Relationships between word knowledge and visual speech perception. I. Subjective estimates of word age of acquisition

Abstract

In individuals with normal hearing, words estimated to be learned earlier are recognized more rapidly than words estimated to be learned later. To investigate how word knowledge is related to lipreading proficiency, word age-of-acquisition (AOA) estimates were obtained from 50 hearing (H) and 50 deaf (D) (80-dB HL pure-tone average or greater hearing losses acquired before the age of 48 months) adults. Participants judged AOA for the 175 words in Form M of the Peabody Picture Vocabulary Test-Revised using an 11-point scale, and responded whether the words were acquired through speech, sign language, or orthography. The two groups differed in when (mean AOA: H = 8.9 years, D = 10.6 years) and how (H=69% speech and 31% orthography; D=38% speech, 45% orthography, and 17% sign language) words were judged to be acquired. However, item analyses revealed that the relative acquisition order was essentially identical across groups (r=0.965). Interestingly, within the deaf group, better lipreaders estimated that more words had been learned through speech than orthography. An implication of these results is that learning words primarily through orthography does not support highly accurate spoken language processing. [Work supported by NIH Grant No. DC00695.]