biopsychology Flashcards
(84 cards)
1
Q
what is the nervous system
A
specialised network of cells in the human body and is our primary internal communication system, it is based on eletrical and chemical signals
2
Q
what are 2 main functions of nervous system
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to collect, process and respond to infomation in the environment, to co-ordinate working of different organs and cells in the body
3
Q
what are the 2 sub systems of the nervous system
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central nervous system, peripheral nervous system
4
Q
what is the CNS made up of
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brain and spinal cord
5
Q
what is the brain
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centre of all consious awareness, brains outer layer, cerebral cortex, is very thin, brain is highly developed in humans and distinguishes our mental function from other animals, brain divided into 2 hemishperes
6
Q
what is the spinal cord
A
extension of the brain, passes messages to and from the brain and connects nerves to PNS, also responsible for reflex actions like pulling hand away from hot plate
7
Q
what is the PNS
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transmits messages via millions of neurones, to and from CNS
8
Q
what are subdivisions of preipheral nervous system
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somatic nervous system and autonomic nervous system
9
Q
what is somatic nervous system
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governs muscle movement and recieves info from sensory receptors
10
Q
what is autonomic nervous system
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governs vital functions in the body like breathing, heart rate, digestion and stress response
11
Q
what does automonic nervous system divide into
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sympathetic NS (enters body into fight or flight by release of adrenaline), parasympathetic NS (body is in a relaxed state)
12
Q
what is the endocrine system
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works alongside nervous system to control vital funtions in body, it acts more slowly than NS but hs widespread and powerful effects
13
Q
how does the endocrine system work
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via release of hormones, glands like thyroid gland produce these hormones and effect parts of the body where a cell has a receptor complementary to the hormone
14
Q
what are the effects of thyroxine produced by thyroid gland
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effects heart cells increasing HR, also affects cells throughout body by increasing metabolic rate affecting growth rates
15
Q
do hormones only effect 1 cell type
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no usually they effect multiple cells
16
Q
what is the main endocrine gland
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the pituitary gland
17
Q
what is the pituitary gland
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located in the brain, often called the master gland because it controls the release of horomones from all the other endocrine glands in the body
18
Q
what is an example of the endocrine system and autonomic nervous system working together
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fight or flight response
19
Q
what is the fight or flight response
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when are stressor is percieved, the hypothalamus triggers the pituitary gland and triggers the sympathetic NS of the autonomic NS. ANS changes from parasympathetic (resting) state to physiologically aroused sympathetic state
20
Q
what is adrenaline
A
a stress hormone released from adrenal medulla into the bloodstream, it triggers physiological changes in the body (increased heart rate) which creates physiological arousal necessary from fight or flight response
21
Q
what kind of action does adrenaline trigger
A
an acute response, the release of adrenaline instantly causes these physiological changes, an automatic response of the body, this explains why stress, panic or excitment are felt very quickly after the stressor
22
Q
what is the parasymapthetic action once a threat has passed
A
parasympathetic nervous system returns body to resting state, it is opposite to sympathetic NS (they are antagonistic), refered to as rest and digest response as it reduces the body’s activity that were increased by symathetic NS
23
Q
wjat did Broca and Wernicke discover in 19th centurary
A
areas of the brain are associated with certain physical and physiological functions, before this scientists supported holistic theory of the brain (all parts were involved in processing thought and action
24
Q
What was localisation function by Broca and Wernicke
A
different parts of the brain perform different tasks snd are involved with different parts of the body, it follow then, that if a certain area of brain is damaged through illness or injury functions associated with that area will be damaged
25
what is the main part of the brain
cerebrum, divided into 2 hemispheres (right and left)
26
what is lateralisation
some of our physical and psychological functions are controlled or dominanted by a particular hemisphere
27
what is the general rule of lateralisation
activity on left side of the body, controlled by right hemisphere, activity on right side of the body, controlled by left hemisphere
28
what is the outer layer of both hemispheres and how does it divide up
cerebral cortex, subdivided into 4 centres (lobes of the brain), frontal lobe, parietal lobe, occipital lobe and temporal lobe
29
what is a lobe
a part of an organ that isseparate in some way from the rest, each brain llobe is associated with a different funtion
30
what is at the back of the frontal lobe in both hemispheres, what does it control adn what happens when its dammaged
the motor area, controls volontary movement in opposite sides of the body, damage may result in loss of control over fine movements
31
What is found at the front of both parietal lobes and their function
somatosensory area, separated from motor area by a vally called the central sulcus, it is where sensory info from skin is represented, the more sensitive an area on our skin the more somatosensory area will be devoted to that
32
what is at the back of the brain in occipital lobe and what does it control
visual area, eye sends infomation to these areas, so damage to left hemisphere of this area will cause blindess in the right field of both eyes
33
what is found in the temporal lobes and what does it control
auditiory area, analyses speech-based info, damage may produce hearing loss, more damage more hearing loss and damage to Wernickie area in temporal lobe may affect ability to understand language
34
what side of the brain controls language and what 2 areas were identifird
left sode, Broca identified small area in left frontal lobe responsible for speech production, damage to Broca's area causes speech which is slow, laboured and not fluent. Wernicke identified people who had no problem speaking but problems understanding language, this region called Wernicke area in left temporal lobe responsible for language understanding, people with damage to this area produce nonsense words as part of their content of their speech
35
what is a strength of localisation fo function in the brain
damaged areas in the brain have been linked to mental disorders. Neurosurgery is last resort to treat some mental disorders, targeting specific areas of brain involved. E.g. cingulotomy involves isolating region called cingulate gyrus which is linked to OCD. Dougherty et al reported on 44 ppeople with OCD who had a cingulotomy. After 32 weeks 30% met criteria for successful response to surgery and 14% had partial response. This suggests behavours associated with serious mental disorders may be localised
36
what is another strength of localisation fo function in the brain
evidence from brain scans supports idea that brain functions are localised. Peterson et al used brain scans to show how Wernicke's area was active during listening tasks and Broc's area active during reading tasks. Also, another study shows semantic and episodic memories are in diffferent parts of prefrontal cortex. Thse conform localised areas for different behaviours. So, objective methods for measuring brain activity have provided scientific evidence that brain functions are localised
37
what is a counterpoint of localisation fo function in the brain
Lashley removed areas of cortex (10-50%) in rats that were learning the route of a maze. No area proven to be more important than other areas in terms of rates ability to learn the route. Process of learnign required every part of cortex than 1 particular area. Suggests high cognitive processes like learning aren't localised but distributed in a more holistic way.
38
what is a limitation of localisation fo function in the brain
language may not be localised to just Broca and Wernicke area's. Dick et al review revelaed that only 2% modern researchers think language is completely controlled by Broca and Wernicke area. fMRI mean neural processes in brain can be studied with more clarity than before and found language is distributed far more holistically than previously thought. Language streams have been identified across the cortex. Suggests language may be organsied more hoilisitcxally which contradicts localisation theory.
39
what dies it mean that the brain is lateralised
split into 2 hemispheres
40
where is language controlled in the brain
for most people in just the left hemisphere, Broca's area in left frontal lobe and Wernicke's area in left temporal lobe, so we can say language is lateralised (only performed in 1 hemisphere) although right hemisphere contributes to the emotion put into the words (LH is the analyser and RH is synthesiser)
41
what are functions which are not lateralised
vision, motor and somatosensory areas
42
what is special about motor area and lateralisation
contralateral wiring, RH conrtols left side and LH controls right side movement
43
how does vision work with lateralisation
it is both contralateral and ipsilateral (opposite and same side), each eye recieves light from left visual field (LVF) and right visual fireld (RVF), LVF for both eyes is connected to RH but RVF for both eyes is connected to LH, thhis enables visual areas to compare different perspectives from each eye and aid depth perception, this is similar for sounds input into auditory area to help us accurately locate source of sound
44
what does a split brain operation involve
severing connections between RH and LH, mainly corpus callosum, it is a surgical procedure to reduce epilepsy, during epiletic seizure brain experiences excessive electrical activity which travelks from one hemisphere to the other, To reudce fits connections are cut spitting the brain into 2 halves
45
what dies split brain research study
how the hemispheres function when they can't communicate with each other
46
What was Sperry research
devised a system to study how 2 separated hemispheres deal with speech and vision
47
what is Sperry procedure
11 people who had split brain operation were studied using a special set up in which image was projected to participants RVF (LH) and same or different image projected to LVF (RH). In normal brain corpus callosum immediately shares info between both hemispheres giving complete picture of visual world, but in split-brain participant this can't happen
48
what were Sperry findings
when picture shown to RVF particiant could describe what was seen but not when shown in LVF, said nothing was there. This is as in connected brain messages from RH relayed to language centres in LH, but not possiblke with split-brain, Participant vouldn't use verbal labels when image in LVF they could select a matching object out of sight with left hand (RH), left hand could selct object most closely most closely related to image (ashtray and cigarette), In pictiure shown in LVF there was emotional reaction (laugh) but participants usually reported seeing nothing
49
what were sperry conclusions
observations show how certain functions are lateralised in brain and support view that LH is verbal and RH is silent but emotional
50
What is a strength of hemispheric lateralisation
Research showimg even in connected brains, 2 hemispheres process info differently. E.g. Fink et al used PET scand to identify which areas of brain were active during visual processing task. When participants w connected brains were asked to attend to whole image, regions of RH more active, when required to focus on finer details LH more active. This suggests that, for visual processing, hemispheric lateralisation is feature of connected and split brains
51
What is a limitation of hemispheric lateralisation
Idea that LH as analyser and RH as synthesiser may be wrong. May be different functions in RH and LH but research suggests people dokt have dominant side of their brain which creates a different personality. Nielsen et al analysed brain scans from 1000 ppl 7-29yo and found people use certain hemispheres for certaon tasks, but no evidence of dominant side. Suggest notion of right or left brained ppl is wrong
52
What is strength of split brain research
Support from more receant studies. Gazzaniga showed split brain participants peform better than connected on some tasks. E.g. faster at identifying odd one out in an array of similar objects than normal controls. In normal brain, LH better congnitive strageies watered down by inferior RH. Supports Sperry ealy fondings on left brain, right brain distinctikn.
53
What is limitation of split brain research
Sperry research is only a causal relationship. Behaviour in Serry experiment compared to neurotypical control group. Issue is no participants in control has epilepsy, major confounding variable. Any differences observed could be due to the epilepsy not the split brain. This means sole unique features of split brain participants cognitive abilities may be due to their epilepsy
54
how does the brain appear 'plastic'
it can change throughout life
55
how does brain change throughout life
in infancy, brain experiences rapid growth in nummber of synpatic connections it has, as we age rarly-used connections are deleted and frequently-used connections are strengthened (known as synpatic pruning)
56
what does synaptic pruning allow
lifelong plasticity where new neural connections are formed in repsonse to demands of the brain
57
What did Maguire et al study and find
brains of london taxi drivers and found signficantly more grey matter in posterior hippocampus than in a matched control group, this part of brain associated with development of spatial and navigational skills, for their training london taxi drivers must take a complex test assessing their recall of city streets and possible routes and this learnign experience altered the taxi drivers brains. Also, more time taxi driver in the job, more pronounced structural difference (positive correlation)
58
what did Draganski find when researching plasticity
imaged brains of med strudents 3 months before and 3 months after final exams, learning-induced changes were seen to have occured in posterior hippocampus and parietal cortex as a result of learning
59
how does brain adapted after physical trauma or other trauma like strokes
unaffected areas of the brain able to adapt and compensate for damaged areas
60
what is the functional recovery that happens in the brain an example of
neural plasticity
61
what is neural plasticity
healthy brain areas may take other functions of those areas that are damaged, destroyed or even missing
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what do neuroscientists say about neural plasticity
it can occur qucikly after trauma (spontaneous recovery) and slow down after several weeks or months, at which point patient may need rehabilitative therapy to further their recovery
63
what happens during brain recovery
brain able to rewire and reorganise itself by foming new synpatic connections close to area of damage, secondary neural pathways that would not typically be used to carry out certain functions are activated to enable functioning to continue often same way as before
64
what 3 things suport the theory of how brain recovers from trauma
axonal sprouting, denervation supersensitivity, recruitment of homologous (simiklar areas)
65
what is axonal sprouting
growht of new nerve endings which cinnect with other undamaged nerve cells to form new neural pathways
66
what is denervation supersensitivity
occurs when axons that do a similar job become aroused to higher level to compensate for lost ones, but, can have negative effect of oversensitivity to messages like pain
67
what is recruitment of homologous (similar) areas on the opposite side fo the brain
specific tasks can still be performed, like if brocas area was damaged on left side of brain, right side equivalent would carry out its functions, after period of time functionality may shift back to left side
68
whats a limitation of plasticity
may have negative behavioural consequences. Evidence has shown brain's adaptation to prolonged drug use leads to poorer cognitive function in later life, and incresaed dementia risk. Also, amputees often develop phantom limb causing unpleasant sensations. This suggests brains ability to adapt to damage is not always beneficial.
69
whats a strength of plasticity
brain plasticity may be life long ability. Plasticity rexuces with agebut Bezzola showed how 40h of golf trainign produced changes in the neural representation of movements in participants age 40-60. Using fMRI, researcher observed increased motor cortex activity in onvice golfers compared to control group, suggesting more efficient neural representation after training. Shows neural plasticity can continue through lifespan
70
what is strength of functional recovery
real world application. Understanding process of plasticity contributed to neurorehabilitation. Understanding axonal growth allows new therapies to be tried like constraint induced movement therapy used in stroke patients (use affected part of body whilst unaffected part is restained). Shows that research into functional recovery useful in helping medical professionals know when interventions need to be made.
71
what is limitation of functional recovery
level of education may influence recovery rates. Schneider et al found more time people with brain injury spent in education the greater their chance of disability-free recovery (DFR). 40% of participants who achieved DFR spent over 16years in education compared to 10% who spent less than 12 years in education. This implies that people with brain damage who have insufficient time in education are less likely to achieve a full recovery.
72
what is the purpose of scanning the brain
medical purpose to asses injury or in psychology to investigate localisation
73
how does function magentic resonance imaging (fMRI) work
by detecting changes in both blood oxygenation and flow that occur as a result of neural activity in specific parts of the brain, when brain area more active consumes more oxygen and to meet this demand blood flow directed to active areas (haemodynamic response). fMRI produces 3D images (activation maps) showing which parts of brain are involved in a particular mental process and this has important implications for our understanding of localisation of function
74
what are electroencephalograms (EEG)
measures electrical activity within brain via electrodes fixed to an individuals scalp using skull cap. Scan recording represents brainwave patterns that are generated from action of thousands of neurones, providing an overall account of brain activity. EEG often used as diagnostic tool for unsual arrhythmic patterns of activity to indicate neurological abnormalities like epilepsy or tumours
75
what are event-related potentials (ERP)
EEG has many scinetific and clincial applications, but it is overly general measure of brain activity. EEG data has all neural responses associated with specific sensory, cognitive and motor events that may be of interest to cognitve neuroscientists. Using statistical averging technique, extraneous brain acitvity from original EEG recording it filtered out expect the elementes relating to the subject in question. What is left is the ERP(types of brainwaves triggered by certain events).
76
what are post-mortem examinations
technique involving analysis if persons brain after death. In osychological research, people with rare disorder or have unsual deficits in cogntive processes or behaviour during their life time may have a post-mortem. Areas of damage examed after death to establish likely cause of the defects. May also invlve comparison with neurotypical brain .
77
what is a strength of fMRI
It does not rely on use of radiation. If adminsitered correctly it is risk free, non-invasive and straight forwards to use. It also provides images with high spatial resolution, depicting detail by the militmeter and providing a clear picture of how brain activity is localised. This means that fMRI can safetly provide clear picture of brain activity.
78
what is a limitation of fMRI
fMRI is expensive compared to other neuroimaging techniques. It has poor temporal resolution as there is around 5 second time lag behind image on screen and initial firing of neural acitivyt. This means fMRI may not truely represent moment-to-moment brain activity.
79
what is a strength of EEG
useful in studying stages of sleep and diagnosis of conditions like epilepsy (characterised by random bursts of brain activity easily detected on EEG). It also have extremly high temporal resolution (single millisecond). This shows real world usefulness of the technique.
80
what is a limitation of EEG
EEG lies in generalised nature of infomation received from thousands of neurones. EEG signal is also not useful for pinpointing exact source of neural activity. Therefore, it does not allow researchers to distinguish between activities orientating in different but adjacent locations.
81
what is a strength of ERP
ERP allow much more soecific measurement of neural processes than could ever be achieved using raw EEG data. As ERPs derive from EEG measurements, thery have high temporal resolution compared to fMRI. This means ERPs are frequently used to measure cogntive functions and deficits like allocations of attentional resources and maintenance of working memory.
82
what is a limitation of ERP
lack of standardisation in ERP methology between different research studies which make it difficult to confirm findings. Further issue is in order to establish pure data in ERP studies, background noise and extrabeous material must be comppletly eliminated. This is a problem as it may not always be easy to achieve.
83
what is a strength of post-mortems
Infomation from them was vital in early understanding of brain processes. Broca and Wernicke both relied on post-mortems to establish links between language, brain and behaviour years before neuroimaging was avaliable. HM brains was also studied post-moretem to establsih areas asociated with memory deficits. This means post-mortems provide useful infomation.
84
what is a limitation of post-mortems
Causation is issue with these. Observed damage to brain may not be linked to deficits but some other unrelated trauma. Furthermore, post-mortem studies raise ethical issues of consent from the individual before death. Participants may not be able to provide informed consent, e.g. HM who lost ability to form memories so couldn't provide consent (but post-mortem still carried out). This challenges usefulness of post-mortem research in psychological research
