Date of Award
Doctor of Philosophy
Elizabeth L Stegemoller
Older adults experience a decline in inhibitory control, specifically cognitive and motor inhibition. These declines have been associated with poorer performance in instrumental activities of daily living. However, studies have revealed that older musicians have behavioral and neurophysiological enhancements in various cognitive and motor domains as compared to non-musicians. This suggests that music training may delay the decline in cognitive and motor inhibition with aging. Yet, cognitive and motor inhibition has not been studied across the lifespan in musicians and non-musicians. Thus, the aim of this study was to investigate the behavioral and neurophysiological differences in cognitive and motor inhibition in aging musicians and non-musicians.
Twenty healthy young adult musicians and non-musicians (between ages 18 and 35) and twenty healthy older adult musicians and non-musicians (between ages 65 and 80) were recruited for the study. To measure cognitive inhibition, the Stroop task was performed while electroencephalography (specifically P300 waveform) was recorded. Participants were asked to name the color of a word presented in either red, green, yellow, or blue. Three conditions were presented randomly: neutral (infrequent words sol, helot, eft, and abjure presented in different colors), congruent (color of word matches the word), and incongruent (color of the word does not match the word itself). Accuracy and response time were recorded using E-Prime 2.0 (Psychology Software Tools, Pittsburgh, PA). P300 amplitude and latency were recorded, processed, and analyzed using ActiveTwo Bio Semi system (BioSemi, Amsterdam, NL) and MATLAB. To measure motor inhibition, participants were asked to perform an index finger flexion-extension movement (i.e., finger tap) in sync with an auditory tone (i.e., synchronized) and between auditory tones (i.e., syncopated) presented at 1 Hz. The forearm, wrist, thumb, and fingers 2-4 were supported with a brace maintaining the forearm in a pronated position with the elbow flexed at 90 degrees. The index finger remained unconstrained to allow for full range of motion without touching a surface. Transcranial magnetic stimulation (Magstim Model 200, Magstim, Whiland, Carmarthenshire) single-pulse and short interval cortical inhibition were performed at rest and between synchronized and syncopated finger taps. Finger tap accuracy was recorded using a goniometer. Motor evoked potential amplitude was recorded from electromyography (Delsys, Boston, MA, USA) and analyzed in The Motion Monitor (Chicago, IL, USA).
Results revealed musicians overall display enhanced cognitive inhibition, motor inhibition, and processing speed. We observed that musicians displayed a decrease in incongruent response time and earlier P300 latencies and greater P300 amplitudes. This indicates better cognitive inhibition in musicians. We observed that music practice, decreased short interval cortical inhibition motor evoked potential, and decreased inhibition percent predict better syncopation timing during syncopation. This indicates better motor inhibition in musicians. Furthermore, exploratory analyses revealed that musicians contain more refined rather than overlapping inhibitory pathways. In closing, results suggest that engaging in music practice and music training throughout life may maintain or enhance inhibitory control and associated brain regions. Since decrements in inhibitory control are associated with lower quality of life, these results reveal that playing music may improve quality of life for older adults and serve as a guide to future design of music training/practice interventions in older adults.
Izbicki, Patricia, "The behavioral and neurophysiological effects of music training on cognitive and motor inhibition in aging adults" (2020). Graduate Theses and Dissertations. 17898.