biopsychology Flashcards
1
Q
name the components of the nervous system
A
divides into central nervous system (CNS) and peripheral nervous system (PNS).
CNS divides into brain and spinal cord
PNS divides into autonomic nervous system (ANS) and somatic nervous system (SNS).
ANS divides into the sympathetic and parasympathetic nervous systems.
2
Q
describe the role of the somatic nervous system
A
consists of sensory and motor neurones to carry senseroy and motor information to and from the CNS.
enables reflex actions.
3
Q
what are the roles of the sympathetic and parasympathetic nervous systems?
A
sympathetic - involved in fight/ flight
parasympathetic -involved in ‘rest and digest’ functions
4
Q
name the parts of a typical neurone
A
- dendrites
- cell body
- nucleus
- axon
- myelinated sheath
- nodes of ranvier
- axon terminal
5
Q
describe the structure and function of a neuron
A
- neurones enable communication within the nervous system.
- The cell body (soma) contains the genetic material (in nucleus)
- branch like dendrites extend from the cell body
- dendrites carry functional information towards the cell body
- dendrites can receive info from other neurones
- axons carry messages away from the cell body
- axons can be myelinated to increase speed of nerve transmission
- nodes of ranvier allow for saltatory conduction
- terminal boutons are at the end of axons and make the synaptic connections with other cells
- axon terminal contain neurotransmitters.
6
Q
describe the divisions of the nervous system
A
- the nervous system is divided into the central and peripheral nervous systems
- the CNS comprises of the brain and spinal cord
- The PNS divides into the somatic nervous system and autonomic nervous system.
- somatic nervous system consists of sensory and motor neurones to carry sensory and motor information to and from the CNS and enables reflex actions
- the ANS acts involuntarily
- ANS divides into the sympathetic and parasympathetic nervous systems.
- sympathetic nervous system involved in fight or flight response
- parasympathetic nervous system involved in ‘rest and digest’ functions.
7
Q
what is the function of the sensory neurone?
A
receives information from the receptors (e.g. skin) and sends the info towards the relay neurone in the brain
from receptors to brain
8
Q
what is the function of the relay neurone?
A
takes information from the sensory neurone and passes it around the brain, towards the appropriate motor neurons
in the brain
9
Q
what is the function of the motor neurones?
A
receives info from the relay neurones and passes down to the effectors to make muscle movements e.g. dropping a pan.
from brain to muscles
10
Q
which neurone goes towards the brain?
A
sensory
11
Q
which neurone goes away from the brain?
A
motor
12
Q
which neurone is in the CNS?
A
relay
13
Q
outline synaptic transmission
A
- an action potential comes down from the axon
- stimulates calcium ions and the production of vesicles which contains neurotransmitters.
- the vesicles release neurotransmitters which diffuse across synaptic gap from an area of high conc to low.
- neurotransmitters bind to complementary receptors in post synaptic membrane, allowing sodium ions to move into post synapse
- this creates an action potential in the post synapse
- neurotransmitters are released and taken back into presynapse through a reuptake process and enzymes break down any remaining neurotransmitters in presynapse and synaptic gap
14
Q
Zapurpain acts like an inhibitory transmitter at the synapse.
explain how Zurpurpain might affect the process of synaptic transmission through inhibition
A
Zapurpain mimics the effects of inhibitory neurotransmitters, stimulation of postsynaptic receptors by an inhibitory neurotransmitter result in inhibition (hyperpolarisation) of the post synaptic membrane.
when an inhibitory neurotransmitter binds to postsynaptic receptors, it makes the post synaptic cell less likely to fire (IPSP)
summation- if inhibitory inputs are higher than excitatory they can cancel out excitation and inhibit an action potential occurring (Zapurpain would decrease overall activity)
- Zapurpain would make the post-synaptic cell less likely to fire
15
Q
what does an inhibitory neurotransmitter (IPSP) do?
A
- slows down the firing rate on the post synapse as it increases the threshold at which an action potential can be reached at the post synapse (hyperpolarisation)
16
Q
what does an excitatory neurotransmitter (EPSP) do?
A
speeds up the firing rate at the post synapse as it decreases the threshold at which an AP can be reached at post synapse. - depolarisation
17
Q
what is summation? name and describe the two types
A
the number of IPSP and EPSP is calculated.
more IPSP = inhibitory
more EPSP = excitatory
spacial summation - many neurones into one neurone
temporal summation - one neuron into one neurone
18
Q
outline the function of the endocrine system
A
regulate cells or organs within the body and control physiological processes by releasing hormones from glands into the bloodstream.
19
Q
what is the function of the thyroid gland?
A
releases thyroxine which increases metabolism.
20
Q
what is the function of the pineal gland?
A
releases melatonin which regulates the sleep-wake cycle
21
Q
what’s the function of the pituitary gland?
A
master gland that controls all other glands release of hormone
Also releases oxytocin which increases binding or stimulates LH/FHS
22
Q
what is the function of the adrenal gland?
A
releases adrenaline which controls the sympathetic responses to fight/flight
23
Q
what is the function of the pancreas?
A
releases insulin to maintain blood glucose levels.
24
Q
A01 for fight or flight
A
sympathetic pathway
- acute stress = ‘threat’ detected by hypothalamus
- noradrenaline is secreted, stimulating adrenal medulla
- adrenal medulla secretes adrenaline
- increases heart and breathing rate, sweating and stops digestion. diverts blood from surface of skin.
Parasympathetic pathway
once ‘threat’/ stressor has passed the PSP decreases heart and breathing rate, blood pressure and turns on digestion (making people hungry/ thirsty)
25
outline the evaluation for fight or flight (FoF)
**_reductionist_**
- **Ev** - freeze effect - avoiding confrontation, hypervigilant to threat, decide best course of action
- **Ex** - humans have cognition to problem solve, not just instinctive bio response to threat
- **L** - But ‘freeze’ still evolutionary survival instinct - playing dead to ensure survival.
**_gender differences__**
- **Ev** - Taylor et al -
Women = ‘tend and befriend’
Men = FoF.
women more likely to protect offspring and form alliances with other women.
- **Ex** - Oestrogen enhances the effects of oxytocin (‘love hormone’), increasing nurturing beh’s.
testosterone inhibits it, and linked to aggression (fight).
- **L** - Some males tend and befriend - seek out others when stressed for social support. Gender biased to assume aggression from FoF only male- alpha bias.
**_outdated explanation_**
- **Ev** - Modern times - stressors = chronic + long lasting (e.g. lack of money, job stress) rather than short term with ancestors.
- **Ex** - FoF adapted for survival. Modern stressors can’t be solved through this basic bio system. Ignores role of cognition to deal with modern stress.
- **L** - do still use FoF but isn’t maladaptive - can create health problems (stroke, heart attack). So if FoF evolutionary, should devolve over time.
26
what is the role of the frontal lobe and what areas does it contain?
problem solving and decision making
contains **Broca’s area** - speech production
and **Motor cortex**- voluntary movements
27
what area does the parietal lobe contain and what is its function?
**somatosensory area** - receives sensory info from skin to produce sensations related to pressure, pain, temperature etc.
28
what areas are in the temporal lobe and what are there functions
**Wernicke’s area** - language processing/comprehension
**auditory area/cortext** - analyses and processes acoustic info (e.g. volume, temp and pitch)
29
what area is in the Occipital lobe and what is its function?
**visual area** - receives and processes visual info (colours, shapes, movement)
30
outline evaluation for localisation of function in the brain
**_research support from case study_**
-**Ev** - Tan - could only say ‘tan, tan’ - lesion in Broca’s area. could do other functions such as maths
-**Ex** - Therefore Broca’s area is localised in its function for speech production. He had language comprehension and mathematical ability, so brain lobes have specific functions.
-**L** - but unique case study, can’t see function whilst alive - only after in post mortem.
correlational - may not be precise damage to Broca’s - modern fMRI scans shows other areas involved in speech production, so maybe not as localised as thought.
**_gender differences_**
-**Ev** - women have a larger Broca’s and Wernicke’s area than men
- **Ex** - not all individuals brains are localised in the same way - not innate, created by env.
Brian becomes more localised due to plasticity - primary socialisation (girls = language dev, boys = active playing - spatial areas)
-**L** - doesn’t criticise theory - specialised areas of brain are responsible for certain functions, but specialism = adaptive to a persons environment/ nurture.
**_brain only localised for simplistic functions_**
-**Ev**- higher mental functions, e.g. decision making and problem solving aren’t localised. Simpler functions such as language are more localised.
-**Ex** - this suggests brain isn’t intended to be localised and all parts of brain are used equally for a function.
more important to consider how diff areas work together rather than sep
-**L** - summary: useful in understanding basic localised functions of brain.
but unless we fully understand how areas communicate, we can’t understand complex mental processes e.g. memory, perception, attention.
This can be done through use of new technology (fMRI scans)
31
what is the left hemisphere of the brain responsible for?
language, analysis, problem solving
32
what is the right hemisphere of the brain responsible for?
Object and face recognition, creativity, spacial comprehension.
33
what is the corpus callosum?
bundle of neuronal fibres connecting the two hemispheres
34
outline Sperry’s study on lateralisation, including the results
- 11 ppl with epilepsy had corpus callosum cut and 11 ‘normal’ ppl with intact corpus callosum
- controls = hands in box, blindfolded one eye.
- words/ objects/ faces flashed onto a screen for 1/10th of a second, they fixated on a point in middle of screen.
results:
- **language**: LH and RVF - could say word
RH and LVF couldn’t say word
- **object recognition:** RH and LVF could draw object well
LH and RVF - drew object poorly
- **face recognition:** RH and LVF - could match face
LH and RFV - couldn’t match face correctly
35
outline evaluation for lateralisation
**_highly scientific research support_**
-**Ev** - lots of controls, e.g. 1/10th sec, hands in box, blindfolded in one eye, control group
- **Ex** - strong causation, could only be due to the hemisphere that causes the issue with the object/ face rec/ language.
-**L** - but sample has individual differences, e.g. in severity of epilepsy prior to surgery. Also the epilepsy could have changed the localisation of functions of their brain, therefore it doesn’t account for plasticity and isn’t generalisable.
**_further research support for lateralisation_**
- **Ev** - Roger’s et al: chickens - brain lateralisation associated with enhanced ability to perform two tasks simultaneously: finding food and being vigilant for predators.
- **Ex** - Proves lateralisation is evolutionary and necessary for survival and that all mammals have this function.
-**L** - however, humans aren’t prey but predators and hence de-lateralisation is more advantageous- need to be able to use all of our brains for complex functions.
**_lateralisation changes with age_**
-**Ev** - over age of 25, brain becomes more de-lateralised.
-**Ex** - due to more life experience and plasticity both hemispheres of the brain take on the functions.
It’s simplistic to assume each hemisphere only does one function, more complex functions, e.g. problem solving needs both hemispheres to function together, not independently.
- **L** - but brain begins lateralised and not certain if de-lateralisation is negative due to decay with age or if the brain has improved by it.
36
what is structural plasticity?
brain areas changing in shape/ structure
37
what is functional plasticity?
brain areas changing function (one area of brain can compensate for a damaged area by taking over their functions)
38
name the three ways in which plasticity can work
- axonal sprouting
- neuronal unmasking
- recruitment of homologous areas
39
what is axonal sprouting?
creating a new axon and axon terminal from the existing damaged one
40
what is neuronal unmasking?
creating a new axon from the cell body
41
what is recruitment of homologous areas?
the equal but opposite area of the brain in other hemisphere takes on the particular function.
e.g. if broca’s area damaged on left, right sided equivalent would take on function.
42
outline Maguire’s study on plasticity.
**sample**
- 16 London taxi drivers (who’d undergone the ‘knowledge test’) leant a map of London.
- 50 non-taxi drivers
matched pairs design - males, RH
**procedure**
- PET scan of hippocampus (memory)
- voxel pixel counting
- double blind study (researcher counting pixels didn’t know if taxi or non so no researcher bias)
**results**
- Posterior hippocampus larger in taxi drivers than non (structural)
- Posterior hippocampus had taken over some of anterior hippocampus in London taxi drivers (functional)
43
outline evaluation for Plasticity in the brain:
**_Criticism of Maguire’s research support_**
-**Ev** - sample bias (androcentric) and no before and after the knowledge test.
-**Ex** - can’t be certain if plasticity is same in women, or if ‘the knowledge test’ cause structural plasticity, or if they passed the test as their posterior hipp was already larger, hence better at remembering maps.
**_But, Maguire did further research to overcome criticism_**
-**Ev** - Same study but compared hipp before and after knowledge test.
Result: Posterior hipp did increase.
-**Ex** - learning mental map of london structurally and functionally changed their brains.
so brains do have plasticity and continue to develop as we learn.
**_but individual differences in level of plasticity ppl have_**
- **Ev** - gender - women have more plasticity in Broca’s + Wenicke’s area than men.
Education- undergraduate students that suffered brain damage had more plasticity than those without any qualifications (recovered more function)
Age - over 40 years plasticity decreases. takes longer to recover from brain damage.
-**Ex** - so, plasticity dependant on age, gender and education, suggesting it’s both env. and bio.
44
What are the 4 ways of studying the brain?
- post mortem
- fMRI
- EEG
- ERP
45
briefly describe a post mortem
brain is dissected after death and compared to a neurotypical brain.
46
evaluate the use of a post mortem
- high spacial resolution (allows for high level of examination of brain structures down to neuronal level)
- but poor temporal validity (no direct brain activity to see)
- not conducted on living brain so unusual beh in life and damage found is correlational. However, theories are then generated that can be tested.
47
briefly describe an fMRI
detects blood flow in the brain. (more active areas need more blood)
48
evaluate the use of fMRI
- good spacial resolution - precisely identifies active brain regions.
- but poor temporal validity - one image taken every few secs and delay in blood flow after activity.
- non-invasive, safe technique compared to other options such as PET that use radiation.
- but expensive to build and operate and ppt needs to be still.
49
briefly describe an EEG
Uses skull cap and electrodes fixed to scalp to detect neuronal activity.
records general brain activity
50
evaluate the use of EEG’s
- high temporal resolution - measuring brain activity in milliseconds
- low special resolution - gives general readout of brain waves.
- cheaper than fMRI and can be used in experiments where ppt moves.
- used in diagnosing medical conditions such as epilepsy and in sleep research studies.
- portable, non-invasive
51
briefly describe ERP’s
Uses skull cap and electrodes fixed to scalp to detect neuronal activity.
allows research to study how individual cognitive processes take place in brain
52
evaluate the use of ERP’s
- high temporal resolution - ms sampling rate.
- poor spacial resolution
- portable, non-invasive
- useful in showing functioning to a stimulus.
53
outline one difference between the EEG and ERPs
EEG is a recording of general brain activity usually linked to states such as sleep and arousal
whereas, ERPs are elicited by a specific stimulus presented to the participant
54
what are the three types of biological rhythms? give examples
Circadian - 24hr cycle (body temp, sleep wake cycle)
Ultradian - less than 24hrs (eating, sleep stages)
Infradian - more than 24hrs (menstruation)
55
what is an Endogenous pacemakers?
control of biological rhythms is exerted from within (e.g. Suprachiasmatic nucleus (SCN))
56
what are Exogenous Zeitgebers?
control is exerted from outside by environmental stimuli (e.g. exposure to daylight)
57
Explain the Control of the Circadian Rhythm of a sleep/ wake cycle
- lack of light (EZ) is detected by the optic nerve
- the info is passed to the SCN (EP) in the hypothalamus
- The pineal gland then secretes melatonin (sleep hormone) and decreases serotonin
- The person goes to sleep. the cycle then reverses when light (EZ) is detected by the retina
- The SCN in the hypothalamus then stops the pineal gland secreting melatonin and increases serotonin.
- the person awakes and this repeats every 24hrs.
58
outline evaluation for circadian rhythms
**_research to support role of EP’s in circadian rhythms_**
-**Ev** - 30 chipmunks had SCN removed and observed for 80 days. All chipmunks sleep-wake cycle ceased.
By end of study, significant proportion had been killed by weasels.
-**Ev** - The EP is responsible for keeping time to our circadian rhythm and ensures our survival.
-**L** - But humans are apex predators unlike chipmunks. EZ may be more important in humans, as less EP less needed for survival as we pray on other animals. E.g. Light from mobile phones interrupts the circadian rhythm of adolescents, affecting academic performance.
**_research to show EP important in human circadian rhythms_**
-**Ev** - Michael Siffre in cave for 2 months. No EZ - no light, clock, communication to outside world. Only could call out to his team. Found his circadian rhythm stayed at around 24.5hrs.
- **Ex** - EP (SCN) can hold humans to a 24hr circadian rhythm without any EZ. Therefore, our bio clock more
important.
- **L**- But case study of caver who was used to being underground. Was cold and wet, reducing his body temp, increasing sleepiness. So cannot
assume circadian rhythm is purely down to EP when living on the surface of earth.
**_real life application for role of EP_**
-**Ev** - Eskimos in arctic circle have daylight all summer and dark all winter. They maintained a 24hr circadian rhythm.
-**Ex** - Suggests humans don’t need an EZ (e.g. light) to regulate the circadian rhythm. EP = most important factor.
-**L** - But eskimos used blackout curtains during summer months and UV light during winter. Therefore stimulating the EZ to help maintain the circadian rhythm to 24hrs.
59
describe ultradian rhythms in relation to the stages of sleep.
stages 1 + 2 = light sleep (Non-REM)
stages 3 + 4 = deep sleep (Non-REM)
stage 5 = dream (REM) - similar to awake.
- This cycle from active to rest to active happens every 90 mins (hence ultradian)
- Known as Basic rest activity cycle (BRAC)
60
Outline evaluation for ultradian rhythms
**_research support for ultradian rhythms being biologically controlled by EPs_**
-**Ev** - 9 pps stayed in a sleep lab and were woken every time the EEG brainwaves changed, using a doorbell sound. Pps asked to report what they remever. Only recalled dream in REM sleep.
-**Ex** - so, SCN regulates any basic rest activity cycle in the body, such as the sleep stages. We go from active to rest to active every 90 mins which is bio controlled.
-**L** - But small sample of 9 and have been reports of dreaming in stage 4 of sleep (non-REM), so activity isn’t specific to REM sleep.
Also, time taken to go through sleep stages can change depending on env. factors, e.g. mobile phone light.
61
explain infradian rhythms in relation to the menstrual cycle
- Hypothalamus stimulates pituitary gland to release LH and FSH
- LH and FSH stimulate the development of follicle in ovary
- As follicle develops, oestrogen is released from ovaries, suppressing LH and FSH.
- As oestrogen increases the uteral lining, LH and FSH are re stimulated by hypothalamus
- The spike in LH and FSH releases an egg. This causes progesterone to increase, thickening the uteral lining further in preparation for a foetus.
- If the egg isn’t fertilised, progesterone and oestrogen decrease, the uteral lining sheds. This repeats every 28 days approx.
62
outline evaluation for infradian rhythms
**_research support for ultradian rhythms being controlled by EZ’s_**
- **Ev** - Study- collected pheromones (EZ) in the sweat from the armpits of women who were due or ovulating. The sweat was placed on the upper lip of other women. Their menstruation cycle synced to ‘odour donor’.
-**Ex** - so, external factors such as pheromones from other women can alter the infradian menstruation cycle. Hence, EZ play a part in them.
-**L** - But pheromones are bio chemical messengers and syncing the inf. rhythm of menstruation could be considered evolutionary, as it ensures women give birth around the same time so can look after each others children to provide safety in numbers, ensuring a higher survival rate.
