1- Biological psych

Biological

-Key Theme 1= regions of the brain

-Key theme 2= brain plasticity

Asssumptions:

• Focus on how nature (not nurture) influences our behaviour
• Involves reducing (reductionism) expls of behaviour to purely bio factors

+= Scientific as often lab expts and measured objectively, deterministic so increases likelihood of being able to treat people with abnormal behaviour.

-= Reductionist as complex behaviours are reduced to bio levle, Focus on nature rather than nurture ignores social experiences, env encounters etc

Sperry (1968)

-Background:

• Corpus Callosum= nerve fibres which connect both hemispheres so they can communicate effectively
• Cerevral corext= outer layer of nerval tissues, plays a key role in memory, attention, perception, awareness, thought, lang and consciousness.
• Epilepsy= abnormal firing of electrical impluses throughout the brain which interrupts normal brain patterns creating a storm. Split brain surgery (cutting c.c.) done as last resort. 
• Left body side= Right hem (e.g. drawing)= Left Visual Field
• Ride body side= Left hem (e.g. language)= RVF

-Aim:

• To study the effects of hemisphere disconnection in split-brain patients and to show each hem has different functions (lateralisation)

-Design:

• Quasi expt- lab env
• IMD
• IV= whether individual had split brain or not
• DV= individuals performance on visual and tactile tasks

-Sample:

• 11 split brain patients (1 female) who'd undergone surgery for epilepsy
• Opportunity sample

-Procedure:

• Sperry used a tachistoscope
• Ps had one eye covered and asked to stare at a point on projector screen
• Info was flashed to either the LVF or the RVF for 1/10th of a second
• Below screen was a gap so ps could be handed objects or reach into a 'grab bag' and touch objects but could not see the objects or their hands
• Visual tasks= recognising pcs, matching pics
• Tactile tasks= identifying objects in hand, dual processing task

-Results:

• Visual:
• if shown object to RVF, p can name, describe and write the name of the object with right hand
• if shown object to LVF, ps cannot name objects but can draw it with their left hand or pick it out from a group of objects with left hand
• if shown to both VF and given pen in their left hand they will name what is in RVF but draw what is in LVF.
• Tactile:
• objects placed in the right hand could be names. Objects placed in the left hand could not be names but could be drawn or picked up with left hand

-Conclusions:

• In split-brain patients, perception in each hemisphere is independent. Info from one VF or hand passes to only one hem and is not available to the other hem
• In SBP, memory in each hem is independent. info from one VF or hand is remembered only by that hem and cannot be accessed by the other.

-Internal v

• high level of control allows to establish a cause-effect
• but could hav epossibly been measuring something different
• P variables? could have tested ps with epliepsy with thei c.c cut and ps before and after having c.c. cut

-Eco v

• patients wouldn't usually have 1/10th sec…