Abstract
This study examined the preference of music loudness that incrementally increased and decreased while subjects performed a gross or fine motor task. A total of 64 college students listened to recorded popular music in the 9-minute individual experiment. In the gross motor group, subjects were asked to move up and down in small steps. In the fine motor group, subjects were observed tapping the fingers of one hand while sitting in a chair. Music loudness was the independent variable that incrementally increased from 65 to 85 dB and then decreased from 85 to 65 dB with a 5-dB change per minute. Subjects rated loudness preference every 30 seconds using a 5-point scale, thus, subjects rated loudness 2 times per minute. The dependent variables were loudness preference, behavioral responses, and heart rate. Heart rate was measured before, after the experiment, and after subjects completed a questionnaire. Ratings of loudness preference and heart rate were analyzed by the two-way analysis of variance (ANOVA) concerning gross versus fine motor groups, males versus females, and musicians versus non-musicians. Loudness preference ratings were also compared in loudness increasing versus decreasing mode and first versus second ratings at each dB level. The changes in subjects' synchronous movement and movement levels were observed and analyzed by the Friedman two-way analysis of variance by ranks. Observation reliability was 98.7%. Facial expressions and associated behaviors were also observed when music intensity increased.
Results indicated that throughout the session the fine motor group perceived music significantly louder than the gross motor group. Females perceived music significantly louder than males when the music intensity reached 80 dB. Significant interactions were found between loudness preference and 2 ratings at the same intensity levels. Subjects in both gross and fine motor groups increased comfort levels in the second rating regardless of whether they perceived music as soft or loud in the first rating. Significant interaction was also observed between music experiences and 2 ratings. Musicians quickly became accustomed to music at high intensity levels, and non-musicians quickly became used to music at low intensity levels. Subjects perceived decreasing sounds significantly softer than increasing sounds. Heart rate significantly increased after the experiment and significantly decreased after completing a questionnaire in both gross and fine motor groups. Movement levels significantly changed throughout the session. Music intensity changes correlated with movement levels. Synchronous movement and movement levels significantly changed during the first 2 minutes. Subjects who perceived the music to be loud exhibited more facial expressions and associated behaviors of discomfort when music reached high intensity levels. The following were also discussed: the effects of body movement on loudness preference, auditory functions associated with loudness habituation, methodological issues to measure preference of loudness that changes over time, and implications for therapeutic applications.
|
