Verb production during action naming in semantic dementia

Research highlights ► We addressed how does semantic verb knowledge disappear in semantic dementia (SD) using video clips of object-related actions. ► This semantic impairment followed a hierarchical pattern according to which the more specific verbs vanished away first. ► Further, abnormal responses in patients consisted of verbs that were still semantically related to the expected verbs produced by control subjects. ► Although their semantic knowledge became progressively impoverished, SD patients did not violate semantic coherence between the stimulus and the response they made.