Grant: Operating Grant

There is little understanding of the brain regions and networks that support awareness of past and current mental states belonging to oneself and to other people. While brain damage may cause obvious deficits in cognitive abilities such as attention and language, it may also lead to subtler, yet equally devastating deficits, such as the inability to decipher other people's thoughts and feelings, what is known as 'theory of mind.' Our ability to cooperate, deceive, and empathize rests on theory of mind, which allows us to recognize in others a set of beliefs that might not correspond to our own beliefs. The loss of this ability can thus have enormous social consequences for patients and their families. The proposed research uses an innovative approach of combining the examination of theory of mind impairment following brain lesions, with functional magnetic resonance imaging (fMRI), a technique that allows visualization of on-line brain activity as participants perform various tasks. A first set of studies examines how damage to discrete regions of the frontal and temporal lobes can impair the ability to represent mental states on a wide range of tests known to be sensitive to theory of mind impairment. The relationship between theory of mind and remembering one's own past mental states during autobiographical memory, which draws on similar brain regions and processes, will then be investigated using a novel real-world 'family photos' test. Patients will be scanned with fMRI to explore differences in brain regions recruited as they recollect their own mental states while viewing personal photos of past experiences, and as they infer other people's current experiences when viewing strangers' photos. These studies will also help to reveal how damage to a region can affect the remaining network of regions. These findings could lead to new diagnostic tools and rehabilitation techniques to help individuals with brain injury lead emotionally and socially fulfilling lives.