Childhood hearing loss presents challenges to language development, especially spoken language. In this article, we review existing literature on deaf and hard-of-hearing (DHH) children's patterns and trajectories of language as well as development of theory of mind and literacy. Individual trajectories vary significantly, reflecting access to early identification/intervention, advanced technologies (e.g., cochlear implants), and perceptually accessible language models. DHH children develop sign language in a similar manner as hearing children develop spoken language, provided they are in a language-rich environment. This occurs naturally for DHH children of deaf parents, who constitute 5% of the deaf population. For DHH children of hearing parents, sign language development depends on the age that they are exposed to a perceptually accessible 1st language as well as the richness of input. Most DHH children are born to hearing families who have spoken language as a goal, and such development is now feasible for many children. Some DHH children develop spoken language in bilingual (sign-spoken language) contexts. For the majority of DHH children, spoken language development occurs in either auditory-only contexts or with sign supports. Although developmental trajectories of DHH children with hearing parents have improved with early identification and appropriate interventions, the majority of children are still delayed compared with hearing children. These DHH children show particular weaknesses in the development of grammar. Language deficits and differences have cascading effects in language-related areas of development, such as theory of mind and literacy development.

Language skills were investigated in a multicultural sample of 13 prelingually deaf children (11 profoundly deaf from birth) who received cochlear implants between 14 and 38 months of age; average duration of implant use was 49 months. Individual postimplant language skills ranged from extremely delayed to age appropriate. On average, skills varied across domains: on vocabulary, several children functioned in the average range compared with hearing peers, but all were below that range on a test emphasizing syntax (CELF-P). Children with preimplant hearing experience had the highest scores on all language measures. Excluding these children, age of implantation (range 14 to 27 months) associated inversely and significantly with CELF-P scores, even when nonverbal IQ was controlled. Qualitative analyses indicated higher child language achievement associated with parents' reports of lengthy, in-depth processes to decide about cochlear implantation. Such reports may indicate high levels of ongoing parent involvement with child and programming.

This article presents a descriptive, longitudinal study of maternal use of communicative strategies to accommodate and direct infant visual attention. The two questions that guided our research were whether maternal use of particular attention-related strategies changed as the child developed from 9 to 18 months of age and whether the mother's ability to make appropriate modifications in strategy use was disrupted when she was using a new mode of communication. Four groups of mother-infant dyads were included: deaf mothers with deaf children (Dd), hearing mothers with deaf children (Hd), deaf mothers with hearing children (Dh), and hearing mothers with hearing children (Hh) (n = 77). When the infants were 9, 12, and 18 months old, they were videotaped while they engaged in free play with their mothers. Using a time-sampling technique, videotapes were coded to determine the frequency with which mothers used specific attention-related strategies. Our findings showed group differences in the attention-related strategies used by deaf and hearing mothers. These group differences were consistent with the hypothesis that while mothers appeared to be sensitive to and tried to accommodate their children's communication needs, the mothers may have been limited by their own communicative experiences. With regard to changes in mothers' use of attention-related strategies over time, our hypothesis of a developmental transition in the chosen strategies was only partially supported. Attention strategies related to language did evidence a pattern of developmental progression; however, maternal use of strategies that directed the children's visual focus to an object or a social partner did not show any such trend. Overall, the patterns indicated in the data from this study suggest that bidirectional influences were operating to some degree in each of the four groups. Among mothers whose hearing status differs from their children, the use of certain attention-related strategies might need to be taught, particularly the use of specific strategies that may scaffold deaf infants' developing abilities to alternate attention between objects and persons.

Word-learning skills of 19 deaf/hard-of-hearing preschoolers were assessed by observing their ability to learn new words in two contexts. The first context required the use of a novel mapping strategy (i.e., making the inference that a novel word refers to a novel object) to learn the new words. The second context assessed the ability to learn new words after minimal exposure when reference was explicitly established. The children displayed three levels of word-learning skills. Eleven children learned words in both contexts. Five were able to learn new words rapidly only when reference was explicitly established. Two children did not learn new words rapidly in either context. The latter seven children were followed longitudinally. All children eventually acquired the ability to learn new words in both contexts. The deaf children's word-learning abilities were related to the size of their vocabularies. The present study suggests that word-learning strategies are acquired even when children are severely delayed in their language development and they learn language in an atypical environment.

Deaf and hard-of-hearing (DHH) children's ability to rapidly learn novel words through direct reference and through novel mapping (i.e., inferring that a novel word refers to a novel object) was examined. Ninety-eight DHH children, ranging from 27 to 82 months old, drawn from 12 schools in five states participated. In two tasks that differed in how reference was established, word-learning abilities were measured by children's ability to learn novel words after only three exposures. Three levels of word-learning abilities were identified. Twelve children did not rapidly learn novel words. Thirty-six children learned novel words rapidly but only in the direct reference task. Forty-nine children learned novel words rapidly in both direct reference and novel mapping tasks. These levels of word-learning abilities were evident in children who were in oral-only and in signing environments, in children with cochlear implants, and in deaf children of deaf parents. Children's word-learning abilities were more strongly correlated to lexicon size than age, and this relation was similar for children in these different language-learning environments. Acquisition of these word-learning abilities seems based on linguistic mechanisms that are available to children in a wide range of linguistic environments. In addition, the word-learning tasks offer a promising dynamic assessment tool.