Biopsychology Flashcards
(80 cards)
1
Q
What is the nervous system
A
- a specialised network of cells
- our primary internal communication system
- 2 main functions : to collect,process and repsond to info AND to co-ordinate working of organs and cells
- split into two sub-systems
- the peripheral NS and the Central NS
2
Q
Describe the central nervous system
A
- made up of the brain and the spinal chord
- the brain is the centre of all conscious actions and has an outer layer called the cerebral cortex which is what distinguishes humans from other animals
- spinal chord is an extension of the brain and is responsible for reflex actions
3
Q
Describe the peripheral nervous system
A
- the PNS transmits messages to and from the CNS via millions of neurones
- further subdivided into 2 systems
1. autonomic NS - governs vital functions in body such as heart rate, breathing, digestion, sexual arousal
2. somatic NS - receives information from sensory receptors and controls muscle movement
4
Q
What is the endocrine system?
A
- works alongside the nervous system
- instructs glands to release hormones directly into the bloodstream
5
Q
Describe the actions of glands and hormones
A
- glands are organs responsible for synthesising hormones and releasing them into the bloodstream
- hormones are chemical substances that circulate the bloodstream and only affect target organs
6
Q
Nmae two examples of glands in our body and what they are responsible for
A
THYROID - a gland in our throat responsible for releasing thyroxine
- thyroxine affects cells in the heart and cells throughout the body which affect metabolic rates
PITUITARY - a gland in our brain
- AKA the master gland as it controls the release of hormones from other glands in the body
7
Q
How do the endocrine system and ANS work together in the fight or flight response
A
- when a stressor is perceived, the hypothalmus triggers activity in the sympathetic branch of the ANS
- ANS switches from parasympathetic state to sympathetic state
- adrenaline is release from adrenal medulla in adrenal glands
- causes physiological changes : getting body ready for fight or flght
- once stress passes, parasympathetic NS returns body to resting state
- the PNS works antagonistically to the SNS
- this is an AUTOMATIC response
8
Q
Describe the sympathetic state
A
- heart rate increases
- blood pressure increases
- salivary production inhibited
- digestion inhibited
- pupils dilated
9
Q
Deescribe the parasympathetic state
A
- digestion stimulated
- heart rate decreases
- blood pressure decreases
- pupils constricted
- salivary production continues
10
Q
What is a sensory neurone?
A
- carry messages from PNS to SNS
11
Q
What is a motor neurone?
A
- connected to an effector which brings about a response
12
Q
Describe electrical transmission
A
- The resting potential of a neurone is negative
- when a stimulus activates the neuron, it becomes positively charged for a split second which causes an action potential to occur
- sending an electrical impulse down the axon
13
Q
Describe synaptic transmission
A
- transmission between neurones is known as synaptic transmission
- synapses include the synaptic cleft, pre-synaptic terminal, post-synaptic receptor site
- when the action potential reaches the pre-synaptic terminal, it triggers the release of the neurotransmitter
14
Q
Describe the actions of neurotransmitters
A
- neurotransmitters are chemicals that diffuse across the synaptic cleft
- they are released from the pre-synaptic terminal and they bind to post-synaptics receptor sites
15
Q
Distinguish between excitatory and inhibitory
A
EXCITATORY - increases positive charge of the neuron once taken up by post-synaptic neuron
INHIBITORY - increases the negative charge of the post-synaptic neuron
16
Q
Define localistation of function
A
The theory that different parts of the brain are responsible for different functions
17
Q
What are the four different areas of the brain?
A
Frontal lobe
Parietal lobe
Occipital lobe
Temporal lobe
18
Q
Name the 6 different “areas”
A
19
Q
What is the function of the auditory area (front temporal lobe)
A
- analyses speech-based information
- damage could lead to hearing loss
20
Q
What is the function of Broca’s area (front of frontal lobe)?
A
- responsible for speech production
- damage (Broca’s aphasia) could result in slow, labourious speech that lacks fluency
21
Q
What is the function of the Motor cortex (back of frontal lobe)
A
- responsible for voluntary movements
- damage could cause loss of control over fine movements
22
Q
What is the function of the somatosensory area? ( front of parietal lobe)
A
- resposnsible for processing sensory information
23
Q
What is the function of the visual cortex?
A
- Responsible for processing visual information from visual fields
24
Q
What is the function of Wernicke’s area?
A
- responsible for language comprehension
- wernicke’s aphasia could result in nonsense language being produced
25
localisation strength - CASE STUDY
(+) Phineas Gage - frontal lobe damaged through a metal rod piercing it - still survived but personality changed to quick- temepered and rude etc suggesting that persoanlity and temperament are localised in the frontal lobe
HOWEVER
Case studies don't have a before to compare to so the findings might not be valid and also can't check reliability or generalize
26
Localisation strengths (research evidence)
(+) wealth of evidence supporting localisation - Peterson et al conducted brain scans and found Broca's area to light up during reading tasks and Wernicke's area during listening tasks - suggests these parts of the brain have different functions
27
localisation weaknesses
(-) plasticity supports a holistic view of brain - diff parts of brain can change function
## Footnote
(-) Lashley said that higher cognitive processes are not localised - removed parts (10%-50%) of cortex of mice and put them in maze and it was found no area was proven to be more important - suggests that higher functions like learning arent localised
28
What does Plasticity mean?
- The brain's tendency to change and adapt in response to new learning and experiences
- during infancy we have the most synaptic pathways but as we grow some pathways are not used and thin down as a result
- but some are used more and therefore become stronger
- this is known as synaptic pruning
29
Describe the research done by Maguire et al
- Maguire et al studied the brains of London Cab drivers
- found a significant difference in sizes of the volume of the grey matter in the hippocampus between a control group and the London Cabbies
- the hippocampus is associated with spatial and navigational skills
30
Describe what Functional Recovery means
- its a form of plasticity
- following trauma or injury, unaffected areas of the brain can compensate for the damaged areas of the brain
- neuroscientists say that this happens very quickly after injury but can slow down and so patients have to undergo rehabilitative therapy
31
Describe HOW the brain recovers?
- the braincan rewire and reorganise itself by forming new synaptic connections
- done by:
- axonal spouting - growth of new nerve endings
- reformation of new blood vessels
- recruitment of homolgous areas on opposite hemisphere
32
plasticity + functional recovery strengths
(+) practical application - understanding of processes involved in plasticity contributed to neurorehabilitation - increased understanding of it so it can be used more effectively - increases validity
(+) research evidence from hubel and wiesel - sewed one eye of a kitten shut and anaylsed brain cortical activity - found that the visual cortex associated with the shut eye did not remain idle but processed information from the open eye - shows that cortical remapping does occur
33
plasticity + functional recovery weaknesses
(-) cognitive reserve affects plasticity - found that those with more of educational background are more likely to make a disability free recovery - not universal - is it appropriate to generalise findings from research
(-)brain's ability to reorganise itself can have a maldaptive effect - 60-80% of amputees experience phantom limb syndrome - unpleasant pain and sensation as if the missing limb is still there - thought to be due to cortical reorganisation in the somatosensory area
34
What is hemispheric lateralistion?
- the idea that the two hemispheres of the brain are functionally different
- that certain mental processes and behaviours are controlled by one hemisphere over the other
- for example language is controlled by the left hemisphere
35
What is split-brain research?
- A series of studies conducted by Sperry investigating the effect of the corpus callossum (joins 2 hemispheres together) being removed in epileptic patients
- allowed Sperry and colleagues to see the extent to which the brain is lateralised
36
Describe the procedure of Sperry's split brain research
- he devised a general procedure where the particpant would be flashed an image for example in the right visual field and a different one in the left visual field
- the participants would then be asked to say what they saw in each visual field
- split-brain patients wouldnt be able to describe what they saw in their left visual field ( processed in right hemisphere)
37
Describe the key findings of the "describing what you see" variation
- when a picture was shown to the patients left visual field (this is processed by the right hemisphere) the split-brain patient can't describe what they saw and would instead say "theres nothing there"
38
Describe the key frindings of the "composite words" variation
- 2 parts of a composite word would be shown e.g KEY and RING
- one would be shown to the LVF and one to the RVF
- ones shown to LVF the split-brain patient would say theres nothimg there but would be able to pick out the object from a selection
39
Describe the key findings of the "recognition by touch" variation
- everything is the same as before i.e. the words are shown to them on a screen but this time they had to select an object that's related to the word from a selection hidden behind a screen so they couldn't see them
40
Describe the key findings of the "matching faces" variation
- the right hemisphere is dominant in facial recognition
- when shown different faces to each visual field, ones shown to LVF were consitently picked when asked to choose a face from a series of faces and ones shown to the RVF were consistently ignored
- when composite faces were shown, the side shown to the RVF was verbally described and the side shown to the LVF was chosen out of a selection
41
hemispheric lateralisation strengths
(+) a great bank of research into this - sperrys work especially provided a great wealth of knowledge -e.g the fact that left responsible for analytic and verbal skills and right for our spatial and music - key contribution to our understanding of the brain
(+) methodology had good internal validity bc of the high control implemented- made sure that only the VF he wanted saw what he wanted by flashing image for 0.1 s - which also allowed him to vary different aspects of the experiment for the different variations
42
hemispheric lateralisation weaknesses
(-) only a sample of 11 and all had epileptic history - epilepsy may have influenced brain so results could be bc of the epileptic history not lateralisation - difficult to generalise findings
(-)pop psychology has oversimplified and overstated the difference in function of the two hemispheres as its known as "verbal side" and "non verbal side" where realistically it's not as clean cut as that as the two hemispheres can work together and one can perform action of other if needed -
43
Describe what Post Mortem examinations are
- a technique involving the analysis of a brain following someone's death
- the brains that are usually examined are ones from people who suffered from rare disorders
- these brains are usually compared to neurotypical brains
44
post mortem strengths
(+) anatomical advantage - deeper regions of the brain-
(+) helped deepen our understanding of the brain - Wernicke and Broca both relied on post-mortem examinations for their work on language
45
post mortem weaknesses
(-) consent can be difficult to obtain - HM couldn't give consent due to his memory loss but they still dissected his brain
46
Describe how an EEG works
- these measure electrical activity in the brain by connecting electrodes via a skull cap to the individuals head
- it represents brainwave patterns that are generated from the action of millions of neurones - giving an overall account of brain activity
- can be used as a diagnostic tool as arrhythmic patterns are indicate neurological abnormalities
47
EEG strengths
(+) very high temporal resolution - see things in real-time - esp good for stages of sleep studies
- (+) invaluable as a diagnostic tool - helps diagnose epilepsy - shows its an appropriate way to measure brain activity
48
EEG weaknesses
(-)low spatial resolution- info is received from many neurones can't specify diff but adjacent neurones - not good for cortical specialization
49
Describe ERP
- measures changes in electrical activity using electrodes but with a specific stimulus to see where the activity is from
- using a statistical averaging technique, extraneous brain activity is filtered out leaving only the responses related to a specific stimulus/task
50
ERP strengths
(+) High temporal resolution - real-time activity can be measured - resolution of a millisecond
(+) high specificity- bc of the specific stimuli it makes it better than EEGs
51
ERP weaknesses
(-) with ERP all background noise and extraneous material have to be eliminated - not always easy - reduces appropriateness
(-) lack of standardisation of methodology used between diff research studies is a concern for the reliability of the findings produced - makes it difficult to confirm them
52
- Describe what an fMRI is
- fMRI works by detecting oxygen changes in the brain
- when different parts of the brain work, they require more oxygen so more oxygen has to go to the part of the brain
- this shows which part of the brain is involved in certain mental processes
53
FMRI strengths
(+) non invasive - makes it more appropriate for more people
(+)high spatial resolution - show detail by the millimetre - provide a clear picture of how brain activity is localised
54
FMRI weaknesses
(-) low temporal resolution- 5 second lag between initial neuron activity and image
(-) expensive - limits appropriateness
55
Describe what "circadian rhythms" are
- circadian rhythms are biological rhythms that last for 24 hours
- a common example is the sleep/wake cycle
56
Describe what Siffre did to investigate our sleep/wake cycle
- he lived in a cave for 6 months with no natural light and no clock so he had no clue what time it was
- he ate and slept when he felt like it to see the effect of his "internal body clock" free-running
- his free-running internal body clock settled down to be around 25 hours
- it was concluded that our "natural" sleep/wake cycle may be over 24 hours but exogenous zeitgebers are therefore important in maintaining it a 24 hour cycle
57
Describe Aschoff and Wever's study
- convinced a group of pps to spend 4 weeks in a WWII bunker deprived of natural light
- all but one individual displayed a circadian rhythm of 24-25 hours
58
Describe Folkard et al's study on Circadian rhythms
- studied a group of 12 PPS who lived in a dark cave
- they went to bed when the clock said 11:45 and woke up when the clock said 7:45
- researchers gradually sped up the clock so that the day only lasted 22 hours
- only 1 adjusted comfortably
- shows the strong influence of our internal body clock
59
circadian rhythms strengths
(+)practical application to shift work - shift workers experience a lapse in concentration around 6 am - economical implications - helps managers know how best to manage worker productivity + safety
(+) practical application for drugs - research has shown when its most effective to take drugs- real-life benefits in medical field
60
circadian rhythms weaknesses
(-)studies use small samples - Siffre was only one man and even in Folkard and Aschoff and Wever's studies, small samples were used - not representative of the wider population as those ppl's circadian rhythms may be different to others - Siffre even observed that his ticked much slower at 60 compared to when he was younger - difficulties in generalisation
(-) individual differences may influence results - an issue complicating generalisation is that individuals' cycles can vary from 13 to 65 hours - Duffy observed that some have a natural preference to sleep early and wake up early (larks) and some prefer to sleep late and wake late (owls) - these individual differences cause issues for generalisation
61
What is an infradian rhythm?
- a biological rhythm that INFRequently occurs i.e occurs less than once in 24 hours
- an example is the menstrual cycle
- the menstrual cycle occurs usually over a 28-day period
62
Describe the study done by Stern and McClintock
( research into the effect of exogenous factors)
- 29 women with irregular periods
- samples were taken from 9 of them via a cotton pad under their armpits from different stages in their menstrual cycle
- these pads were then sterilised and rubbed on the other participants' upper lip
- 68% of the women experienced changes to their cycle that actually brought them closer to their "odour donor"
63
What is SAD?
- SAD stands for seasonal affective disorder
- it's a depressive disorder thought to be caused by the longer nights in the winter i.e the increased production of melatonin (pineal gland produces this in absence of light) and decreased production of serotonin
- its a type of circannual rhythm which is a type of infradian rhythm
64
infradian rhythms strengths
(+) the evolutionary advantage with having synced cycles - back in the day it would be beneficial for women to be pregnant at the same time as they can help each other
HOWEVER its argued that it should be the opposite - women being in sync makes competition for the highest quality males - so acc being out of sync will be the provide the best evolutionary advantage
(+) practical application SAD - treatment using lightboxes to stimulate serotonin rather than melatonin - in a study it relieved symptoms in about 60% of SAD sufferers - research into infradian rhythms, therefore, brings real-life benefits encouraging more research?
65
infradian rhythms weaknesses
(-) issue with validity of conclusions drawn about synchronisation from studies such as Stern and McClintock's - commentators argue that there many other factors involved in affecting the menstrual cycle such as changes in diet, stress etc - the results from Stern and McClintock's study could acc be due to chance- limiting validity
66
What are Ultradian Rhythms ?
- biological rhythms that occur MORE than once in 24 hours ( ULTRA)
- examples include The Stages Of Sleep
67
What are the stages of sleep?
- sleep occurs in 5 stages which altogther last 90 minutes and these cycles occur continously throughout the night when you are asleep
- stages 1 and 2 are light sleep where the person can be easily woken - brainwave activity slows down and becomes more rhythmic (alpha waves) and they get deeper when sleep gets deeper (theta waves)
- stages 3 and 4 involve delta waves - this is deep sleep when the person is difficult to wake
- stage 5 is REM(rapid eye movement) -body is paralysed but brain activity speeds up - there is rapid eye movement underneath the eyelids - associated with dreams
68
ultradian rhythms limitations
(-)diffs in individuals' stages of sleep thought to be due to non biological factors such as room temp
but Tucker et al conducted a study recording stages of sleep of pps in the same controlled environment for 11 days and yet still found significant individual diffs between pps - therefore diffs are biological - but presence of individual differences causes difficulties in generalisation
69
Ultradian rhythms strengths
(+) evidence for the distinct stages of sleep - Dement and Kleitman studied sleep cycles of 9 pps in a sleep lab + found evidence for distinct stages of sleep, specifically REM stage, REM has been associated with dreams - so ppls were woken during REM sleep and found that they could accurately recall their dreams - shows REM is a distinct stage -
70
What are endogenous pacemakers
- our internal body clovks that regulate many of our biological rhythms
- endogenous pacemakers are affected by the environment
- they have to be constantly reset in order for our bodies to be in synchrony with the outside world
71
Describe the role of the SCN
- the suprachiasmatic nucleus
- it is an endogenous pacemaker located in the hypothalmus
- recieves information about light even if eyes are closed and feeds this information the pineal gland
- during the night the pineal gland increases production of melatonin which induces sleepiness
- melatonin production is inhibited during times of wake
72
Describe DeCoursey et al's study
- destroyed SCN connections in 30 chipmunks who were then returned to their natural habitat and observed for 80 days
- their sleep/wake cycle disappeared and by the end a significant proportion had acc died as they were awake and vulnerable to predators when they should've been asleep
73
Describe Ralph et al's study
- took SCN cells from mutant hamsters who had an abnormal sleep/wake cycle (20 hours) and transplanted them into normal hamster
- found that the sleep/wake cycles of the normal hamsters became abnormal
- they then transplanted the SCN cells back into the mutant hamsters and the sleep/wake cycles of the normal hamsters went back to normal
74
Endogenous Pacemakers strengths
(+)the animal studies allowed for us to establish a cause and effect - as it made it more likely that the results from the study was due to the destruction of SCN(DeCoursey)
75
Endogenous pacemakers weaknesses
(-)ethical issues with animal studies esp decoursey's chimpunk study - and the findings that we've gained may not justify the actions as it's argued if we can even generalise these findings to humans
76
What are exogenous zeitgebers?
- external cues that may affect or entrain our biological rhythms, such as the influence of light on our sleep/wake cycle
- they work together with our internal cues e,g the SCN
77
Describe the role of light as an exogenous zeitgeber
- light resets the SCN thus playing a role in the sleep/wake cycle
- Campbell and Murphy investigated the effect of light
- by waking 15 pps at various times and shining a light onto a pad on the back of their knees
- this acc caused deviations in the pps' sleep/wake cycles of up to 3 hours suggesting light is a powerful zeitgeber
78
What are social cues and how do they act as exogenous zeitgebers?
79
Exogenous zeitgebers strengths
(+) practical application for SAD treatments - lightbox - found in a stidy to have relieved symptoms in up to 60% of sufferers
80
Exogenous zeitgebers weaknesses
(-) methodology flawed in Campbells and murphy's study - its yet to be replicated - also light still could've went into eye which is a major confounding variable - findings may not be valid
