Biological - (CLASSIC) - brain plasticity - BLAKEMORE & COOPER

Question 1

the thalamus of a cat is part of the brain made up of a number of structures such as the…

Answer 1

hypothalamus, epithalamus

Question 2

define neuroplasticity in cats

Answer 2

the brain changes with experience and studies have shown that changes in the visual stimuli that cats receive is correlated with changes with changes in RNA structures

Question 3

what is flexibility of cerebral encoding from visual information

Answer 3

the brain will process the different information it sees in different ways leading to experience specific brain adaptations. From this we can conclude that if two cats see very different things their brains will develop in different ways

Question 4

explain what happens when a normal kitten sees something upright, laid down or on a slant

Answer 4

the brain creates a neural pathway to represent that angle of orientation so that it will recognize and respond appropriately to that stimulus if it sees it again

Question 5

explain what would happen if a cat has only seen vertical lines

Answer 5

it will lack a system of neurons for horizontal lines in their brain and will be unable to see them

Question 6

explain the difference between monocular vision and binocular vision

Answer 6

monocular vision is vison in which each eye is used separately whereas binocular vision is vision in which both eyes are used together

Question 7

which cortex do the neurons from the eyes connect to

Answer 7

visual

Question 8

what happens to the neurons if one of the kittens eyes is covered

Answer 8

cortical cells loose input from that eye between 3 weeks to 6 months

Question 9

what has research shown about the cells/neurons in the visual cortex

Answer 9

each cell prefers a certain orientation - some cells prefer to detect horizontal/vertical

Question 10

what behaviors does the kitten display if it has been reared only seeing horizontal lines

Answer 10

no visual placing reaction
np startle reaction
does not follow moving objects unless makes a noise

Question 11

what can be concluded from the research

Answer 11

visual aspects are acquired rather than innate

Question 12

why could a kitten reared in a horizontal orientation not see a table top

Answer 12

early visual experiences - only been exposed to horizontal lines - developed neurons that prefer horizontal orientations so can only detect horizontal orientations

Question 13

aim of the study

Answer 13

investigate kittens’ visual development of a restricted visual environment consisting of either vertical stripes only or horizontal stripes only

Question 14

research method

Answer 14

lab experiment which used independent measures design

Question 15

DVS

Answer 15

-their visuomotor behavior once they were placed in an illuminated environment - whether the horizontal raised kittens could detect vertically aligned objects
-neuronal activity in the brain to investigate plasticity

Question 16

sample

Answer 16

kittens randomly allocated to one of two conditions (horizontal or vertical)
two of the kittens (one reared in a horizontal and one reared ina vertical environment) were used to study petrophysical effects - anesthetized and used their brain

Question 17

describe the procedure

Answer 17

the kittens were housed from birth in a completely dark room
from age of 2 weeks put into apparatus for average of 5 hours per day
it could not see its body as it wore a wide black collar that restricted its visual field to a width of about 130 degrees
routine was stopped when the kittens were 5 months old which was considered well beyond the critical period in which total visual deprivation causes psychological defects
kittens were taken for several hours each week from their dark cages to a small well lit room furnished with tables and chairs
their visual reactions were observed and recorded
at 7.5 months two of the kittens were anaesthetized so their neurophysiology could be examined

Question 18

describe the apparatus the kittens were put in

Answer 18

kittens stood on a clear glass platform inside a tall cylinder which the entire inner surface was covered with high contrast black and white stripes either vertical or horizontal
there were no corners to its environment and no edges

Question 19

behavioral observations

Answer 19

-pupil responses were normal but showed no visual placing when brought up to a table top
-no startle responses when an object was thrust towards them
-guided themselves mainly by touch and not vision
-showed behavioural blindness - kittens raised in horizontal environment could not detect vertically aligned objects

Question 20

permanent defects shown by cats

Answer 20

-always followed moving objects with very clumsy jerky head movements
-often tried to touch things moving on the other side of the room well beyond their reach

Question 21

neurophysiological examination results

Answer 21

horizontal plane recognition cells did not fire off in the kitten from the vertical environment and vertical plane cells did not fire off in the kitten from the horizontal environment so there was distinct orientation selectively showing the kittens suffered from physical blindness
about 75% of cells in both cats were clearly binocular and in almost every way the responses were like that of a normal kitten showing little neurophysical response to the rearing environments
a kitten raised in a vertical environment had no neurons within 20 degrees of a horizontal orientation

Question 22

conclusions

Answer 22

kittens showed behavioral blindness in that the kittens raised in the horizontal environment could not detect vertically aligned objects and vice versa concluding that visual experiences in the early life of kittens can modify their brains and have profound perceptual consequences
the kitten raised in a vertical environment had no neurons within 20 degrees of a horizontal orientation concluding that a kittens nervous system adapts to match what it visually experiences

Question 23

strength of research method

Answer 23

high levels of control over extraneous variables e.g kittens exposure to visual apparatus was precisely timed and they were kept in a dark room otherwise so we can be confident the IV whether kittens raised in vertical or horizontal orientation was effecting the DV behavior and neuronal activity

Question 24

strength of quantitative data collected

Answer 24

easily compared - can easily compare horizontally and vertically reared cats on the number of neurons with optimal orientation degrees of the opposite orientation to lines in their rearing environment - can see that the rearing environment has affected the neurons in the kittens visual cortex providing evidence for brain plasticity

Question 25

weakness quantitative data

Answer 25

lack of detail and insight - no information about the behavioral consequences of being reared in the vertical or horizontal environment - limited understanding/conclusions about the consequences of the reported changes to neurons in the visual cortex

Question 26

strength qualitative data

Answer 26

insight and detail - kittens had no startle response, always followed moving objects with very clumsy jerky head movements - good because we get an understanding of the consequences of the reported changes to neurons in the visual cortex

Question 27

weaknessqualitative data

Answer 27

cannot be easily compared - can’t easily compare behavioral consequences of being raised in a vertical and a horizontal rearing environment - difficult to determine if different rearing environment has caused differences in the kittens development

Question 28

weakness of sample

Answer 28

small sample - only 2 kittens reported on the neurological findings - the findings about the effects of the environment on the activity of the neurons may not generalize to all cats

Question 29

strength of concurrent validity

Answer 29

both behavioral and neurological measures were taken to measure the effect of the restricted visual rearing environment. Both showed evidence that the kittens raised in the horizontal visual environment did not see in the vertical orientation and the opposite was true of the kittens raised in the vertical environment. The fact that both showed such evidence suggests that both measures i.e the behavioral and neurological measures were valid measures of the effect of the restricted visual environments

Question 30

comment on how the study is reliable

Answer 30

standardized controlled procedure so could be replicated - special apparatus i.e clear glass platform inside a tall cylinder the entire surface of which was covered with high contrast black and white stripes, vertical or horizontal, cat in their for an average of 5 hours a day and in the dark otherwise

Question 31

mment on how the study is not reliable

Answer 31

only 2 kittens provided the results of the physiological part of the study so too few to be confident that the findings about the effect of rearing environment on the development of the visual cortex are externally reliable

Question 32

comment on how the study is ethical

Answer 32

only 2 kittens used and no fewer could possibly have been used as two needed to raise in a vertical and another in a horizontal environment

Question 33

comment how this study is not ethical

Answer 33

kittens would have suffered some pain and distress from the invasive procedure and distress from being separated from their mothers while in the visual apparatus and being tested although it was noted that the kittens did not appear upset by the monotony of their surroundings so this may have not been the case

Question 34

comment on the practical applications

Answer 34

helps us understand the effects of visual deprivation in growing children e.g if visual impairments are not detected and corrected early enough these findings potentially suggest that potentially long term damage may be done to the cortical areas associated with the particular types of stimuli that cannot be seen by the child