The importance of response times measures in verbal fluency tasks

Abstract

Verbal fluency is a commonly used task in clinical and experimental neuropsychology. It assesses a person’s ability to generate relevant words, according to a given category within a limited amount of time. Phonemic (PF) and semantic (SF) fluency tasks reflect different aspects of language and executive function abilities. In the present study, we investigated first response latency as an additional measure of phonemic, semantic and excluded letter fluency of 44 healthy adults (aged 18 to 39 years old) divided in 2 groups, according to their education level. We investigated potential correlations between response times and education level. Preliminary results from a small sample show that when comparing phonemic, semantic and excluded letter tasks the shortest response time was observed in semantic fluency tasks whereas the excluded letter tasks have the longest (Z = -5.35, p < 0.0005). Education appeared to have a significant negative effect on the mean response times of the participants (for PF U = 137, p = 0.014; for ELF U = 141.5, p = 0.018; for SF t = 2.05, p = 0.046). These results constitute a potential underexamined way to investigate lexical organization and access in verbal fluency. Also, we noted that education contributes not only to overall performance but to response times as well.