Time perception of simultaneous and sequential events in early-onset schizophrenia

ABSTRACT

Timing disorders in schizophrenia are a well-known phenomenon. However, no studies have yet assessed the role of temporal distortions in early-onset schizophrenia (EOS), despite evidence that distorted time perception may share genetic risk factors with schizophrenia and may be a useful indicator in identifying individuals at risk for schizophrenia. In the present study, we investigated the ability of 10 patients with EOS (mean age = 21.5 years, SD = 6) matched with 20 healthy control participants (mean age = 25.3 years, SD = 4.6) in order to compare the durations of two visual events, presented either sequentially or overlapping in time, along with neuropsychological assessments of attention, working memory, and executive functions. Each participant had to judge a total of 336 stimuli. We found that temporal overlap had a greater negative effect on ability to judge the duration of a pair of stimuli in EOS patients than in healthy control participants. In addition, EOS patients showed impairments in attention and executive functions. Furthermore, in EOS patients, the scores for executive and attentional functions were significantly correlated with accuracy of temporal estimation in the overlap condition (r = 0.31, p < 0.05 and r = 0.57, p < 0.05, respectively). These preliminary results suggest that impairments in neuropsychological functions participate in the deficit in time estimation observed in patients with EOS. These conclusions highlight the importance of testing time perception in patients with EOS and could contribute to the development of cognitive remediation-based therapy for these patients.

KEYWORDS:

• Early-onset schizophrenia
• time perception
• attention
• executive functions
• temporal overlap

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1. A bias toward perceiving the first or the second object as temporally longer is referred to in the literature as “time-order error” (TOE; Hellström, 1985). The TOE is positive when it corresponds to an overestimation of the first stimulus relative to the second, and negative in the opposite case. In our experiment, the TOE would be negative if the bias is larger than 1; for instance, a bias of 1.3 means that the duration of the second stimulus is overestimated by 30%.