Physiological Evaluation of Music Effect for the Mental Workload

Studies of mental stress have become the more important topics recently. Various studies have been conducted on physiological effects of music, while the effects of music under stress condition is not revealed in detail. The purpose of this study is to investigate the effects of music on participants’ subjective and physiological response by mental workload. First, eight participants (mean age; 25.6) were requested to perform the Uchida-Kraepelin test, which was given as a simple mental calculation task, for 30 minutes. After that, participants were exposed to music (“Bolero”, M.Ravel) for 13 minutes, while they were exposed to noise or just stayed in silence as a control. State-Trait Anxiety Inventory (STAI), salivary Immunoglobulin A (sIgA) , auditory event-related potentials (ERPs) and heart rate (HR) were assessed through the experiment. Results: 1) Before and after the calculation task: Saliva secretion rate and salivary IgA levels significantly decreased and increased (p<.01). P300 amplitude of auditory ERPs significantly decreased (p<.05). HR significantly increased (p<.01) during the calculation task comparing with before and after the calculation task. 2) After music (“Bolero”): Saliva secretion rate and salivary IgA levels significantly increased (p<.01) and decreased (p<.05). HR significantly decreased (p<.05). P300 amplitude significantly increased (p<.05). No significant physiological effect was found in noise and silence, while saliva secretion rate significantly increased (p<.05) in silence. Our results of salivary IgA and HR suggest that the calculation task activates immune and sympathetic nervous system and, in contrast, music alleviates such symptom. On the other hand, the result of P300 amplitude suggests that the central nervous system for the recognition information processing is inactivated by the calculation task, and it can be recovered by music. In this study, we introduced various types of physiological indices, and future works are promising to clarify the mechanism of physiological effects of music.