Semantic priming in schizophrenia: A review and synthesis

Abstract

In this paper, we present a review of semantic priming experiments in schizophrenia. Semantic priming paradigms show utility in assessing the role of deficits in semantic memory network access in the pathology of schizophrenia. The studies are placed in the context of current models of information processing. In this review we include all English-language reports (from peer-reviewed journals) of single-word semantic priming studies involving participants with schizophrenia. The studies to date show schizophrenic patients to exhibit variable semantic priming effects under automatic processing conditions, and consistent impairments under controlled0attentional conditions. We also describe associations with other neurocognitive dysfunction, neurochemical and electrophysiological disturbances, and clinical manifestations (such as thought disorder).

Conscious and subliminal conflicts in normal subjects and patients with schizophrenia: The role of the anterior cingulate

“…Even within the blocks with conscious primes, repetition priming was unaffected. This dissociation between impaired ACC-PFC and intact behavioral forms of priming is consistent with the finding of normal or even enhanced repetition and semantic priming effects in schizophrenia (34,35). Automatic priming effects are thought to arise within perceptual and semantic posterior regions such as the visual word form system (19,23) where conflicting primes exert a subliminal competition that induces a measurable delay in response times.…”

“…This predicted dissociation of subliminal and conscious processing in schizophrenia has not been studied directly in the literature (but see refs. [34][35][36][37][38]. Given the evidence for multiple, distributed sites of brain dysfunction in schizophrenia, including ACC and PFC, the finding of preserved subliminal priming would provide strong evidence that ACC and PFC are not involved in automatic conflict resolution, but solely in conscious monitoring.…”

Schizophrenia and the structure of language: The linguist's view

“…According to a comprehensive review by Minzenberg et al (2002), in schizophrenia, experimental results involving automatic responses are quite variable; some show priming to be impaired, and some, especially in mania-like states, show it to be enhanced. Controlled (conscious) responses, however, are consistently impaired.…”

Abnormal cortical folding patterns within Broca's area in schizophrenia: Evidence from structural MRI

“…Cognitively, language deficits have been identified in children at risk for schizophrenia (Cannon et al, 2002;Fuller et al, 2002;Ott et al, 2001) as well as in patients in their first episode of psychosis (Fuller et al, 2002;Hoff et al, 1999). Numerous neuropsychological and psycholinguistic studies have established that patients with schizophrenia show selective language abnormalities as they monitor the source of verbal input (Ditman and Kuperberg, 2005;Johns et al, 2001), explicitly or implicitly retrieve information from semantic memory [e.g (Goldberg et al, 1998;Minzenberg et al, 2002)], select the appropriate meaning of semantically ambiguous words (Sitnikova et al, 2002;Titone et al, 2000), detect linguistic anomalies within sentences (Kuperberg et al, 2006a;Kuperberg et al, 1998;Kuperberg et al, 2000;Kuperberg et al, 2006b) and parse syntactically complex sentences (Condray et al, 1996) [for reviews, see (Kuperberg and Caplan, 2003;Kuperberg and Goldberg, 2006)]. Functional imaging studies report both abnormal increases and decreases in the recruitment of the left inferior prefrontal gyrus in schizophrenia during semantic tasks including encoding (Kubicki et al, 2003;Ragland et al, 2004), retrieval (Weiss et al, 2003) and priming (Kuperberg et al, 2007), although abnormal function in this region is not usually seen in isolation, but rather in association with abnormal modulation of other language regions including superior, inferior and medial temporal cortices.…”