Bridging Disciplinary Boundaries (January 11 - 14, 2007)

Deaf people with serious mental illness experience long-term institutionalization, disproportionately so in relation to their hearing counterparts. Few mental health systems are designed for the special needs of deaf people. Also, empirical support is lacking for the efficacy and effectiveness of standard psychosocial and pharmacological interventions with this population. For example, just sixteen empirical investigations of deaf people with schizophrenia have been published since 1929. It is therefore timely and important to advance research on the extent to which deafness exacerbates or mediates functional limitations associated with schizophrenia. This study addressed the following questions: (1) What is the relationship between symptoms and functional outcome among deaf and hearing people with schizophrenia (referred to as PWS hereafter)? (2) Does neurocognitive and social-cognitive ability predict levels of functional outcome among deaf and hearing PWS? Methods: The sample consists of sixty-five PWS (34 deaf, 31 hearing), recruited from a large psychosocial rehabilitation agency. The deaf and hearing subjects were similar with regards to key demographic variables. All subjects were assessed using established measures of memory, attention, and visual processing (i.e., neurocognition). In addition, social-cognition was evaluated via a test of the ability to decode facial affect (i.e., facial affect processing) and the ability to infer another person's intentions (i.e., theory of mind). Functional outcome was regressed on symptom profiles and each of the cognitive variables. Functional outcome was operationalized by a measure that assesses adaptive behaviors that influence community living (e.g., response to stress and anxiety). Results: In addition to basic comparative findings, key results indicated that symptomatology as well as neurocognitive and social-cognitive ability are important factors in relation to functional outcome. Specifically, (1) Disorganized symptoms predicted outcome levels more strongly then other symptoms for deaf and hearing subjects alike. (2) While both groups exhibited similar deficits in neurocognition and social cognition, hearing status appeared to moderate certain relationships. For example, verbal memory was the strongest predictor of functional outcome for hearing subjects while linguistic ability was the strongest predictor for deaf subjects. (3) While social cognition mediated the relationship between neurocognition and functional outcome for both groups, the patterns of mediation varied when the samples were broken down by hearing status. Namely, the ability to infer another person's intentions (i.e., theory of mind) served as a potent mediator of the relationship between neurocognition and functional outcome for hearing subjects only. For deaf subjects, facial affect processing served as the most potent mediator. Implications: The findings suggest that the development of rehabilitation strategies for PWS should include not only interventions targeting specific neurocognitive abilities such as memory, but also interventions for social-cognitive domains including facial affect processing and theory of mind. Further, deaf and hearing subjects may benefit from interventions that address different aspects of cognition. With information about deafness and its association with functioning we can begin to develop more effective interventions and identify less-restrictive care settings for deaf people with schizophrenia. As treatment interventions for schizophrenia evolve, cognitive rehabilitation should be part of an intensive, structured, and interdisciplinary rehabilitation program.