Symposium: Hardware and software

The five papers presented in this session covered a very wide range of topics from EMG biofeedback training to the timing of events under the control of multiprogrammed real-time systems. The first paper by Pope and Gersten describes a computer-based system for response-contingent EMG biofeedback-assisted relaxation training. The paper describes the basic shaping procedure for the relaxation response, the hardware (a 24K Nova 2/10), and the operation of the shaping program. I feel that the primary audience for this paper will be individuals who are working in the field of biofeedback and are interested in developing computer based systems for their own research and clinical work. The next two papers, plus others given at a previous meeting (e.g., Cohen & Massaro, 1976; Poltrock & Mathews, 1976), should provide the reader with a reasonably complete introduction to computer-based systems for the generation and presentation of auditory stimuli. The paper by Knight is a very nice tutorial presentation of the logic and basic hardware and software requirements for the manipulation of digitized speech. Knight focuses on the problems of using a small computer (4K of memory) to perform such experiments, but I feel that his discussion is applicable to any size system. The presentation by Gillman, Wilson, Morse, and Kent! describes a complete system for the synthesis of speech and non speech stimuli, the recording of digitized waveforms, and the preparation of stimulus sequences for experimental use. The system uses Klatt's (1977) digital speech synthesizer for the by-art generation of speech stimuli. The system is written in FORTRAN IV, and its authors claim that it is portable. However, the hardware requirements are nontrivial. The system requires a fast 32K machine with a large amount of disk shortage and analog-to-digital and digital-to-analog converters. I have some reservations about the claim of portability, but this system represents an important contribution even if this claim is not true. Study of the write-ups, user manuals, and code (available from the authors) would