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CDT’s newest product line is called SPATS, which stands for Speech Perception Assessment and Training System.  The first version, now designated SPATS-HI (SPATS for Hearing-Impaired Persons), was developed as a system for teaching hearing-aid and cochlear-implant users more accurately to identify the speech sounds heard through those assistive devices.   It had often been suggested that some listeners may not do well with aided listening because they persist in attending to the speech cues they formerly relied on, but which their hearing loss may have rendered inaudible.  Others with similar losses apparently do better because they learn to use alternative cues that can be heard through their aids or implants.  Research has supported this prediction.  It was found that all users trained with SPATS-HI improved, some by modest amounts and others by much more.  SPATS-HI combines recognition drills using more than 100 of the basic sounds of English, with training on meaningful sentences spoken by twelve different talkers.  The scientific reasoning that led to the development of SPATS-HI and research showing its successful use with hearing-aid users are reported in two articles in the Hearing Journal (Watson et al., 2008; Miller, Watson, Kistler et al., 2008).  Additional descriptions of SPATS-related research are available in two other articles available online (Miller, Watson, Kewley-Port et al., 2008; Miller, Watson, Kistler, Wightman & Preminger, 2008). 

Following the successful use of SPATS-HI with hearing-impaired listeners, it was recognized that persons learning English as a second language (ESL students) often have similar perceptual difficulties with speech.  Many non-native speakers persist in attending to features that distinguish the sounds of their native language, but which may be much less useful for the identification of English speech sounds.  A version of SPATS was therefore developed for that population.   There are now two distinct versions of SPATS, one that has been refined for use with hearing impaired persons (SPATS-HI) and a second system that has been adapted for students of English as a second language (SPATS-ESL).   SPATS-HI is described below. Click here >> SPATS-ESL for a description of the application for second-language learners.


CDT’s speech training software for hearing impaired persons, SPATS-HI, is available through audiological clinics in which a certified audiologist has been trained in the use of this system.  It is intended that SPATS-HI speech perception training be conducted at least initially in the clinic, with regular monitoring of performance by a supervisor.  After 8-10 hours of training it is quite feasible for clients with at least modest computer skills to use a copy of the system on a home computer, assuming it is equipped with an adequate sound card and loudspeaker (see discussion in User’s Guide). 

There is an apt analogy between SPATS-HI training and the study of the piano. Nothing but self-directed home study might be sufficient for a few very unusual students to learn to play that instrument.  But the vast majority of piano students will learn to play only if they have periodic sessions with a teacher who gives them feedback, admonitions about practice, reinforcement for their achievements, and new assignments. And they DO learn to play, and their achievements eventually amaze those of us who lack that skill. Learning to perceive the complex code that is represented by the sounds of English, when that code has been transformed by a hearing aid, is a perceptual skill that improves with practice as do perceptual-motor skills like playing the piano and playing tennis.  Periodic sessions in which a supervisor provides evaluative feedback and guidance for future training sessions are an important part of SPATS-HI training, and in fact are absolutely essential for trainees to enjoy the maximum benefits of aided listening.

Contact us for the names of audiology clinics or speech and hearing centers near you where SPATS-HI training is available.  If none make training available, direct them to contact us at the address below to learn more about the system and perhaps to consider becoming a certified SPATS-HI training facility. 
[certification@comdistec.com; or call 812-336-1766]. 

For technical information about the clinical validation of the SPATS systems, please email Dr. James D. Miller at   [jdmiller@comdistec.com] or refer to the published reports listed below.


Audiologists or other hearing health care professionals interested in licensing SPATS-HI should contact CDT or call (812) 336-1766.

The SPATS speech-perception training systems, SPATS-HI and SPATS-ESL, are highly evolved applications that assess trainees’ skills and automatically present a training curriculum that is designed to yield the most improvement possible per hour invested in training. These systems benefit from some supervision by a clinician or teacher who has been trained in their use.  Training for SPATS supervision can be provided in one or more 2-3 hour workshops by arrangement.  Training sessions are be available in the form of virtual visits to CDT, conducted by a combination of conference telephone calls and online instruction with the actual programs using GoToMeeting software. If you are interested in participating in one or more of these online workshops, please contact us and indicate whether your interest is in SPATS-HI, SPATS-ESL, or both.  Also, please join our mailing list so that we can inform you of new items on our web site and about other upcoming SPATS-related events.

For other information about SPATS training systems, please contact Dr. James D. Miller.
Email: jdmiller@comdistec.com
Telephone: (812) 336-1766

Or mail inquiries to:
Dr. James D. Miller
Communication Disorders Technology, Inc.
3100 East Hinkle Place, Ste 107
Bloomington, IN 47408


Watson, C.S., Miller, J.D., Kewley-Port, D., Humes, L.E., and Wightman, F.L. (2008) “Training listeners to identify the sounds of speech: I. A review of past studies.” The Hearing Journal 61(9), 26-31. 
»Full Text

Miller, J.D., Watson, C.S., Kistler, D.J., Preminger, J.E., and Wark, D.J. (2008) “Training listeners to identify the sounds of speech: II.  Using SPATS software.” The Hearing Journal 61(10), 29-33. 
»Full Text

Miller, J.D., Watson, C.S., Kewley-Port, D., Sillings, R., Mills, W.F., and Burleson, D.F. (2008) “SPATS: Speech Perception Training and Assessment System.” Proceedings of Meetings on Acoustics 2:05005 (17 pages). 
»Full Text

Miller, J.D., Watson, C.S., Kistler, D.J., Wightman, F.L., and Preminger, J.E. (2008) “Preliminary evaluation of the Speech Pereption Assessment and Training Sysetem (SPATS) with hearing-aid and cochlear-implant users.” Proceedings of Meetings on Acoustics 2:05005 (9 pages).
»Full Text

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Communication Disorders Technology, Inc.
3100 East John Hinkle Place, Ste 107
Bloomington, IN 47408
Phone:   1-812-336-1766
Fax:   1-812-822-3438
E-mail:   cdt@comdistec.com