The meaning of psychiatric symptoms prior to a diagnosis of genetic frontotemporal dementia is discussed as either being part of a prodrome or being a sign of congenital neuronal vulnerability.

Cheran et al 1 in this journal investigated the nature of lifetime psychiatric symptoms in preclinical MAPT mutation carriers. Compared with their non-carrier relatives as well as the population, they more often had signs of atypical depression, not fulfilling the criteria of major depressive disorder, and they did not have the anxiety and mood disorders that characterised their non-carrier controls. Since atypical depression was a current condition, and no other psychiatric disturbances were reported from their earlier lifespan, some form of emotional blunting and a relative absence of fear might be among the prodromes or early beginning of behavioural variant frontotemporal dementia (bvFTD).

Defining the onset of bvFTD in persons …