[Features of reference choice in the linguistic analysis of speech in the schizophrenia spectrum disorders]

To identify errors of reference choice associated with the incorrect use of reference means for the linguistic analysis of the speech in patients with schizophrenia spectrum disorders.

The study included 53 male patients, with a mean age of 18.5±2.3 years: Group 1 with schizotypal disorder (F21) (n=33, 62.3%); Group 2 with schizophrenia (F20) (n=20, 37.7%). The control group included mentally healthy high school students and university students (n=33). The Positive and Negative Syndrome Scale (PANSS) and the Hamilton Depression Rating Scale (HDRS) were used. The participants were asked to watch a short film with no speech and retell what they saw. Erroneous use of reference means was noted in the speech. R and RStudio were used to analyze the data obtained.

The proportion of use of reduced reference means with reduced referent activation increases from the control group to the schizophrenia group, while normally such errors are virtually absent, and the group with schizotypal disorder falls in between. The difference between the three groups was statistically significant according to the Kruskal-Wallis test (H=20.233, p<0.001), as was the difference between the clinical groups of schizotypal disorder and schizophrenia according to the Mann-Whitney test (U=226, p=0.03781). There was a tendency to significantly increase the share of reference conflicts in the speech of schizophrenia patients. The difference among the three groups was statistically significant according to the Kruskal-Wallis test (H=17.621, p<0.001).

The obtained results can serve as an additional criterion for the differential diagnosis of the schizophrenia spectrum disorders.