Tech Tuesday

Tom Powell shares:

I must be one of the luckiest people in the world. I am a speech pathologist at JCPS and I get to work with one student in particular who has a severe stuttering disorder. When I received my WHAS Crusade iPad, I immediately got excited about being able to try a Delayed Auditory Feedback (DAF) app with my student who stutters.

Stated simply, Delayed Auditory Feedback is extending the time between when we speak and when we hear ourselves speak. The iPad App that I found is called DAF Pro, and according to the App Store Preview, can be used only with iOS (or Apple) devices. DAF Pro claims that the delay in feedback causes the speaker to slow their rate of speech, which in turn decreases the amount of dysfluencies experienced. Coincidentally, this is also the App used by Cindy Simpson, M. S. CCC-SLP, one of our JCPS ECE Assistive Technology Liaisons. Cindy was able to provide an iPad for one of my student to trial. The iPad was made available to this student based on many factors including the fact that this student has a severe stutter and qualified to try a speech generating device to augment verbalizations when his communication breakdowns occurred. While assessing the student, Cindy suggested that we also try the delayed auditory feedback approach as well. Like most delayed auditory feedback devices, DAF Pro works by downloading and opening the App, inserting headphones, and then speaking. My student is using wired earbuds, but either a wired or Bluetooth earpiece will function properly. The microphone picks up the speakers voice, then after a slight delay, the speaker can hear her/his voice “echoing” everything they say.

DAF works on the principle that fluency is often increased while singing, speaking in unison with others – such as reciting the Pledge of Allegiance, or even just paying attention to background chatter at, say, a cocktail party. DAF Pro is an example of a delayed auditory feedback device in its least expensive format. If DAF is found to be useful to an individual, a more expensive, and perhaps more convenient version could be a custom molded Bluetooth earpiece used with a smaller iPhone with an appropriate DAF App. The DAF Pro works similar to a hearing-aid-like device that plays the stutter’s speech back to her or him, sometime in a slightly altered form, after a split-second delay. Research shows that used alone, delayed auditory feedback is rarely a magic pill, but can be used with other more traditional approaches like decreased rate of speech, using easy onset and working through stutters in a relaxed manner.

Like most delayed auditory feedback devices, in addition to offering a delayed feedback option, the DAF Pro App also allows the user to alter the pitch and volume of the feedback voice, and also allows for adjustments to the background noise. Through experimentation, the most effective settings for pitch, volume, background noise and amount of delay can be determined for each individual user. This blogpost is in no way meant to be a research article since my sample size is one. There are heartwarming stories on YouTube showing a similar delayed auditory feedback device called SpeachEasy being used with almost instant success. (minute 5:05). I wish I could say that my student was cured instantly, but that simply is not the case. For now, I will continue to work with this student, but am very happy that I have had the opportunity to try DAF Pro and I am looking forward to future success with this and every other student I get the privilege to work with.


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