Biopsychology Flashcards
What do biopsychologists assume that human behaviour is caused by?
on the interaction between nature & nurture
What is the nervous system?
the internal communication system of the human body
What is the function of the nervous system?
to collect, process & respond to information in the environment by coordinating the working of different organ and cells
Which are the two organs which make up the central nervous system?
- brain
- spinal cord
What is the function of the CNS?
passage messages to and from the brain & connects nerves to PNS
What are the 2 main nervous systems?
- central nervous system
- peripheral nervous systsem
What is the functions of the peripheral nervous system?
transfers messages via neurons (nerve cells), to and from the central nervous system
What are the two components of the peripheral nervous system?
- somatic nervous system
- autonomic nervous system
What is the function of the somatic nervous system?
responsible for carrying sensory & motor information to and from the spinal cord
What is the function of autonomic nervous system?
controls vital functions in the body which are involuntary
eg. breathing, heart rate, digestion, sexual arousal & stress responses
What are the two main division of the ANS?
- sympathetic nervous system
- parasympathetic nervous system
What is the function of the sympathetic nervous system?
generally prepares the body to expend energy for fight or flight
What is the function of the parasympathetic nervous system?
maintains & conserves body energy & functions
What word would you use to describe the relationship between actions the sympathetic nervous system and the parasympathetic nervous system? What does this mean?
antagonistic - they usefully work in opposition to each other
What are 3 physiological reactions which happen during fight or flight?
- increase heart rate
- dilates bronchi - increased breathing rate
- weak stimulation of saliva - dry mouth
What is a neuron?
a cell which is responsible for transmitting electrical and chemical messages across the nervous system
What is a synapse?
the gap at the end of the axon of one neuron and the dendrites of the next neurons
What is synaptic transmission?
refers to the process by which an electrical impulse passes across the synapse from one neuron to another neuron
What are neurotransmitters?
chemical substances that play a major role in the functioning of the nervous system by transmitting electrical impulses
What are the 3 types of neuron?
- sensory
- relay
- motor
In a neuron, what is the structure & function of the cell body?
includes the cell nucleus, which contains the genetic material of the cell
In a neuron, what is the structure and function of dendrites?
(in relay & motor neurons) they extend from the cell body, carrying nerve impulses from other nuerons towards the cell body
In a neuron, what is the structure and function of an axon?
carries impulses away from the cell body towards the axons terminals
In a neuron, what is the structure and function of the myelin sheath?
a fatty layer which protects the axons & speeds up electrical impulses
In a neuron, what is the structure and function of the synaptic knob?
found at the end of axons, before the synapse & contain vesicles of neurotransmitters
Which type of neuron does not have a myelin sheath?
relay neurons
What are the two types of effect that neurotransmitters can have on the neighbouring neuron?
- excitatory
- inhibitory
What is another phrase for the process of an electrical impulse moving down a neuron?
action potential
define hormone.
chemical messenger which is transported in the bloodstream, which transfers information around the body
What is the function and structure of a sensory neuron?
- carry messages from receptors in the PNS to the CNS
- longer dendrites, shorter axons & cell body in the middle of axon chain
What is the function and structure of relay neurons?
- pass on messages between sensory neurons to motor neurons
- found only within the CNS
- short dendrites
- axon with no myelin sheath
- cell body is sometime in middle of axon chain
What is the function and structure of a motor neuron?
- connect the CNS to effectors (muscles & glands)
- long axon has large cell body with short dendrites at end (like a star)
What is the process of neuron firing? (electrical transmission)
- when in a resting state, the inside of the cell is negatively charged.
- when a neuron is activated by a stimulus, the inside of the cell becomes positive for a split second causing ACTION POTENTIAL for a moment
- this creates an electric impulse that travels down the axon towards the end of the cell
What is the process of synaptic transmission?
- an electrical impulse is transferred to another neuron via the synaptic gap
- at the end of presynaptic neuron, there are synaptic vesicles
- as the electrical impulse reaches the end of the axon, it causes the vesicles to open
- neurotransmitters are released into the gap and bind to the receptor of the postsynaptic neuron & is activated
- the neurotransmitters are converted into an electrical charge and causes neuron firing to occur
- neurotransmitters left in the synapse are taken back to the presynaptic neuron, so that the response doesn’t repeat
What are presynaptic and postsynaptic neurons?
presynaptic - before the synapse
postsynaptic - after the synapse
What does it mean for a neurotransmitter to have an excitatory effect on the neighbouring neuron?
increases the positive charge of the neuron and making it more likely to fire
What does it mean for a neurotransmitter to have a inhibitory effect on the neighbouring neuron?
increases the negative charge of the neuron and making it less likely to fire
What is the endocrine system?
a system which is made up of glands that produce & secrete hormones to regulate the activity of cells or target organs
after fight or flight, what is the role of the parasympathetic nervous system?
return body to normal functioning
What hormone does the thyroid gland produce?
thyroxine
What does is thyroxine responsible for?
regulates heart rate & the body’s metabolic rate
What is the role of the hypothalamus in the endocrine system?
controls the functioning of the pituitary gland
What is the pituitary gland also known as?
master gland
What is the role of the pituitary gland?
controls hormone secretion in other glands
What is the role of adrenaline during fight or flight?
- stressful situation causes the body moves from parasympathetic mode
->sympathetic mode - pituitary gland release the hormone ACTH
- this stimulate the adrenal gland to release adrenaline into the bloodstream
- adrenaline put the body on an alert mode to deal with stress
- once the stressful situation is dealt with the parasympathetic system bring the body back to rest & digest state
what is localisation of function?
where different areas of the brain are responsible for different or processes
Where is the motor area found in the brain?
back of front lobe (in both hemispheres)
What is the function of motor area?
controls voluntary movement in the opposite side of body
What is the function of the somatosensory cortex?
where sensory information from the skin is detected
Where is the somatosensory cortex found in the brain?
at the front of both parietal lobes
What is the function of the visual cortex?
processing visual information
eg. information from right visual field goes to left visual cortex & left visual field -> right visual cortex
Where is the visual cortex found in the brain?
in the occipital lobe
What is the function of the auditory cortex?
processes auditory informtation
Where is the auditory cortex located in the brain?
temporal lobes
What is the function of language centres?
analyses speech-based information
What are the two language centres?
- Wernicke’s Area
- Broca’s Area
What is the function of Wernicke’s Area?
understanding language
What is the function of Broca’s Area?
producing speech
Where are the two language centres located in the brain?
Broca’s area - frontal lobe
Wernicke’s - temporal lobe
What is a strength of localisation of function? (as a theory)
evidence from neurosurgery - 44 people with OCD underwent a cingulotomy (isolates a region called cingulate gyrus, which has been implicated in OCD)
30% said there was a successful outcome from the surgery
- suggests that behaviours associated with serious mental disorders may be localised
What properties of the brain oppose the localisation of function theory?
plasticity & functional recovery
What is the Petersen’s brain scan evidence?
used brain scans to demonstrate how Wernicke’s area was active during a listening task & Broca’s area was active during a reading task
How did Lashley’s research disagree with the localisation of function theory?
removed areas of the cortex in rats that were learning a route through a maze
no area was proven to be more important than any other area in terms of the rats’ ability to learn the route
seemed to require every part of the cortex
What is meant by hemispherica lateralisation?
idea that the 2 halves of the brain are functionally different & different processes/behaviour are controlled different hemispheres
Which hemisphere is responsible for the which side of the body?
left hemi - right side
right hemi - left side
Which hemisphere contains the language centres?
left
Which hemisphere is immunopotentiating?
left hemisphere
Which hemisphere is immunosuppressive?
right hemisphere
Which hemisphere has better face recognition & drawing abilities?
right hemisphere
Who were the split brain patients?
a group of patients who had a corpus callosotomy, so their 2 hemispheres had been separated & weren’t communicating with each other
Why did split brain patients have a corpus callosotomy?
as a type of epilepsy treatment, to control seizures
What was Sperry’s research into lateralisation of function?
He compared 11 split brain patients to others without hemisphere separation.
both groups carried out activities which involved naming and picking up objects in LVF or RVF
What were the findings of Sperry’s research into lateralisation of function (describing what they see)?
- object was shown to a split brain patient’s RVF (linked to Lhemi) & patient could describe what was seen, as Lhemi has language functions. if object was shown to the LVF, patient says there is nothing there
- the control group were always able to name the object
What were the findings of Sperry’s research into lateralisation of function (recognition by touch)?
- patient was shown an object to their RVF & asked to pick object up with their left hand, they wouldn’t be able to select the object as it was seen by Lhemi & left hand is controlled by the Rhemi
- control group were always able to select object
What were the conclusion from Sperry’s study?
hemispheres do seem to have lateralised function, especially for language & drawing abilities
What are advantages of lateralisation of function?
- enables 2 tasks to be performed simultaneously eg. rogers showed that lateralised chickens could find food while watching for predators
- left hemi = immunopotentiating & right hemi = immunosuppressive
What is a disadvantage of lateralisation of function?
Although some functions may be lateralised, Nielsen’s research suggests that people do not have a dominant side of their brain, which creates a different personality
What are 2 strength of Sperry’s research?
- research support from Gazzaniga which showed split brain participant actually perform better than connected brains on certain tasks eg. identifying odd object. This supports sperry’s finding that the left hemi & right hemi are distinct
- standardised procedures = good internal reliability
What are 2 limitations of Sperry’s research?
- low population validity: sample was 11 patients
- lack of ecological validity due to nature of tasks - as in real life patients can adjust visual position so info goes to both hemis.
What is meant by brain plasticity?
the tendency of the brain to change & adapt as a result of experience & new learning
What is meant by functional recovery?
the brain’s ability to redistribute or transfer functions usually performed by a damaged area to a different undamaged area
What was Maguire’s research into brain plasticity?
Studied the brains of London taxi drives & found significantly more volume of grey matter in the posterior hippocampus, than in a matched control group.
This shows that the learning experience of taxi drivers has altered the structure of their brain
What are 3 main structural changes in the brain as part of functional recovery?
- axonal sprouting
- denervation supersensitivity
- recruitment of homologous
What is axonal sprouting?
growth of new nerve endings which connect to other undamaged nerve cell to form neuronal pathways
What is denervation supersensitivity?
axons that do a similar job, they become aroused to a higher level to make up for lost axons
What is recruitment of homologous?
recruiting areas on the opposite side of the brain to carry out functions
What is a strength of brain plasticity?
it may be a life-long ability - Bezzola found 40 hours of golf training changes neural representations of movement in 40-60 year olds
What is a limitation of brain plasticity?
60-80% of amputees experience phantom limb syndrome as a result of brain plasticity, which can be unpleasant & painful
What is a strength of functional recovery?
real world application - understanding functional recovery, this has contributed to neurohabilitation eg. constraint induced movement therapy
What is a limitation of functional recovery?
Schneider found that level of education influences recovery rates, as the more time people with a brain injury spent in education, the greater their chances of a disability free recovery
What are the 4 methods of studying the brain?
- fMRI
- EEG
- ERP
- post-mortem examination
What is an fMRI scan?
detects changes in blood oxygenation & flow that occur as a result of brain activity in specific parts of the brain
What are 2 strengths of an fMRI?
- does not rely on radiation
- high spatial resolution (clear picture)
What are 2 limitations of fMRI?
- expensive
- poor temporal resolution (not in real time)
What is an EEG?
measures the brain’s electrical activity, via electrodes that fixed to the ptcpnt’s scalp using a skull cap
What are strengths of an EEG?
- used in studying stages of sleep & conditions like epilepsy, where both involve different levels of electrical activity
- high temporal resolution
What is a limitation of EEG?
not useful for determining the exact source of neural activity
What is an ERP?
the same as an EEG, although all extraneous brain activity from the recording is filtered out, so info is only regarding a specific stimulus
What is a strength of an ERP?
- high temporal resolution
- more specificity to the measurement of neural processes than using raw EEG data
What are limitations of an ERP?
- lack of standardisation means that it difficult to confirm findings
- filtering out extraneous material is not always easy
What is a post-mortem examination?
analysis of a person’s brain following their death
What is a strength of a post-mortem examination?
been vital in establishing roles within the brain as Broca & Wernicke both relied on post-mortem studies to identify links between lanaguge, brain & behaviour
What is a limitation of post-mortem examinations?
- participants may not be able to provide informed consent
- it is hard to determine causation, when the individual is not alive
What is a circadian rhythm?
biological rhythm that happens every 24 hours
What is an ultradian rhythm?
a biological rhythm which occurs many times a day
What is an ultradian rhythm?
a biological rhythm which happens less than every day
What is an exogenous zeitgeber?
external factors that affect our biological rhythms
What is an endogenous pacemaker?
internal body clocks that regulate many of our biological rhythms
What is the endogenous pacemaker which governs our sleep/wake cycle?
a biological clock called the SCN
What influences the SCN?
exogenous zeitgebers (light)
What does the SCN do?
triggers the release of cortisol to help you wake up in the morning and releases melatonin, to help you sleep
What was Folkard’s clock study into circadian rhythms?
- studied 12 people who agreed to live in a cave for 3 weeks
- they went to sleep at 11:45pm and woke up 7:45pm
- Folkard sped the clock up so eventually each day lasted 22 hours
- only 1 person adjusted
What was found in research about circadian rhyhthms and age?
- circadian rhythms differ with age
- teenages experience ‘phase delay’ where they sleep/wake cycle is pushed back so they stay awake later & wake up later
- Oxford uni found that when school started at 10am results and behaviours improved
What happened in Siffre’s cave study?
Siffre spent long periods of time in a cave, to study the effects of his own biological rhythms
- he was deprived natural light & sound
- he came out mid-september believing it to be mid-august
