biopsychology lessons 6-9

Question 1

what is the cerebrum

Answer 1

split into two hemispheres which communicate via corpus collusum. has 4 lobes - frontal (speech), temporal (cognitive skills), parietal (sensory info) and occipital (image processing)

Question 2

what is the diencephalon

Answer 2

responsible for sensory function, food intake and sleep cycle. divided into thalamus, hypothalamus and epithalamus.

Question 3

what is the cerebellum

Answer 3

controls motor function and ability to balance. in hindbrain. behind cerebrum and attached to brain stem.

Question 4

what is the brain stem

Answer 4

regulates blood pressure, some reflexes, ‘fight and flight’, breathing and heart rate

Question 5

what is localisation of function

Answer 5

principle that specific functions such as language have specific locations in the brain.

Question 6

what is the somatosensory cortex

Answer 6

receives sensory input from receptors in the skin. located in parietal lobe. amount of somatosensory areas is reflected by the sensitivity

Question 7

what is the motor cortex

Answer 7

generates voluntary movements. controls muscles on opposite side of the body

Question 8

what is the visual centre

Answer 8

converts sensation into perception. located in occipital lobe

Question 9

what is the auditory centre

Answer 9

converts sound waves to nerve impulses which travel to auditory cortex. in temporal lobes.

Question 10

what is the brocas area

Answer 10

named after paul broca who treated patient who could understand spoken language but could not speak or put his thoughts down on writing. he studied 8 similar patients who had similar language problems with lesions in their left frontal hemisphere. he found those with lesions in right frontal hemisphere didn’t have this problem so concluded language centre is in the left frontal hemisphere known as broca’s area

Question 11

what is wernickes area

Answer 11

karl wernicke discovered another area in brain involved with language in posterior left temporal lobe which explains why patient tan could understand but not speak. wernicke proposed language involves separate motor and sensory regions. motor region in broca’s area controls mouth, tongue and vocal cords. sensory region in wernickes area responsible for auditory and visual input

Question 12

evaluation of localisation of function

Answer 12

advantages: brain scan evidence from peterson who used brain scans to show how wernickes area was active in listening task and broca’s area active in reading task. phineas gage study whereby he suffered brain trauma from pole forcing temporal lobe out of his brain and he suffered a change in personality to show that personality is localised to temporal lobe
disadvantages: seen as reductionist as lashley found higher cognitive functions are not localised to specific brain areas. lashley removed areas of rats brains and found no areas were more important in ability to run the maze. simplifying our behaviour to specific brain areas so losing working of the brain as a whole

Question 13

what is brain lateralisation

Answer 13

idea that two halves of the human brain are not exactly alike e.g. left hemisphere is dominant for language and right hemisphere with visual-motor tasks. brain is contra lateral so right hemisphere controls left body side and vica versa

Question 14

evaluation of brain lateralisation

Answer 14

advantages: studying lateralisation helps understand how specific functions are located on specific sides of the brain. roger’s found that in a domestic chicken, brain lateralisation is associated with enhanced ability to perform two tasks simultaneously - finding food and being vigilant for predators. this shows lateralisation enhances brain efficiency in cognitive tasks.
disadvantages: lateralisation changes with age shown by psychologist who found that language became more lateralised to the left hemisphere up to the age of 25 but decreased after that.

Question 15

what is split brain research

Answer 15

used to study brain lateralisation as it shows what functions are dominant for which hemisphere. here patients w epilepsy have their corpus collusum cut which is known as commissurotomized.

Question 16

what is sperry and gazzaniga split brain research

Answer 16

Using the ‘divided field procedure where an image/word is projected to the patient’s left visual field or the right visual field. used three different tests: describe what you see task, a picture was presented to either the left or right visual field and the participant had to simply describe what they saw. tactile test, an object was placed in the patient’s left or right hand and they had to either describe what they felt, or select a similar object from a series of alternate objects. In the drawing task, participants were presented with a picture in either their left or right visual field, and they had to simply draw what they saw. in first one if picture on right then only could describe. same for test 2 in right hand. in test 3 they could draw clearer if in left vf

Question 17

evaluation of split brain research

Answer 17

advantages: through research we can prove hemispheric lateralisation and both hemispheres have different functions e.g. left is for speech and language and right is for visual and spatial.
disadvantages: very few patients and only between 10-15 have been studied so small sample size. sample studies are an extremely varied group as they differ in age and gender.

Question 18

what is plasticity

Answer 18

the ability of the brain to change and adapt synapses, pathways, and structures. can involve the ability of the brain to adapt to damage caused by brain trauma.

Question 19

what is plasticity in the new born brain

Answer 19

first year of a baby’s life is the most fascinating to study as by one year a baby has more neurones and synapses than it will have once fully matured. this is because it is exposed to vast experiences and brain has a lot to learn. example is that if a hemisphere is removed from a new born they will show few or no behavioural or cognitive impairments.

Question 20

what is plasticity as a result of life experience

Answer 20

the natural decline within cognitive functioning with age. boyke found evidence of brain plasticity in 60 yr olds taught how to juggle. they found increase in grey matter in visual cortex. when juggling practice stopped the changes reversed.

Question 21

what is plasticity and meditation

Answer 21

research shown that meditation can change the inner workings of the brain and thus increase plasticity. davidson compared 8 practitioners of Tibetian meditation with 10 student volunteers. both fitted with electrical sensors and asked to meditate for short periods. electrodes picked up greater activation of gamma waves in the monks. students showed a slight increase of gamma wave production.

Question 22

evaluation of plasticity

Answer 22

advantages: research support by maguire who studies taxi drivers in london who had larger grey matter than control group and their frontal hippocampus was larger as they had to remember directions.
disadvantages: may have negative behavioural consequences as the brains adaptation to prolonged drug use leads to poorer cognitive functions in later life and an increase in dementia. most studies are animal studies so can’t be generalised to humans.

Question 23

what are common types of brain trauma

Answer 23

physical trauma - wounds and bullets etc
cerebral haemorrhage - stroke when brain blood vessel bursts
cerebral ischaemia - stroke when brain blood vessel blocked
viral or bacterial infection e.g. meningitis

Question 24

what are mechanisms for recovery in the brain

Answer 24

axonal sprouting - growth of new nerve endings to form new neuronal pathways
denervation super sensitivity - axons become aroused to reach higher levels to compensate for lost axons. can be negative with over sensitivity which can lead to pain
recruitment of homologous areas - on the opposite side of the brain to compensate for damaged side
neuronal unmasking wall - unmasking dormant synapses to open connections to regions of the brain that are not normally active

Question 25

study to support process of functional recovery after brain trauma

Answer 25

Danelli studied italian boy EB who was operated on at 2.5 to remove brain tumour from left hemisphere. after op he lost all linguistic abilities. right handed. underwent intensive rehab and his language abilities improved at 5. continued over three years until he no longer had difficulties. when tested at 17 to controls his right hemisphere compensated for left.

Question 26

evaluation of functional recovery after trauma

Answer 26

advantages: practical application - as it contributed to neuro rehab which uses electrical stimulation of the brain to counter deficits in motor functioning. this shows functional recovery may be natural but may require further intervention.
disadvantages: gender differences - research to suggest women recover better from brain injury than men as their function is not as lateralised. ratcliffe examined 325 patients with brain trauma and found women performed better on tests of attention and working memory but men outperformed in visual analytical skills.