Frequency-Modulation (FM) Technology as a Method for Improving Speech Perception in Noise for Individuals with Multiple Sclerosis

Almost half of the population with multiple sclerosis (MS) complains of difficulty hearing, despite having essentially normal pure-tone thresholds. The purpose of the present investigation was to evaluate the effects of frequency-modulation (FM) technology utilization on speech perception in noise for adults with and without MS. Sentence material was presented at a constant level of 65 dBA L_eq from a loudspeaker located at 0°azimuth. The microphone of the FM transmitter was placed 7.5 cm from this loudspeaker. Multitalker babble was presented from four loudspeakers positioned at 45°, 135°, 225°, and 315° azimuths. The starting presentation level for the babble was 55 dBA L_eq. The level of the noise was increased systematically in 1 dB steps until the subject obtained 0% key words correct on the IEEE (Institute for Electrical and Electronic Engineers) sentences. Test results revealed significant differences between the unaided and aided conditions at several signal-to-noise ratios.

Key Words

FM technology - hearing - multiple sclerosis - speech perception