Dr. Stefan Köhler, faculty member in the Department of Psychology and a principal investigator in Western’s Brain and Mind Institute, just received the Premier Research Grant of the Alzheimer Foundation London and Middlesex. The grant offers $100,000 in funding to support a research project that addresses one of the most devastating types of cognitive impairment that can be caused by dementia. A significant number of patients with Alzheimer’s Disease and Lewy Body Dementia develop delusional misidentifications, i.e., the erroneous belief that one of their loved ones, most often their spouse, has changed in identity or has been replaced by an imposter. These delusions place an enormous burden on patient care, given that the ‘imposter’ is typically the primary caregiver. They also have a profoundly adverse impact on the health care system, as their presence is one of the primary reasons for the institutionalization of patients out of the community. In this new line of research, Dr. Köhler and his team aim to examine the role of physiological arousal, which is normally an integral part of recognizing a loved one, in delusional misidentifications of patients with Alzheimer’s disease and related forms of dementia. Their aim is to link changes in arousal to specific memory problems, and to specific brain changes caused by the disease. An improved understanding of these mechanisms promises to provide a foundation for offering guidance to caregivers, and for developing suitable intervention strategies in the future.