Split brains

Question 1

Sperry (1964)

Answer 1

Monkeys: each hand learned independently, no transfer. Could learn separate tasks.

Question 2

Gazzaniga 1962

Answer 2

Alien hand - pick up newspaper etc

Question 3

Lateralisation of language

Answer 3

Word to JW’s RH = could not name (after full callosotomy). Could only point etc.
Although with only partial callosotomy: could describe, and then LH could guess.

Question 4

Baynes 1998

Answer 4

Left-handed patient, could write with LH

Question 5

Gazzaniga 2000

Answer 5

JW’s RH learned to speak after 13 years

Question 6

Turk 2002

Answer 6

LH = self-recognition

Question 7

Weschler blocks

Answer 7

RH better at visuospatial task

Question 8

Shinohara 2012

Answer 8

Split brain rats better spatial learning and memory if using right HC

Question 9

Ortigue 2009

Answer 9

LH better at MIT, RH better at IIT.

monkey mirror neurons = F5

Question 10

Iacoboni 2001

Answer 10

fMRI found neurons in right STC concerned with imitation of action.

Question 11

Luck 1989

Answer 11

Visual attention can be done in both hemispheres = visual search task faster than controls

Question 12

Holtzman 1984

Answer 12

Two independent orientating systems

Question 13

Arguin 2000

Answer 13

Cued to divide attention to both hemifields at same time = could do this, faster RTs than controls.
Simultaneously direct attention to both HFs.
But differences in type of info used for search: LH higher-level, could use top-down info to guide search, RH couldn’t (Gazzaniga 2015)

Question 14

Lausberg 2003

Answer 14

LH worse at using whole of personal space to make motor gestures. So specific deficits, not just visual attention as a whole.

Question 15

Kingstone & Gazzaniga 1995

Answer 15

Full callosotomy = sky and scraper separate

Question 16

Funnell 2000

Answer 16

Partial callosotomy / spared anterior and splenial fibres = could draw “breakfast”

Question 17

Risse 1989

Answer 17

Spared splenium = could transfer visual info but not sensorimotor.
Opposite if more anterior fibres spared.
= topography / regional specialisation of CC

Question 18

Uddin 2008

Answer 18

MRI revealed intact subcortical connections - may allow transfer of visual info, or become active as result of damaged CC fibres.
But only resting state! Not functional

Question 19

Sergent 1991

Answer 19

Interhemispheric subcortical transfer of simple information allowed size discrimination judgements (but not same/different).

Question 20

Corballis 1994

Answer 20

Only 3 sizes of circle!
Alternative methods used.
Also cross-cueing? e.g. transfer of binary gaze shift info.
Good methodological design and careful interpretation is crucial

Question 21

Gazzaniga 2005

Answer 21

DTI: investigate callosal function specifically.

e.g. rates/routes of interhemispheric recruitment during difficult task.

Question 22

Funnell

Answer 22

LH = false memories.

“Rational” brain e.g. chicken and shovel experiment

Question 23

Miller

Answer 23

Left PFC activated when recalling false memories.

Question 24

Wolford

Answer 24

LH tries to work out sequence / pattern of flashing stimuli, so ends up less accurate. Tries to develop logical strategy.
RH doesn’t try to do this.

Question 25

Gazzaniga 2015 (consciousness)

Answer 25

RH = literal/truthful.
LH = inventive, seeks explanations. Has consciousness that far surpasses RH.
Although brain is a collection of specialised modules, LH integrates information and rationalises it so we have subjective, unified feeling of consciousness.