Individuals with psychotic symptoms were found to overweight initial information and to be slower at updating information, according to results of a case-control study, published in JAMA Psychiatry.

Patients (n=90) with clinically stable schizophrenia or schizoaffective disorder (PSZ) and matched controls (n=70) were recruited for 2 independent samples at the Maryland Psychiatric Research Center, Yale University, and community clinics between 2018 and 2020. Study participants were assessed for neuropsychological symptoms and underwent a perceptual updating test using a dot kinematogram paradigm implementation.

Compared with controls, the patients with PSZ received fewer years of formal education, had lower Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery (MCCB) scores, higher Peters Delusions Inventory (PDI) scores, and higher Brief Psychiatric Rating Scale (BPRS) scores (all P ≤.006).


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In the original sample, the PSZ cohort had a lower proportion of target responses (t, 5.34; P <.001) as well as in the replication sample (t, 2.79; P =.007). Patients with PSZ often failed to update after the dots changed direction, instead focusing on the original motion more than controls (mean, original: 27.88 vs 18.86; P <.001; replication: 26.70 vs 15.67; P <.001).

The PSZ cohort were less precise than the controls, having a greater mean response error in both the original (t, -3.69; P <.001) and replication (t, -2.14; P =.04) samples.

The PSZ participants reported a change in dot movement significantly later (t, 4.87; P <.001) than controls (t, 3.16; P =.002). However, patients with PSZ reported the initial direction more quickly than controls.

For no-change trials, the PSZ cohort had longer reaction times, fewer responses were centered on the target direction, they had more lapses, and less precision reporting the motion.

The investigators observed correlations between PDI conviction ratings (t, 2.52; P =.02) and BPRS reality distortion (t, 4.42; P <.001) with the accuracy of motion direction among the original sample. For the replication sample, only the BPRS reality distortion association was confirmed (t, 2.44; P =.02).

This study was limited as only a small amount of the variance in psychosis severity was accounted for by these observations.

The study authors concluded that the processes involved with accumulating, evaluation, and updating evidence may be assessed using simple perceptual judgement paradigms and that individuals with psychotic symptoms likely overweight initial information and are slow to update.

Disclosure: An author declared affiliations with industry. Please refer to the original article for a full list of disclosures.

Reference

Bansal S, Bae G-Y, Robinson BM, et al. Association between failures in perceptual updating and the severity of psychosis in schizophrenia. JAMA Psychiatry. Published online December 1, 2021. doi:10.1001/jamapsychiatry.2021.3482