I am jointly appointed to the Schizophrenia Division and PET Centre at the Centre for Addiction and Mental Health and the Rotman Research Institute. With my colleagues, we have been investigating how medications used to treat mental illness work, by examining their effects on the chemicals in the brain.

This work has shown that all antipsychotic medications (used in schizophrenia and Alzheimer's disease) work by blocking dopamine receptors in the brain. By finding out the exact level of blockage required to obtain a clinical response in patients with schizophrenia, my work has shown that much lower levels of medication than conventionally used, can lead to clinical response and spares the patients any side-effects. This work is leading to a change in dosing practice in the clinic.

I am now pursuing this approach in patients with Alzheimer's disease who need these drugs to ascertain the appropriate level of medication for them. With colleagues at the Rotman, I am using PET imaging to study regional changes in the frontal and temporal parts of the brain in patients with schizophrenia. The future of this research will involve studying the effects of medications on these brain connections to understand how these connections change with treatment.

This research is supported by grants from the Medical Research Council of Canada, the EJLB, the Canadian Psychiatry Research Foundation and pharmaceutical industry.