The proposed research investigates the nature of communication problems in right hemisphere (RHD) and prefrontal damaged (PFD) patients. These patient groups are known to exhibit difficulty with discourse. Successful communication rests on understanding others' perspectives, beliefs and motivations. the investigators' previous work suggests that other RHD patients have problems in determining what one's person believes about another person's beliefs (theory of mind deficits) and tend to avoid internal trait accounts for behavior in favor of external explanations (attribution deficits). The proposed research will (1) examine patients' theory of mind and attribution deficits on more complex tasks than we have used so far, and (2) determine whether the deficit is specific or part of a broader deficit in either central coherence and/or executive function. Central coherence deficits could lead to mentalizing/internalizing deficits because theory of mind and attribution tasks require that one make inferences about others on the basis of disparate pieces of information. Executive function deficits could lead to difficulties on such tasks because the tasks require responding on the basis of inferred or hypothetical states rather than concrete, observable reality. Central coherence will be tested by means of a reading comprehension test; executive function by means of the Tower of Hanoi task. In addition, control tasks will be used to compare patients' abilities to make mentalistic inferences with their abilities to make physical ones. If problems in mentalizing/internalizing are specific, patients should perform better on control tasks. If they are general, patients should perform poorly on both test and control tasks. The proposed framework will help clarify the nature of the social and communication deficits known to affect RHD and PFD patients.
