https://padlet.com/11agyare_twums/gyhapqugnngz en-us 2017-03-13 08:09:42 UTC 2025-10-09 15:53:05 UTC hello@padlet.com 11agyare_twums https://padlet.com/11agyare_twums/gyhapqugnngz/wish/159586958 To investigate the effect on kittens' visual development of a restricted visual environment, consisting of either vertical stripes only or horizontal stripes only, in which the animal could move freely.]]> 2017-03-13 08:16:00 UTC https://padlet.com/11agyare_twums/gyhapqugnngz/wish/159586958 11agyare_twums https://padlet.com/11agyare_twums/gyhapqugnngz/wish/159587384 Laboratory-raised kittens that were housed in complete darkness until 2 weeks of age]]> 2017-03-13 08:18:24 UTC https://padlet.com/11agyare_twums/gyhapqugnngz/wish/159587384 11agyare_twums https://padlet.com/11agyare_twums/gyhapqugnngz/wish/159587675 The kittens were kept in the dark unless they were in the visual display apparatus or being tested.
From 2 weeks old to 5 months, each kitten spent on average 5 hours a day in a visual display apparatus]]> 2017-03-13 08:20:00 UTC https://padlet.com/11agyare_twums/gyhapqugnngz/wish/159587675 11agyare_twums https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160118435 Dependent: Effect of rearing the kittens in the 2 conditions.
Independent: Visual display that the kittens were exposed to e.g. horizontal lines or vertical.]]> 2017-03-14 22:04:31 UTC https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160118435 11agyare_twums https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160118755 Vertical lines condition]]> 2017-03-14 22:07:46 UTC https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160118755 11agyare_twums https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160118943 Although the kittens' pupils responded in the normal way to a bright light, in terms of their behaviour they were unlike normal animals regardless of the orientation of the stripes in their rearing environment. They moved around mainly by touch rather than sight, failed to stretch their paws out when they were and brought down towards a table top and showed no startle response when an object was moved quickly towards them. They also appeared to be frightened when they reached the edge of the surface on which they were standing.]]> 2017-03-14 22:09:00 UTC https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160118943 11agyare_twums https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160121304 These deficiencies were overcome within about 10 hours of normal visual experience in the light,  suggesting that they were a problem caused by the absence of an opportunity to link vision with movement.
Some of the kittens' visual defects were permanent. They bumped into stationary objects, followed moving objects clumsily and were poor at judging the distance of objects in order to touch them.
Kittens' startle responses were different depending on the condition they were raised in. When tested for their startle response to a perspex sheet with black stripes, a kitten only responded if it was presented with stripes in the same orientation that they had grown up with.]]> 2017-03-14 22:27:09 UTC https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160121304 11agyare_twums https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160122865 As there was no evidence that areas of the cortex were 'silent', or that areas of cortical cells were missing, this suggests that the changes are not the consequence of degeneration.
The difference between the differently reared kittens suggests that neurons change their preferred orientation according to the stimulation they receive, matching the ability of the brain to respond to the features in its visual input.]]> 2017-03-14 22:38:01 UTC https://padlet.com/11agyare_twums/gyhapqugnngz/wish/160122865