Biopsychology Flashcards
1
Q
What is the nervous system?
A
A specialised network of human cells in the human body.
Our primary internal communication system
Based on eletrical/ chemical signals
Acts very quick for shoet amount of time
2
Q
What is the CNS made of?
A
Brain and spinal cord
3
Q
What is the role of the CNS?
A
Processes info from the PNS and sends out signals to the PNS via the spinal cord
4
Q
What is the role of the spinal cord?
A
Reflex actions
5
Q
What is the PNS?
A
Made up of Autonomic and somatic nervous system
6
Q
2 ands
What is the role of the PNS?
A
Gathers information and sends to the CNS and to receives info from the CNS
7
Q
What is the role of the Somatic nervous system?
A
Govens muscle movement
Responsible for carrying sensory and motor info to and from the spinal cord
8
Q
Is the somatic nervous system under conscious or unconscious control?
A
Conscious- as receives signals via motor neurons from brain to initiate skeletal muscles
9
Q
What is the role of the autonomic nervous system?
A
Governs vital functions-breathing, heart rate, digestion
10
Q
Is the autonomic nervous system under conscious or unconscious control?
A
Unconscious control-automatic
11
Q
What is the endocrine system?
A
One of the body’s major info system that instructs glands to release hormones into bloodstream. These can be carried to larger organs, and will affect any cell in the body that has a receptor for that particular hormone. Because of this the endocrine responses are slower then NS but its effects last longer
12
Q
Describe the Pineal Gland
A
Involved in our circadian s/w cycle, produces melatonin and serotin to keep us drowsy/ awake
13
Q
Describe the Adrenal Medulla
A
Involved in the sympathetic state, above the kidneys.
Releases adrenaline
14
Q
Describe the thyroid gland
A
Located in the neck
Releases hormone thyroxine, that affects metabolic rate.
15
Q
What is the role of the nervous system
A
To collect, process and respond to information in the environment
To coordinate the working of different muscles and cells
16
Q
What is the function of Sensory neurons?
A
Carry messages from the PNS to the CNS.
17
Q
What is the structure of a sensory neuron?
A
Found in PNS
Long dendrites, short axons
18
Q
What is the function of Relay neurons?
A
These connect sensory neurons to motor or other relay neurons
19
Q
What is the structure of a Relay neuron?
A
Found in CNS
Short dendrites, short axon
20
Q
What is the function of motor neurons?
A
These connect CNS to effectors (muscles/glands)
21
Q
What is the structure of a motor neuron?
A
Short dendrites, long axon
Found in PNS
22
Q
Describe the reflax action that would occur after touching a hot pan.
A
Heat detected in skin receptors in hand, the signal is sent via sensory neurons (in PNS) to the CNS). The signal is passed onto relay neurons in the spinal cord. Once in the spine the signal is immediately sent out of the CNS via the relay neurons to the motor neurons (PNS). The motor neurons then connect to muscles to initiate hand movement off the pan.
23
Q
Outline the process of synaptic transmittion
A
An electrical impulse travels along the axon of the transmitting neurone
This triggers the nerve-endings on the pre-synaptic neuron to release neurotransmitgters from vesicles
These chemicals diffuse across the synapse and bind to receptor sites on the membrane of the post-synaptic neuron
The receptor molecules on the post-synaptic neuron bind only to specific chemicals released from the first neuron. This stimulates the post neuron to transmit the electrical impulse.
The neurotransmitter is reabsorbed in the vesicles of the pre-synaptic neuron after it has performed its function of transmitting a neuronl impulse.
24
Q
What is meant by excitatory?
A
When a neurotransmitter increases the positive charge of the post synaptic neuron. This increases the likelihood that the post-synaptic neuron will fire.
25
What is meant by inhibitory?
When a neurotransmitter increases the negative charge of the post-synaptic neuron. This decrease the likelihood that the neuron will fire.
26
Name an excitoray neurotransmitter
Adrenaline
27
Explain summation of charge
The total charge on the post-synaptic neuron. This excitary + inhibtory influences are summed: If the net effect on the post-synaptic neuron is inhibitory, the neuron won't fire. If the net effect is excitorty, the neuron will fire.
Therefore the AP of the post-synaptioc neuron is only triggered if the sum of the E+I signals at any one time reaches the threshold.
28
Name a inhibitory neurotransmitter
Serotonin
29
Describe what is meant by an action potential
When a neuron is in a resting state the inside of the cell is negatively charged. When a neuron becomes actived by a stimulus the inside of the cell becomes positively charged for a spilt sec causing an ap occur
30
Why are action potentials unidirectional?
1. Synaptic vescicles containing neurotransmitters are only presnt on presynaptic membrane
2. receptors for neurotransmitter only on post-synaptic
3. Can only diffuse from high to low concentration (only pre-->post)
31
Describe an EEG
a record of the tiny eletrical impulses produced by the brains activity. It works by measuring the eltrical activity in the brain via electrodes that are fixed to an individuals scalp using a skull cap. The scan recording represents the brains wave pattern that are generated from the action of thousands of neurons providing an overall account of brain activity.
32
What is a strength of an EEG? (AO3)
High practical value, used to diagnose epilepsy/sleep disorders
33
What is a limitation of an EEG? (AO3)
EEG signal not useful in pinpointing the exact source of neural activity, doesn't allow researcher to distinguish between activities originating in different but adjacent locations- low spatial resolution
34
Describe an ERP
The electrophysical response of the brain to specific sensory, cognitive or motor event that can be isolated through the statistical analysis of an EEG. ERPs emerge only after many individual presentations of the stimulus of intrest are averaged together
35
What is a strength of an ERP (AO3)?
Cancels out noise + enhances the voltage response to the stimulus making it out clearly from the averaged out background
36
What is a limitation of an ERP (AO3)?
Lack of standardisation, methodogly differs between research studies so hard to confirm findings
37
Describe an FMRI
A method used to measure brain activity while s person is performing a task. It works by detecting the changes in blood oxygenation + flow that occurs as a result of neural activity in specific parts of the brain. When a brain area is more active it consumes more O2 + to meet this increased need, blood flow is redirected to the active area(haemodynamic response) allowing researches to detect specific brain regions.
38
What is a strength of a FMRI scan? (AO3)
Non-invasive, risk free, no radiation
39
What is a limitation of a FMRI scan(AO3)?
Poor temporal resolution due to 5 second time lag behind image on screen +initial firing of neural activity
40
Describe Post-mortem Examinations
The brain is analysed after death to determine whether certain observed behaviour during the persons lifetime can be linked to structural abnormalities in the brain when compared to a neurotypical. Carried out in a typical cases, may measure/ weigh/ look under microscope
41
What is a limitation of Post-mortem Examination(AO3)?
Issues with cause and effect as any observed damage cant be determined conclusively as a cause of any deficits
42
What is a strength of Post-mortem Examinations(AO3)?
Vital for early understanding of the brain-Broca/ Wernicke established links relaying on the method
43
What are biological rythms?
Distinct pattens of changes in the body activity that conforms to cyclical time periods
44
What is an ultradian rhythm?
a type of biological rhythm with a frequency of more than one in 24hours
Sleep cycle
45
What is an infradian rhythm?
A type of biological rhythm with a frequency of less then one cycle in 24hrs.
SAD
46
What are exogenous zeitgebers?
external cues in the environment that may affect or entrain our biological rhythms
47
What are endogenous pacemakers?
our internal body clocks that regulate many of our biological rhythms.
48
What is the sleep wake cycle?
a daily cycle of biological activity based on a 24hour period that is influenced by regular variations in the environment.
49
What is a circadian rhythm?
a type of biological rhythms, subject to a 24hours cycle, which regulates a number of body processes such as the s/w cycle and changes in core temperatures
50
Describe the SCN
The main endogenous peacemarker for the s/w cycle. This is a small group of cells located in the hypothalumus, lieing just above the optic chaism, which is part of the neural pathway connecting the retina of the eye via the optic nerves to the visual area of the cerebal cortext. The SCN reicieves info about light from the optic chaism, even when the eyelids are closed.
The SCN is connected to the pineal gland via a neural pathway; when the pineal gland is activated by the SCN it produces melatonin, Which causes drowsiness. This continues to be emitted, after enough sleep/ becomes light the pathway from the SCN to the pineal gland inhibits melatonin and secretes serotonin.
51
Explain entrainment of exogenous zeitgebers
If there is a shift in external cues, like travelling across time zones, the s/w cycle becomes aligned to new cues bc the SCN is reset. In the period whilst this is occurring they are likely to feel jet jagged.
52
Describe exogenous zeitgebers for the s/w cycle
Light is the dominant time cue for circadian rhythms. Light influences our internal clock through specialised light sensitive cells in the retain of our eyes. These cells connect to the SCN via optic nerves. So although the s/w cycle exists without light, it influences it.
53
What does Siffre research tell us about exogenous pacemakers? (AO3)
That they are still needed to entrain his SCN to the 24hours in a day in the s/w cycle, but that EP is more influential in regulating the cycle then EZ.
54
Describe Siffre's cave study (AO1)
Siffre spent 6 months living in an underground cave in texas-deprived of all external time cues like natural light the time, & sound to study the effects on his own biological rhythm. Reported physiological and psycological impact (body temp/cognitive functioning)
Found cycle stretched to 25hrs.
55
What does Siffre research tell us about endogenous pacemakers? (AO3)
Demonstrates that the SCN is more powerful then exogenous zeitgebers as even in the absence of light the EP maintained a constant s/w cycle, but free ran to 25hours.
56
Describe Aschroff + Wever study (AO1)
Group of ppts spent 4 weeks in ww2 bunkers deprived of light and external time cues. Measured s/w cycle. All but 1 displayed 24-25hrs, 1 stretched to 29hours.
57
What does Aschroff and Wever tell us about endogenous pacemakers (AO3)
Actively demonstrates how the SCN maintained a constant s/w cycle even in the absance of light, as biologically deterministic. As all free ran over 24hrs suggests s/w cycle may be slightly more then 24hrs but is entrained by EZ to the 24hrs in the day.
58
What does Aschroff and Wever tell us about exogenous zeitgebers? (AO3)
All need EZ to entrain to 24hours, however are indivdual differences a some may reliey heavily on EZ to entrain SCN if their circadian rhythm is more likely to extend beyond 24hours.
59
What is a strength of S/W cycle (AO3)?
Improves efficacy of treatments as they can be adminestered in a way that works best with their biological rythm e.g aspirn best taken at night as most heart attacks happen in the morning.
Provides an understanding of adverse consequences that occur when s/w cycle is disrupted ie. shift workers poor concentration. Very valuable to employers to ensure max productivity by using synchronisation methods to help workers.
60
Describe the menstrual cycle
A 28-day cycle in which raising levels of oestrogen causes the ovary to develop an egg and release it(ovulation). After ovulation, progesterone helps the womb lining to grow thicker, reading the womb for pregnancy. If pregnancy doesn't occur, the egg is absorbed into the body, the womb lining comes away and leaves the body.
61
What is the endogenous pacemaker in the menstrual cycle?
The hypothalamus
62
What are the exogenous zeitgebers in the menstrual cycle?
Diet, other women, stress
63
Describe Stern & Mcclintok study (AO1)
29 women with a history of irregular periods. Samples of pheromones were gathered from 9 of the women at differnt stages in their menstraul cycle, via a cotton pad under their armpit for 8 hours. On day 1, pads from the start of the menstraul cycle were applied to upper lips of all 20 women. Day 2, given day 2.
68% women expeirenced changes to cycle which brought them closer to doner cycle.
64
What does Mcclintok research tell us about pacemarkers (AO3)?
Suggests the pheromones entrained a new cycle in the women. 32% seemingly not affected, EZ must have a big impact.
(EVOLUTIONARY BETTER)
65
Describe seasonal affective disorder
A type of infradian rhythm know as circannual rhythm as it is subject to a yearly cycle. Symptoms are triggered in the winter months when daylight hours are shorter, the main ones being persistent low mood, general lack of interest and lack of interest in life.
66
Explain seasonal affective disorder
During the night the pineal gland secretes melatonin until their is an increase of light in the morning. During winter the lack of light means secretion process continues for longer, having a knock on effect on the production of serotonin, so accumulative serotonin levels depreciate.
67
What is a strength for SAD (AO3)?
Understanding its biological cause has led to the development of phototherapy as a treatment. A light box stimulates very strong light to reset the body's internal clock. 80% found effective, suggesting light is the EZ causing SAD
68
What is a limitation of SAD(AO3)?
May not be because of light, could also be the change in social setting (less)
69
Describe stage 1 & 2 of the sleep cycle
Light sleep, easily woken, lots of brain activity
Brain waves are high in frequency, short amplitude.
Alpha waves. In stage 2, alpha waves continue but their are occasional random changes in patten called sleep spindles
70
Describe stages 3 + 4 of the sleep cycle
Slow wave sleep
This is deep sleep in which the brain is flushed with cerebal spinal fluid to clean neurnal debreie.
Delta waves, lower frequency and high amplitude
Most restorative
71
Describe Dement Keieitman research (AO3)
First reasearches to use an EEG to measure sleep and determine the distinic stages, and discover REM during dreaming.
V. high value as paved the way for all future research investigating sleep, first to validate stages and develop a scientific method for measuring and comparing individuals.
72
Describe stage 5 of the sleep cycle
Body is paralysed yet brain activity closely resembles the awake brain.
High frequency low amplitude
Theta waves
REM, dreams most likely happen which is the spontaneous firing of neurons in the pons
High level neural activity
As the sleep progresses, more time is spent in REM per cycle
Duration of REM increases throughout the night
73
What is the sleep cycle?
An ultradian rhythm, in which 5 stages of sleep have been identified. Altogether span 90mins, 5 cycle a night. Each stage is characterised by a different level of brainwave activity, which is validated by an EEG.
74
What is a strength of sleep cycle (AO3)?
Can identify what 'normal' sleep looks like so useful when determining issue. Led to development of sleep tracker apps/watches to determine best time to wake up i.e not in the middle of REM
75
Describe DeCoursy et al. study
Destroyed the SCN in 30 chipmunk brains, then released them into their natural habitat and observed them for 80 days.
Found many were killed by predators as they were awake when most vulnerable to attack when should have been sleeping) and s/w cycle differed.
76
What does DeCoursey et al research tell us about pacemakers (AO3)?
Demonstrated that without the SCN the chipmunks experienced a depilation of sleep/ wake cycle, so EP more powerful as without it many couldn't function and died.
EZ are not efficient enough to regulate the s/w cycle
Research focuses on separating effects of EZ and EP however in real life work together
77
Describe Campbell and Murphy research
Woke 15ppts at various times by shinning a touch on the back of their knees. Light receptors sent the signal to the SCN. It was found that ppts s/w cycle deviated by up to 3hours
78
What does Campbell and Murphy's research tell us about pacemakers (AO3)?
Ep more complex then SCN as could affect the s/w cycle with skin receptors. Peripheral oscillators can also physiologically affect the s/w rhythm.
Exposure to ez of light progressively entrained new s/w cycle EZ of light detected by skin receptors.
79
What is lateralisation?
The notion that different hemispheres have specific functions
80
What is localisation?
Specific brain regions have specific functions, these may nor may not be lateralised in one hemisphere
81
What does the holistic theory suggest about brain function?
That there are multiple brain regions that are responsible for multiple functions, for example many brain regions are involved with language
82
Describe the motor area
Frontal lobe,
controls voluntary movement, damage here may result in loss of control over fine movements
83
Describe Broca'[s area
Frontal lobe, left hemisphere
Responsible for speech production
Damage to this area results in Broca's aphasia, which is characterised by speech that is slow, laborious and lacking in fluency.
84
Describe the auditory area
Temporal lobe
Concerned with the analysis of speech-based information
85
Describe Wernicke's area
Left temporal lobe
Responsible for language comprehension.
People with damage to this area experience Wernicke's aphasia in which they have no problem producing language but have difficulties understanding it, so that their speech is fluent but meaningless
86
Describe the Visual area
Occipital lobe
Receives and processes visual information
Each eye sends info from the RVF to the LVC , and the LVF to RVC.
87
Describe the Somatosensory area
Parietal lobe
Processes sensory information such as touch/pain
Separated from the motor area by a 'valley' called the central sulcus
88
Describe the frontal lobe
Motor cortex + Brocas Controls personality, inhibition, descion making planning
Low activity in pre-frontal cortex of criminals.
Phineas cage support personality localised to frontal lobe
89
Describe the Occiptual lobe
Processes visual info, recognising shapes + colours.
Contains primary visual cortex, info gets to occipital lobe as passes via the optic chiasm, then processed in the occipital lobe at the back of the brain
90
Describe the temporal lobe
2 temporal lobe in the brain, located by the ears.
Hearing-auditory cortex
Language-aphasias: Wernicke's area
Memory
91
What are the benefits in understanding how the brain is localised? (AO3) ❤️
The brain has now been mapped to identify the localised brain regions-this is important to brain surgeons as they know now which brain region are vital/ which can be removed with little impact on function. Knowledge has improved surgery to avoid further damage
92
What is evidence for localisation of function (AO3)
Evidence to support localisation: Buckner + Peterson used PET scans and revaules semantic
+ episodic memories reside in different parts of the prefrontal cortex, conforming localised areas for everyday behaviours. In using object methods for measuring brain activity, sound scientific evidence demonstrates many brain functions are localised. High validity, Clive wearing damage hippocampus then benefits
93
What is evidence for holism theory of localisation?
Lashelys rat research suggest a more holistic function rather then localastioed brain regions. She trained rats to find their way through a maze, then removed 10-50% of the cerebral cortices of the rats and found they were still able to remember their route despite the size or location of their lesions. This suggest that memory isnt localised and must be located throughout the cortex
In addition a recent review by Dick + Tremblay found an updated view of hollistic processing in when it comes to language, as only 2 % of modern researches still believe Broca and Wernicke's area to be responsible.
The brain is clearly capable of plasticity so a fixed localised view is clearly not a complete view.
94
What is plasticity?
The brains tendency to change and adapt as a result of experience and new learning. This generally involves the growth of new connections
95
Describe plasticity as we age
During infancy, brain experiences a rapid growth in the no. of connections it has, reaching 15,000 per neuron at 2-3yrs. this is 2x in adult brain. As we age the brain undergoes synaptic pruning
96
What is synaptic pruning?
Connections not used are deleted and frequently used connections are strengthened Once thought adult brain not capable of changes but now know synaptic pruning enables lifelong plastic.
97
When does plasticity occur?
Demands of the environment/ new learning
Aftermath of a trauma/ accident/ operation gone wrong
98
Describe Maguire et al. research into plasticity
Studied the brains of London taxi drivers and found significantly more volume of grey matter in the posterior hippocampus then in a matched (on age) control group . This part of the brain is associated with development of spacial and navagational skills. London taxi drivers must take a complex test called the knowledge, which asses recall of city streets. Maguire found that the learning experience altered the structure of the taxi drivers brain. Also found longer taxi driver=more prounced structural difference.
99
What evidence is there to support plasticity? (AO3)
Maguires taxi driver study found higher volume and density in the posterior hippocampus compared to non-taxi drivers. It was suggested that their neurons had re-distrubted in response to the enviromental demand of studying for the knowledge (evidence for plasticity). Also found a
+ve correlation between volume and length of time they were a taxi driver-thus suggesting that the higher the demand on their memory/ spatial navigation, the more evidence of plasticity. This provides support for the brain to change in response to a specific environmental demand involving memory and learning.
This is further supported by Dragonskis research showing neuranal changes in the posterior hippocampus and parietal lobe in medical students before + after studying for exams over a 3-month period. This demonstrates plasticity occurring in the brain in response to environmental learning demandsin adults.
100
What is functional recovery?
A form of plasticity, the brains ability to redistribute/transfer functions usually performed by a damaged area, to other, undamaged areas.
101
What is spontaneous recovery?
When a heathly part of the brain takes over the damaged parts function very quickly after tramua, and then slows down after severval weeks.
102
What may be needed to increase functional recovery?
Rehabilitative therapy
103
What happens to the brain during functional recovery?
Rewire + reorganise itself by forming new synaptic connections close to the area of damage.
Secondary neural pathways that would not be typically used are unmasked to enable functioning
Structural changes
104
What is axonal sprouting?
A structural change in recovery
the growth of new nerve endings which connect with other undamaged nerve cells to form new neural pathways.
105
What is denervation super sensitivity.
Structual change in functional recovery
When axons that do a similar job become aroused to a higher level to compensate for the ones that are lost
106
What is recriuitment of homologus areas?
A structural change of neural plasticity
On the opposite side of the brain, so specific task can still be performed
107
What is a limitation of functional recovery? (AO3)
Recovery of the brain can led to maladaptive consequences for example prolonged drug use may cause brain adaptation which leads to poorer cognitive functioning and increased risk of demention. Also 60-80% amputees experienced phantom leg syndrome, an unpleasant sensation due to cortical reorganisation in the somatosensory cortex. This suggest the brains ability to adapt to change many not always be beneficial, however knowledge of this can help treat individuals neurologically and can help understand the negative impact of lifestyle choices.
108
What is a strength of functional recovery? (AO3)
High pratical application- we now know that damaged areas of the brain doesn't mean it's function is diminished. Spontaneous recovery tends to slow down after a few weeks, so physical therapy may be required to maintain improvements. Neurorehabilitation which uses motor therapy and electrical stimulation of the brain to counter the -ve effects + deficits in motor + cognitive functions following accidents/injuries/ strokes. This demonstrates the positive application of research in this area to help improve the cognitive functions of people suffering from injuries.
109
What is hemispheric lateralisation?
The idea thAt the two halves of the brain are functionally different and that certain mental processes and behaviours are mainly controlled by one hemisphere rather then the other as in the example of language, which is localised as well as lateralised.
110
Why is language lateralised?
two main centres are only in the LH- Wernicke's in left temporal Broca's in left frontal lobe, so language is performed by one hemisphere rather then the other
111
What is the function of the RH?
Only produce rudimentary words and phrases but contributes emotional context to what is being said.
LH=analyser
RH=synthesis
112
How is motor cortext lateralised?
Its not as appears in both hemispheres. The brain is cross-wired (contralateral wiring). The RH controls movement on the left side of the body and LH controls movement on the right.
113
What is a split brain operation?
Involves severing the connections between the RH and LH , mainly the corpus callosum. Used to reduce epilepsy, to stop the excessive electrical activity.
Split brain research studies how the hemispheres function when they can't communicate with each other
114
Outline Sperry's Research
11 people who had had their corpus callosum severed. A picture was flashed to either the left or right visual field. If flashed to the LVF it was processed by the RH, said they say nothing and drawn by the left hand. It it was flashed to the RVF it was processed by the LH, they could say what they saw as Brocas, and drawn by the right hand. Despite alll being Right handed, pictures drawn by the Left hand were better, showing the RH is better at spacial tasks.
115
How was Sperry's research standardised? (AO3)
Control group of 11 people who had no epilepsy
Standardised procedure, high control of stimulus + time
Stare at given point whilst one eye was blindfolded.
Image flashed only for 1/10th of a second, so ppts couldn't move eyes across the image
116
Why is it important that Sperry's ppts couldn't move their eyes across the image?
If more then 1/10th of a sec the persons eye would move across so that both L+R visual field would process the stimulus-this would mean that both hemispheres could be aware of the stimulus seen as visual info crosses over to the opposite hemisphere via the optic chiasm + not the corpus callosum-which would invalidate the experiment.
117
Limitation Split-brain research (AO3)?
Over simplify the RH, much more cognitive functions then first thought as does comprehend language, has separate schema, individual memory.
Lateralisation of the hemispheres over emphasised, right still very functional and can do a lot of what left can.
In real life, split-brain patients process the world using both visual fields looking for longer then 1/10th of a sec, so both hemispheres are aware of the visual world via the optic chiasm, so low external reliability.
Can't generalise the findings to support the nomothetic theory of lateralisation of function as using an atypical brain so can't compare to neurotypicals. Control group should have had epilepsy and corpus callosum
