Abstract

Background: Reaction time (RT) is an index of brain’s biological efficiency. RT can indicate sensorimotor variability with varying foreperiods (FPs) and can indicate mental dysfunction like schizophrenia.

Aims and Objective: Objective was to analyze the effect variable FPs on RTs in controls and schizophrenic patients.

Materials and Methods: The study was conducted at Topiwala National Medical College, Mumbai, on 80 normal controls and 80 schizophrenic patients in the age group of 20-50 years. Digital RT apparatus (RTM-608) manufactured by Bio-Tech., with a maximum resolution time of 0.0001 s was used. Auditory RT (ART) and visual RT (VRT) with randomly variable FPs (2, 4, and 6 s) were recorded in controls and schizophrenic patients.

Results: Two-way ANOVA with replication in MS Office Excel was used to analyze results. ARTs and VRTs in schizophrenic patients were significantly slower than that in controls with P = 1.4336E-215 with F = 6779.53969 and P = 2.5966E-209 with F = 6161.152654, respectively. The condition effect was also significant with ARTs and VRTs, increasing in patients with increase in the FPs with P = 4.84285E-16 with F = 73.35131426 (ART) and P = 2.72532E-14 with F = 63.68037666 (VRT), respectively. The Group X condition interaction also was significant with P = 8.80207E-12 with F = 50.27084108 in case of ARTs and P = 1.21054E-10 with F = 44.36301991 in case of VRTs.

Conclusion: This shows that variation in FPs results in slower RTs in schizophrenic patients than in controls.

Key words: Choice Reaction Time; Foreperiod; Variable; Cognition; Schizophrenia