<P> Infants as young as 1 month perceive some speech sounds as speech categories ( they display categorical perception of speech ) . For example , the sounds / b / and / p / differ in the amount of breathiness that follows the opening of the lips . Using a computer generated continuum in breathiness between / b / and / p / , Eimas et al. ( 1971 ) showed that English - learning infants paid more attention to differences near the boundary between / b / and / p / than to equal - sized differences within the / b / - category or within the / p / - category . Their measure , monitoring infant sucking - rate , became a major experimental method for studying infant speech perception . </P>
<P> Infants as young as 1 month perceive some speech sounds as speech categories ( they display categorical perception of speech ) . For example , the sounds / b / and / p / differ in the amount of breathiness that follows the opening of the lips . Using a computer generated continuum in breathiness between / b / and / p / , Eimas et al. ( 1971 ) showed that English - learning infants paid more attention to differences near the boundary between / b / and / p / than to equal - sized differences within the / b / - category or within the / p / - category . Their measure , monitoring infant sucking - rate , became a major experimental method for studying infant speech perception . </P>
when do babies become able to distinguish different speech sounds
when do babies become able to distinguish different speech sounds
as young as 1 month
as young as 1 month