Language and Theory of Mind: A Study of Deaf Children

Social cognition as a mediator of cognition and outcome among deaf and hearing people with schizophrenia

It has been suggested in the research literature that facial affect processing (FAP) and theory of mind (ToM) are both potential mediators of the well-established relationship between cognition and functional outcome among people with schizophrenia. The current project tests the mediating potency of these two domains of social cognition among deaf and hearing people with schizophrenia. Sixty-five people (34 deaf, 31 hearing) were assessed using measures of verbal and visual memory, attention, visual processing, FAP, and ToM. The results suggest that each domain of cognition, save vigilance, exerts an effect on functional outcome indirectly through its influence on social cognition. The patterns of mediation varied when the samples were broken down by hearing status and analyzed separately. Namely, the cognitive tasks directly involving linguistic ability (early visual processing [EVP] and word memory) were best mediated by social cognition for hearing subjects. For deaf subjects, the nonlinguistic cognitive tasks (e.g., visual-spatial memory-recall and copy [VSM-recall and VSM-copy]) were best mediated by social cognition. While FAP and ToM were equally effective as mediators for hearing subjects, FAP was a more potent mediator than ToM for deaf subjects. This study extends prior work in the area of social cognition and schizophrenia and indicates that the development of cognitive rehabilitation strategies should include not only interventions targeting specific cognitive abilities, such as attention and memory, but should include an emphasis on social-cognitive domains, including FAP and ToM. Further, deaf and hearing subjects may benefit from interventions addressing aspects of cognition that support linguistic ability, especially as they relate to social cognition.

Theory of mind and language in children with cochlear implants

Thirty children with cochlear implants (CI children), age range 3-12 years, and 30 children with normal hearing (NH children), age range 4-6 years, were tested on theory of mind and language measures. The CI children showed little to no delay on either theory of mind, relative to the NH children, or spoken language, relative to hearing norms. The CI children showed a slightly atypical sequence of acquisition of theory of mind concepts. The CI children's theory of mind performance was associated with general syntactic proficiency more than measures of complement syntax, and with time since implantation more than age at implantation. Results suggest that cochlear implantation can benefit spoken language ability, which may then benefit theory of mind, perhaps by increasing access to mental state language.

Visual working memory capacity and proactive interference

BACKGROUND

Visual working memory capacity is extremely limited and appears to be relatively immune to practice effects or the use of explicit strategies. The recent discovery that visual working memory tasks, like verbal working memory tasks, are subject to proactive interference, coupled with the fact that typical visual working memory tasks are particularly conducive to proactive interference, suggests that visual working memory capacity may be systematically under-estimated.

METHODOLOGY/PRINCIPAL FINDINGS

Working memory capacity was probed behaviorally in adult humans both in laboratory settings and via the Internet. Several experiments show that although the effect of proactive interference on visual working memory is significant and can last over several trials, it only changes the capacity estimate by about 15%.

CONCLUSIONS/SIGNIFICANCE

This study further confirms the sharp limitations on visual working memory capacity, both in absolute terms and relative to verbal working memory. It is suggested that future research take these limitations into account in understanding differences across a variety of tasks between human adults, prelinguistic infants and nonlinguistic animals.