Depression is a common psychiatric disorder, and approximately 30% patients with depression do not respond effectively to standard antidepressant medication; this condition is termed treatment resistant depression (TRD) and its neurobiological mechanism remains unclear. Neuroimaging techniques can non-invasively explore changes in brain structure, function and metabolism. These techniques have been applied in neurobiological research of TRD and revealed critical abnormalities in brain structure, function and metabolism in fronto-limbic system. In this paper, we reviewed the latest progress in neuroimaging researches on TRD, providing new insight and imaging evidence for further neurobiological studies of TRD.
