Breathing and verbal fluency performance: An approach across the adult lifespan

Understanding the determinants of age differences in complex cognitive abilities such as verbal fluency (VF) is an important challenge to solve in aging research. Among the mechanisms rarely addressed in this field of study are physiological functions underlying oral language such as breathing, which is foundational to speech production. To address this gap, we conducted an aerodynamic assessment during performance of semantic and phonemic VF tasks in three healthy age groups including adolescents (n = 40), young adults (n = 30) and older adults (n = 30). A pneumotachograph was used during word generation in both VF tasks to acquire respiratory measurements and oral responses. One minute was allotted for each VF trial. Both respiratory and auditory data of oral responses were analyzed by four 15-s intervals with repeated measures ANOVAs. Results showed that use of airflow differentiated VF tasks in the same way across groups. Conversely, respiratory cycles differed significantly between groups and verbal tasks. Older adults demonstrated higher respiratory rates and low VF ability, especially in semantic VF, during the first 15 s of VF tasks as compared to young adults, who had the lowest respiratory rates and the highest VF performance. Adolescents did not differ significantly from the other groups. Finally, accuracy of responses in VF tasks was significantly correlated to respiratory measures only in the younger groups, while a lack of correlations was observed in the older group. Factors underlying the above findings are revised, including the possibility of increments in arousal in older adults. The present findings are suggestive of greater involvement of autonomic regulation at certain periods of the lifespan via respiration that might contribute to age differences in VF performance.