topic 6 - biopsychology Flashcards
(112 cards)
1
Q
what are the 6 structures in a neuron? + draw image of neuron?
A
cell body (soma), dendrites, axon, myelin sheath, nucleus, terminal buttons
2
Q
nucleus in neurons?
A
contains DNA which codes for everything the cell needs to function
3
Q
dendrites?
A
long, receive information from neighbouring nerve cells
4
Q
cell body of neuron?
A
- also known as soma
- produces proteins needed for cell to function
5
Q
axon?
A
transmits information along its length as an electrical impulse (action potential)
6
Q
myelin sheath?
A
- protective layer around axon
- acts as insulator to speed up transmission of electrical impulses
7
Q
two parts of human nervous system?
A
peripheral and central nervous systems
8
Q
two types of peripheral nervous system + what they do?
A
autonomic = internal voluntary actions
somatic = voluntary movements and external actions
9
Q
two types of autonomic nervous system + what they do?
A
sympathetic = arousing (fight or flight mode)
parasympathetic = calming (rest and digest)
10
Q
what does the CNS consist of?
A
brain + spinal cord
11
Q
describe sensory neuron structure + functions? + draw pic
A
- detects info from your senses to pass onto CNS
- found in PNS
- cell body in centre of cell
- fewer dendrites as don’t receive info from other neuron’s
12
Q
structure, function + diagram of relay neuron?
A
- only found in CNS and visual system
- allows sensory and motor neuron’s to communicate with each other
- analyse the info to make decisions
- shorter axon as only sending messages short distances
13
Q
structure, function + diagram of a motor neuron?
A
- allow muscle contractions
- cell body found in CNS but axons found in PNS
- very long axon (up to 1 metre)
14
Q
what is resting potential?
A
when the inside of a neuron is negatively charged relative to the outside
15
Q
what is action potential?
A
when a neuron is activated by a stimulus causing the inside to become positively charged for a short time
16
Q
what is an excitatory neurotransmitter?
A
- post synaptic neuron is more likely to fire
- as it causes positive electrical charge in cell membrane
- resulting in EPSP (excitatory post synaptic potential)
17
Q
what is an inhibitory neurotransmitter?
A
- post synaptic neuron less likely to fire
- as has caused IPSP (inhibitory post synaptic potential)
18
Q
why can information only travel in one direction at a synapse?
A
- receptors are only found on post synaptic neurones
- must diffuse from high to low concentration
- vesicles only found in pre synaptic neurones
19
Q
what are the 8 steps of synaptic transmission?
A
- an electrical impulse travels along the axon of the pre-synaptic nerve cell
- when the signal reaches the terminal buttons, it stimulates the vesicles to fuse with the cell membrane
- the neurotransmitters are released into the synapse where they diffuse across the synaptic gap
- the neurotransmitters bind to the receptor sites on the post synaptic neuron
- some neurotransmitters are excitatory - making the nerve cell more positively charged
- some neurotransmitters are inhibitory - making the nerve cell more negatively charged
- summation is the summing up of all neurotransmitters whether excitatory or inhibitory determining the action potential of the nerve cell
- if summation is positive, cell is likely to fire the electrical signal and vice versa
20
Q
example of summation?
A
eg: 1 excitatory, 2 inhibitory, = -1 negative so unlikely to fire
21
Q
what is the function of the endocrine system?
A
to regulate the activity of cells and organs within the body
22
Q
what do glands do?
A
secrete hormones (chemical messengers) which travel to target cells via the bloodstream
23
Q
what do hormones do?
A
bind to receptors on their target cells, a message is then transmitted causing the target cell to respond and take specific action
24
Q
describe the hormone oxytocin?
A
- secreted from pituitary gland
- targets cells in the uterus
- causes uterus to contract during childbirth
25
describe the hormone thyroxine?
- secreted from thyroid gland
- targets all body cells
- plays role in digestive function, metabolism, heart function, bone health
26
describe the hormone adrenaline?
- secreted from adrenal gland
- targets heart cells, lung cells, mouth cells + more
- causes changes in body that help you act in sudden stressful situation (fight or flight)
27
compare the nervous system and endocrine system?
nervous = faster, quicker effects, messengers are neurotransmitters and travel via electrical impulses, have target cells, allow communication through body
endocrine = slower, longer lasting effects, messengers are hormones and travel through bloodstream, have target cells, allow communication throughout body
28
stages of fight or flight response?
- stressor is recognised
- hypothalamus in brain activates sympathetic branch of autonomic nervous system
- this triggers release of adrenaline from adrenal medulla in centre of adrenal gland, just above kidneys
- "adrenaline rush" occurs, increasing heart rate, breathing rate, respiration, and pupil size, and decreasing salivation causing dry mouth, inhibits digestion and the bladder, and releases more glucose from liver
- this all leads to readiness for fight or flight
29
which hemisphere controls which sides of body?
left hemisphere controls right hand side of body and vice versa
30
what is the corpus callosum?
bundle of nerve fibres that connects the two hemispheres and allows them to connect to each other
31
what is the outer layer of the brain?
cerebral cortex (3mm thick)
32
what are structures other than cortex of brain known as?
sub-cortical structures
33
what is localisation of function?
the theory that different areas of the brain are responsible for different behaviours, processes or activities
34
what is equipotentiality/the holistic machine idea?
- opposite to localisation of function
- idea that your whole brain works together to perform each function
35
what is Broca's area?
- area of the frontal lobe in left hemisphere
- responsible for speech production
- when damaged, Broca's aphasia occurs
36
what is Wernicke's area?
area of temporal lobe (encircling auditory cortex), in left hemisphere, responsible for language comprehension
37
diagram of areas, lobes and cortex's in brain?
google or diagram in folder
38
what is the motor cortex?
region of the frontal lobe involved in regulating movement
39
what is the somatosensory cortex?
area of the parietal lobe that processes sensory information such as touch, temperature, texture.
40
what is the visual cortex?
part of the occipital lobe that receives and processes visual information
41
what is the auditory cortex?
located in temporal lobe and concerned with the analysis of speech based information, damage could lead to hearing loss
42
case study of HM?
- HM suffered from epilepsy
- he had both sides of his hippocampus removed
- he had no memories + lost the ability to form new memories
- his intellectual abilities remained + he had normal digit span
- could learn new motor skills by repeated practice
43
evaluation of HM case study?
- this is strong evidence that the hippocampus is responsible for memory
- has only happened to one male and he had epilepsy so not generalisable to others
- removing the hippocampi may have damaged surrounding tissues decreasing accuracy
44
Brocas study of Leborgne and others?
- Leborgne appeared perfectly healthy but couldn't speak apart from one syllable 'tan'
- when he died, Broca inspected his brain and found a lesion in frontal lobe of left hemisphere (Broca's area)
- he found the exact same lesion in a different patient who could only say 5 words
45
evaluation of Broca's study of Leborgne and others?
- multiple cases with consistent results so conclusive and replicable
- however in some of the cases, other brain areas were also damaged
46
what is hemispheric lateralisation?
- the idea that the brain hemispheres are functionally different
- certain mental processes and behaviours are mainly controlled by one hemisphere rather than the other
47
what does contralateral mean?
left hemisphere controls right side of body and vice versa
48
describe the Sperry (1968) study on split brain patients?
- participants gaze on fixation point on a tachistocope
- a stimulus is projected onto the screen
- stimulus for only 0.1 second to ensure it only goes to one hemisphere
49
what do the left/right hemispheres mainly control?
left = language and speech
right = motor and face identification
50
response of split brain patients to seeing word key ring with key on LHS and ring on RHS of screen?
- would say they saw the word 'ring' as left hemisphere controls speech
- when asked to pick up item, left hand would pick up key as it was seen by left visual field and processed by right hemisphere which controls left hand
51
split brain patient response to seeing chimeric face?
- would say that they saw a man as left hemisphere controls speech
- if asked to select image they would pick up image of woman
52
describe contralateral vision?
right visual field goes to left hemisphere and vice versa
53
strengths of split-brain research?
- tests performed in highly controlled lab
- controlled stimulus only presented for 0.1 second to ensure info only went to one hemisphere
- results compared to control group to show difference
- wealth of data collected as multiple tests were performed on every split brain patient
- research based on multiple patients who all demonstrated same results
54
weaknesses of split-brain research?
- only 11 males studied, female brains are less lateralised and work differently so results don't generalise
- confounding variable that all patients had been previously medicated for epilepsy which could have altered brain
- we can't be certain that full brain disconnection occurred following surgery
- language isn't permanently lateralised to left hemisphere, right hemisphere can do it if necessary
55
case study of JB (split brain patient)?
7 years after his surgery, he was able to name out loud 25% of stimuli presented to his left visual field
56
what is functional recovery?
the brain can recover some of its lost functions following a brain trauma or disease, due to brains plasticity
57
what are two main types of functional recovery?
neural regeneration and neural reorganisation
58
describe neural regeneration?
axon sprouting occurs which is where new nerve endings grow and connect with undamaged areas which compensate for damaged areas
59
describe neural reorganisation?
the functions controlled by the damaged brain areas can be transferred to the homologous areas on the opposite side of the brain as well as other undamaged areas
60
describe EB (2003) case study?
- EB had his entire left hemisphere removed when he was 2.5 years old to remove a large tumour
- he lost emerging language abilities but 2 years later there were no language problems and his language appeared normal in everyday life
- at age 17 he was tested again and he was found to be slower than average at naming objects in pictures
61
what factors affect functional recovery?
education, age, gender, physiotherapy quality/intensity, financial situation, extent of damage
62
how does education level affect functional recovery (including case study)?
- Schneider et al (2014)
- he found that 39% of university students that had suffered brain damage achieved disability free recovery (DFR)
- compared to only 10% of those who left school early
- encourages young people to remain in education - practical application
63
how does age affect functional recovery (including case study)?
- Marquez de la Plata et al (2008)
- found that following brain trauma, older patients (40+ years old) regained less function in treatment than younger patients
- would encourage doctors to be selective and younger patients may be prioritised
- weakness that is not specific ages but a large age range
64
how does gender affect functional recovery (including case study)?
- Ratcliffe et al (2007) studied 325 patients who were admitted to a care facility 24 hours after traumatic brain injury where they received rehab
- 1 year later they completed various assessments of cognitive functioning and females outperformed males
- females have less lateralisation so will already have both hemispheres doing at least part of the same function
65
what is plasticity?
the brains ability to change and adapt, structurally and functionally, because of experience, known as neuroplasticity. all everyday activities can lead to plasticity
66
can the brain only change in childhood?
new evidence suggested the brain can create new neural pathways and alter existing ones in response to experience and learning at any point in life
67
what are the two main processes of plasticity?
synaptic pruning and synaptogenesis
68
what is synaptic pruning?
unused/weaker neuronal connections are eliminated whilst frequently used/stronger connections are retained
69
what is synaptogenesis?
new neuronal connections are created due to new stimuli/experience
70
describe Boyke et al (2008) case study for plasticity?
- 60 year olds were taught to juggle
- their brains were scanned before and after
- there was an increase in grey matter in the visual cortex (synaptogenesis)
- when they stopped practicing the changes reversed (synaptic pruning)
71
describe the SAFIA case study into plasticity?
- at Swedish Armed Forces Interpreter Academy, young recruits learn new language at very fast pace
- control group of medicine and cognitive science students used to compare to group of young recruits
- both groups given MRI study before and after 3 month period of intensive study
- brain structure of control group remained unchanged but in the language students, the hippocampus and three parts of the cerebral cortex grew
72
what are implications of plasticity research evidence for nature nurture debate?
- everyone is born with nerve cells (nature)
- nurture has biggest influence as your personal experiences through life create the trillions of connections between your nerve cells
73
are the brain changes that take place permanent?
- no, if a skill is learnt then synaptogenesis occurs but if its not practiced then synaptic pruning occurs, reversing the changes
74
what are the practical applications of plasticity research?
- gives optimistic outlook to everybody with the hope that they can always alter their brain with hard work
- can help with treatment and physiotherapy for individuals who have suffered strokes, brain damage or even paralysis
75
what is spatial resolution?
smallest feature or measurement that a scanner can detect, higher spatial resolution allows psychologists to discriminate between different brain regions with greater accuracy
76
what is temporal resolution?
- the accuracy of the scanner in relation to time, so how quickly the scanner can detect changes in brain activity
- high temporal resolution allows psychologists to predict with a high degree of accuracy the onset of brain activity
77
how does post-mortem work?
- establishes physical anatomical structure of brain following death
- often conducted on individuals who showed particular behaviour whilst alive that suggested brain damage
- researcher can examine brain for abnormalities that might compare to a 'normal' brain
78
strengths of post-mortem as a brain studying technique?
- can help to confirm a diagnosis
- allows research without inflicting pain
- able to see deeper structures in the brain
79
weaknesses of post-mortem as brain studying technique?
- not possible to compare measurements of post-mortem to living brain
- not possible to study brain function
- not many people would consent to donating their brain
80
what is fMRI?
- functional magnetic resonance imaging
- images parts of the brain that become active during different mental processes
- measures blood flow in brain using radio waves and a magnetic field
81
strengths of fMRI?
- non invasive and doesn't involve radiation
- excellent spatial resolution
- easy for experimenter to use
82
weaknesses of fMRI?
- expensive compared to other techniques
- poor temporal resolution
- may not represent moment to moment brain activity accurately
83
what is EEG?
- an electroencephalogram
- involves placing electrodes on scalp to detect electrical signals produced when the neurons send messages to each other as a measure of general brain activity
84
strengths of EEG?
- good temporal resolution
- digitalised so easier to interpret
- silent so produces better and more accurate results
85
weaknesses of EEG?
- poor spatial resolution
- doesn't specify where in brain the activity is coming from
- doesn't show a very clear link between structure and function
86
what is an ERP?
- event related potential
electrodes are attached to scalp and stimulus is presented
- researcher looks for activity that is specifically related to that stimulus
87
strengths of ERP?
- more specific than raw EEG readings
- excellent temporal resolution
- non invasive and safe as doesn't involve radiation
88
weaknesses of ERP?
- differing procedures have been adopted so they aren't standardised and are hard to compare and replicate findings
- to be successful all extraneous inference needs to be eliminated which is hard to achieve
- low spatial resolution
89
what is a biological rhythm?
a pattern of behaviour or a process which repeats itself on a regular basis over a specific period of time
90
circadian rhythm?
- lasts 24 hours
- eg: sleep-wake
91
infradian rhythm?
- lasts longer than 24 hours
- eg: hibernation, seasonal depression
92
ultradian rhythm?
- lasts less than 24 hours
- eg: blinking, sleep, heartbeat
93
describe Siffree (1962) case study on biological rhythms?
- he spent 2 months in dark cave with no clocks or natural light, then 7 months
- maintained regular sleep-wake cycle but it extended to 25 hours which proves we have internal 25 hour body clock but external influences keep it 24 hours
- one unique male so not generalisable
94
what is an endogenous pacemaker?
an internal factor that controls your biological rhythms such as genes, hormones, brain structures, neurotransmitters
95
what is an exogenous zeitgebers?
an external factor that controls our biological rhythms such as sunlight levels, lifestyle, social cues, work
96
7 steps of sleep-wake cycle?
1. the SCN (suprachiasmatic nucleus) is a small cluster of about 10,000 neurons located in hypothalamus
2. SCN is just above the optic chiasm, which is where the optic nerves (receiving info from both eyes) crosses over
3. the SCN is connected to the retina of each eye by neural pathways, allowing it to receive info about how much light is falling on the retina, even when our eyes are shut
4. if the SCN is removed or damaged then the sleep-wake cycle is disrupted as light is no longer able to reset the clock of each day
5. another neural pathway links the SCN to the pineal gland
6. the pineal gland contains light sensitive cells and when light is sensed, production of melatonin is inhibited, and vice versa
7. if circulating blood levels of melatonin rise, we feel the need to sleep, but if levels fall, we feel alert
97
describe the Ralph (1990) study about the sleep-wake cycle?
- discovered mutant hamster with abnormal circadian rhythm of 20 hours instead of 24 hours
- their SCN's were transplanted into hamsters with normal 24 hours rhythm
- the normal hamsters then displayed the mutant 20 hour rhythm
- the transplantation of other parts of the brain had no effect
- hamsters may not generalise to humans fully although we do both have SCN's
- unethical
- well controlled so valid conclusion
98
describe the Aschoff + Wever (1976) study about the sleep-wake cycle?
- 50 participants spent 4 weeks alone in underground soundproof bunker with no watch or natural light
- all but one displayed circadian rhythm of between 24 - 25 hours with anomaly being 29 hours
- replicable and reliable results
- is still relatively small sample size of people who chose to do this
99
describe Campbell + Murphy (1998) study about sleep-wake cycle?
- woke 15 participants at various times throughout the night and shone a light on the back of their knees
- was found that a deviation in their sleep-wake cycle of up to 3 hours occurred as a result
- suggests we have light detecting receptors in other parts of our body
- person might have just seen the light
- study lacked control
- when it was replicated they did not get the same results
100
human menstrual cycle as an infradian rhythm?
- 28 days long
- controlled by endogenous pacemakers, but there are on exogenous zeitgebers involved such as birth control and synchronization
101
10 stages of the menstrual cycle?
1. hypothalamus sends signal to pituitary gland
2. pituitary gland releases FSH into blood
3. FSH targets ovaries causing healthy egg cell to mature + stimulates ovaries to release oestrogen
4. when oestrogen rises, release of FSH is inhibited, meaning only one egg cell will mature each cycle
5. oestrogen stimulates pituitary gland to release LH
6. LH peaks on day 14, causing egg cell to be released into fallopian tube
7. progesterone released causing uterus lining to thicken ready for fertilised egg to be implanted
8. if pregnancy occurs, placenta continues to produce progesterone
9. if no pregnancy, oestrogen and progesterone levels fall
10. uterus lining breaks away (menstruation)
102
describe SAD (seasonal affective disorder)?
- type of depression that occur during winter months
- symptoms of low mood, poor concentration, similar to those of depression
- a light box with intensity of 10,000 lux is proposed as prevention /cure to SAD
- the exogenous zeitgeber of light interacts with pineal gland inhibiting melatonin production
- could be caused not just by darkness, but by weather, lack of exercise and socialising etc
103
sleep cycle?
- one sleep cycle is 90 minutes long
- includes REM (rapid eye movement) and NREM (non rapid eye movement) sleep
- stages 1 to 4 are NREM sleep and stage 5 is REM
104
plot stages in for 5 sleep cycles?
1st - 1,2,3,4,3,2,REM
2nd - 2,3,4,3,2,REM
3rd - 2,3,2,REM
4th - 2, REM
5th - 2, REM,awake
105
106
what are the 4 brain lobes?
temporal, frontal, parietal, occipital
107
function of frontal lobe?
- problem solving
- emotional traits
- speaking
- voluntary motor activity
108
function of temporal lobe?
- understanding language
- behaviour
- memory
- hearing
109
function of parietal lobe?
- knowing right from left
- sensation
- reading
- body orientation
110
function of occipital lobe?
- vision
- colour perception
111
function of cerebellum?
- balance
- coordination
- fine muscle control
112
function of brain stem?
- breathing
- body temperature
- digestion
- swallowing
