Kris S. Chesky, University of North Texas, Southern Methodist University, University of Texas at Arlington

George V. Kondraske, University of Texas at Arlington

Over the past decade, an interest in the involvement of the human somatosensory system in musical processing, performance, and perception has resulted in many interesting articles and applications of acoustically produced vibration. In a 1992 edition of Music Perception, authors described the receptive and response processes involved in vibrotactile stimulation (Verrillo, 1992), the potentially useful feedback signal available to musicians through this sense (Askenfelt & Jansson, 1992), and the possible implications for phonation control from chest wall vibrations produced during singing (Sundberg, 1992). Also suggested, is that vibration feedback from internal voice sensitivities provides landmarks for controlling vocal emission that may be more reliable than auditory feedback (Scotto Di Carlo, 1994).

Applications of music vibration has also been of interest to researchers in music in special education, music therapy and music medicine. Chesky and Michel (1991) presented a conceptual model (the "Two Pronged" approach) for using music vibration as a means for pain relief and introduced the Music Vibration Table (MVT™). Using the MVT™ technology to measure and control the music vibrations while patients were being stimulated, reports (Chesky, 1992; Chesky, Rubin, Cortez, & Pertusi, 1992) showed statistically significant reductions of pain for rheumatoid arthritis patients attributable to music plus music vibration as compared to music alone or placebo. These authors (Michel & Chesky, 1993; Michel & Chesky, 1994, in press) have stressed the importance of scientific methodologies in research and clinical applications of music vibration. In addition, several technical, engineering and design issues relevant to music vibration technology have been presented (Chesky, Michel & Kondrakse, 1994, in press).

The MVT™ system consists of three independently controlled sub-modules and a single main control unit. The system is designed to implement a closed-loop adaptive control scheme that compensates for both variability in the frequency content of music sources and load variations on each sub-module independently to produce a desired vibratory stimulation profile over the course of a treatment or research session.

The purpose of this paper is to describe vibration profiles over time produced from two different music sources. This is to show not only the kinds of graphical and quantitative analysis that the MVT™ can produce, but also the wide differences in vibration content (i.e., not musical content) delivered with different music selections. From this perspective, the researcher is able to quantify a stimulus delivered and therefore make decisions regarding the influences of the music used to create the vibration, selected algorithms programmed into the MVT™ microprocessor, and the subjects weight and displacement on the membrane.

The following consists of graphs showing the vibration profiles over a ten minute period of two music selections used in a recent study examining the effects of music listening and music vibration on spatial processing abilities (Flohr, Persillin, Flohr, & Chesky, 1995). The graphs shows displacement of vibration (in micrometers) at three different frequencies (100Hz, 175Hz, and 250Hz), first together and then for the frequency bands independently including means and standard deviation indicators. The six graphs that follow indicate the percentile distributions of displacement for each of the three frequency bands.

For this analysis, the MVT™ was programed to allow for complex vibration in the range of the Pacianin corpuscle (60-300Hz.) and to quantify vibration at three frequency bands within this range (100Hz, 175Hz, and 250Hz).

* This music is the first ten minutes of a CD titled "Singles" distributed on Epic Records and includes songs by Alice in Chains and Pearl Jam