Rationale
When dissimilar figures are presented to each eye individually, perception alternates spontaneously between each monocular
view. This phenomenon, binocular rivalry, has been suggested to depend on serotonergic neural systems.
Objective
To investigate the relationship between binocular rivalry and serotonergic neural systems in more detail, we measured the
perceptual alternation rate and rhythmicity of binocular rivalry under the influence of the 5-HT1A agonist tandospirone.
Materials and methods
Fifteen healthy volunteers were tested under placebo and 60 mg tandospirone conditions using the single-blind method. The
perceptual alternation rate and rhythmicity of binocular rivalry were measured at pre-administration and at 90, 180, and 360 min
post-administration.
Results
Compared to placebo, the administration of tandospirone decreased the rate and rhythmicity of perceptual switching significantly
at 90 and 180 min post-administration in a manner that is consistent with its pharmacokinetics.
Conclusions
The present results suggest that the 5-HT1A neural pathways, mainly located in the mesolimbic system and brainstem, may play a crucial role as an oscillator in perceptual
rivalry alternations.
Keywords Anxiolytic - Binocular rivalry - Rhythmicity - Serotonergic system - Tandospirone - Cognition