Comparative Bekesy Typing with Broad and Modulated Narrow-Band Noise

1969 ◽  
Vol 12 (4) ◽  
pp. 840-846
Author(s):  
Charles T. Grimes ◽  
Alan S. Feldman

This study explored the effectiveness of modulated narrow-band noise as a masking source for sweep-frequency Bekesy audiometry. Five sophisticated normal-hearing subjects traced Bekesy audiometry thresholds for pulsed and continuous tone with no masking and under three conditions of contralateral masking: (1) white noise, (2) modulated narrow-band noise with a constant band-width of ±150 Hz, and (3) modulated narrow-band noise with a band-width of ±300 Hz. Results indicated that the continuous tone tracing obtained under the second condition separated from the pulsed tracing supportive of a Type II tracing. With the third condition, pulsed-continuous differences were somewhat smaller. Under the first condition, the difference between pulsed and continuous tracings was not apparent. When two unsophisticated subjects were tested with the modified band-width noise, results indicated extreme variation between pulsed and continuous tracings. We concluded that the masking effect of a constant band-width modulated narrow-band noise is about the same as that of white noise for a pulsed tone tracing. However, the use of a modulated narrow-band noise masking source may cause false Type II Bekesy audiograms due to the greater masking effect on a continuous tone threshold.

1990 ◽  
Vol 47 (1-2) ◽  
pp. 175-181 ◽  
Author(s):  
Zhang Weiping ◽  
Richard J Salvi ◽  
Nicholas Powers ◽  
Wu Jinghui

1977 ◽  
Vol 61 (S1) ◽  
pp. S29-S29 ◽  
Author(s):  
S. E. Fahrbach ◽  
J. C. Saunders ◽  
G. R. Bock

1965 ◽  
Vol 8 (3) ◽  
pp. 253-261
Author(s):  
Zahrl G. Schoeny ◽  
Cornelius P. Goetzinger ◽  
Albert W. Knox

Twenty subjects with normal hearing and 20 subjects with sensori-neural hearing loss were examined relative to the effects of wide- and narrow-band white noise delivered by bone conduction at the forehead; differences between thresholds with interrupted- and continuous-tone presentation under the conditions of quiet, wide-band noise, narrow-band noise; the difference between threshold shifts at 1 000 and 2 000 cps when the SAL masking technique is used; and differences between SAL and conventional bone-conduction thresholds at 1 000 or 2 000 cps. Narrow-band noise produced less shift than wide-band noise under all conditions Differences between interrupted- and continuous-tone presentation yielded better thresholds. Shifts at 1 000 cps and 2 000 cps were significantly different, with the shift at 1 000 cps being greater.


1999 ◽  
Vol 39 (13) ◽  
pp. 2191-2203 ◽  
Author(s):  
Mark W. Cannon ◽  
Greg J. Reese ◽  
Steven C. Fullenkamp

2002 ◽  
Vol 12 (9) ◽  
pp. 85-86
Author(s):  
R. C. Rai ◽  
V. A. Bondarenko ◽  
J. W. Brill

We have searched for narrow-band-noise (NBN) modulations of the infrared transmission in blue bronze, using tunable diode lasers. No modulations were observed, giving an upper limits for NBN changes in the absorption coefficient of $\Delta \alpha_{NBN} < 0.3 $ / cm ($\approx \alpha/2000$). The implication of these results on proposed CDW properties and NBN mechanisms are discussed.


Perception ◽  
10.1068/p3338 ◽  
2002 ◽  
Vol 31 (7) ◽  
pp. 855-873 ◽  
Author(s):  
Helen J Simon ◽  
Pierre L Divenyi ◽  
Al Lotze

The effects of varying interaural time delay (ITD) and interaural intensity difference (IID) were measured in normal-hearing sighted and congenitally blind subjects as a function of eleven frequencies and at sound pressure levels of 70 and 90 dB, and at a sensation level of 25 dB (sensation level refers to the pressure level of the sound above its threshold for the individual subject). Using an ‘acoustic’ pointing paradigm, the subject varied the IID of a 500 Hz narrow-band (100 Hz) noise (the ‘pointer’) to coincide with the apparent lateral position of a ‘target’ ITD stimulus. ITDs of 0, ±200, and ±400 μs were obtained through total waveform delays of narrow-band noise, including envelope and fine structure. For both groups, the results of this experiment confirm the traditional view of binaural hearing for like stimuli: non-zero ITDs produce little perceived lateral displacement away from 0 IID at frequencies above 1250 Hz. To the extent that greater magnitude of lateralization for a given ITD, presentation level, and center frequency can be equated with superior localization abilities, blind listeners appear at least comparable and even somewhat better than sighted subjects, especially when attending to signals in the periphery. The present findings suggest that blind listeners are fully able to utilize the cues for spatial hearing, and that vision is not a mandatory prerequisite for the calibration of human spatial hearing.


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