Biopsychology Flashcards
define NS
consists of CNS and PNS
define CNS
consists of the brain and spinal chord
define PNS
sends info from the environment to the CNS and transmits info from the CNS to the muscles and glands within the body
define somatic NS
transmits info from receptor cells in the sense organs to the CNS and receives info from the CNS that directs muscles to act
define autonomic NS
transmits info to and from internal organs - operates involuntarily and is divided into sympathetic and parasympathetic NS
give the two main functions of the NS
- to collect, process and respond to info in the environment
- to co-ordinate the working of diff organs and cells in the body
what differentiates the human brain from that of other mammals
the outer layer (cerebral cortex)is highly developed
what is the spinal chord responsible for
reflex actions
what does the endocrine system do
works alongside NS to control vital functions in the body
give some differences between the NS and endocrine system
NS - fast - brief effects - electrochemical signals (AP) via nerves endocrine system - slow - long lasting effects - hormonal signals via bloodstream
what is the master gland and what does it do
pituitary gland - controls the release of hormones from all other glands in the body
describe the sequence of events that occurs in the NS following the identification of a threat (fight or flight)
- sympathetic NS triggered by hypothalamus
- pituitary gland releases ACTH to trigger adrenal glands
- adrenaline is released, changing various bodily functions
give some changes to bodily functions following the release of adrenaline
- increased HR
- vasoconstriction near digestive organs to inhibit digestion
- pupils dilate
- inhibited saliva production
describe the sequence of events that occurs in the NS after a threat has passed (fight or flight)
- parasympathetic system activates to calm body
- HR decreases
- stimulates saliva production
- pupils constrict
- stimulates digestion
define gland
organ in the body that synthesises and releases substances such as hormones
define hormone
chemical messenger produced by glands that is secreted directly into the bloodstream
define fight or flight response
the way an animal responds when stressed in which the body becomes physiologically aroused in readiness
define adrenaline
a hormone produced by the adrenal glands which is part of the body’s immediate street response system
define neurone
basic building block of NS which transmit info through chemical and electrical signals
define sensory neurone
neurone that transmits sensory info from the PNS to the CNS
define motor neurone
neurone that connects CNS to effectors such as muscles and glands
define relay neurone
neurone that connects the sensory and motor neurones to each other or other relay neurones
what structures do all neurones possess
- cell body (contains organelles such as the nucleus)
- dendron (transmit impulses towards cell body)
- axon (transmit impulses away from cell body)
- synaptic bulb
what structure do some neurones possess
myelin sheaths
give the advantage associated with myelin sheaths
- increases the rate of transmission of an impulse
- allows impulse to jump between nodes of Ranvier
define synaptic transmission
process by which neighbouring neurones communicate with each other by sending info in the form of chemicals across the synaptic cleft that separates them
define neurotransmitter
chemicals released from synaptic vesicles that relay signals across the synapse from one neurone to another
what are the two types of neurotransmitter function
- excitatory
- inhibitory
define excitation
when a neurotransmitter, such as noradrenaline, increases the positive charge of the postsynaptic neurone, increasing the likelihood that the neurone will fire and pass on the electrical impulse
define inhibition
when a neurotransmitter, such as serotonin, increases the negative charge of the postsynaptic neurone, decreasing the likelihood that the neurone will fire and pass on the electrical impulse
describe the process of synaptic transmission
- impulse travels down the axon of the presynaptic neurone
- vesicles inside the presynaptic neurone which containing neurotransmitter, fuse with the membrane of the presynaptic neurone
- neurotransmitters from the vesicle are released into the synaptic cleft
- neurotransmitters bind and activate the receptors on the postsynaptic neurone
- impulse travels down the axon of the postsynaptic neurone
what happens to leftover neurotransmitter in the synaptic cleft
- sucked back up into the presynaptic neurone through the process of re-uptake
- if cell cannot perform re-uptake, enzymes are released to break down left over neurotransmitters
what is an advantage of neurotransmitter re-uptake
saves energy as neurotransmitters can be recycled
define summation
when combined influences on a neurone are summed, the overall charge determines whether neurone fires or not
what can result from an imbalance in neurotransmitters
mental illness
define localisation of function
T that diff areas of the brain are responsible for diff Bs and processes
define motor area
a region of the frontal lobe involved in regulating movement
define somatosensory area
area of parietal lobe that processes sensory info such as touch
define visual area
part of occipital love that receives and processes visual info
define auditory area
located in temporal lobe, concerned with analysis of speech-based info
define Broca’s area
area of frontal lobe in L hemisphere, responsible for speech production
define Wernicke’s area
area of temporal lobe in L hemisphere responsible for language comprehension
what is the holistic T of the brain
all parts of the brain are involved in the processing of thought and action
what caused a change in the holistic T of the brain
scientists such as Broca and Wernicke discovered that specific areas of the brain were associated with particular physical and psychological functions
how is the brain divided
into two hemispheres - L and R
which side of the body does the LH control
right side
which side of the body does the RH control
left side
name the four lobes of each hemisphere
frontal lobe
parietal lobe
temporal lobe
occipital lobe
where is the motor area located
back of the frontal lobe
where is the somatosensory area located
front of parietal lobe
where is the visual area located
occipital lobe
where is the auditory area located
temporal lobe
give the function of the motor area and what could happen if it was damaged
controls voluntary movement, damage may result in loss of control over fine movements
give the function of the somatosensory area and what could happen if it was damaged
where sensory info from skin is represented, damage may result in
give the function of the visual area and what could happen if it was damaged
where visual info is received and processed, damage could result in blindness in parts of the visual field
give the function of the auditory area and what could happen if it was damaged
where speech-based info is analysed, damage could result in partial hearing loss
what could damage to Broca’s area result in
Broca’s aphasia - slow speech that lacks fluency
what could damage to Wernicke’s area result in
Wernicke’s aphasia - nonsense word production
define plasticity
the brain’s tendency to change and adapt as a result of experience and new learning
define functional recovery
form of plasticity following damage through trauma, in which the brain redistributes or transfers functions usually performed in damaged area to other undamaged areas
describe what happens to the number of synaptic connections in the brain as we age
- during infancy, brain experiences rapid growth of synaptic connections
- peaks at 15,000 at 2-3 y/o
- as we age, rarely used connections are deleted whilst frequently used ones are strengthened
generally, what does research into brain plasticity suggest
at any time in life existing neural connections can change, or new neural connections can be formed as a result of learning and experience
give a research study into plasticity
Maguire et al (2000)
- studied brains of London taxi drivers
- take a test of recall to assess their knowledge of routes
- found signif higher vol. grey matter in posterior hippocampus when compared to control group
- hippocampus associated with development of spatial and navigation skills
- also found the longer on the job, the more pronounced this structural diff
explain the study and findings of Draganski et al (2006)
- imaged the brains of medical students 3mths before and after their final exams
- learning-induced changes seen in hippocampus posterior and parietal cortex as a result of the exam
describe the process of functional recovery following trauma
- undamaged areas of brain take over the functions of damaged areas
- can occur quickly (spontaneous recovery)
- slows down after several weeks
- individual may require rehabilitative therapy to further recovery
what three things happen to the brain during recovery
- axonal sprouting (growth of new nerve endings to form new pathways)
- reformation of blood vessels
- recruitment of homologous areas (on opposite side of brain to perform specific tasks)
define hemispheric lateralisation
idea that two halves of brain are functionally diff and certain mental processes and B are mainly controlled by one H rather than the other
define split-brain research
series of studies involving epileptic patients who had experienced a surgical separation of H allowing researchers to investigate the extent to which brain function is lateralised
define biological rhythms
distinct patterns of changes in body activity that conform to cyclical time periods which are influenced by internal body clocks as well as external changes the environment
define circadian rhythm
type of bio rhythm, subject to a 24hr cycle, which regulates a no. of body processes such as the sleep.wake cycle
define infradian rhythm
type of bio rhythm with a frequency of less that one cycle in 24hrs, such as menstruation
define ultradian rhythm
type of bio rhythm with a frequency of more that one cycle in 24hrs, such as the stages of sleep
define endogenous pacemaker and give an examples
internal body clocks that regulate bio rhythms e.g. SCN
define exogenous zeitgeber and give two examples
external cues that may affect/ entrain bio rhythms e.g. light, meal times
how does an fMRI work
- detects changes in blood oxygen and flow to certain parts of the brain during neural
- when an area is more active it consumes more oxygen to meet demands
- produces a map to show that which parts of the brain are active
- important investigating localisation of function
how does an EEG work
- measures electrical activity within the brain via electrodes on the head
- represents brainwave patterns and provides overall account of brain activity
- used to diagnose epilepsy, tumours and sleep disorders
how does an ERP work
- brains electrophysiological response to specific cognitive sensory or motor events is isolated
- statistical analysis of EEG
how does a post mortem work
- analysis of the brain after death to determine whether abnormal behaviour can be linked to brain abnormalities
give two strengths associated with fMRI
- non-invasive
- high spatial resolution
give two weaknesses associated with fMRI
- expensive
- low temporal resolution
give two strengths associated with EEG
- contributed to many diagnoses
- high temporal resolution
give two weaknesses associated with EEG
- not useful for pinpointing exact location of activities
- can be uncomfortable
give two strengths associated with ERP
- high temporal resolution
- high specificity of measure
give two weaknesses associated with ERP
- lack of standardisation
- background noise and other EVs must be absent (which is difficult to achieve)
give two strengths associated with post mortem
- improves medical knowledge
- helps generate hypotheses for studies
give two weaknesses associated with post mortem
- ethical issues with consent
- individual must be dead
outline the role of endogenous pacemakers on the sleep/ wake cycle
- SCN helps maintain sleep/ wake cycle
- SCN passes info to the pineal gland which produces melatonin (which induces sleep)
- melatonin drops in the morning as cortisol rises due to the SCNs response to light
outline Siffre’s study
- investigated role of exo and endo factors on the circadian rhythm
- removed all exo factors by living in a cave ( no light or clocks)
- found evidence for role of endo controlling sleep wake cycle (which he evidenced was just over 24 hours)
- showed that exo entrain rhythms to match everyday life
outline Aschoff and Wever’s study and how does it agree with Siffre’s findings
- had pps live in WW II bunker for four weeks
- all but one pps circadian rhythm was 24-25 hrs
- supports Siffre by suggesting the natural sleep/ wake cycle may be longer than 24 hours
- rhythms entrained by light and mealtimes to match everyday life
give an advantage of the research done into the influence of endogenous pacemakers on biological rhythms
- practical app with drug treatments
- knowledge of times of day when blood is stickiest, BP is highest and blood vessels are most flexible
- can help to improve efficacy of drug treatments
- base administration on these times to change the dispersion and absorption of certain drugs
explain the practical application of research into the circadian rhythm
- better understanding of the consequences from disruption of the cycle
- shift workers have reduced concentration at 6 AM
- accidents are more likely to occur
- has economic implications for shift work
- e.g. how workers are managed to increase their productivity
outline the menstrual cycle as an example of an infradian cycle
- approx 24-28 days
- this is the time between the first day of the period and the day before the next period
- regulated by the hormone oestrogen (which causes egg release) and progesterone (which thickens womb lining)
outline Stern and McClintock’s study
- 29 women with history of a irregular periods
- sample of pheromones taken from 9 of those women at different stages of their cycle
- a pad was placed under their armpit for more than 8 hrs
- pad then treated with alcohol and frozen
- pads were rubbed on the lip of the 20 women
- found that 68% had changes in the cycle which were closer to that of their odour donor
outline one issue with Stern and McClintock’s study
- argued that many factors contribute to changes in cycle e.g. stress and diet
- these act as CVs
- therefore changes in synchrony are seen as no more than what would have been expected to occur by chance
give two issues with the studies by Siffre and Aschoff and Wever
small sample size
- pps may not accurately represent wider population
- limits to the extent of meaningful generalisations that can be made from these findings
individual differences
- larks and owls
- even Siffre found his sleep wake cycle was slower as he aged (towards 25 hs)
- illustrates that even the in the same person, pp factors vary
- may prevent general conclusions been drawn
outline stages 1 and 2 of the sleep cycle
- light sleep
- brain wave patter is slow and rhythmic
- theta waves (low amplitude, high frequency)
outline stages 3 and 4 of the sleep cycle
- deep sleep
- slow wave stages
- associated with delta waves
outline stage 5 of the sleep cycle
- REM/ dream sleep
- body paralysed
- brain activity resembles that of someone who is awake
outline the study by Dement and Kleitman
- monitored the sleep patterns of 9 adults in a lab
- brain activity was recorded on an EEG
- caffeine and alcohol were controlled
- found are REM to be highly correlated with dreams
- pps woken in this stage had accurate recall of their dreams
give two methodological issues with the Dement and Kleitman study
small sample size
- creates limitations to the extent of which generalisations can be made and applied
study conducted in our lab
- this is a different environment in which many individuals sleep
- may act as an EV and influenced findings
outline the procedure of Sperry’s experiments
- image/ word was projected onto the screen in the pps right visual field (which is processed in the left hemisphere)
- same/ different image/ word projected into the left visual field (which is processed in the right hemisphere)
- corpus callosum shares info between hemispheres making the picture/ phrase complete
- split brain patients could not convey this info between hemispheres
give two strengths of Sperry’s experiments
paved way for more split brain studies
- significant contribution to the knowledge of brain function
- suggesting left hemisphere geared towards analytic and verbal tasks whilst the right hemisphere performs spatial tasks
good methodology
- only one visual field was able to see an image/ word
- image/word flashed quickly
- had high control and standardised methods (make replications easier and increase confidence in findings)
- managed to isolate information
- allowed researchers to see what each hemisphere could and could not do
- able to conclude the hand and visual field corresponds to the opposite hemisphere
give a limitation of Sperry’s experiments
- sample size was too small (11 pps) and unique (had epilepsy)
- some may have had more hemispheric separation than others
- argued this uniqueness may have influenced results
- overall, creates issues with generalisability findings
explain Sperry’s finding: when object shown to the left visual field pps could not describe what was seen and would say “nothing” when asked
- info seen in the right visual field is sent to left hemisphere with the language centre
- info in the left visual field sent to the right hemisphere which is non-verbal so cannot produce the right vocab
- left hemisphere saw black slide so says “nothing”
explain Sperry’s finding: image shown to left visual field, pp could pick up object that matched or was similar to image with their left-hand
- whilst right hemisphere cannot articulate the right language it can understand what was seen
- through non-verbal means image can can be identified
explain Sperry’s finding: if two words presented, one in each visual field, pp would write one and say the other e.g write ‘key’ and say “ring”
- left hemisphere sees ‘ring’ so says “ring”
- hemispheres shown no awareness to combine knowledge
- support idea hemispheres work independently
explain Sperry’s finding: when asked to match faces from a series of other pictures, pictures processed by the right hemisphere could be selected whilst those in the left hemisphere were ignored
- facial recognition centre localised in right hemisphere
- lack of recognition in left hemisphere suggests absence of centre
give a strength of Maguire’s methodology
- high control over EVs
- sample consisted of all males whom were matched on important factors
- reduced the number of EVs that may have affected the results of the study
- can be confident that the findings are valid
give a strength of Draginski’s study
- studied a real-world event
- studied the brains of medical students
- important because results are more likely to reflect what would be seen in real-life
- study therefore has high ecological validity
give a weakness of research into plasticity
- uses small samples
- e.g. Maguire’s sample was all-male
- results may not reflect those seen in women and children
- limitations in the extent to which findings can be generalised to wider population
suggest some supporting for localisation of function
- case study evidence from HM and KF who had brain injuries and could no longer perform certain functions
- data collected from scans such as Tulving and Petersen and Petersen (which is highly scientific and nomothetic)
give an application of research into localisation of function
- practical app derived from supporting evidence
- e.g. solving dementia and helping people live with it
- working to understand and explain other neurological disorders such as OCD
give a limitation of evidence into the localisation function and a piece of counter evidence to support the weakness
- uses reductionist theories and ideas
- certain cognitive functions may be too complex to lateralise
- lashley suggested the law of equipotentiality
- remove 10 to 50% of rat brains
- found no area to be more important in terms of rats ability to learn a maze
- suggested learning is too complex to be localised and activities require the involvement of the entire brain
