Vibrotactile Forward Masking: Effects of Masker Duration and Sensation Level

AbstractThe symptom of tinnitus is likely shared by several underlying pathologies. It is funda-mental to the investigation and treatment of tinnitus to be able to reliably quantify different types of tinnitus. In one experi-ment we required patients to increase the level of a broadband noise until it just masked their tinnitus. Regardless of where in the head they perceive their tinnitus, in most patients the minimum level (in sound pressure level or sensation level) required to mask the tinnitus is similar in both ears. In a few other patients, the tinnitus cannot be masked or requires high levels in the contra-lateral ear. We have found this masking procedure valuable in measuring tinnitus following the administration of tocainide. In some patients the tocainide seemed to reduce the magnitude of the tinnitus (required lower masker levels to mask the tinnitus) whereas in others there was some evidence that the tinnitus got worse (higher masker levels were required). In another experiment, we quantified tinnitus percep-tion following the termination of a masker. Several different patterns were evident. After the termination of the masker, the tinnitus either (a) returned to normal immediately, (b) returned immediately but was at a softer loudness, (c) was absent for a time before gradually returning to normal, (d) was absent for a time before abruptly returning to normal, or (e) was louder than normal before gradually returning to normal. Increasing masker duration and masker level prolonged the effects.

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Children's Performance on a Binaural Fusion Task

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.2404.520 ◽

1981 ◽

Vol 24 (4) ◽

pp. 520-525 ◽

Cited By ~ 2

Author(s):

Bruce L. Plakke ◽

Daniel J. Orchik ◽

Daniel S. Beasley

Keyword(s):

Enhancement Effect ◽

Sensation Level ◽

Large Measure ◽

Filter Bandwidth ◽

Research Results ◽

Presentation Modes ◽

Monosyllabic Words ◽

Better Than

Binaural auditory fusion of 108 children (4, 6, and 8 years old) was studied using three lists of monosyllabic words (WIPI) presented at two sensation levels (30 and 40 dB). The words were processed to produce three bandwidth conditions (100, 300, 600 Hz) and were administered via three presentation modes (binaural fusion 1, diotic, binaural fusion 2). Results showed improved discrimination scores with increasing age, sensation level, and filter bandwidth. Diotic scores were better than binaural fusion scores for the narrower bandwidth conditions, but the diotic enhancement effect was seriously compromised in the widest bandwidth (600 Hz) condition. The results confirmed the contention that prior research results were equivocal due, in large measure, to procedural variability. Methods for reducing such variability and enhancing the clinical viability of binaural fusion tasks are suggested.

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The Effects of Variable-Interval and Fixed-Interval Signal Presentation Schedules on the Auditory Evoked Response

Journal of Speech and Hearing Research ◽

10.1044/jshr.1201.199 ◽

1969 ◽

Vol 12 (1) ◽

pp. 199-209 ◽

Cited By ~ 12

Author(s):

David A. Nelson ◽

Frank M. Lassman ◽

Richard L. Hoel

Keyword(s):

Variable Interval ◽

Tone Burst ◽

Signal Amplitude ◽

Fixed Interval ◽

Interval Schedule ◽

Sensation Level ◽

Fixed Interval Schedule ◽

Auditory Evoked Responses ◽

Auditory Evoked Response ◽

Signal Presentation

Averaged auditory evoked responses to 1000-Hz 20-msec tone bursts were obtained from normal-hearing adults under two different intersignal interval schedules: (1) a fixed-interval schedule with 2-sec intersignal intervals, and (2) a variable-interval schedule of intersignal intervals ranging randomly from 1.0 sec to 4.5 sec with a mean of 2 sec. Peak-to-peak amplitudes (N 1 — P 2 ) as well as latencies of components P 1 , N 1 , P 2 , and N 2 were compared under the two different conditions of intersignal interval. No consistent or significant differences between variable- and fixed-interval schedules were found in the averaged responses to signals of either 20 dB SL or 50 dB SL. Neither were there significant schedule differences when 35 or 70 epochs were averaged per response. There were, however, significant effects due to signal amplitude and to the number of epochs averaged per response. Response amplitude increased and response latency decreased with sensation level of the tone burst.

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Temporal-Gap Detection by Cochlear Prosthesis Users

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.3204.849 ◽

1989 ◽

Vol 32 (4) ◽

pp. 849-856 ◽

Cited By ~ 12

Author(s):

John P. Preece ◽

Richard S. Tyler

Keyword(s):

Magnitude Estimation ◽

Stimulus Level ◽

Electrode Placement ◽

Frequency Effect ◽

Gap Detection ◽

Cochlear Prosthesis ◽

Sensation Level

Minimum-detectable gaps for sinusoidal stimuli were measured for three users of a multi electrode cochlear prosthesis as functions of stimulus level, frequency, and electrode place within the cochlea. Stimulus level was scaled by sensation level and by growth-of-loudness functions generated for each condition by direct magnitude estimation. Minimum-detectable gaps decreased with increase in either sensation level or loudness, up to a plateau. When compared at equal sensation levels, the minimum-detectable gaps decreased with frequency increases. The frequency effect on minimum-detectable gaps is reduced if the data are considered at equal loudness. Comparison across place of stimulation within the cochlea showed minimum-detectable gaps to be shorter for more basal electrode placement at low stimulus levels. No differences in minimum-detectable gap as a function of place were found at higher stimulus levels.

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