Grant: Doctoral Award - Frederick Banting and Charles Best Canada Graduate Scholarships

Many survivors of brain injury have residual deficits, which can have devastating effects. One area of research has focused on patients' inability to recall personal memories, known as "autobiographical memory," and imagining the mental experiences of other people, known as "theory of mind." Neuroimaging studies used to visualize activity in the healthy brain suggest that these two abilities activate a common brain network. However, a study of patients with impaired autobiographical memory but intact theory of mind suggests that these abilities are separable. An important question lies in whether damage to one of the regions in the common network will impair both abilities. This study will examine how the network might be disrupted or reorganize itself after selective damage. The innovative approach of combining neuroimaging and patients within the same study will allow us to explore these questions. Twenty patients with lesions to the frontal lobes, 20 patients with lesions to the temporal lobes, and 20 healthy participants will be included in this study. We will use a 'family photo' test to examine the relationship between autobiographical memory and theory of mind. Participants' brain activity will be recorded as they view personal photos of themselves ('memory' condition) and of strangers ('theory of mind' condition) engaging in distinct events. Participants will recollect the events depicted in the 'memory' photos and generate a possible event for the 'theory of mind' photos, while inferring what the people in each photo were thinking and feeling at the time. Given that frontal- and temporal-lobe regions have been implicated in recalling personal memories and theory of mind, this project will allow us to better understand the consequences of direct damage to these brain structures. Furthermore, this knowledge will help in predicting behavioural outcomes in patients with brain injury and in guiding compensatory rehabilitation strategies.