4.2.2 BIOPSYCHOLOGY Flashcards
define the nervous system
a specialised network of cells
the primary internal communication system
based on electrical and chemical signals
what are the two main functions of the nervous system
• to collect, process and respond to information in the environment
• to coordinate the working of different organs and cells in the body
what are the two main components of the nervous system
central nervous system
peripheral nervous system
what are the two main components of the peripheral nervous system
autonomic nervous system
somatic nervous system
what are the two components of the autonomic nervous system
sympathetic nervous system
parasympathetic nervous system
what is the central nervous system made up of and what are the functions
• the brain
centre of all conscious awareness
divided into two hemispheres
• the spinal cord
passes messages to and from the brain
responsible for reflex actions
what is the function of the peripheral nervous system
transmits messages via millions of neurons to and from the cns
what are the functions of the autonomic nervous system
• vital functions in the body such as breathing, heart rate, digestion, sexual arousal and stress
• divided into sympathetic and parasympathetic
what are the functions of the sympathetic nervous system
• muscle movement and receives information from sensory receptors
• controls voluntary movements
describe the endocrine system
• networks of glands around the body
• works alongside the nervous system to control vital functions in the body
• acts more slowly than the nervous system but has widespread, powerful effects
• glands release hormones into the bloodstream
• affect any cell with a receptor for that hormone
outline the flight or fight response from start to finish
stressor is perceived, hypothalamus activates pituitary gland, ans changes to sympathetic state, adrenaline released from the adrenal medulla, fight or flight
what are the biological changes associated with the sympathetic nervous system
slows digestion, inhibits saliva, increases heart rate, stimulates glucose production, stimulates urination, dilates pupils, dilates bronchi
what are the biological changes associated with the parasympathetic nervous system
increases digestion, increases saliva production, decreases heart rate, stimulates bile, inhibits urination, constricts pupils, constricts bronchi
what is a neuron
basic building blocks of the nervous system and are nervous cells that process and transmit messages
what are the different types of neuron
sensory, relay, motor
what is the function of a sensory neuron
carries messages from peripheral nervous system to the central nervous system
what is the function of a relay neuron
connects sensory neurons to the motor or other relay neurons
what is the function of a motor neuron
connects the central nervous system to the effectors
name the parts of a neuron
dendrites, nucleus, cell body, axon, schwanns cells, myelin sheath, node of ranvier, axon terminals
describe the process of electrical transmission
when a neuron is in resting state the inside of the cell is negatively charged, when a neuron is activated by a stimulus the inside becomes positively charged for a split second which creates an electrical impulse that travels down the axon
describe the process of synaptic transmission
neurons communicate with eachother within groups known as neural networks, neurons are separated by synapses, signals between neurons are transmitted electrically but are transmitted chemically across the synapse
what is a neurotransmitter
brain chemicals that diffuse across a synapse to the next neuron
direction of travel is one way
has a specific molecular structure
have specific functions
define excitation
caused by adrenaline
postsynaptic neuron becomes positively charged and is more likely to fire
define inhibition
caused by serotonin
postsynaptic neuron becomes negatively charged
less likely to fire
what is summation
determines the firing of a neuron
excitatory and inhibitory influences are summed: if the net effect on the postsynaptic neuron is inhibitory then the postsynaptic neuron is less likely to fire. if net effect is excitatory it is more likely to fire once the electrical impulse is created it travels down the neuron. therefore, the action potential of the postsynaptic neuron is only triggered if the sum of the excitatory and inhibitory signals at any one time reaches the threshold.
define localisation of function
different parts of the brain perform different tasks
define lateralisation
some of our physical and physiological functions are controlled or dominated by a particular hemisphere
what is divided into two hemispheres
the cerebrum - the largest part of your brain
define contralateral wiring
activity on the left-hand side of your body is controlled by the right hemisphere, whereas activity on the right-hand side of your body is controlled by the left hemisphere
what is the cerebral cortex
the outer layer of both hemispheres, which is subdivided into four lobes
name the four lobes
frontal lobe
parietal lobe
occipital lobe
temporal lobe
name the two cortex’s
motor cortex
sensory cortex
what is the role of the motor area
controls voluntary movements in the opposite side of the body
what is the role of the somatosensory area
sensory information, such as from the skin, is represented
what is the role of the visual area
each eye sends information from the right visual field to the left visual cortex and from the left visual field to the right visual cortex
what is the role of the auditory area
analyses speech based information
in which hemisphere are the language centres
the left hemisphere
name the two language centres
brocha’s area
wernicke’s area
what is the function of broca’s area
responsible for speech function
what is the consequence of damage to broca’s area
broca’s aphasia
symptoms: slow and laborious speech
CASE EXAMPLE - TAN
what is the function of wernicke’s area
responsible for speech comprehension
what is the consequence of damage to wernicke’s area
wernicke’s aphasia
symptoms: produce meaningless words
where is broca’s area located
the frontal lobe
where is wernicke’s area located
the temporal lobe
what is the result of damage to the motor area
loss of control over movements
what is the result of damage to the somatosensory area
amount of somatosensory area devoted to a particular body part denotes its sensitivity, i.e. receptors for our face and hands occupy over half of the somatosensory are
what is the result of damage to the visual area
damage to the left hemisphere can cause blindness in part of the right visual field of both eyes
what is the result of damage to the auditory area
may produce partial hearing loss, the more extensive the damage the more extensive the loss
where is the somatosensory area located
the parietal lobe
where is the motor area located
the frontal lobe
where is the auditory area located
the temporal lobe
where is the visual area located
the occipital lobe
where is information from the right visual field sent
the left visual cortex
outline the role of adrenaline in a fight or flight response
brings about the appropriate physiological changes necessary, which could include pupil dilation, increased heart rate and breathing etc
define the term gland
an organ that produces hormones
give an example of a gland
pituitary gland
thyroid
adrenal gland
pineal gland
pancreas
testes
ovaries
define the term hormone
a substance which circulates in the blood but only affects target organs
give an example of a hormone
ACTH
LH
FSH
thyroxine
cortisol
adrenaline
noradrenaline
melatonin
insulin
testosterone
progesterone
oestrogen
why is the nervous system so fast acting
both electrical and chemical transmission
define the function of the myelin sheath
protects the axon and speeds up transmission
define the function of a node of ranvier
speeds up transmission by forcing the impulse to jump across gaps
where does electrical transmission occur
within the neuron
where does chemical transmission occur
between neurons
define the function of dendrites
receive information from other neurons, called pre-synaptic neurons, or from the environment
define the function of the axon
carries electrical impulses
define the function of schwann cells
maintaining the peripheral nervous system
ao3: describe dougherty et al’s study and findings
reported on 44 people with ocd who had undergone cingulotomy
at 32 weeks, 30% had met the success criteria, 14% for partial response
ao3: describe petersen et al’s study
used brain scans to demonstrate how wernickes area was active during a listening task and how brocas area was active during a reading task
ao3: describe tulving et al’s study
revealed that semantic and episodic memories reside in different parts of the prefrontal cortex using brain scans
ao3: describe lashley’s study and findings
removed areas of the cortex in rats learning the route through a maze
no area was proven to be more important than any other area in terms of the ability to learn to the route, the process of learning seemed to require all parts of the cortex rather than being confined to a particular area
ao3: describe dick and tremblay’s findings
found that only 2% of modern researchers truly believe that language is strictly controlled by wernicke’s and broca’s areas
define hemispheric lateralisation
the idea that the two hemispheres are functionally different and certain mental processes and behaviours are mainly controlled by a certain hemisphere
give an example of a process which is lateralised
language
facial recognition
give an example of a process which is contralaterally wired
the motor area
define ipsilateral wiring
situated or appearing on or affecting the same side of the body
how is vision wired in the brain
both contralateral and ipsilateral
describe how vision is wired in the brain
the LVF of both eyes is connected to the RH and the RVF of both eyes is connected to the LH
what happens in a split brain operation
involves severing the connection between the RH and the LH, mainly the corpus callosum
this is a surgical procedure to reduce epilepsy
outline sperry’s procedure
11 split-brain individuals
image or word presented to their RVF or LVF
asked to respond to stimulus - either verbally or with left or right hand
outline sperry’s findings
when an image/word was presented to the participant’s RVF, the participant could describe what was seen, but they could not do this if the image/word was presented to their LVF
although participants could not give verbal labels to images projected to the LVF, they could select a matching object using their left hand
which part of the brain is severed in split-brain patients
the corpus callosum
if an image of a cat was projected to the LVF and an image of a dog was projected to the RVF, which would the split-brain participant describe
the dog
ao3: outline fink et al’s study and findings
used PET scans to identify which brain areas were active during a visual processing task in ‘normal’ participants
when asked to attend to global elements of an image (such as looking at a picture of a whole forest) regions of the RH were much more active
when required to focus on the finer detail (such as individual trees) the specific areas of the LH tended to dominate
ao3: outline neilson et al’s study and findings
analysed brain scans from over 1000 people and found that people used certain hemispheres for certain tasks, but there was no evidence of a dominant side, i.e. not artist’s/mathematician’s brain
define plasticity
the brains tendency to change and adapt as a result of experience and new learning
define synaptic pruning
as we age, rarely used connections are deleted and frequently used connections are strengthened
what age does synaptic formation happen
36 weeks gestation until 2 years
who conducted plasticity research into london taxi drivers
maguire et al
outline maguire et al’s research
london taxi drivers had significantly more volume of grey matter in their posterior hippocampus than the matched control group
part of the brain associated with spatial and navigational skills
as part of training, taxi drivers must complete ‘the knowledge’
the longer they had been working, the more pronounced the structural difference
who conducted plasticity research into medical students
draganski et al
outline draganski et al’s research
conducted brain scans on medical students three months before and after final exams
learning induced changes seemed to have occurred in the posterior hippocampus and the parietal cortex
who conducted plasticity research into a video game training group
kuhn et al
outline kuhn et al’s research
compared control group with a video game training group who played super mario for at least 30 minutes a day
significant increase in grey matter in hippocampus and cerebellum
what is functional recovery
the brains ability to redistribute or transfer functions usually performed by a damaged area, to other undamaged areas
how quickly does functional recovery occur
can occur quickly after trauma (spontaneous recovery) and then slow down after weeks or months
what happens in the brain during recovery
the brain rewires and reorganises itself by forming new synaptic connections
secondary neural pathways are activated
what three structural changes in the brain support recovery
axonal sprouting
denervation supersensitivity
recruitment of homologous areas
what is axonal sprouting
growth of new nerve endings which connect with other undamaged nerve cells to form new neural pathways
what is denervation supersensitivity
axons that do a similar job become aroused to a higher level to compensate for the ones that are lost
what is recruitment of homologous areas
specific tasks can be carried out by an equivalent part of another hemisphere
give an example of recruitment of homologous areas
damage to the brocas area would result in the same area of the right hemisphere carrying out its functions
ao3: outline bezzola et al’s research
demonstrated how 40 hours of golf training produced changes in the neural representations of movement in participants aged 40-60
using fMRI, the researches observed increased motor cortex activity in the novice golfers, suggesting more efficient neural representations after training
ao3: outline schneider et al’s research
revealed that the more time people with a brain injury had spent in education, the greater their changes of a disability-free recovery
40% of those who achieved DFR had more than 16 years education compared to about 10% of those that had less than 12 years education
what does fmri stand for
functional magnetic resonance imaging
what do firm’s detect
changes in blood oxygenation and flow which occur as a result of neural activity in parts of the brain
how do fmris know which part of the brain is active
when a brain area is more active it consumes more oxygen and so blood flow is directed to this area
what do fmris show
3d images (activation maps) which show parts of the brain involved in mental processes
what does eeg stand for
electroencephalogram
what doe eeg’s measure
electrical activity in the brain
how do eeg’s measure electrical activity
electrodes that are fixed to the scalp using a skull cap
what do scan recordings produced from eegs show
represents the brainwave patterns generated from actions of the neurons
how do clinicians use eegs as a diagnostic tool
unusual arrhythmic patterns of activity may indicate neurological abnormalities such as epilepsy or tumours
what does erp stand for
event related potentials
what do erp’s do
take raw eeg data to investigate cognitive processing of specific events
how do rep’s filter out unrelated brain activity
multiple readings are taken and averaged
what are post mortems
analysis of a persons brain following their death
what type of people have post mortem conducted on them
individuals with a rare disorder and experienced unusual deficits in mental processing or behaviour during their lifetime
what areas of the brain are examined in post mortem and why
areas of damage to establish likely cause of the affliction the person experienced
what may researchers conducting post mortem do
compare the individuals brain with a neurotypical one
what are biological rhythms governed by
exogenous zeitgebers
endogenous pacemakers
what are the three types of biological rhythm
circadian
infradian
ultradian
what are two examples of circadian rhythms
sleep/wake cycle
core body temperature
what is the exogenous zeitgeber of the sleep/wake cycle
daylight
what is the endogenous pacemaker of the sleep/wake cycle
internal biological clock (scn)
what is our biological clock called
suprachiasmatic nucleus
where is our scn located
above the optic chiasm which provides information about light from the eyes
roughly when does melatonin production increase
8pm
roughly when do melatonin levels peak
2-4am
the middle of the night
roughly when do melatonin levels fall
7am or early morning
who conducted a cave study into the sleep/wake cycle
siffre
who conducted a cave study into the sleep/wake cycle
siffre
outline the procedure of siffre’s study
spent extended periods of time in caves deprived of exposure to natural light and sound
what did siffre find about his sleep/wake cycle
his ‘free-running’ biological rhythm settled down to just beyond 24 hours (around 25 hours) though he did continue to fall asleep and wake up on a regular schedule
who conducted research in a ww2 bunker
aschoff and wever
outline aschoff and wever’s study
participants spent 4 weeks in a ww2 bunker deprived of natural light
what were the findings of aschoff and wever’s study
all but one of the participants (whose s/w cycle extended to 29 hours) displayed a circadian rhythm of 24-25 hours
what does research into the sleep/wake cycle suggest
suggests that the ‘natural’ s/w cycle may be slightly longer than 24 hours but it is entrained by exogenous zeitgebers
who studied the sleep/wake cycle by shortening the participants perception of 24 hours
folklard et al
outline the procedure of folklard et als study
12 participants lived in a cave for 3 weeks, over the course of the study, the researchers secretly and gradually sped up the clock so an apparent 24-hour day only lasted 22 hours
what were the findings of folklard et als study
only one of the participants was able to comfortably adjust to the new regime.
when is core body temp the highest
around 6pm
when is core body temp the lowest
4am
ao3: what range of s/w cycles did czeisler et al find
13-65
ao3: what did duffy et al suggest about s/w cycles
some people have a natural preference for going to bed early and rising early (‘larks’) whereas others prefer the opposite (‘owls’)
what are infradian rhythms
biological rhythms which last longer than 24 hours
what are ultradian rhythms
biological rhythms which last under 24 hours
how long does the menstrual cycle last
28 days
what happens when levels of oestrogen are high
an egg is released
roughly which day of the menstrual cycle is an egg released
day 14
what happens when levels of progesterone are high
the lining of the uterus is built up and maintained
give examples of infradian rhythms
the menstrual cycle
seasonal affective disorder (sad)
who studied the role of exogenous factors in a menstrual cycle
stern and mcclintock
outline stern and mcclintock’s study
studied 29 women with a history of irregular periods
samples of pheromones were gathered from 9 of the women at different stages of their menstrual cycles, via a cotton pad placed on
their armpit
the pads were treated, frozen and rubbed on the upper lip of the other participants
what were the findings of stern and mcclintocks study
68% women experienced changes to their cycle which brought them closer to their ‘odour donor’
what does sad stand for
seasonal affective disorder
what is sad
a depressive disorder with a seasonal pattern
what time of year do people with sad become depressed and why
symptoms are triggered during the winter months when the number of daylight hours becomes shorter
the lack of light in the morning means melatonin is secreted for longer, this has a knock-on effect on the production of serotonin
give an example of an ultradian rhythm
stages of sleep
how many stages of sleep are there and how long do they last
5 stages
altogether last 90 minutes
how can we differentiate the sleep stages
characterised by different brain waves which can be detected by an eeg
what brain waves are present in sleep stages 1 and 2
alpha waves
what brain waves are present in sleep stages 3 and 4
delta waves
what does rem stand for
rapid eye movement
what happens during rem sleep
Makes sense of information. Makes connections between previously stored and newly stored information, such as the periodic table, beatles lyrics
helps us deal with emotions - sleep therapy through dreaming
why is sleep therapy through dreaming so useful
some parts of brain (amygdala) are 30% more active than when awake
what happens during nrem sleep
fact based memory, maintains memories but also salvages those that appeared to be lost the night before
light sleep renews ability to learn new information by clearing the hippocampus
deep sleep allows storage and our ability to recall information
it is also involved in restocking our immune system
what stages of sleep are light sleep
one and two
what stages of sleep are deep sleep
three and four
ao3: what did penton-voak et al suggest
suggested that mate choice varies across the menstrual cycle
women generally prefered feminised male faces (representing kindness) when picking a partner for a long-term relationship.
however, during the ovulation phase women preferred more masculine faces (representing ‘good genes’ to be passed onto offspring)
ao3: what did terman find in relation to sad
found that the rate of sad is more common in northern countries, where the winter nights are longer, than southern countries
ao3: what did sanassi find about light therapy
light therapy is effective in reducing the effects of sad in about 80% of people
ao3: what did dement and kleitman find about rem sleep
monitored the sleep patterns of 9 adults in a sleep lab
brain activity was recorded on an eeg and the researchers controlled ev’s (caffeine, alcohol)
rem activity during sleep was highly correlated with the experience of dreaming
brain activity varied according to how vivid dreams were, and participants woken during dreaming could recall their dream
ao3: what did tucker et al find about duration of sleep
studied participants over 11 consecutive days and nights and found large differences between participants in terms of duration of each sleep stage, particularly stages 3 and 4
suggested that these differences are likely to be biologically determined
what is the scn and where is it located
a tiny bundle of nerve cells located in the hypothalamus in each hemisphere of the brain
when does the scn receive info
continues even when our eyes are closed
what does the scn do
passes information on day length and light to the pineal gland
what does the scn do in relation to melatonin production
info about light to the pineal gland, which secretes melatonin when there’s no light
who studied the scn in chipmunks
decoursey et al
what was decoursey et al’s procedure
destroyed scn connections in the brains of 30 chipmunks who were then returned to their natural habitats and observed for 80 days
what was the findings of decoursey et al’s studies
the s/w cycle of the chipmunks disappeared and by the end of the study a significant proportion of them had been killed by predators
what did ralph et al do
bred ‘mutant’ hamsters with a 20-hour s/w cycle
what were the findings of ralph et al’s study
when scn cells from the foetal tissue of mutant hamsters were transplanted into the brains of normal hamsters, their cycles also defaulted to 20 hours
who studied the scn in hamsters
ralph et al
what do exogenous zeitgebers do
reset our biological clocks through entrainment
define entrainment
the process of making something have the same pattern or rhythm as something else
what is the main exogenous zeitbeger in humans
light
what key processes does light affect
sleep wake cycle
blood circulation
hormone secretion
who studied light as an exogenous zeitbeger
campbell and murphy
what was the procedure of campbell and murphy’s study
15 participants woken at various times and a light pad was shone on the back of their knees
what did campbell and murphy hypothesise for their study
light may be detected by skin receptor sites.
what were the findings of campbell and murphy’s study
resulted in a deviation in the participants’ usual s/w cycle of up to 3 hours
what was the conclusion of campbell and murphy’s study
light is a powerful EZ that does not necessarily rely on the eyes to exert an influence
what is an effective way of beating jet lag
adapting to local times for eating and sleeping (rather than responding to own feelings of hunger and fatigue)
when do circadian rhythms begin
6 weeks of age
when are rhythms entrained
16 weeks of age
ao3: outline miles et al’s study and findings
studied a young man, blind from birth, with a circadian rhythm of 24.9 hours
despite exposure to social cues, his circadian rhythm could not be adjusted and consequently he had to take sedatives and stimulants to keep pace with the 24hr world
