split brain research

Question 1

split brain research AO1

Answer 1

→ alleviates epileptic seizures by severing the corpus callosum (main bond between L + R hemispheres)

→ following the surgery the two hemispheres do not exchange info as efficiently as before ∴ reduced no. fits by epileptics who don’t respond to drug treatment.

→ possible side effects: behaviour + perception

Question 2

outline Sperry’s research

Answer 2

CASE STUDY: → tested before + after surgery / observed after surgery
IQ remained unchanged
some issues w/: concentration, orientation + STM but no major issues w/ day to day functioning

LAB: observations + quantitative results (right or wrong answer)
Image/word is projected to pts L. visual field (processed by R hemisphere) or the R. visual field (processed by L. hemisphere). When info is presented to one hemisphere in a split-brain patient, the information is not transferred to the other hemisphere (as the corpus callosum is cut).

• If image presented to R. visual field, pts can draw, answer Q’s + point at it w/ right hand
If image presented to L. visual field, pts can only draw + point at it w/ left hand
• If word is presented to L. visual field, pts can point at related object w/ left hand
• If image presented to L then R visual field, pts unaware they’ve seen image before
• If object put in both their hand then into a bag, pts are able to remove both objects faster than controls
but if one hand finds object of the other, it will drop it – unaware the other hand is seeking it

TS:
Corpus callosum is involved in conveying info between hemispheres
Each hemisphere is independently responsible for processing info on the opposite side of the body / visual field
language lateralised to the L. hemisphere
personality + intelligence not affected by corpus callosum

Question 3

evaluate sperry

Answer 3

+ Highly specialised standardised procedures → blindfolded one eye + only showed image for 1/10s so no time to move eye across image so only 1 hemisphere∴ replicable + reliable

• Some still has part of the corpus callosum intact → disconnection between hemispheres greater in some pts than other

ETHICS:

• informed consent - had major brain surgery ∴ may not be able to give informed consent
• Psych harm - potentially effect self esteem + stress if they realise they are abnormal

IMPS: contributed to understanding on how we processes info +shows Corpus Callosum must only be cut when necessary as it results in functioning impairment

Question 4

split brain research IDA

Answer 4

NOMO vs IDEO
Studies often include very few participants, + often the research takes an idiographic approach. ∴ any conclusions drawn are representative only of those individuals who had a confounding physical disorder that made the procedure necessary. ∴ results cannot be generalised to wider population.