Sensation: the process of bringing information from the external world into the internal body and brain.
Perception: the process of selecting, organising, and interpreting the raw information that has been taken to the brain by your senses i.e. touch, taste, sight, sound and smell.
Aim:
To investigate whether kittens have to see and move to be able to develop skills such as depth and perception.
Method:
Participants:
- 10 pairs of kittens (20 in total).
- Each pair from a different litter.
- Aged between 8 and 12 weeks.
Design:
Research method: Laboratory experiment
Independent variable: the condition of the kitten: active or passive.
Dependent variable: the perceptual skills and development of the kittens.
‘Kitten carousel’:
- Kitten A could walk around the carousel and explore (neck in a holding device)
- Kitten P was placed in device where paws could not touch the ground
- Kitten P would walk the same directions as Kitten A but without engaging walking.
- 36 inches’ distance between kitten.
Three main tasks:
1.Visually-guided paw placement:
- Held by the body (free paws and legs)
- Moved towards and edge of the table
- A kitten with normal visual experience would extend its paw awaiting the contact.
2.Avoidance of a visual cliff:
- The underside glass was lit from below to make it almost invisible.
- Kitten’s behaviours were recorded.
3. Blinking to an approaching object:
- Each kitten placed in a device like A type carousel.
- Large sheet of plexiglass was placed in front.
- A hand would move towards kitten, stopping just before glass.
Other tests:
- Visual pursuit of a moving object: eye movement of the kitten recorded with moving hand.
- Pupillary reflex to light: a torch was moved across kitten’s eye, change in pupil size was noted.
- Tactual placing response: forelegs hanged freely, front paws on vertical surface.
Procedure:
Ten pairs of groups, split into group X and Y:
- X group (eight pairs) – stayed in complete darkness until A was at the minimum size to be in the carousel. Spent three hours a day on apparatus.
- Y group (two pairs) – three hours’ exposure to the interior of carousel from 2 weeks until 10 weeks old. After, they began a three hour per day exposure of the apparatus. They were kept in lightless cages with mother and litter mates.
- Six paw-placement assessments each day.
- X group – When one kitten could paw place, both kittens would be tested on the visual cliff, tested the next day, P kitten in a lit room for 48 hours
- Y group – only A kitten tested on visual cliff, P kitten exposed to carousel until reaching 126 hours, then tested.
Results:
All A kittens developed:
- Normal visually-guided paw placement response
- Normal blinking response
- Normal level of depth perception
- Normal response to following movements.
P kittens did not develop any perceptual abilities.
After 48 hours in lit room, all kittens had developed a normal set of responses, reactions and perceptions.
Conclusion:
To develop ‘typical’ perceptual development, kittens need to be able to move around by themselves with simultaneous visual feedback.
Strengths:
- High level of control
- Replicable
- Small number of animals
Weaknesses:
- Not generalizable
- Questionable validity
- Lack of ecological validity
- Ethics – darkness and cages, harmful effects on kittens.
CIE A Level Psychology 