Study on the processing of syntactic contextual information during a lexical decision task in schizophrenic subjects

Objective: This research report studies how schizophrenic subjects process contextual syntactic information using a double-decision lexical task (deciding whether or not strings of letters form French words). Given the automatic nature of syntax, we are assuming the preservation of syntactical information processing in all the schizophrenic subjects, including those presenting thought disorder (TFP), which we name schizophrenic TPF+. Method: Twenty control subjects and 20 schizophrenic subjects (including 10 TFP+ schizophrenic subjects) participated in a double-decision lexical task containing syntactic errors. Results: The results confirm our hypothesis because we show that all subjects (control and schizophrenic) are hampered in recognizing words when they contain grammatical errors. Conclusions: The results contrast with data on the processing of contextual semantic information by schizophrenic subjects, since the data in the literature conclude that there is an information-processing anomaly on the part of these patients. As a result, our study refutes the hypothesis of a generalized difficulty in the processing context by schizophrenic subjects.