Week 1 - Introduction

Cognition

The process of knowing, what arises from awareness, perception, and reasoning

Neuroscience

The study of how the nervous system is organised and functions

Cognitive neuroscience

The study of how the structure and function of the brain influences how we think, feel, and behave - how the brain produces the mind

Monism

There is no separation between the mind and brain. The idea that the brain → mind is based on this

Dualism

Proposed by Descartes, the mind and brain are separate, the mind comes from elsewhere and is not the result of the brain, opposes monism

When scientists began asking how the brain produces the mind

19th century via the scientific methods

The big question early scientists were asking

Is the mind produced by the collective action of the brain or specific brain regions

Phrenology

Gall thought the brain was organised into 35+ functions and the more you used that function, the more it would grow and cause bumps on the skull, earliest investigation of localisation of function

Flourens

Used ablation to remove brain regions in animals and didn’t find specific brain regions linked to cognitive abilities, found some regions (e.g. cerebellum) were linked to basic functions (e.g. balance)

Aggregate field theory

• Proposed by Flourens - the brain functions as a unified whole rather than through localised regions

• Killed the idea of localisation of function for a really long time

Return of the locationist view

• Hughlings Jackson proposed a topographic organisation to the cerebral cortex through work with epilepsy patients

• First scientist to realise that cognitive functions can be localised to certain parts of the brain and that different functional regions take part in any given behaviour

Broca

• Extended the concept of experimental ablation to stroke patients

• Patient could understand language but not speak (could only say “tan”)

• Found that left frontal lobe was responsible for articulate speech

Broca’s area

Region of the left hemisphere involved in speaking ability

Wernicke

Patient could speak but made little sense and did not understand spoken or written language

Wernicke’s area

Region in left hemisphere (temporal lobe) responsible for language comprehension and processing

Frtisch and Hitzig

• First to use electrical stimulation to understand function

• Stimulated brain surfaces of frog and dog brains

• Found this caused specific muscular contractions, supporting the localisation of function

Brodmann

Used tissue stains and cellular organisation (cytoarchitectonics) to document 52 brain regions called Brodmann’s areas

Golgi

Developed a staining technique (silver chromate, “the black reaction”) that allowed visualisation of individual neurons (dendrites, soma, axon)

Syncytium

That the cells in the brain form a network/continuous mass of tissue, Golgi believed in this

Cajal

• Discovered the direction of travel of nerve impulses in brain and spinal cord, info travels one way from the dendrites to axons

• Postulated that neurons are discrete entities

• Some call the father of modern neuroscience

Purkinje

Described the first nerve cell in the nervous system in 1937

von Helmholtz

Found electrical current in cell was not a by-product of cellular activity but the medium carrying info along the axon

Sherrington

Coined the term “synapse”

Rationalism

Truth through reason alone (reliance on reason), grew out of the enlightenment period

Empiricism

All knowledge comes from direct sensory experience (reliance on data that is observable)

Associationism

• Direct sensory experiences produce building blocks of psychological experience, which interact or become associated with one another in ways that produce human cognition

• Ebbinghaus was the first to study this

• One of the earliest psychological foundations

Behaviourism

Focus on what is observable

Ebbinghaus

Thought complex mental processes could be studied

Watson

Though a behaviourist, rejected Ebbinghaus’ idea of mental processes, proposed psychology could be objective only if based on observable behaviours

Thorndike

Described that a response followed by a reward would be stamped into the organism as a habitual response

The cognitive revolution

Miller (limits of short term memory 7 ±2), Chomsky (language models, somewhat obliterated behaviourism), Donders (development of reaction times)

Donders

Proposed that reaction times could infer differences in cognitive processing

Milner

• Studied effects of injury and surgery on brain

• Patients kept complaining about memory loss

• Provided first anatomical and physiological proof of multiple memory systems

Goldman-Rakic

Produced the first descriptions of prefrontal cortical circuits and how they relate to working memory

Penfield

Invented the Montreal procedure for treating epilepsy - surgically destroying neurons that produced seizures, determined which cells to destroy by stimulating brain parts with electrical probes, created maps of sensory and motor cortices

Hebb

“Cells that fire together, wire together”, proposed that neurons can combine into a single processing unit and the connection patterns of these units makes up ever-changing algorithms that determine the brain’s response to stimuli