Cog and Bio Flashcards
what are the three directions in which we can slice the brain
horizontal (top-bottom), ventral (left-right) and sagittal (front-back)
functions of the frontal lobe
○ Movement
○ Personality
○ Impulse control
○ Judgement and planning
○ Involved in executive behaviour
functions of the occipital lobe
visual processing
temporal lobe
- High level visual processing in the inferior
- Object and face recognition in the inferior
Auditory cortex in the superior
- Object and face recognition in the inferior
parietal lobe
- Somatosensory perception
- Intersensory integration
- Spatial vision
- Spatial attention
If lesioned there can be visual neglect, only attending to what is processed
cerebellum
- Balance
- Motor planning
- Motor learning
Eye movement control
brain stem
- Breathing
- Heartbeat
- Artery dilation
Salivation
locations in the neuron and their functions
- Input zone - receives information from other
cells through dendrites- Integration zone - cell body transforms and
combines inputs - Conduction zone - a single axon leads away
from the cell body and transmits electrical
impulse - Output zone - axon terminals at the end
communicate activity to other cells
- Integration zone - cell body transforms and
describe the process of synaptic transmission
- The inside of the cell is more negatively charged than the outside
- The ion channels can enter the cells and change the charge of it
- Once it reaches the threshold for an action potential, there is an influx of positively charged ions (this is the action potential). And the neuron fires
- The pre synaptic neuron will send neurotransmitters across the cleft
- These bind to the post synaptic neuron
- We can have excitatory or inhibitory neurotransmitters
- These either make it closer to fire (more positive) or less likely to fire (more negative)
These will summate and may reach the threshold to fire.
how does an EEG work
- Records synchronised post synaptic activity or similarly oriented pyramidal cells
We record post rather than pre as this change lasts longer so has more time to summate and be detected
pros and cons of EEG
- Uses electrodes on the scalp
- High temporal resolution
- Lose spatial resolution
Relatively cheap
how does MEG work
- Measures changes in the magnetic field generated by the same neural populations with sensors
More sensitive to tangential dipoles
pros and cons of MEG
- High temporal resolution
- High spatial resolution
- Expensive
Must be done in a magnetically shielded room
time domain vs frequency domain
Time domain
- Tells us about changes in activity over time
- Often use ERP (event related potentials) by
Averaging many trials over a specific event
Frequency domain
- Tells us about the frequency content of the signal,
How much of a given frequency is present in the
Signal
or we can have time-frequency which is both teehee
when would you use an intercranial EEG
if the person already has or needs electrodes on the surface of the brain for medical reasons
how does MRI work
- When the body is in a strong magnetic field, a majority of H protons will line up parallel with the field creating a longitudinal net magnetisation vector
- Then energy is applied to the system
- Protons will get knocked into a different orientation
- Protons will start spin around their axis at the frequency of the pulse and thus in sync creating a transverse vector
- After the pulse protons return to their original orientation
- During this return, an electrical signal is induced
○ T1 recovery is for longitudinal magnetisation,T2 is for transverse
○ This return will take different amounts of time for different tissues
○ This is based on the density of H atoms and their molecular formula
We can use these pulse sequences to produce an echo and then generate an image
how do we measure brain activity with fMRI
- Blood flow increases to active brain regions, lots of oxygenated blood increases the oxygenated haemoglobin concentration
- oxygenated and deoxygenated blood have different magnetic properties
○ Oxy doesn’t distort the field, deoxy does, it will be brighter (this is seen on a T2 weighted image)
This is the blood oxygen level dependent (or BOLD) signal
- oxygenated and deoxygenated blood have different magnetic properties
analogous traits
traits shared as a result of convergent evolution
homologous traits
traits shared as a result of being related
what is ethology
the study of animals in their natural habitat
premise of behavioural ecology
- Denied consciousness and cognition in animals
- Say animal behaviour as just stimulus and response due to reward and punishment
Now we know it is stimulus, representations and then response
- Say animal behaviour as just stimulus and response due to reward and punishment
premise of the philosophy of mind
- Animals process information, but is this accompanied by subjective experience?
Computers have cognition but no conscience
examples of comparative psychologists
Darwin, Pavlov, Morgan, Skinner, Lorenz, Harlow, Terrace
anthropocentrism
regarding the world in terms of human values and experiences, e.g. Just because an animal uses a tool doesn’t mean they’re actually intelligent, and just because we can’t distinguish 1000’s of smells like a dog doesn’t mean we’re not intelligent
anthropomorphism
attributing human traits, emotions and intentions to animals
what are our closest ancestors
Bonobos and chimps
what is the ecological hypothesis for selective pressure to have a larger brain
cognitive maps, how to reach multiple food sources whilst using the least amount of energy, this takes complex cognition (there is little evidence of this
social hypotheses
social complexities e.g. engaging in social trade, mate guarding and alliance formation in order to mate.
these are all cognitively and socially complex considering the friendship, and enemy. this knowledge is non-egocentric which we know is complex.
evidence of social complexities being a cause of larger brains
as a primate has a bigger social group, they have a larger neocortex ratio
our understanding of primate theory of mind
chimps can understand intention, they also pass the sally-Anne task showing they do have a theory of mind
what is contagion (social learning)
we do what our peers are doing e.g. laughing or yawning
what is stimulus enhancement (social learning)
simpler than imitation, attending to something because someone else is there, learning through trial and error what the other was doing and why
what is imitation (social learning)
copying a novel sequence of actions
what is goal emulation (social learning)
the subject infers the model goals and customises it’s own actions and replacing it with it’s own
Roles of olfaction: hazard detection
a lack of sense of smell leads to increased risk of gas incidents, gas scares, work incident and food related incidents
what is the Proust effect?
when a sensory stimulus triggers a memory
Roles of olfaction: social functions
young infants seek out the smell of their parents, encouraging positive emotional experiences. New borns have a preference for the scent of their mother.
adults can sleep better when exposed to their partners smell.
Roles of olfaction: memory functions
the Proust effect
Roles of olfaction: wellbeing functions
odours can have an effect on mood, e.g. lavender making you more relaxed and lemon having a positive effect on cognition.
Roles of olfaction: eating drinking
sense of smell is needed for flavour perception.
it may also help regulate eating behaviour (smelling savoury food makes you want to eat savoury foods more and sweet foods less)
orthonasal vs retro nasal
ortho - just smell
retro - smell which produces flavour
where is the peripheral olfactory system?
within the nose (compared to central being in the brain)
what does the peripheral olfactory system do?
air (and thus odour) molecules are transported through the nasal passages and to olfactory receptors in the epithelium. The axons of these receptors synapse with neurons from the central olfactory nervous system.
how is odour detected?
odour is made of of many different particles, these attach onto different receptor neurons which allows for the identification of odour.
route of olfactory signals
nasal passage, olfactory receptors in the epithelium, olfactory bulb, primary olfactory cortices then secondary olfactory regions.
what does the trigeminal system do?
when activated, it leads to somatosensory sensations such as pain or temperature. e.g. some smells resulting in stinging.
where are the trigeminal nerves?
in the nasal cavity
what is the piriform cortex involved in?
processing both initial chemical structure of the odour and it’s perceptual dimensions such as pleasantness and quality
how may the piriform cortex play a role in the semantic processing of odour?
reading odour labels and viewing images or odour related objects can can activate the piriform cortex. imagining pleasant and unpleasant odours has been found the cause activation patterns in the piriform cortex that mirror that of olfactory perception.
where is the entorhinal cortex?
it is part of the primary olfactory network
what does the entorhinal cortex do?
acts as a gateway to the hippocampus
what disease can impact the entorhinal cortex
Alzheimer’s impacts the entorhinal cortex first. it is suggested that this contributed to the reduction of memory and olfactory functions
what does the amygdala do (olfactory)
it’s role in the olfactory network may explain the highly strong and unique nature of olfactory evoked memories.
it is also suggested that the amygdala plays a role in odour pleasantness and intensity processes, olfactory associated motor responses and cross-modal processing
functions of the hippocampus in olfactory processing
given the role of the hippocampus in declarative memory processing, this may also explain the emotional nature of scents
it maintains both odour associated episodic memories and sematic knowledge of olfactory concepts.
thalamus’ role in olfactory processing
sending olfactory signals to higher order regions
olfactory is the only sensory modality that is not processed in the thalamus first.
insulas role in olfactory processing
play a key role in evaluating valence of olfactory stimuli.
orbitofrontal cortex’s role in olfactory processing
plays a role in conscious and unconscious olfactory processing, valence processing and multisensory integration.
what are cross modal associations shaped by?
repeated exposure to objects, physiological similarities, semantic similarities, emotion
electrophysical methods to measure olfactory functions
aim to measure the electrical activity in the brain when smelling odours.
look at olfactory event related potentials.
imaging methods to measure olfactory functions
both structural and functional imaging can be used
MRI techniques are used to measure volume of olfactory structures
psychophysical methods to measure olfactory functions
aim to test what the individual can consciously perceive.
often seen as subjective.
there are screening tests to classify normal from abnormal functioning.
what can influence psychophysical methods to measure olfactory functions
tests can be influenced by culture, learning effects and semantic memory.
what does olfactory threshold rely on?
tests can measure olfactory threshold which relies on peripheral olfactory processing, discrimination and identification
examples of psychophysical methods to measure olfactory functions
university of Pennsylvania smell identification test (Doty et. al., 1984) - can be self administered
the sniffin’ sticks olfactory test battery (Hummel et. al., 1997) - can not be self administered
self-rated questionnaires methods to measure olfactory functions
subjective, cheap and easy to do, but discrepancies can be found e.g. English Olfactory Disorders Questionnaire
how does olfactory dysfunction impact patients?
increased eating due to seeking out tastes, and reduced eating (and therefore weight loss) due to a lack of enjoyment from food.
anxiety about hazards and personal hygiene.
frustration due to lack of treatment options.
difficulty in intimate relationships.
trouble bonding with children.
types of olfactory dysfunction
can be quant;
hypersomia - high sensitivity
normosomia - normal
hyposomia - decreased
anosomia - no function at all
or qual;
parosmia - distorted perception of odour in the presence of a source
phantosmia - distorted perception of odour in the absence of a source
causes of olfactory dysfunction
age
infections (both viral and bacterial)
head injury
sinonasal disorders
neurodegenerative diseases
ideopathic (no established cause)
what can olfactory loss lead to?
poorer ability to image smells, worse memory
what is the route of the visual system?
external world - eye - retina - primary visual cortex - rest of the brain
what is light?
waves of electromagnetic energy
iris and pupil ( what are they and what do they do)
irises - bands of contractile tissue that regulate the amount of light reaching the retina
pupil - hole in the centre of the iris that allows light to enter the retina
sensitivity vs. acuity
bright = small pupil and better acuity
dim = bigger pupil to let more light in, worse acuity and more sensitivity
what does the lens do (in the eye)?
focuses light on the retina
what do cillary muscles do?
alter the shape of the lens as needed - this is called accommodation and it brings images into focus
what is binocular disparity?
the difference in the position of the same image on two retinas, t is greater for objects closer to the eye. the visual system using this to make a 3D precept from the 2D retinal images.
what does the retina do?
it converts light to neural systems through a series of receptors, conducting them to the CNS and participates in the processing of these signals.
photopic vision
good light, high acuity, in colour and is cone mediated
scotopic vision
dim light, low acuity, high sensitivity, lacks colour and is rod mediated
what are bottom up processes in perception
processes driven by sensory information from the external world
what is the law of pragmaz (perceptual organisation)
we typically perceive the simplest possible organisation of the visual field
what is subjective contour?
contour that is physically absent in the stimulus but is filled in by the visual field
limitations of the gestalt approach to perception
- It provides descriptions but not examples
- The findings are most based in 2D patterns
- It does not account for the role of top-down processes
It overlooks the role of motion
what is the direct perception approach to visual perception
- Perception is for action, not recognitions
- Visual environment provides enough information for perception
Research should reflect the real world
- Visual environment provides enough information for perception
what is optic array
the pattern of light reaching the eyes (changing due to motion is known as optical flow)
strengths and limitations of the direct perception approach
- It provides a different perspective on perception
- However is radical and oversimplified
It does not explain how the action is executed
- However is radical and oversimplified
what are top down processes
driven by knowledge, expectations and goals
recognition by components theory of visual perception
objects are represented as the basic components (geons) and their spatial relations
what does viewpoint invariant mean in visual perception and which theory has this assumption?
recognition should be equally rapid and accurate across different viewing angles
recognition by components theory
multi-view theory of object recognition
Object representations are collections of views that depict the appearance of objects from specific viewpoints.
This means recognition is viewpoint dependent (i.e. Is better in some views than others)
compare multi-view theory to recognition by components theory
- Multi-view applied to recognition of within-category exemplars, whereas the RBC theory has difficulty doing so
- Multi-view emphasises the importance of previous experience, whereas the RBC theory highlights more on the bottom up process
Multi-view is computationally expensive, RBC is less so
- Multi-view emphasises the importance of previous experience, whereas the RBC theory highlights more on the bottom up process
what makes face recognition special?
it is subordinate level recognition and is sensitive to the spatial relation of face parts (holistic)
this leads to the face inversion effect and composite face effect.
evidence to suggest that face recognition has a dedicated neural network
the fact that some people have prosopagnosia (failure of face recognition without deficit in general object recognition)
is AI as good as object recognition as people are
for object recognition yes, but not for facial recognition
how does ASD affect perception of biological motion
it is impaired, which may be related to the impaired social skills characteristic of ASD
what brain areas are involved in perception of biological motion?
posterior STS, inferior frontal cortex, and premotor cortex show stronger neural activity to biological motion than to non-biological.
face-related brain areas but not body related brain areas are also related
three types of attention
focused (selective)
sustained
divided (multitasking or task-switching)
why do we need attention?
the cognitive system does not have the capacity to process everything
early selection account of attention
attended stimuli are deeply processed
only the basic physical features of unattended stimuli are processed
there are filters to determine what to attend to
evidence for early selection account of attention
dichotic listening and shadowing
what is the cocktail party effect and why is it an issue fir the early selection account of attention
the idea that even mid conversation at a bust party, you hear and will attend to someone saying your name.
it suggests that personally relevant information can break the filter
what is Triesman’s attenuating filter model
suggests that an all of nothing filter is inflexible
suggests highly relevant unattended information can break through the filter
evidence for late selection account of attention
the Stroop effect.
negative priming (suggests that ignored distractors are processed)
late selection account of attention
all information is processed
inhibition prevents action being guided by distracting information
perceptual load theory
suggests that some things take lots of capacity to pay attention to (so we miss other things) and other tasks use less capacity so we can pay attention to multiple small things at once
flanker interference (attention)
we are quicker to process congruent information even when we are told to ignore one piece of information suggesting interference
perceptual load of attention and ASD
people with ASD traits usually have higher perceptual capacity
feature integration theory
suggests that we have topographical maps for simple features
and that it is attentions job to bind the features to a single representation of an object
what three stages do memories go through
encoding, storage and retrieval
three types of polysomnography
EEG - brain activity
EOG - eye movements
EMG - muscle activity
what are the 4 sleep stages
REM
NREM1
NREM2
NREM3 (or slow-wave)
how long is one sleep cycle?
90 mins
describe sleep stage NREM1
low amplitude mixed frequency, slower than wakefulness brain activity
slow rolling eye movements
lower muscle activity than wake
describe sleep stage NREM2
K complexes and sleep spindles in brain activity
unremarkable eye movement
lower muscle activity that wake
describe sleep stage NREM3
slow wave activity in brain
unremarkable eye movement
lower muscle activity than wakefulness
describe wakefulness in terms of EEG/EOG and EMG
low amplitude mixed frequency brain activity. alpha rhythm in occipital channel
eye blinks
higher muscle activity than sleep
describe REM sleep stage
low amplitude mixed frequency brain activity. no oscillation , sleep spindles or k complexes
rapid eye movements
lowest muscle activity
the active systems model of memory consolidation
during sleep we use slow waves and sleep spindles to consolidate memories
sleep also facilitates memory distribution as longer SWS duration was associated with superior recognition
when we sleep memories leave the hippocampus and are consolidated in other areas of the brain such as the neocortex, leaving the hippocampus ready with it’s full encoding capacity again
how do we transform everyday experiences into enduring memories?
new memories are initially weak and susceptible to interference
over time new memories are strengthened and integrates into existing knowledge structures
this is facilitated by brain activity such as slow wave activity while sleeping
how to we encode new memories without overwriting existing ones?
the hippocampus is critically involved in memory encoding
sleep-associated memory consolidation redistributes new memories from the hippocampus to the neocortex
meaning of skill vs expertise
skill - the capacity to do something well regarding technique
expertise - requiring innate abilities? or can we be an expert just from practice?
how can expertise be developed through deliberate practise?
doing tasks at an appropriate level of difficulty
being given informative feedback about performance
having adequate chances to repeat the task
having an opportunity to correct errors
what supports the nature explanation of how to become an expert?
genes!
correlations between specific alleles and performance in certain areas such as athletic performance
identical twins who varies massively in music practice did not perform massively differently in tests of music aptitude
how do skill level and deliberate practice correlate?
the higher the skill level, the higher the average amount of deliberate practice
