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D R Soderquist

Publications and source records attributed to D R Soderquist.

11 recordsLinked to original sources
PubMed1993

Auditory filter widths in children and adults.

Filter widths for six groups of subjects, adults and children ages 6, 7, 8, 9, and 10, were estimated using two different psychophysical approaches. Subjects participated in an experiment with a fixed signal level (psychophysical tuning curve procedure) and in an experiment having a fixed masker level (notched noise procedure). The psychophysical tuning curves were determined with 200-Hz-wide noise bands centered at 2.3, 2.6, 3.0, 3.4, and 3.6 kHz. The 200-ms, 3-kHz signal was fixed in level at 30 dB SPL. Notched noise thresholds were determined with notch widths of (delta f/f) 0.0, 0.2, and 0.4. The delta f was the distance, in hertz, from the center frequency, f, to the edge of symmetrically placed bands of noise. The bands of noise were fixed at 35-dB pressure spectrum level. Results revealed no significant differences between the children and the adults on measures of Q10, ERB, and K. The conclusion of the present study was that auditory filter widths from the ages of 6 to adult were not significantly different.

Acoustic Stimulation↗
PubMed1990

Auditory backward recognition masking: effect of interaural phase on masker efficacy.

The effect of interaural phase on pitch and lateralization recognition was examined. Tonal signals were followed by a variable interstimulus interval and an interference tone. Stimuli were presented in a binaural masking-level difference paradigm as a means of manipulating the perceptual location of the signal within the head. In separate tasks, subjects were required to recognize the pitch or location of the signal. The pitch-recognition task resulted in the expected increase in performance as the interstimulus interval increased. There was no effect of interaural phase on pitch-recognition performance. There was no significant effect of interstimulus interval on performance in location recognition. Subjects were proficient at recognizing location of the signal regardless of the interstimulus interval. The data suggest that a strict single-channel interpretation of the preperceptual storage model of backward auditory recognition is inadequate.

Adult↗
PubMed1984

The precedence effect: revisited.

The precedence effect, as investigated by Wallach et al. [Am. J. Psychol. 62, 324-336 (1949)] was studied in three experiments. Experiment I was a replication of the original work of Wallach et al. Although the first click pair appears to dominate the perception of the position of the lateral image, the effect of the first click pair does not appear to "offset" or "cancel" the effect of the second click pair in terms of producing a lateral image at midline. The data are consistent with Zurek's [J. Acoust. Soc. Am. 67, 952-964 (1980)] proposal that the binaural system is less sensitive to the interaural temporal difference of the second click pair. Experiment II indicated that the effect of the first click pair on lateral judgments still dominates that of the second click pair when the images are judged to be off midline. In all of these studies, the variability of the data is quite high. Experiment III showed that the first click pair also led to a larger change in masked thresholds (masking-level differences, MLDs) than does the second click pair. These data reconfirm the use of two-click stimuli for demonstrations of the precedence effect and they describe some of the limitations of the procedure and the generalities of the effect.

Acoustic Stimulation↗
PubMed1982

Transient complex and pure tone pitch changes by adaptation.

The effect of pitch adaptation by a complex stimulus was examined in two experiments. In experiment 1, a monaural complex tone pitch change was measured after ipsilateral or contralateral complex stimulus adaptation. While ipsilateral adaptation resulted in pitch changes away from the pitch of the adapting stimulus, no pitch occurred for contralateral adaptation. The precision of pitch matching was reduced by both ipsilateral and contralateral adaptation. Experiment 2 examined whether the complex tone pitch changes in experiment 1 could be accounted for by pitch changes induced in the pure tone components. Results indicated that changes induced in the pure tone components were too small to account for the complex tone shift magnitudes found in experiment 1. These results support a degree of independence of complex tone pitch from the pitches of the pure tone components. Results also supported pitch extractor specialization for a particular ear of stimulus presentation.

Adaptation, Physiological↗
PubMed1981

Backward, simultaneous, and forward masking as a function of signal delay and frequency.

Backward, simultaneous, and forward masking were investigated in 7 normal-hearing adults using a 1-kc/s sinusoid masker of 250 msec duration and 60 db SPL. 10-msec sinusoidal signals (probes) were varied in frequency (.4, .8, .9, .95, 1.05, 1.1, 1.2, 1.6 kc/s) and temporal location, delta t, prior to (-250, -150, -40, -20, -10, -2 msec re: masker onset), during (2, 10, 20, 40, 125, 250 msec re: masker onset), or following (2, 10, 20, 40, 125, 250 msec re: masker offset). The double random staircase psychophysical method (Cornsweet, 1962) was used in all conditions. Monotic thresholds were obtained for the backward and forward masking conditions. Dichotic and monotic thresholds were collected for the simultaneous condition. Results showed: (a) Backward masking. The greatest masking (up to 25 db) occurred between 0.0 and -40 msec when the signal probe was within +/- .2 cps of the masker. There was a linear decrease in masking as a function of delta t; masking effects extended to 250 msec. (b) Forward masking. The data revealed no masking beyond 125 msec delta t, an asymmetry in the masking pattern, relatively large threshold shifts (up to 33 db) when delta t was less than 40 msec and the signal was approximately +/- .2 kc/s within the masker. (c) Simultaneous masking. Overshoot occurred at onset and offset for both dichotic and monotic conditions; onset overshoot was larger in both conditions. The data revealed more forward masking than backward masking at equivalent absolute delta t values. Data were discussed in terms of cochlear vibration patterns and hypothesized central mechanisms.

Adult↗
PubMed1978

Adaptation of residue pitch.

Residue pitch was examined by means of adaptation. The monaural perceptibility of a residue pitch was measured before and after exposure to ipsilateral or contralateral adapatation stimuli of variable spectral composition. Several aspects of adaptation were investigated: pitch channel specificity, number of stimulus components necessary to adapt a residue channel, importance of temporal and spectral factors for adaptation, and the relation between pure-tone and residue pitch. It was found that there are residue-pitch channels specifically sensitive to the spectral region and ear of presentation of the stimulus. At least two harmonics were necessary to adapt a residue channel, and pitch channels were found to be insensitive to temporal factors. Residue and pure-tone pitch seemed to be extracted by different mechanisms, having independent channels. The data presented augment the understanding of pitch perception and suggest refinements for pitch-perception models.

Cues↗