Reduced vocal intensity (hypophonia) is a hallmark motor speech symptom of Parkinson’s disease (PD) and  while the physiologic causes of motor speech changes in PD are not completely understood an impairment in accurate self-perception of speech has been identified as a common problem associated with PD causing many patients to have difficulty performing a task when reliant solely on an internal cue. With regards to speech production, many individuals with PD often overestimate their level of vocal intensity and when cued to speak at a more normal level of loudness (which many patients can do), they may insist: “this feels to loud,” I can’t talk this loud.”

When performing vocal function exercises at home as a part of a speech therapy program or after discharge from treatment, the lack of accurate self-perception may impact independent speech and voice practice, as individuals may not accurately judge the amount of effort required to perform the vocal function exercise’s in order to gain strength and carryover to every day speech.

Can You Hear Me Now?

You might be surprised to know that most patients with hypophonia associated with PD CAN BE LOUDER in response to an external cue. Capitalizing on this ability is the goal of many speech therapy approaches, and while individual therapists might employ different protocols, encouraging patients to perform daily high effort vocal function exercises is typically a component of all speech therapy approaches, as this can help to increase the strength of the respiratory and laryngeal muscles and build the endurance needed for all day voice use.

The Hi-Volt® voice-on-light is a calibrated, voice-activated feedback tool that may help individuals with Parkinson’s perform speech practice more efficiently on their own and help them feel the effort they need to use to generate a loud enough voice to obtain some strengthening effect and endurance for everyday conversation.

Frequently, it is introduced during speech therapy treatment, with a single cue: “speak loud enough to activate the light.” At home individuals can use the Hi-VOLT® during their speech practice, and, because the light is housed within a bracelet, they can also use it during physical therapy as an external cue for loudness when counting exercise reps.

Augmented Feedback and Skill Learning

Feedback during exercise can come in many forms but it’s primarily used to guide performance to an intended outcome. Giving augmented feedback is a significant role for a speech or physical therapists when working with patients with Parkinson’s disease (PD), as these patients  often under scale movements and voice. External feedback tools can be helpful to patients in and out of therapy, helping them re-calibrate to normal by seeing and feeling the effort associated with specific tasks such as walking and speaking.

Augmented feedback can save a learner time and energy in learning skills, and also add to information detected as well as information one cannot detect. External feedback helps a learner achieve a goal more quickly (guidance); influences the person’s perception of his/ her own ability in a skill (motivation); and improves the chance that the performer will repeat the performance (re-inforcement).

Acoustic data for 98 PD patients was reviewed.Rounding up, the median loudness without feedback was 74.0 dB SPL, and the median loudness when using the Hi-VOLT was 80.0 dB SPL. The increase in loudness that occurred when the patients used the Hi-VOLT is greater than would be expected by chance, and is therefore, statistically significant. The p-value of <0.001 indicates that there is less than a tenth of a percent chance that this increase in loudness occurred by chance, meaning that the difference is highly likely to be the result of using the Hi-VOLT®

Find out for yourself or for your patients.  Add the Hi-VOLT® for PD audio of guided practice and strengthen your voice at home, in the car, or wherever you go!

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My Mission: To enlist individuals in their treatment, and help them express their personality & spirit through voice. To educate  and empower. Mary Spremulli, MA, CCC-SLP * FiTOUR® Group Exercise Instructor * Voice Aerobics® A Whole Body Approach to Voice Practice

Voice Aerobics the heART and Science of Voice Practice