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served (e.g., Wightman and Kistler, 2005; Nishi et al., 2010). analysis is to measure the extent to which children rely on
The pronounced difliculties experienced by younger school- acoustic voice ditferences between talkers to segregate target
age children are somewhat perplexing in light of data i.ndi- from masker speech (e.g., Flaherty et al., 2018; Leibold et aL,
cating that the peripheral encoding of sound matures early 2018). For example, striking effects have been found between
inlife. lt has been posited that these age effects reflect an im- conditions in which the target and masker speech are pro-
mature ability to recognize degraded speech (e.g., Eisenberg duced by talkers that difier in sex (e.g., a female target talker
et al., 2000; Buss et aL, 2017). It has also been suggested that and a two-male-talker masker) and conditions in which tar-
children’s immature working memory skills also play a role get and masker speech are produced by talkers of the same
in their speech-in-noise clifliculties (McCreery et al., 2017). sex (e.g., a male target talker and a two-rnale-talker masker).
Dramatic improvements in speech intelligibility, as much as
lvlaturauan ”fA“dm°"y scene Analyais 20 percentage points, have been reported in the literature
chi-ldre“ "5 3‘ 3 dlsadvmmge mlafivg (0 adults when 115' for sex-mismatched relative to sex-matched conditions (e.g.,
tening to speech in competing noise, but the child/adult Half“. and Frewnm) 2008)‘
difference is considerably larger when the maskers are also
composed of speech. Hall et al. (2002) compared word rec- School-age (Wightmau and KiSi18l,2005; 1315015 Gt 31-» 2013)
ognition for children (5-10 years) and adults tested in each and 30-mimth-old (Newman and Morini. 2017) Chfldffifl
of two maskersz 1-wise fijgfl-Ed (9 haw me “me pow“ spec. also show a robust benefit of a target/masker sex mismatch,
trum as speech (speech-shaped noise; see Multimedia File 1 but l-“fan” Y°““3" than 15 mmlths 0’. 389 d0 50‘ (Newman
at acousticstoday.org/leibold-media) and competing speech and Mflfillix 2017; 14815015 CT 51-: 2018)- Leibold 9‘ 5-L (2013),
Composed ofmn pgople taking 31 the same time (See Mum. for example, measured speech detection in a two-talker
media File 2 at acousticstoday.org/leibold-media), On aver- m35k5T 5-“ 7' (0 13‘m°Dd1'°ld infants and 1'-U adum» Ad‘-1115
agg children mqujred 3 3 cu; more {Womble SNR mlafive performed better when the target word and masker speech
to adults to achieve a comparable performance in the noise were mismamhed in SEX than "hm me)’ We“ matched‘ 1“
masker. This disadvantage increased to 8 dB in the two-talker Sh“? Contrast. infants Verfmmed sim’-lull’ 1“ 55x'ma‘Ch5d
masker. In addition to the relatively large child/adult diifer- and sax-mismatched wnditions The overall Pattern of re-
ences observed in the two-talker masker relative to the noise mks Obsewed “"055 smdl-55 Suggest l-ha‘ the ‘bum’ t° like
masker, the ability to recognize masked speech develops at advantage of acoustic voice dilferences between male and
diiferent rates for these two types of maskers (e.g., Corbin et ftmale ‘ill-k5“ “(lull-"5 e"P"l‘“C“-‘ with dl-E5155‘ “]k"5 be‘
al. 2016). Although adult-like speech recognition in compet- f01'3 l-ll? 3bi1itY emerges 50m¢mT1€ belwem 1'-U-f3|1CY and the
ing noise emerges by 9-10 years of age (e.g.. Wightrnan and P15551100] Yea-'5'
Kistler, 2005; Nlshi 9‘ 31» 2010)- 5P°ed_" Iecognmotl perfm_' Although children as young as 30 months of age benefit from
mance in a two-talker speech masker is not adult-like until . . .
_ _ _ a target/masker sex mismatch, the ability to use more subtle
13-14 years of age (Corbtn et aL, 2016). This prolonged time . . .
f d 1 be 1 art] d and/or less redundant acoustic voice diiferences may take
Fourse 0 we opmmt ap_Pears (0 ab ea“ P _ Y ue_ to longer to develop. Flaherty et al. (2018) tested this hypoth-
immature sound segregation and selective attention skills. . b . . h h hfld 5 15 d d U1
Reco 'tion of s eech roduced b the teacher is likel to ems Y g W st H C [en ( - yea”) an 2 ls
_  P P Y _ I Y benefited from a diflerence in voice pitch (i.e., fundamen-
be limited more by speech produced by other children iii the _
_ _ A tal frequency. F0) between target words and a two-talker
classroom than by noise produced by the proiector (see Fi.g- . . . .
_ _ _ 1 speech masker, holding other voice characteristics constant.
ure 1). The term irfiirrrmtmnal masking is often used to refer AS mviousl ohserved for adults (5 Darwin 6‘ aL 2003)
to this phenomenon (e.g. Brungart 2005). P Y. ig” ’
’ ’ adults and children older than 13 years of age performed
An important goal for researchers who study auditory de- substantially better when the target and masker speech dif-
velopment is to characterize the factors that both facilitate fered in F0 than when the F0 of the target and masker speech
and limit chi.ldren’s ability to perform auditory scene analysis was matched. This improvement was observed even for the
(e.g., Newman et aL, 2015; Calandruccio et al., 2016). For lis- smallest target/masker F0 diiference of three semitones. Ln
teners of allages, the perceptual sirnilaritybetweentarget and sharp contrast, younger children (<7 years) did not benefit
masker speech afl’ects performance in that greater masking is from even the most extreme F0 difference of nine semitones.
associated with greater perceptual similarity. A common ap- Moreover. although 8- 12 year olds benefitted from the largest
proach to understanding the development of auditory scene F0 diflerence, they generally failed to take adwntage of more
Spring 2019 | An:nulI:|I:l Thday | an












































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