Journal article
Combination tones and unmasking
Hearing research, Vol.2(3), pp.357-368
1980
DOI: 10.1016/0378-5955(80)90070-2
PMID: 7410240
Abstract
Some important relationships between two auditory nonlinearities, unmasking and combination tone (CT) production, are described. An example of unmasking is provided by using a forward-masking paradigm where a baseline is first obtained by determining the threshold of a 2000 Hz signal preceded by a 2000 Hz masker. When a second tone (the suppressor) is then added concurrently with the masker, the signal can be easier to hear. At a suppressor level of 80 dB SPL, this unmasking occurs for suppressor frequencies around 2300 Hz. At a suppressor level of 55 dB SPL, the unmasking effect occurs at suppressor frequencies closer to the masker frequency. An example of CT production is provided by presenting two sinusoids
(ƒ
1
and ƒ
2)
as maskers in a forward-masking experiment. The threshold of the 2000 Hz signal is shown to decrease as
ƒ
2/ƒ
1
is increased keeping
2ƒ
1 − ƒ
2 = 2000
Hz
. This is consistent with the notion that the magnitude of the CR decreases as
ƒ
2/ƒ
1
increases. We then provide evidence that CTs can produce unmasking effects similar to acoustic tones. Again a baseline was determined with a 2000 Hz signal and masker
(ƒ
1)
. Two higher-frequency sinusoids
(ƒ
2
and ƒ
3)
were added simultaneously to the masker, neither of which produced unmasking when presented individually. When
2ƒ
2 – ƒ
3
or ƒ
3 – ƒ
2
was approximately 2300 Hz, unmasking was observed. Next we explored
2ƒ
2 – ƒ
3
unmasking as a function of
ƒ
3/ƒ
2
, keeping
2ƒ
2 – ƒ
3
frequency fixed at 2300 Hz. As
ƒ
3/ƒ
2
increases, the magnitude of the unmasking decreases. These CT unmasking effects suggest that the generation of CTs must be at the same site or peripheral to the site of suppression.
Details
- Title: Subtitle
- Combination tones and unmasking
- Creators
- Richard S Tyler - MRC Institute of Hearing Research, University of Nottingham, Nottingham NG7 2UH, U.K
- Resource Type
- Journal article
- Publication Details
- Hearing research, Vol.2(3), pp.357-368
- DOI
- 10.1016/0378-5955(80)90070-2
- PMID
- 7410240
- NLM abbreviation
- Hear Res
- ISSN
- 0378-5955
- eISSN
- 1878-5891
- Publisher
- Elsevier B.V
- Language
- English
- Date published
- 1980
- Academic Unit
- Communication Sciences and Disorders; Otolaryngology
- Record Identifier
- 9984002597802771
Metrics
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