The impact of affective states and traits on perceptual stability during binocular rivalry

Affective states and traits have been associated with different measures of perceptual stability during binocular rivalry. Diverging approaches to measuring perceptual stability as well as to examination of the role of affective variables have contributed to an inconclusive pattern of findings. Here, we studied the influence of affective traits, such as depressiveness and trait anxiety, and states, which were manipulated with a musical mood induction paradigm, on different measures of perceptual stability (dominance ratios and phase durations) during binocular rivalry. Fifty healthy participants reported alternations in two conditions: a biased perception condition with an unequal probability of perceiving stimuli, using an upright versus a tilted face with a neutral expression, and a control condition with equal chances of perceiving stimuli, using Gabors of different orientations. Baseline positive state affect significantly predicted longer phase durations whereas affective traits did not yield any such effect. Furthermore, in an exploratory analysis, induced negative affect attenuated stimulus related bias in predominance ratios. Overall, we found a strong correlation between both measures of perceptual stability (phase durations and dominance ratios). Our findings thus question the distinction between different measures of perceptual stability during binocular rivalry and highlight the role of affective states in its formation.