Some issues in infant speech perception: do the means justify the ends.

A major focus of research on language acquisition in infancy involves experimental studies of the infant's ability to discriminate various kinds of speech or speech-like stimuli. This research has demonstrated that infants are sensitive to many fine-grained differences in the acoustic properties of speech utterances. Furthermore, these empirical findings have led investigators to theorize about how the infants internally process and represent speech stimuli. This paper examines one particular experimental protocol frequently used in these experiments: the Head-Turn Preference Procedure. It will be shown that this procedure is methodologically flawed and the theoretical conclusions drawn from its results are not adequately warranted.