This essay focuses on rudimentary language skills. Language ability is a hallmark human characteristic, and although there are rudimentary

rudimentary language skills

Have you ever learned a second language? How easy was it for you to speak the new language flawlessly? Likely, the success of your experiences has depended on how old you were when you started to learn the new language. How people go about acquiring languages is the question that has attracted the vast majority of research on sensitive periods in humans.

Language ability is a hallmark human characteristic, and although there are rudimentary language skills in some other species (Seyfarth, Cheney, & Marler, 1980), no other species is as dependent -on language skills or has as complex a language system as humans. It is easy to imagine how language skills provided a survival advantage to humans. Being able to describe to others where the dangers are, to coordinate each other’s behaviors to increase the success of a hunt, to discover and share the precise social dynamics

that are occurring among

your allies and competitors, and to say the right things so that you can attract a mate-all of these advantages suggest that those humans who were able to communicate most effectively were more likely to produce surviving offspring than those who were not. Because language skills confer such an obvious evolutionary advantage, there should be evidence of a sensitive period for language acquisition. One source of evidence for such a sensitive period is with rct:spect to people’s abilities to discriminate among different sounds. Humans are capable of producing, recognizing, and using approximately 150 phonemes (units of sound) in communication; however, no language uses more than 70 of them (Brown, 1991). This means that many phonemes that are used in various languages around the world are not used in other languages. Interestingly, people are

not able to discriminate easily

between some phonemes that are not in their own language. For example, the Japanese 164 CHAPTER 5 � DEVELOPMENT AND SOCIALIZATION language does not have separate phonemes for the sounds “la” and “ra.” Likewise, the Japanese language does not have a phoneme for “va,” although it does have a phoneme for the closely related sound of”ba.” Consequently, an adult who was exposed only to the Japanese language cannot perceive the differences between “la”s and “ra”s, or between “ba”s and “va”s-phonemes that sound obviously different to English speakers. To native Japanese-speaking

adults who never learned English as a child, the words “rubber” and “lover” sound the same, a fact that has surely led to some embarrassing cross-cultural misunderstandings! So, how do English speakers learn to distinguish between sounds that sound the same to Japanese speakers? Research suggests that young infants can discriminate among all the phonemes that humans are able to produce. We come into this world able to recognize all kinds of different sounds. As we are exposed to a language, we begin to categorize sounds in ways that are used by that language. And this begins early in life-very early. Within the first year, infants already begin to lose the ability. This is  to distinguish between closely related sounds that are not in their own language. For example, as Figure 5.2 shows, native