FAQ #3 - Electronic Devices for Stuttering August 22, 1995 Send comments to: firstname.lastname@example.org The author, Thomas David Kehoe, is owner of Casa Futura Technologies, president of the San Jose chapter of the National Stuttering Project, and a member of the American Speech-Language Hearing Association. AUDITORY FEEDBACK DEVICES FOR IMMEDIATE FLUENCY Delayed auditory feedback (DAF) delays your voice to your headphones a fraction of a second (in the 25-250 millisecond range). Frequency-altered auditory feedback (FAF) alters the pitch of your voice in your headphones. Laryngeal auditory feedback (LAF) uses a throat microphone to pick up your vocal fold vibration. The device then electronically alters the signal into a buzzing sound, to sound more like your actual vocal fold vibration. These types of auditory feedback enable vocal awareness and control, immediately reduce stuttering, with no training or mental effort.(3) Your voice sounds natural. You just put on the headphones and talk. These auditory feedback effects have suggested to researchers that stuttering is caused by defective hearing, or an auditory disfunction.(4) However, despite decades of research, no such hearing defect has been found. A normal auditory function may contribute to stuttering, and explain the effectiveness of the electronic devices. The stapedius muscle reflex of the middle ear muscle attenuates your vocal perception 5-15 dB.(5) If you can't hear your voice clearly, you can't control it. Paradoxically, electronically altering your voice to sound like someone else overcomes the stapedius muscle reflex. You then hear your voice clearly, control your voice, and talk fluently. If you only stutter in certain situations, such as public speaking or on telephones, a DAF, FAF, or LAF device may be all you need. The effect is useful in stuttering therapy. If your speech pathologist taught you fluency shaping speech motor skills, but you're having trouble using these speech motor skills outside the clinic, a DAF, FAF, or LAF device gives you the vocal control to stay on-target. If you continually use your fluency shaping speech motor skills for many hours of talking, you should be able to discontinue using the device and continue to talk fluently. A DAF, FAF, or LAF device can help you eliminate speech-related fear and anxiety, such as fear of telephones. Many stuttering therapies train you to use slow, prolonged speech. A long DAF delay and/or a lower FAF pitch slows down your speech. The goal is not for you to talk abnormally slowly forever. Rather, the slow, deliberate movements help you develop speech motor skills. The training should lead to fluent speech at normal speaking rates without the device.(6) A short DAF delay and/or higher pitch FAF can increase your speaking rate, while improving fluency. If you use DAF/FAF to talk faster, you won't develop carryover fluency. The DAF/FAF effect may even wear off, and you'll stutter when using the device! DAF, FAF, and LAF may be used occasionally without therapy. The devices should be used for extended periods only under the supervision of a speech pathologist. BIOFEEDBACK DEVICES FOR STUTTERING THERAPY Biofeedback devices provide information to a user about physical processes or behaviors. These devices require training from a speech pathologist. The devices improve your awareness and control of physical aspects of speech, or speech motor skills. The devices usually provide visual feedback. The visual feedback can be a row of green and red lights. Or it can be a computer display. Some devices even have video games. The most widely-used devices are: - Vocal amplitude rate-of-change devices train the loudness contour or gentle onset fluency shaping speech target. A smooth increase in vocal volume at the beginning of each phrase, and a constant vocal volume until the end of the phrase, indicates continuous phonation. - Vocal pitch. A low vocal pitch indicates relaxed breathing, continuous phonation, and slow, prolonged speech. A high vocal pitch indicates high articulatory muscle activity, high respiratory muscle tension, and fast speech. - Respiration monitors show your breathing on a computer, from a strap around your chest. - Electromyographs (EMG) use three electrodes taped to your neck and jaw to monitor speech-production muscle activity. The device indicates when your speech-production muscles are tense. EMG therapy trains you to talk with relaxed speech-production muscles.(8) TRANSFER WITH ELECTRONIC DEVICES You and your speech pathologist should plan what an electronic device will train you to do, and how you will phase out using the device. For example, you may follow this plan: 1) Learn fluency shaping speech motor skills from a speech pathologist. Discuss your speech-related fears and anxieties with your speech pathologist. 2) Use the device to enable these speech motor skills outside the clinic. At the same time, use the device to reduce speech-related fear and anxiety. 3) Switch off the device for short periods of time, in relaxed situations, and continue to use fluency shaping speech motor skills. Increase the length of these periods, in more stressful situations. When you can talk fluently anytime, anywhere, discontinue using the device. THE CAFET BIOFEEDBACK SYSTEM The Computer-Aided Fluency Establishment and Trainer (CAFET) is a computer-based device combining a respiration monitor and a gentle onset monitor. This combination trains seven fluency shaping motor skills. Visual feedback includes video games. After the CAFET trains you to talk fluently, it trains you to no longer need the device. At first, you see both a graphical display of the your speech and text error messages. After successfully completing a series of exercises, your speech pathologist switches off the graphical display. You just read error messages when you make a mistake. When you don't make a mistake, you see nothing. After successfully completing more exercises, your speech pathologist switches off the real-time display. You don't see anything until the speech task is completed, and then error messages are displayed. One study found that 92% of users were fluent two years after completing the program.(9) CASA FUTURA TECHNOLOGIES AUTOMATIC BIOFEEDBACK SYSTEMS Casa Futura Technologies' biofeedback devices automatically reduce auditory feedback as you improve your speech motor skills. The devices monitor your speech through vocal pitch or electromyography. When your speech is relaxed and slow, the device switches off the auditory feedback. When your speech is fast or tense, the device switches on DAF and FAF, to slow your speech. You try to relax and keep the auditory feedback off during conversations. When you can talk fluently without auditory feedback, you discontinue using the device and continue to talk fluently. One device is pocket-sized and wearable. One device plugs into telephones, or may be used in speech clinics or at home for practice. THIRD-PARTY PAYMENT - NYNEX provides Casa Futura Technologies telephone devices to Massachusetts residents who stutter. California, Minnesota, and Montana telephone company approval is expected in 1996. - State vocational rehabilitation programs may provide electronic devices or speech therapy for unemployed adults who stutter. - The Individuals with Disabilities Education Act (IDEA) helps children with disabilities. Ask your child's school principal or speech pathologist. - The IRS allows you to deduct speech therapy equipment on Schedule A, if your total medical expenses exceed 7.5 percent of your adjusted gross income. - Federal Supplemental Security Income helps low-income children with disabilities. - The Americans with Disabilities Act (ADA) requires some employers to provide devices, and then reimburses some of these employers 50%. You should qualify if your job requires talking, and stuttering interferes with your job. You also qualify when applying for or seeking a promo- tion to such a job. You must ask the employer for a reasonable accom- modation, such as an electronic device, speech therapy, or a different work assignment. Your employer is not allowed to suggest such an accommodation. The employer is required to provide the reasonable accommodation, or find an alternative. Smaller employers receive a tax credit for half of the cost (Section 44 of the Internal Revenue Code). The IRS may also give an employer up to $2400 for hiring you, under the Targeted Jobs Tax Credit Program. Call (800) 669-EEOC for the Technical Assistance Manual of the ADA. REFERENCES (3)Kalinowski, J., Armson, J., Stuart, A., Gracco, V., Roland- Mieszkowski, M. "Effects of alterations in auditory feedback and speech rate on stuttering frequency." Language and Speech, 1993, 36, 1-16. 50 ms DAF and/or 1/2 octave FAF reduced stuttering approximately 80% during reading, while increasing speaking rate. Brenaut, L., Morrison, S., Kalinowski, J., Armson, J. "Effects of Altered Auditory Feedback on Stuttering During Telephone Use." Dalhousie University, Halifax, NS, Canada. 55 ms DAF reduced stuttering 50%, DAF and FAF reduced stuttering 75%. (4)Wolf, A.A., Wolf, E.G. (1959). "Feedback processes in the theory of certain speech disorders." Speech Pathology and Therapy, 2, 48-55; Mysak, E.D. (1960). "Servo-theory and stuttering." Journal of Speech & Hearing Disorders, 25, 188-195; Yates, A.J. (1963). "Recent empirical and theoretical approaches to the experimental manipulation of speech in normal subjects and in stammerers." Behaviour Research and Therapy, 1, 95-119; Butler, B.R., Stanley, P.E., (1966). "The stuttering problem considered from an automatic control point of view." Folia Phoniatricia, 18, 33-44; Webster, R.L. & Lubker, B.B. (1968). "Interrelationships among fluency producing variables in stuttered speech." Journal of Speech and Hearing Research, 11, 754-766. (5)Shlomo Sillman, The Acoustic Reflex (1984). San Diego: Academic Press. (6)Ryan and Van Kirk. "Establishment of fluent speech in 50 stutterers using DAF and operant procedures." Journal of Speech and Hearing Disorders, 1974 Feb;39(1). DAF therapy reduced stuttering from an average 9.2 stutters per minute to 0.2 stutters per minute in about 20 hours of therapy over four months. (8)Two studies found a 40-70% reduction in stuttering 6-9 months after 5-20 hours of EMG therapy: Craig, Cleary, "Reduction of stuttering by young male stutterers using EMG feedback," Biofeedback and Self Regulation, 1982 September; 7(3): 241-55; Manschreck, Kalotkin, Jacobson, "Utility of electromyographic biological feedback in chronic stuttering: a clinical study with follow-up," Perception and Motor Skills 1980 October; 51(2): 535-40. (9) The "criteria for success" was less than 1.4% stuttered syllables, at a speaking rate of 3.5 syllables per second. At six months post- therapy 82% of subjects met the criteria; at twelve months, 89%; at 2 years, 92%. Reported by CAFET, Inc., 4208 Evergreen Lane, Suite 213, Annandale, VA 22003.