in blood oxygenation.
148
Describe how the BOLD signal reflects neural activity indirectly. Why is oxygenation important?
fMRI relies on the BOLD effect, which measures changes in blood oxygen levels that correspond to neural activity. Increased neural activity in a brain region leads to higher oxygenated blood flow, which fMRI detects
149
Explain how task-related fMRI uses subtraction to identify cognitive processes.
Often used to identify brain areas involved in specific cognitive tasks by comparing brain activity across different conditions using the General Linear Model (GLM). Subtraction techniques help isolate task-relevant brain activity
150
Describe how MVPA can be used to decode mental states?
A method to analyze patterns of brain activity across distributed networks, often used to identify specific mental states. MVPA can even “decode” these states by using machine learning to recognize patterns linked to different stimuli.
151
What are some advantages of using MVPA in studying distributed brain activity?
MVPA allows researchers to investigate the distributed patterns of brain activity rather than individual voxels, enabling the identification of mental states through brain activity patterns.
This method has drawn parallels between AI (e.g., word embeddings) and human brain representations, suggesting a systematic relationship between external stimuli and brain activity.
152
Why is it problematic to interpret fMRI activation as evidence that a region is essential for a cognitive function?
fMRI is correlational, meaning that observed activation in a region does not confirm that it is essential or sufficient for a specific function.
any given region may be involved in many processes , its not a 1-1 mapping
153
Describe the difference between forward and reverse inference in fMRI studies and explain why reverse inference is unreliable.
Issues such as reverse inference (inferring cognitive processes from brain activation) can lead to incorrect conclusions because brain regions often support multiple functions.
fwd means we take a given location and try to create activation
154
Explain the double dissociation (the separation of parts) between verbal and visual-spatial storage systems in Baddeley’s model.
Proposes two separate systems for verbal (phonological loop) and visual-spatial (visuo-spatial sketchpad) information, managed by a central executive.
Studies suggest double dissociation (independent disruption) of these systems, supporting Baddeley’s model. - one loop doesn't affect the other suggesting they are separate
155
What are some criticisms of Baddeley’s model regarding its application to other sensory modalities?
doesn't account for all the other sensory modalities
156
How does the sensory recruitment model propose that WM content is maintained after sensory input ends?
Suggests that WM is not stored exclusively in PFC but relies on sensory and perceptual regions to maintain information after sensory input ends.
MVPA studies show that distributed patterns in early visual regions hold WM content, indicating WM representations may persist in sensory areas rather than transferring to PFC.
157
According to the sensory recruitment model, what role does the PFC play in WM if it does not serve as the primary storage site?
Instead of storage, the PFC may play a role in maintaining active states in posterior sensory regions and directing attention to internal representations by suppressing sensory input, thereby protecting WM from interference.
158
Describe the role of the entorhinal cortex in connecting the hippocampus with the cortex.
The entorhinal cortex serves as a bridge, integrating input from the cortex and relaying it to the hippocampus.
159
What are the primary functions of the hippocampus, perirhinal cortex, and parahippocampal cortex within the MTL?
Episodic memory, spatial navigation, future imagination, perception
160
Explain how patient H.M. contributed to understanding the role of the hippocampus in memory.
The hippocampus is critical for episodic memory, as shown in amnesia cases like patient H.M., and is active during both encoding and retrieval stages, coordinating cortical activity patterns for memory reactivation.
When HM HC was removed he lost the ability to form memories
161
What is cortical reinstatement, and how does the hippocampus facilitate this process during memory retrieval?
HC is active during both encoding and retrieval stages, coordinating cortical activity patterns for memory reactivation. by reactivation the same pattern
162
What is the function of place cells and grid cells, and how do they contribute to spatial mapping?
How does direction and speed modulate grid-cell-like responses in the entorhinal cortex, according to fMRI studies?
The hippocampus is essential for spatial mapping through place cells that activate in specific locations and grid cells in the entorhinal cortex that provide a hexagonal spatial representation.
Research, including VR-based fMRI studies, shows that direction and speed influence entorhinal activation, with pronounced effects during faster motion aligned with grid-cell patterns.
163
How does hippocampal activation during imagining future events
Addis and colleagues (2007), demonstrate that during tasks requiring future imagination, the hippocampus is more active compared to tasks that involve recalling past events. This differential activation highlights the hippocampus’s role in “constructing” new, rather than merely “retrieving” old, scenarios.
The hippocampus helps piece together elements from past experiences (like people, places, and events) to create new imagined scenarios. This is known as scene construction, where the brain synthesizes spatial and contextual details to form coherent mental images of potential future events.
By enabling the flexible recombination of elements from past memories, the hippocampus allows us to create novel scenarios. Patients with hippocampal damage often struggle with future-oriented thinking, which can impair their ability to make decisions, engage in long-term planning, and visualize personal goals.
164
Clinical classification of Huntingtons disease, of when you become symptomatic is based entirely on what ......
presence of abnormal motor symptoms BUT peoplewho work in the field will tell you this is not the case, and may have one of the other domains showing first
165
What is Marrs 3 Levels of Analysis (not identification)
Computational Level: Defines the "what" - the goal of the system.
Algorithmic Level: Explains the "how" - the processes and representations used to achieve the goal.
Implementational Level: Describes the "where" - the physical substrate that performs the process.
166
What are some hippocampal functions 3x
Pattern Separation: Distinguishes between similar events in memory, especially in the dentate gyrus (DG), which creates distinct neural patterns for similar inputs.
Pattern Completion: A partial cue can trigger the full memory of an event, aided by hippocampal interactions with cortical areas to reconstruct missing information.
Relational Processing: Integrates various sensory inputs across time and space, vital for complex memory and spatial navigation.
167
What is event segmentation
The brain organizes continuous sensory input into discrete events, a process relying on predictive coding. This involves updating mental "event models" when there is a mismatch between expected and actual sensory input.
The brain uses predictive coding to anticipate incoming sensory information. When unexpected changes occur, the brain detects prediction errors, triggering a reset and forming a new event model.
Event boundaries (e.g., a scene change in a movie) represent shifts where the brain updates its model, strengthening memory encoding.
168
Explain the role of the hippocampus in pattern separation. How is this process essential for distinguishing between similar experiences?
Distinguishes between similar events in memory, especially in the dentate gyrus (DG), which creates distinct neural patterns for similar inputs.
patterns are encoded in a way that allows for them to be distinguishable
if memories are too similar you only can recall the gist - pattern separation makes things as dissimilar as possible
Study - videos around Paris - first few rounds had a similar pattern but as they learned the routes they HC gave different pattern representations
Studies show the DG responds uniquely to similar but non-identical stimuli, aiding in memory specificity.
169
What is pattern completion, and how does it enable the brain to recall an entire event from a partial cue? and the significance of TMS findings in supporting this process.
Enables retrieval of a full memory from partial cues. If presented with a cue, the hippocampus can reassemble associated details, completing the memory pattern.
Research using TMS to manipulate connectivity shows that hippocampal activation supports reactivation of the original memory patterns during recall.
170
How does the brain decide when one event ends, and another begins? What are “event boundaries” and their significance for memory?
The brain organizes continuous sensory input into discrete events, a process relying on predictive coding. This involves updating mental "event models" when there is a mismatch between expected and actual sensory input.
very strong consensus on where event boundaries are among participants
often studies in a natural setting making it hard to control variables, bt good for validity
increase in HC activation at event boundary suggesting increased encoding of event boundary into episodic memory is linked to hippocampal activation
171
What is relational processing? why is it essential for memory and navigation?
Integrates information across time and space, supporting episodic memory and spatial navigation.
Studies have shown that hippocampal activation increases for tasks requiring associations (e.g., remembering an object and its context).
Sudy - hippocampal amnesics showed no difference for recall or location but had trouble putting the two together - which is a deficit specific to relational processing
172
How does impaired event segmentation contribute to memory deficits in clinical populations like Alzheimer’s?
event seg is related to memory performance, in AZ or these with memory deficits, the conflict that encourages the reset of the model may be affected - maybe they have trouble 'updating' which may be related to the fact they find it hard to change tasks
173
What is cortical reinstatement, and how does the hippocampus facilitate this during memory retrieval?
The hippocampus facilitates encoding and retrieval by coordinating cortical reinstatement, or the recreation of memory patterns during recall.
174
How does the brain age normally?
cog changes can occur in most domains from 30's sometimes 20's
over the life time there is a decline in speed, memory and reasoning BUT an incline or stable vocab and semantic knowledge as we acquire more knowledge
as we age lateral ventricles get bigger while hippo and thalamus decrease, structural integrity of white matter breaks down
175
why dont we always notice a decline in cog abilities/neurodegeneration
You may not notice changes in daily life because you don't usually get challenged to the level you would in intensive cog testing.
people could be using compensation
176
the majority of studies in cognitive decline are cross-sectional; why is longitudinal better ?
cross-sectional may be affected by cohort differences, and may OVERESTIMATE age related differences. They give us a downward trajectory .
Longitudinal - gives us a more stable pattern with a eventual rate of decline - not sharp- and what has been changing, but could be affected by attrition or practice effects
177
What are the 3 theories of cognitive change?
The information degredation hypothesis - that perceptual signals like vision and hearing are weakened with age and results in impaired processing and requires a high cog load to process information
The common cause hypo- we all have a decline in these abilities but due to a common biological factor
Sensory deprivation hypo- lack a sensory info over time leads to gradual atrophy and loss of cog function
178
what does cardiovascular health have to do with aging and AZ?
cardiovascular problems increase with age
- theres an increased risk of damage to the blood vessels which would result in a reduction in the supply of oxygen, glucose and blood
- affects BBB messing up waste removal
179
Ageing in later years is typically associated with changes in brain structure and cog scores BUT doesn't necessarily mean loss of cog functioning; some are old and quite coherent - how do they remain high functioning ?
- Neural changes may be offset by neural resources (reserves, maintenance, compensation) that support declining abilities and cog performance
180
what are 4 things that can contribute to the changing of brain structure and function
neural resource enrichment
'neural resource depletion,
biological aging
life experiences
181
what is Compensation?
the act of using additional activation to minimise decline
More brain activity in the circuits that usually do the task or recruitment of additional regions
only deemed Compensatory if the persons level of performance is ELEVATED - someone could have more activity and no do well which is not the same
older adults with often employ both sides of brain while younger will only need one.
CRITICAL to consider how the task is being performed - different strategies.
limits on how much scaffolding can be done
182
what is dementia?
an umbrella term for symptoms of brain disease that impairs cognition, memory, thinking and daily activities of living
Dementia is receached when a person is struggling to function normally
183
what is 5 of the the clinical criteria for AZ ?
1. objective difficulty in two or more domains - memory/language, visuospatial/abstract thinking
2. gradual onset and progressive worsening of of memory and other cog functions
3. no disturbance of consciousness (delusions)
4. impaired activities of daily living
5. exclusion of other disorders
184
In AZ which of the 3 domains would difficulty retreiving words and errors in naming tasks come under?
memory impairments (episodic, semantic)
185
in AZ what would be examples of attentional and executive functioning impairments?
reduced working memory, difficulty task shifting, difficulty planning and organising trouble solving multistep problems
186
problems with free drawing or copying and loss of spatial navigation fall under which domain in AZ?
visuospatial constructional impairments
187
does the detection of amyloid mean you will get AZ?
no - only combo of AB and cognitive issues
188
What are the contributing factors of AZ? both non-modifiable and modifiable
Aging is biggest factor
genetics - APOE strongest risk indicator but not confirming 50 % chance of inheriting
modifiable-
low education
smoking / heavy alcohol use
physical inactivity/obesity/diabetes
depression
hypertension
TBI
189
AB lowering treatments can help to breakdown AB but what are the negitatives?
cost v risk is not very good
slows rate of decline but effects are modest and many ppl arent eligible
190
What is cognitive reserve? and what contributes to it?
Cognitive reserve allows maintenance of "adequate functioning" LONGER in the face of pathology (keeps people functioning for longer)
individual differences in cog ability
compensation (recruitment/neurogenesis)
individual differences in neural activity and networks
cognitive reserve may mediate between AD pathology and its clinical expression - not slowing it down but our brains can work around it
191
What is Parkinsons
neurogenetive disorder, specific type of motor disorder, disturbances of affective function, cognition and autonomic function
192
What are the Parkinsons' symptoms 4x
1. resting tremor - pill rolling
2. muscle rigidity
3. bradykinesia - slowness of movement difficulty initiating and sustaining voluntary movement
4 postural instability
Motor signs
stooped posture, shuffling gait, absence of arm movements
reduced voice volume and inflection
small handwriting
non-motor
loss of smell
sleep disorders
dysphagia
loss of libido
sweating
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IN pARKINSONS what are and both motor and non-motor signs? and mood symptoms
Motor signs
stooped posture, shuffling gait, absence of arm movements
reduced voice volume and inflection
small handwriting
non-motor
loss of smell
sleep disorders
dysphagia
loss of libido
sweating
affective//mood
depression - OFTEN PRECES ONSET OF MOTOR SYMPTOMS
anxiety
psychotic associated with older patients and high levels of dopa meds - hallucinations
impulse control disorders (binge shopping/eating), gambling
194
what is the neural basis of Parkinson?
1. death of dopaminergic cells of
substantia nigra
2. presence of Lewy bodies in
surviving SN cells (initially)–
Lewy bodies: inclusions
composed of neurofilaments
and
“alpha-synuclein aggregates”
and ubiquitin–the misfolded protein!
195
How does of Dopamine reduction cause symptoms
DA takes the breaks off the thalamus, leading to problems with inhibition and excitation in the motor centers
substaintia niagra compactus disrupts the dopamine going into the rest of the circuit.
196
in Parkinsons theyres no symptoms until ....
60-80% of dopamine neurons have died
197
What is the treatment for Parkinsons and how does it work?
Levo-dopa
cant just put DA back in because it cant pass the BBB. LEVO-DOPA which is a pre-cursor to DA can pass BBB and helps remaining neurons to produce DA
--- But - relies on the remaining neurons which will soon run out so it loses its efficacy eventually, side effects can be problematic - high levels of DA can cause psychosis, excessive movement
198
What is phase precession
Phase precession is a neurophysiological process in which the time of firing of action potentials by individual neurons occurs progressively earlier in relation to the phase of the local field potential oscillation with each successive cycle.
Wikipedia
199
What is phase precession
Phase precession is a neurophysiological process in which the time of firing of action potentials by individual neurons occurs progressively earlier in relation to the phase of the local field potential oscillation with each successive cycle.
Wikipedia
