Biopsych - Localisation & Lateralisation Flashcards
localisation, lobes & areas, lateralisation, hemispheres, cases/studies & supports/refutes
Localisation
Functions occur in certain locations of the brain
Frontal lobe
Area of brain related to decision making, social skills and thinking (+personality)
Motor cortex
- Located in frontal lobe
- Regulates movement (opposite sides [left field = right side, right field = left side])
Broca’s area
- Left hemisphere of frontal lobe
- Responsible for speech PRODUCTION (damage leads to Broca’s aphasia)
Temporal lobe
Area of cerebral cortex related to auditory processing
Auditory cortex
- Located in temporal lobe
- Analyses speech based information
Wernicke’s area
- Located in left temporal lobe
- Responsible for language COMPREHENSION (damage leads to Wernicke’s aphasia)
Occipital lobe
Area of cerebral cortex related to visual processing such as colour or depth perception
Visual cortex
- Located in occipital lobe
- Receives/processes visual info
Parietal lobe
Area of cerebral cortex vital for sensory perception and integration of senses
Somatosensory cortex
- Located in parietal lobe
- Processes sensory information from the skin
+ Research in localisation
+ Broca & Tan - analysis of his brain post-mortem supports idea that the damage to Broca’s area impacted speech production
+ Buckner & Petersen - review of long-term memory studies & utilising brain scans support ideas of memories residing in different areas & areas being active during tasks
- Research in localisation
- Lashley - removed brains 10-50% in rats to see how it impacts them refutes localisation as no area was deemed more important for completing the maze
Lateralisation
Each hemisphere has a certain function
Left hemisphere
Language/logical/analytics
Right hemisphere
Emotion/creativity
Contralateral
Hemisphere controls opposite side of body (LH -> right [e.g. motor])
Ipsilateral
Hemisphere controls same side of body (LH -> left)
Special case: vision
Both eyes have a left & right field of vision -> RVF = LH, LVF = RH
Split-brain research
Severed connection between the LH & RH -> researchers look at how the hemispheres function w/o communication (surgery is done to reduce epilepsy)
Study: Sperry
- Aim: how 2 separated hemispheres deal with vision/speech related things
+ Sample: 11 people who had the operation - Method: Images projected to either LVF and/or RVF in 1/10th a second [they had 1 eye covered]
Sperry’s findings (LVF)
Could not name what they had seen [no language in RH], could draw what they had seen with their left hand [controlled by RH], pinup girl scenario: had emotional reaction [blushing] but could not describe what had been seen
Sperry’s findings (RVF)
Able to describe in speech & writing with right hand
Conclusion of Sperry
LH = verbal
RH = silent but emotional
+ Research on lateralisation
+ Kim Peek lacking corpus callosum supports as he could work independently and perform 2 tasks at once
+ Michael Gazzaniga split brain patients supports as they can perform better on certain logical tasks than connected patients
- Research on lateralisation
- Nielsen et al analysed brain scans and contradicts lateralisation as there was no evidence of a more dominant side
- Holland et al contradicts as functions can be taken over by the opposite hemisphere after damage
