While the impact of cognition enhancers such as the use of the NMDA agonist d-cycloserine or HDAC inhibitors has been recognized and is investigated as an adjuvant to exposure-based therapies [7, 9, 61, 62] it is surprising that donepezil has not yet been used for managing fear extinction, despite being available for more than two decades for its cognition promoting effects in patients with dementia. The gene discussed is HDAC9; the disease is dementia.