Initial VAST™ Clinical Trials
at the Stroke Comeback Center
Experimentation related to the use of VAST began at the Stroke Comeback Center in the Fall of 2009. 6 individuals have been enrolled in the trial program to accomplish 2 goals: 1) to collect user information related to best uses of the technique and 2) to collect efficacy data.
Since the technique had been used by only a few individuals, there were a number of unknown variables surrounding its use. The key components of user feedback related to:
- Accessing the videos
- Achieving independence in practicing with videos
- Differentiating between a therapeutic use of videos and a functional use of videos
- Preferences in variations in oral movements: preciseness of oral movements and preferences between lip models
- Experimenting with variations in prosody, intensity, length of script, practice schedules
- Generalization effect
The physical management of an iPhone or iPod touch can be challenging particularly for those users who have a hemiparesis. Locating and activating specific videos were less problematic than using Pause, Volume and Replay features. Repetition and, in some cases, separate visual support was required to achieve independence in accessing and working with the videos. A key component seemed to be the time and duration of fingertip pressure on the touch screen; lightly tapping the screen had to be taught as an acquired skill.
All videos can, and should, be used as a therapeutic tool. However, therapeutic videos focus on a different outcome. The users were encouraged to focus on various aspects of speech production when practicing with therapy videos, for example, focusing only on inclusion of all phonemes in the word, differentiating between minimal pairs (or contrasting phrases) and controlling volume. These motor speech production elements were not ignored when practicing with Functional videos, but the emphasis was more on allowing automatic aspects of speech to take over - to listen and internalize the production of the script.
Several individuals were used as lip models in the production of trial videos. The participants in the trial group expressed definite preferences between the various models, primarily based on physical characteristics of the speaker. However, it is important to note that, despite preferences, success with the technique was not dependent upon the physical characteristics of the speaker. All of the participants in the trial group could use the technique with all of the lip models.
The initial trial group experimented with changes in length of script, practice schedules, volume, and rate, rhythm and pausing. Length of script varies with the user, although in every case with the trial participants, the user exceeded their own expectation as to the length of the script - i.e., if they predicted they would only be able to use a short paragraph length script, they exceeded this expectation in every case. When using the iPod touch there is, of course, a wide variation in the intensity at which the script is played. Participants in the trial group tended to set the volume at too high an intensity which caused a change in their vocal quality while speaking with the video. Volume appears to be an individualized function, but it is recommended that as low an intensity as possible be used during use of the video. Amount of practice also varied considerably across users. Data regarding this variable will continue to be collected in additional clinical trials. Primary emphasis was placed on prosodic factors. These appear to be key elements in the successful use of VAST. Length of pauses, rate of speech, rhythm patterns and changes in pitch made a significant difference in ability to readily internalize the patterning of each script and use it successfully. The conclusions determined by experimentation with these variables have been incorporated into all of the videos produced for SpeakinMotion.
There has been some generalization effect noted among the initial trial participants, particularly in their ability to respond spontaneously to personal questions after practicing with a personal script. This generalization effect will be included as a part of the expanded clinical trial program.
Additional experimentation and a larger number of participants are indicated to continue to perfect production of the videos and to discover other success factors. For this reason, we are expanding clinical trials at other sites to collect additional information.