Document Detail

Forward masking among infant and adult listeners.
MedLine Citation:
PMID:  10212425     Owner:  NLM     Status:  MEDLINE    
Psychophysical forward-masked thresholds were estimated for 3- and 6-month-old infants and for adults. Listeners detected a repeated 1000-Hz probe, with 16-ms rise time, no steady-state duration, and 16-ms fall time. Unmasked thresholds were determined for one group of listeners who were trained to respond when they heard the probe but not at other times. In the masking conditions, each tone burst was preceded by a 100-ms broadband noise masker at 65 dB SPL. Listeners were trained to respond when they heard the probe and masker, but not when they heard the masker alone. The masker-probe interval, delta t, was either 5, 10, 25, or 200 ms. Four groups of subjects listened in the masked conditions, each at one value of delta t. Each listener attempted to complete a block of 32 trials including four probe levels chosen to span the range of expected thresholds. "Group" thresholds, based on average psychometric functions, as well as thresholds for individual listeners, were estimated. Both group and individual thresholds declined with delta t, as expected, for both infants and adults. Infants' masked thresholds were higher than those of adults, and comparison of masked to unmasked thresholds suggested that infants demonstrate more forward masking than adults, particularly at short delta t. Forward masking appeared to have greater effects on 3-month-olds' detection than on either 6-month-olds' or adults'. Compared to adults, 6-month-olds demonstrated more forward masking only for delta t of 5 ms. Thus, susceptibility to forward masking may be nearly mature by 6 months of age.
L A Werner
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Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  The Journal of the Acoustical Society of America     Volume:  105     ISSN:  0001-4966     ISO Abbreviation:  J. Acoust. Soc. Am.     Publication Date:  1999 Apr 
Date Detail:
Created Date:  1999-07-16     Completed Date:  1999-07-16     Revised Date:  2014-05-09    
Medline Journal Info:
Nlm Unique ID:  7503051     Medline TA:  J Acoust Soc Am     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  2445-53     Citation Subset:  IM    
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MeSH Terms
Auditory Perception / physiology*
Auditory Threshold / physiology
Perceptual Masking*
Grant Support

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

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