Blakemore & Cooper

Question 1

Aim

Answer 1

Limit visual experience of kitten to 1 orientation (horizontal/vertical) to study neurophysiological effects on neurones in visual cortex

Question 2

Research Method

Answer 2

Lab experiment:
+ : high control lvls, standardise, scientific equipment ~ accurate/reliable
- : artificial ~ low ecological validity ; cat ✕ raised like that irl

Question 3

Design & Variables

Answer 3

Independent measures
IV: hori/verti environment
DV: visuomotor (visual perception by brain) for behaviour in illuminated environment + neurophysiological changes
DV 2: whether hori raised kittens could detect verti objects + vice versa

Question 4

Sample

Answer 4

• kittens raised from birth in hori or verti condition
• 1 from each used to look at effect on neurones

Question 5

Procedure

Answer 5

• birth - 2w: kittens in complete dark room
• 2w - 5m: put in illuminated cylinder
• everyday exposed to either only hori or verti 5h
• wore collar to tunnel vision ~ can’t see own body

Question 6

Procedure pt. 2

Answer 6

After 5 months (critical period for visual development):
- removed from dark room & placed in well lit/furnished room
- visual reactions observed + recorded
- after 7.5m, cats anaesthetised + neurophysiology examined

Question 7

Results: Observations

Answer 7

• all cats visually impaired —> no reflexes/startle responses
• behavioural blindness when exposed to opposite orientation (verti can’t detect hori travelling rod)
• BUT after 10h normal vision, cats showed recovery signs eg. Startle response
• some permanent defects, eg. Clumsiness + spatial awareness difficulties

Question 8

Results: Neurophysiological Examinations

Answer 8

• abnormal distribution of neurons
• physical blindness: verti environment cats lacked neurons in hori position + vice versa

Question 9

Conclusions

Answer 9

• supports brain plasticity in cats
• visual experience in early kitten life can modify brains
• brain development environmental (interaction of nature & nurture ~ interactionist)
• but difficult to apply to human brain

Question 10

Type of data

Answer 10

Quantitative & Qualitative:
1) If neurones active or not
2) Behavioural blindness, eg. Chasing rods, reflexes

Question 11

Validity

Answer 11

• high internal: controls ensure only IV (hori/verti) impacts DV (visuomotor)
• ecological validity: unrealistic

Question 12

Reliability

Answer 12

• good internal: replicable ; standardised, eg. Time in darkness
• scientific equipment tested many neurones but only picked up same pattern ~ reliable

Question 13

Sampling bias

Answer 13

• 2 cats in neurophysiological exp ~ extremely small sample BUT assumption all biology in cats are same
• cats can’t represent humans

Question 14

Ethics

Answer 14

• PFH: prevented brain growth, neuro exam = invasive procedure, maternal & visual deprivation BUT used minimum amount + heavily anaesthetised
• Bateson’s decision cube: need to think & compare suffering to importance/usefulness of results

Question 15

Practical Applications

Answer 15

• shows critical period in childhood + it can impact brain development
• insight to visual impairments & how it persists to adulthood if not picked up
• can apply to humans ; mammals & ✕ do on humans