biopsych

Question 1

human nervous system

Answer 1

the nervous system as a whole - consists of two parts enteral and peripheral nervous system
central nervous system - the center of consciousness - consists of brain and brain stem, an extension of the brain and the link to the the peripheral nervous system
peripheral nervous system - communicates between CNS and sensory/motor neurons
somatic ns - voluntary movements - part of peripheral ns
autonomic ns - involuntary movements - part of peripheral ns - consists of sympathetic NS functions (stimulates functions) - para-sympathetic ns slows functions

Question 2

neurons

Answer 2

action potential - an electrical charge in a neuron
excitatory potential - charge more likely to cause a neuron to fire
inhibititory potential - charge less likely to cause a neuron to fire

salutatory conduction - action potential jumps from node of Ranvier to node of Ranvier rather than traveling directly through the neuron
mylean sheath - a fatty cover of neurons made of Schwan cells, protects against interference
node of Ranvier - small gaps in the myelin sheath

Question 3

synaptic transition

Answer 3

action potential in pre-synaptic neuron causes synaptic vesel to be released -> vesel bonds with wall of axon -> neurotransmitters released into synaptic cleff -> neurotransmitters bond with receivers in post-synaptic neuron -> action potential in post-synaptic neuron

if neurotransmitter does not reach receiver, either dissipates from synaptic cleff or is reuptaken by pre-synaptic neuron and reused in latter action potential.

Question 4

corpus callisum

Answer 4

a dense bundle of neurons connecting the two hemispheres

commisurotomoy - surgical procedure to split the two hemispheres along the corpus callisum

Question 5

localization of brain functions

Answer 5

certain areas of the brain responsible for certain functions - evidenced by brain damage effecting specific functions only

Question 6

hemispheric lateralisation

Answer 6

brain is contra-lateral - right side of brain controls left side body and vise versa

Question 7

motor cortex

Answer 7

responsible for voluntary movement - in frontal lobe along per-centeral gyrus - both hemispheres - different part of cortex responsible for different body parts - logically mapped ie bottom of cortex controls feet top head

Question 8

somatosensory cortex

Answer 8

detects sensory inputs related to touch - located in perennial lobe along the post-centeral gyrus - both hemispheres

Question 9

visual centers

Answer 9

processes visual inputs - located in ocipital lobe - both hemispheres - latralised on visual field not eye
overgaard et al 2008 - case study - p had hemorrhage on left visual cortex - experienced blind sight - suggests secondary processing center in another location

Question 10

auditory centers

Answer 10

processing auditory inputs - located in both temporal lobes

mayer at al 2010 - auditory cortex processes imaginary sounds as well as real ones

Question 11

language center - production

Answer 11

brocas area - produces all language - in left frontal lobe below motor cortex
tan - case study - P had damage to left frontal lobe, only able to say tan but could process language properly - 8 others with similar symptoms and damage - no effect on speech if damage done to same area of right hemisphere

Question 12

language center - processing

Answer 12

wernicks area - processes language - invloved in understanding - located in left temporal lobe
case study - P with legion could speak and hear but could not understand it

Question 13

AO3 of language center studies

Answer 13

• function localisation not agreed on - amount of damage more important to effect on functions
• unknown how areas communicate
• MRI’s revealed extra damage in Brocas p’s not just in brocas area
• peterson et al areas had multiple functions
  + damage to certain areas produces consistent symptoms
  + Individual diffrences in brain topology explains differences in damage locations

Question 14

split brain research

Answer 14

spery 1968 - 11 p’s with commissurotomy to treat epilepsy - found left field of view processed in right hemisphere and vice versa as objects in left field of view not able to be vocalized but could be written due to no language centers in right hemisphere
gazzinga 1983 - faces more likely to be recognized in left field of view (right hemisphere)

Ao3
- spery small sample size
- no non epileptic control group
\+ supports brain localization
\+ suggests functions of each hemisphere
\+ empirical results - variables operationalised
- patients varied in level of disconnect
- over simplification
- plasticity function area may not be so rigid

Question 15

brain plasticity

Answer 15

the ability to replace lost functions through physical damage
increased brain stimulation - surrounding areas increase in activity to compensate for loss
axon sprouting - undamaged neuron sprout an extra axon to give input to neurons which lost input through damage - only if surrounding neuron and damaged neuron have similar function
denvenation super sensitivity - surrounding neurons become more sensitive to compensate for lost functionality - can result in chronic pain

Question 16

functional recovery

Answer 16

limiting coping mechanisms to ensure that the function recovers correctly

Question 17

neuron unmasking

Answer 17

unstimulated neurons become stimulated to compensated for damaged neuron

Question 18

factors of recovery

Answer 18

persaverance - continuing to used damaged function rather than coping mechanisms would gradually increase functionality
physical stress and toxic exposure - weakened functions required more energy to use if focused energy on other thing recover took longer
age - brain deteriates with age - marquez de la plata et al 2008 - older P = slower and less recovery - 40+ yo regained less functionality
gender - ratcliff et al 2007 - 325 P 16-45 yo - woman recovered better, but no base line from before trauma
education - schindler et al 2014 - higher education resulted in better recovery - 39% of grads recovered, 10% of dropouts recovered

Question 19

functional Magnetic Renaissance Imaging

Answer 19

measures brain activity by measuring blood flow during an activity - increased blood flow to an area indicates its use during a function - uses radio waves for background image, magnets for concentration
AO3
\+ not reliant on radio waves
\+ high resolution and very accurate
- expensive
- P must be still for extended period of time
- indirect - measures blood not neurons
- time delay between neurons an blood

Question 20

Electroencephologram

Answer 20

uses electrodes to detect activity - shows general areas of activity
AO3
+ useful for a wide range of physiological and psychological issues like epilepsy and sleep patterns
+ high temporal vale
- general groups not specific neurons - individual neurons too weak

Question 21

event related potential

Answer 21

takes EEG results and uses statistical averaging to disregard extraneous activity - isolates specific area
AO3
+ more specific than EEG
+ maintains temporal value
+ costa et al 2003 - ERP’s more accurate than self report methods
- not standardized
- hard to differentiate between useful and extraneous activity

Question 22

post mortom/autopsy

Answer 22

physically examines brain after death - establishes exact area of damage
AO3
+ more dtailed
+ no pain or discomfort
- difficult to determin cause and effect - no input or output
- no opertunity for informed consent
- brain breaks down quickly after death
- additional damage may be done between start of symptoms and death