biop2 Flashcards
what are the divisions of the nervous system, and what do these comprise of?
central (complex processing + decision making) into brain and spinal chord
+
peripheral (info from senses to CNS + from CNS to glands/muscles) into:
Somatic (voluntary movements, info from senses to CNS)
+
Autonomic (involuntary e.g. heart beat, to and from organs) into:
sympathetic (fight/flight, increase hr/br, inhibit digestion/saliva production, dilate pupils/contract rectum)
+
parasympathetic (rest/digest, decrease hr/br, stimulate digestion/saliva production, constrict pupils/relax rectum)
describe the process of synaptic transmission
electrical impulses reach presynaptic neuron terminal
triggers vesicles containing neurotransmitter to fuse with PSN membrane, released into synapse by exocytosis
neurotransmitters diffuse across synaptic cleft + bind to receptor on PSN membrane
leads to excitation or inhibition- reuptake channels/ destroyed by enzymes
whats the function of the pituitary gland?
master gland, controls release of hormones from all other endocrine glands
whats the function of the pineal gland?
melatonin
biological rhythms like sleep/wake cycle
whats the function of the hypothalamus?
stimulates release of hormones from pituitary gland
whats the function of the thyroid gland?
thyroxine
regulates metabolism
whats the function of the adrenal medulla?
adrenaline
fight/flight response
whats the function of the adrenal cortex?
cortisol
release glucose to provide energy
whats the function of the ovaries?
oestrogen
menstrual cycles, pregnancy
whats the function of the testes?
testosterone
development of male sex characteristics in puberty, muscle growth
describe the fight/flight response
stresser
when danger percieved by amygdala, sends stress signal to hypothalamus
hypothalamus activates sympathetic nervous system
stimulates adrenal medulla to release adrenaline
what are the 6 effects of adrenaline?
increase heart rate breathing rate inhibit digestion inhibit saliva production dilate pupils contract rectum
where is the motor area of the brain?
frontal lobe
both hemisphere
where is the somatosensory area?
parietal lobe
both hemispheres
where is the visual area?
occipital lobe
both hemispheres
where is the auditory area?
temporal lobe
both hemisphere
Where is the brocas area?
frontal lobe
left hemisphere
where is wernickes area?
temporal lobe
left hemisphere
whats the difference between function of brocas and wernickes area?
brocas=production of speech
wernickes=understanding speech
what is evidence supporting localisation in the brain?
damage to broca’s area result in impaired ability to produce speech (braca’s aphasia)
damage to wernickes area results in impaired ability to understand speech
(and phineas gage)
whats 1 strength and 1 limitation of research supporting localisation in the brain?
Broca’s patient tans MRI found other areas also associated with failure in speech production
biologically reductionist bc reduce complex human behaviour to one area
who did split brain research and whats the aim procedures and results?
Sperry
aim: see whether hemispheres performed tasks independently
method: split brain patients. present visual info to left or right (info presented to right is received by left and visa versa)
results: those presented to right visual field could be named verbally (because left controls language)
those presented to left visual cant be named verbally, but can point with left hand (bc left field interpreted by right brain, which controls left side of body)
name a strength and a limitation of Sperry’s research
standardised procedure ensure only 1 field at a time
small sample bc split brain patients are rare + disconnection greater in some than others
what is brain plasticity?
neural connections can change/ new ones can form (e.g. by axonal sprouting)
what is McGuire’s evidence for plasticity?
maguire et al- london taxi drivers more grey matter in posterior hippocampus- spatial learning changed brain structure, +ve correlation between size and time as taxi driver
what is functional recovery?
brains ability to transfer/redistribute functions to other parts of the brain by forming new synaptic connections
what is 1 strength and 1 limitation of research into plasticity and functional recovery?
contributes to field of neurorehabilitation
plasticity reduces with age
what are the 4 ways of studying the brain?
functional magnetic resonance imaging (MRI)
electroencephalography (eeg)
event related potentials (erp)
post-mortem exam
whats does an fmri show, whats 1 strength and 1 limitation of this?
oxygenated blood flow
non invasive
overlooks networked nature of brain + doesn’t directly measure neural activity, just blood flow
whats does an eeg show, whats 1 strength and 1 limitation of this?
electrical activity
activity in real time rather than still image
cant reveal deeper brain structures/pinpoint where activity is
whats does an erp show, whats 1 strength and 1 limitation of this?
electrical activity triggered by stimulus
shows how processing affected by stimuli
difficult to pick out from other neural activity
whats does a post mortem exam show, whats 1 strength and 1 limitation of this?
dissection of brain
can examine deeper regions
many varying things can cause death that would affect the brain
define biological rhythms
cyclical changes in the way biological systems
what are circadian rhythms, give an example.
once a day e.g. sleep wake cycle
what are infradian rhythms, give an example.what are circadian rhythms, give an example.
last longer than 24 hours e.g. menstrual cycle
what are ultradian rhythms, give an example.
last less than 24 a day e.g. sleep stages
who did research into circadian rhythms, what did they do and what did they find?
siffre
6 months in cave
no external stimuli to judge time (no light/temp changes)
he decided when to sleep + blood pressure/breathing rate monitored
originally chaotic, then settled to 24.9 hour cycle
suggests there is an endogenous pacemaker producing the cycle, but a need for exogenous zietgebers to keep it more in sync
whats the difference between endogenous pacemaker and exogenous zietgeber?
pacemaker= internal body clock zietgeber= external factors in environment that reset biological rhythms through a process known as entrainment
what is a strength and a limitation of siffres research into circadian rhythms?
case study- detailed + controlled environment
artificial + body may act differently as only on one person
whats the main endogenous pacemaker, and whats 1 strength and limitation of research into this?
suprachiasmatic nucleus (SCN) recieves info from the optic chiasm about light, allowing bio clock to adjust
decoursey et al removed SCN of 30 chipmunks and sleep wake cycle disappeared
many died- unethical
whats the main exogenous zeitgeber, and whats 1 strength and limitation of research into this?
light
chang et al found ps using light emmiting e-book took longer to sleep than book
those living in arctic regions have normal sleep patterns despite extended day/light period
give research into infradian rhythms. what is 1 strength and 1 limitation of research into infradian rhythms
pheremone samples collected from women then given to others, were brought closer to their cycle
low concurrent validity- other studies didn’t get same results
what a strength and limitation of research into research into ultradian rhythms?
5 different stages of sleep been found using EEG e.g. REM sleep occurs in 5th stage
only done on small sample low pop val
