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Difference in binocular rivalry rate between patients with bipolar I and bipolar II disorders



This article is corrected by:

  1. Errata: Corrigendum Volume 11, Issue 6, 672, Article first published online: 10 August 2009

  • AY has served as a speaker for Astellas Pharma, Inc., and GlaxoSmithKline K.K. SN has served as a speaker for Asahi Kasei Pharma, Astellas Pharma, Inc., GlaxoSmithKline K.K., Meiji Seika Kaisha, Ltd., Mitsubishi Pharma Corporation, and Pfizer Japan, Inc. MN, MM, and YT declare that they have no conflicts of interest to report.

Corresponding author:
Aihide Yoshino, M.D.
Department of Psychiatry
National Defense Medical College
3-2 Namiki, Tokorozawa
Saitama 359-8513, Japan
Fax: +81-42-996-5203


Objective:  When dissimilar figures are presented to each eye individually, perception alternates spontaneously between each monocular view. This phenomenon, known as binocular rivalry, has been used as a powerful tool to investigate conscious visual awareness. Of clinical relevance, Pettigrew and Miller (Proc Biol Sci 1998; 265: 2141-2148) found slow perceptual alternation rates in patients with bipolar I disorder (BD-I). For a better understanding of differences between BD-I and bipolar II disorder (BD-II), we examined whether perceptual alternation rates of binocular rivalry differ between the two subtypes of bipolar disorder.

Methods:  The subjects comprised 25 healthy controls, 11 patients with BD-I, and 17 patients with BD-II. They underwent binocular rivalry examination. One-way analysis of variance was conducted to determine differences in the phase duration of binocular rivalry between the control, BD-I, and BD-II groups.

Results:  Significant differences were observed in the mean phase duration of binocular rivalry between the groups. Although the medication administered did not differ significantly between the BD-I and BD-II patients, the phase duration was significantly longer among the BD-I patients than the BD-II patients and controls, whereas no significant difference was observed in the phase duration between the BD-II patients and controls.

Conclusion:  The present results reveal a significant difference in the mean phase duration of binocular rivalry between subjects with BD-I and those with BD-II, suggesting the presence of some neurobiological difference between these two subtypes of bipolar disorder.