1Chapter 8 Temporal Processing in Children With Language Disorders
Scientists have attempted to understand the seemingly effortless process of language acquisition in infants for decades. Despite the acoustic complexity of speech input and apparent limited neurological processing resources of an immature neonatal brain, most infants master their native language in a few years. To accomplish this, the infant must extract from the continuous auditory signals in the environment meaningful segments that constitute phonemes, syllables, and words and determine how they combine into meaningful strings (Dehaene-Lambertz et al., 2006). The process proceeds predictably and effortlessly despite variability in language exposure or culture (Kuhl, 2000). This ease with which children acquire language and the uniformity across languages led Noam Chomsky in 1986 to propose that human infants must possess an innate neurological capacity to acquire language (Chomsky, 1986). The exact nature of this “language acquisition device” has been debated and researched ever since. Yet, as Patricia Kuhl states in a thorough review of the research on language acquisition mechanisms, “cracking the speech code is child’s play for human infants but [remains] an unsolved problem for adult theorists and our machines” (Kuhl, 2004). Even more perplexing, perhaps, is why a small proportion (6-7%) of children, without sensory, motor, or nonverbal cognitive decits, fail to develop normal language skills despite exposure to their native language (Tomblin, Records, & Zhang, 1996).