OTHER MINDS IN THE BRAIN - A FUNCTIONAL IMAGING STUDY OF THEORY OF MIND IN STORY COMPREHENSION

The ability of normal children and adults to attribute independent men tal states to self and others in order to explain and predict behaviou r (''theory of mind'') has been a focus of much recent research. Autis m is a biologically based disorder which appears to be characterised b y a specific impairment in this ''mentalising'' process. The present p aper reports a functional neuroimaging study with positron emission to mography in which we studied brain activity in normal volunteers while they performed story comprehension tasks necessitating the attributio n of mental states. The resultant brain activity was compared with tha t measured in two control tasks: ''physical'' stories which did not re quire this mental attribution, and passages of unlinked sentences. Bot h story conditions, when compared to the unlinked sentences, showed si gnificantly increased regional cerebral blood flow in the following re gions: the temporal poles bilaterally, the left superior temporal gyru s and the posterior cingulate cortex. Comparison of the ''theory of mi nd'' stories with ''physical'' stories revealed a specific pattern of activation associated with mental state attribution: it was only this task which produced activation in the medial frontal gyrus on the left (Brodmann's area 8). This comparison also showed significant activati on in the posterior cingulate cortex. These surprisingly clear-cut fin dings are discussed in relation to previous studies of brain activatio n during story comprehension. The localisation of brain regions involv ed in normal attribution of mental states and contextual problem solvi ng is feasible and may have implications for the neural basis of autis m.