A Brief History of Cognitive Neuroscience

Question 1

What is phrenology?

Answer 1

• The idea that a person’s functions/traits are highly localised to a particular brain area
• Proposed that activation of brain areas make them expand, which results in changes of skull shape

Question 2

What has phrenology taught us?

Answer 2

• Led to the study conducted by Marie-Jean-Pierre on pigeons which showed us the alternative perspective of an aggregate field’s theory

Question 3

Where was phrenology right?

Answer 3

• Phrenology introduced the idea that different mental functions could be localized to specific regions of the brain
• Phrenology was an early attempt at creating a map of mental functions in the brain

Question 4

Where was phrenology wrong?

Answer 4

• Gall observed correlations and sought only to confirm, not disprove, them

Question 5

What is the difference between the localizationist’s and the aggregate field’s point of view?

Answer 5

Localizationist’s POV: Specific behaviours can be localised to certain brain areas

Aggregate field’s POV: The interaction of all brain areas is required to mediate a behaviour

Question 6

What is the evidence in favour of the localizationist’s point of view? (3)

Answer 6

1. John Hughlings Jackson monitored epilepsy patients and realised that seizures often resulted in ‘ordered’ jerks of the muscles
   - This led to the idea of a topographic organisation of muscle representation in the cortex
2. Broca and Wernicke areas
   - Specific brain lesions were associated to specific deficits in language production and comprehension
   - Broca: Speech production
   - Wernicke: Language comprehension
3. Broadman
   - Used novel cell staining techniques to subdivide the human cortex into different cytoarchitectonic areas (cytoarchitectonic = how cells differ between brain regions)
   - Divided on the basis of cell structure and arrangement

Question 7

What is the evidence in favour of the aggregate field’s point of view? (1)

Answer 7

• Marie-Jean-Pierre Flourens lesioned various parts of the pigeon brain
• Removal of cerebral hemisphere removed perception, motor ability and judgment
• However, there were also specific behavioural deficits not affected by a specific lesions
• Concluded that behavioural abilities are mediated by interactions of areas from the entire brain

Question 8

What is the neuron doctrine?

Answer 8

The argument that neurons are part of one large syncytium (i.e. neurons are not separate units)

Question 9

Who supported the neuron doctrine?

Answer 9

• In support: Freud
• Against: Golgi and Cajal
  *Endorsed the fundamental concept that the nervous system is made up of discrete individual cells
  *Received a Nobel Prize award for their work

Question 10

What is behaviourism?

Answer 10

• The argument that learning and conditioning are the main/sole determinants of all behaviour
• A school of thought that evolved from empiricism
  -Thorndike and Watson (developed); Skinner (crystallized)

Question 11

What are its limitations?

Answer 11

• In its extreme form, behaviourism believes that internal states do not exist (and living creatures can be ‘programmed’ by appropriate conditioning)
• Inability to explain language or provide insights into perception, emotion, memory, decision-making

Question 12

What is empiricism?

Answer 12

• All knowledge is derived from sensory experience
• Simple ideas interact and can become associated to form complex knowledge systems or behaviours (associations; associationists)

Question 13

What do associationists believe?

Answer 13

• Learning is key to all behaviour
• Overemphasizing ‘nurture’ with sometimes a complete disregard to ‘nature’

Question 14

What has behaviourism taught us?

Answer 14

Insights into the nature and mechanism of learning processes