Presentation on theme: "A brief and incomplete history of the study of brain and behaviour."— Presentation transcript:
A brief and incomplete history of the study of brain and behaviour
Greek mythology The hypothesis that the mind, soul or psyche is responsible for behaviour has roots in Greek mythology Psyche was a human who became immortal after completing a number of almost impossible tasks Her psyche became separate from her body
Greek mythology Aristotle (350 BC) alluded to Greek mythology when he suggested that all human intellectual functions were carried out by the mind (psyche) However, Aristotle thought that the mind was located in the heart - he thought the brain was just there to cool the blood
Other Greek thinkers, such as Hippocrates and Galen, did regard the brain to be the seat of intellect and the organ that controls behaviour: Not only our pleasure, our joy and our laughter but also our sorrow, pain, grief and tears rise from the brain, and the brain alone. With it we think and understand, see and hear, and we discriminate between the ugly and the beautiful, between what is pleasant and what is unpleasant and between good and evil (Hippocrates, 400 BC).
Independent bodies and brains Rene Descartes (1596-1650) wrote an influential book on mind and brain He took a philosophical position that both a nonmaterial mind and the material body contribute to behaviour Cartesian dualism
Accidental neuroscience In 1838 Phineas Gage was the foreman of a railway construction gang in New England, USA He was responsible for laying new tracks which involves blasting hard rocks to provide a more level path Gage was considered ‘an efficient and capable man’ by his employers and was well liked by his colleagues One day a rock charge blows up in his face An iron rod entered Gage’s cheek and penetrated the base of his skull, leaving through the top of his head.
Gage survives, is able to walk without assistance, could touch, hear, see (through his right eye) and speak However, some aspects of his personality were changed He became ‘fitful, irreverent, and indulged in the grossest profanity’ This resulted in him losing his job and his friends Gage was no longer Gage
Localisation of function The concept of functional localization began with Franz Gall and the phrenologists in the early 19th century Phrenology (reading personality from bumps on the head) is a discredited science but...
Localisation of function Phrenology did suggest that the brain could be divided up into many separate organs that were responsible for different behavioural faculties Support for the concept of localization came from neurologists who demonstrated that brain lesions had specific effects on behaviour
Localisation of function John Hughlings Jackson, an English neurologist, was one of the first to recognise the localizational view He noted that lesions to the right side of the brain affected visual-spatial processes more than lesions to the left side of the brain
Localisation of function Pierre Paul Broca and Carl Wernike showed how lesions to other parts of the brain (left hemisphere) affected language capability