1. Development of Invasive techniques to study the brain: the case of Phineas Gage (Harlow, 1848) – a ‘natural’ lesion

2. Development of Invasive techniques to study the brain: applications from ‘natural’ lesions Case Studies led to the belief that damaged brain areas caused the change in behaviour. Therefore, these areas were targeted in surgery to alter behaviour (e.g. frontal lobotomy).

3. Development of Invasive techniques to study the brain: ‘natural’ lesions & language function Paul Broca used the case study of “Tan” to develop his theory of the localisation of language function.

4. Development of Invasive techniques to study the brain: language function Based on this one case study Broca put forward the claim that speech production is localised in the left frontal lobe of the brain. A view that is still largely held today.