The Effects of Stimulative vs. Sedative Music on Reaction Time

Transcription

1 The Effects of Stimulative vs. Sedative Music on Reaction Time Ashley Mertes Allie Myers Jasmine Reed Jessica Thering BI 231L

2 Introduction Interest in reaction time was somewhat due to a study done on reaction time and visualmotor tasks found during initial research on varying biological functions. This study explored the operations that take place in the brain by subjects who observed the presented visual stimuli and obtained the behavioral responses of the subjects which directly correlated with the research done(braun et al, 2003). Another reason that this particular correlation stood out was how it is cross-disciplinary. This research could prove important to the field of biological science as well as that of music therapy, because knowing and understanding how music affects the body physiologically covers both areas of research. This topic helped to create a bridge between science and music (as those in both fields were working on it together). Also, when we conducted a review of the literature, we found very little on this subject (specifically, reaction time as it relates to the type of music being played). Many reports have been done on the effects of sedative and stimulative music on many of peoples other natural physiological rhythms and patterns, (i.e. heart rate and blood pressure) (Lorch et al, 1994). Needless to say, this adds appeal. Sedative music is defined as that lacking strong rhythmic elements, has softer dynamics, and contains notes in close proximity (Taylor, 1973). Stimulative music is defined as having a strong rhythmic element, is percussive, and possesses a faster tempo (Taylor, 1973). Organs used for listening to the music would add the outer, middle, and inner ears (excluding the parts of the inner ear used for maintaining balance), as well as the auditory cortex, which would receive the compressed signal and subsequently interpret it. Reaction time could include the fine motor cortex of the brain, the oculomotor nerve, skeletal muscles, and the metacarpals (Seeley et al, 2007).

3 Our hypothesis was that while listening to sedative music, our subjects would maintain slower reaction times due to its possible lulling effect, which would lower the heart rate to a more restful point and perhaps decrease a subject s ability to react quickly to a perceived stimulus. Conversely, while they were listening to music that was stimulative, they would have an increased reaction time due to the loud, fast music bringing on an activation of the sympathetic nervous system (also known as the fight or flight nervous system). When they listened to no music, the test subjects would probably display a reaction time between the two of these. This could be due to entrainment, which is when a body matches its internal conditions with an external stimulus (in this case, the stimulus would be music). According to Taylor, the human body often entrains to beats per minute. Methods & Materials There were 25 subjects in all (all were females between the ages of 18 and 24). Subjects were set in front of a computer with headphones and proceeded to go to the website where they were shown an animation of a stoplight and were asked to click a button when the stoplight turned green. The amount of time it took each subject to do this was measured in seconds (usually amounting to a decimal). Each person did the activity under every condition three times; once with no music, once with sedative music, and once with stimulative music. The three times taken per condition were averaged together and this was then recorded and the subject was assigned a letter to record along with her reaction times. The sedative music used was the song When You Say Nothing At All, by Alison Kraus. The stimulative music used was Robot, by T.A.T.U. Equipment used to play the music

4 was a computer with accompanying headphones. Music was played using an mp3 file on the computer. Results The average reaction time for subjects listening to no music was seconds with a standard deviation of seconds. When subjects were listening to sedative music, the average reaction time was seconds. The standard deviation was seconds. When listening to stimulative music, subjects responded with an average reaction time of seconds, with a standard deviation of seconds. The T-Test between the no music and sedative music conditions resulted in a p-value of (meaning that the results were not significant). The T-Test done between the no music and stimulative music conditions displayed a result of (also statistically insignificant). However, the T-Test between sedative and stimulative music conditions showed a p-value of , meaning that the difference between these two conditions is significant. The graph of the average reaction times during each condition is shown below in Figure 1.

5 No Music Sedative Stimulative Averages Std.Devs Our hypothesis was only partially supported by these statistics. The results of the averages of the experiment seem to show that the subjects responded more slowly when listening to sedative music than to stimulative or no music, particularly to stimulative music. In addition to this, subjects responded most quickly when listening to stimulative music, as hypothesized. On the other hand, it was only the difference between sedative and stimulative music that was statistically significant. Listening to no music showed no significant difference either to sedative music or to stimulative. Discussion One of the things that helped us out when we conducted the study was the accuracy of the website used to calculate the response times. The website also calculated the averages

6 automatically which eliminated the possibility for human error. The website was very easy to use and required little instruction. One of the factors that may have affected this experiment was the use of vocal music rather than instrumental music. The music that we used was, in fact, vocal, and may have caused problems due to the distraction (focus on the lyrics could have affected this). The music itself presented other problems as well. Along the same lines, whether or not the subjects liked the music became a bit of an issue. The one song, Robot, was in Russian so there was a difficulty and some slight irritation with the language barrier, as well as the techno genre of this song. On the other hand, there were also subjects who knew of the artist. The other song, When You Say Nothing At All, was a slow acoustic song (a less popular genre right now by far). Many subjects commented on how much they disliked country music, although technically that wasn t the genre of the song. Mild fatigue could have played a role in the results because each subject had to perform the experiment three times for each condition. By the time that the stimulative condition took place, the subject may have lost interest. Something that we did not anticipate as being a problem was that the results depended on the subject reacting by clicking the mouse button. This same method was used for all three music conditions three times each. There was, actually, some confusion as to what mouse click was being used for what function. There was also the subjects mood that needed to be considered. Anything that involved their life circumstances could not be controlled. Things such as fights with friends, finally getting that special someone to ask you out, or even looking forward to lunchtime could have affected distractibility. While they may not have had much impact on our results (as the same

7 person participated in all three tests), it is possible that controlling these in the future may impact results of experiments measuring something similar. Future research on this topic could benefit both science and Music Therapy in many ways. An obvious way to use reaction time and music would be when studying safe driving practices. Research like this could create new channels of communication for professionals of varying disciplines. Also, this could be beneficial in Music Therapy when working with other therapists (physical, occupational, etc.), perhaps while exploring the most effective means to assist a client in daily life and help attain client goals. The hypothesis was partially supported. According to the T-Test, the sedative music and stimulative music conditions were significantly different from each other; however neither condition was significantly different from the no music condition (our control group).

8 References Allen, J. (2002). The Online reaction time test. Retrieved from Braun, J. W., Rousson, V., Simpson, W.A., & Prokop, J. (2003). Parametric modeling of reaction time experiment data. Biometrics, 59(3), Katina, E. & Volkolva, L. (2002). Robot. On Dvesti Po Vstechnoi. [CD]. Russia: Russian Ent. Lorch, C., Lorch, V., Diedendorf, A., & Earl, P. (1994). The effect of stimulative and sedative music on systolic blood pressure, heart rate, and respiratory. Journal of Music Therapy, 31 (2), Overstreet, P. & Schlitz, D. (1988). When You Say Nothing At All [Recorded by Alison Krauss and Union Station]. On Now That I've Found You: A Collection [CD]. Massachusetts: Rounder. (1995). Seeley, Rod R., Stephens, Trent D. & Tate, Philip. (2007). Anatomy & Physiology, 8 th edition, McGraw Hill Publisher. Taylor, Dale B. (1973). Subject responses to precategorized stimulative and sedative music. Journal of Music Therapy, 10 (summer),