ERPs of metaphoric, literal, and incongruous semantic processing in schizophrenia

Abstract

The ability of schizophrenia patients to access metaphorical meaning was studied on the basis of psycholinguistic models of metaphor processing. ERPs were recorded from 20 schizophrenic and 20 control participants who were asked to read metaphorical, literal, and incongruous sentences and to judge their meaningfulness. In all participants, incongruous endings to sentences evoked the most negative N400 amplitude, whereas literal endings evoked more negative N400 amplitude than metaphorical ones, consistent with the direct model of metaphor processing. Although the patients had ERPs patterns that were similar to controls, they exhibited a more negative N400 amplitude for all sentences, LPC amplitude reduction, and latency delay in both components. The results suggest that schizophrenics have no specific anomalies in accessing the meaning of metaphors but are less efficient in integrating the semantic context of all sentences--both figurative and literal.

Test–retest reliability of N400 event-related brain potential measures in a word-pair semantic priming paradigm in patients with schizophrenia

“…Although the literature includes substantial evidence for smaller than normal N400 semantic priming effects in schizophrenia patients compared to controls (Bobes et al, 1996;Strandburg et al, 1997;Ohta et al, 1999;Condray et al, 2003;Kostova et al, 2003;Iakimova et al, 2005;Kostova et al, 2005;Ditman & Kuperberg, 2007;Kiang et al, 2008;Salisbury, 2008;Guerra et al, 2009;Condray et al, 2010;Mathalon et al, 2010;Kiang et al, 2011;Kiang et al, 2012;Kiang et al, 2014), our findings do not allow for a definitive conclusion that the current sample had smaller than normal N400 semantic priming effects (as suggested by an absence of significant differences between N400 mean amplitude for contextually related and unrelated target words).…”

Interpretation of Ambiguous Idiomatic Statements in Schizophrenic and Depressive Patients. Evidence for Common and Differential Cognitive Patterns

“…However, considered in conjunction with Titone et al's fi ndings [30] , the response profi le obtained from the schizophrenia patients suggests that they were less infl uenced by the global contextual characteristics of the task which led the other participants to exclude the literal meaning and select fi gurative responses. This result may refl ect anomalies in the processing of the semantic context revealed in various studies of language processing in schizophrenics [23,51,52] . Finally, we conducted a descriptive analysis of the results obtained from the schizophrenic patients, which revealed that literal responses were observed with similar frequencies in all patients -unlike concrete responses, which were not always observed (see fi gure 1 ).…”

Metaphor Processing in Schizophrenia Patients: A Study of Comprehension and Explanation of Metaphors

“…It was observed that patients with SZ make rather literal than figurative interpretations (Brune & Bodenstein, 2005;Chapman, 1960;Elvevag, Helsen, De Hert, Sweers, & Storms, 2011;Kiang et al, 2007). Although this was not so in a study by Iakimova, Passerieux, Laurent, and Hardy-Bayle (2005), in which the authors showed that SZ patients were rather impaired in interpreting the semantic context of sentences, both figurative and literal, rather than showing a specific deficit in metaphor processing. In some other studies, patients with SZ were found to have difficulty in judging if a sentence represented a plausible or implausible metaphor (Corcoran, 1999), in choosing the metaphor that matches the meaning of a proverb (de Bonis, Epelbaum, Deffez, & Feline, 1997) or in assessing whether a metaphor is appropriate to a given situation (Langdnon, Davies, & Coltheart, 2002).…”