# A Wearable Sonification System to Improve Movement Awareness: A Feasibility Study
## 6 Discussion
### Enhancing Kinesthetic Awareness through Discrete and Continuous Auditory  
This study has illustrated a dual strategy of auditory cues for movement awareness, comprising continuous and discrete sounds. The CAF system, intricately mapped to a continuous data stream, allowed the participant to cue their movement and correct their position back to a reference region to attain balance. This approach is built on the dynamic auditory response that directly mirrors the participant's spatial orientation in relation to the reference region boundary. The continuous tones that varied in brightness correlate with the rotation intensity. As the participant's rotation increased, the tones brightened, enhancing the auditory representation of movement magnitude. Conversely, as the rotation decreased, the tones became progressively duller, providing an intuitive auditory dimming in response to the reduced activity (Figure 7).  
In addition to continuous tones, the system incorporated a discrete bell tone to signal deviations from the reference region within the sagittal plane. This discrete auditory cue provided a clear and immediate indication of movements that exceeded the predefined threshold, acting as an alert mechanism to return to the reference region. Interestingly, these results were most evident in the eyes-closed settings, where the amount of sway and the time it took to return to the center of the reference region was reduced with the aid of auditory feedback (Figure 8). This observation agrees with earlier research on stance and audio biofeedback ([42; 44]) that found a reduction in postural sway in eyes-closed participants with the addition of audio biofeedback, as it helped the participants partially overcome the deficit in visual feedback. Another study [40] has shown that adding white noise has reduced postural sway in eye-open and eye-closed standing balance tests.  
The effectiveness of the proposed system in aiding participants in returning to their reference region was evident in the results. Upon analyzing the audio files generated for Tests 3 and 4, a few initial observations can be made. In Test 4, the bell tone provided a clear indication when the reference region was exceeded; this was a clear cue for the participant to return to the reference region, and this correction took a mean of approximately 5 scompared to a mean of roughly 15 s in settings without auditory feedback. The continuous sound, represented as a sharpening tone before the bell tone, provided a cue to participants to anticipate the reference region boundary. Specifically, in Test 3, the bell tone only signaled one reference boundary crossing. The eyes-open condition did not require the auditory sense as much as that of closed eyes. This was most evident when comparing the time series graphs of the rotation angles for Tests 3 and 4 (Figures 6 and 8).  
This initial analysis underscores the essential role of auditory feedback in balance control and postural stability. This finding agrees with previous studies demonstrating that auditory feedback effectively reduced postural sway in various sensory conditions [40; 42; 44]. While confirming the potential of auditory feedback in therapeutic applications to enhance balance, its application in gait analysis presented in our previous study [45] is important. We noted there that it is crucial to distinguish a focus of the study, which here is balance, whereas the earlier paper [45] was focused on gait. Given the differences between movement types and assessment objectives in these two studies, a direct comparison may not yield meaningful insight. We believe that this current study, focused on balance, contributes to understanding the application of auditory feedback in balance control. Moving forward, we suggest that future research focus more on gait analysis. That would entail exploring how auditory feedback could effectively be integrated into gait training and rehabilitation, thereby extending the scope of its application.