ABSTRACT
There has been a long-standing interest by researchers and theorists in the development of language. This interest has led to the invention or adaptation of instruments and methodologies that enable the study of early language development, such as various habituation, modeling, and other behavioral techniques; observational and recording techniques; transcription and coding techniques for language samples; and a variety of standardized and nonstandardized language assessment instruments. Although these instruments and methodologies are frequently used to obtain behavioral measures of language acquisition, other techniques involving physiological processes are also becoming more frequent and, indeed, have been shown to provide sometimes different and complementary information than that yielded by behavioral measures.
