Here is looking at you: Emotional faces predominate in binocular rivalry.

Abstract

Two incompatible pictures compete for perceptual dominance when they are presented to one eye each. This so-called binocular rivalry results in an alternation of dominant and suppressed percepts. In accordance with current theories of emotion processing, the authors' previous research has suggested that emotionally arousing pictures predominate in this perceptual process. Three experiments were run with pictures of emotional facial expressions that are known to induce emotions while being well controlled in terms of physical characteristics. In Experiment 1, photographs of emotional and neutral facial expressions were presented of the same actor to minimize physical differences. In Experiment 2, schematic emotional expressions were presented to further eliminate low-level differences. In Experiment 3, a probe-detection task was conducted to control for possible response-biases. Together, these data clearly demonstrate that emotional facial expressions predominate over neutral expressions; they are more often the first percept and they are perceived for longer durations. This is not caused by physical stimulus properties or by response-biases. This novel approach supports that emotionally significant visual stimuli are preferentially perceived.

Emotional scenes and facial expressions elicit different psychophysiological responses

“…Scores on the German version of the State Trait Anxiety Inventory (STAI; Laux et al, 1981) and on the German version of the Social Phobia Anxiety Inventory (SPAI; Fydrich, 2001) were somewhat higher than normative data (STAI: M = 41.8, SD = 10.2; SPAI: M = 3.3, SD = 0.9). However, they were well within the range of our previous student samples (Alpers and Gerdes, 2007;Alpers and Pauli, 2006;Alpers et al, 2005). One participant decided not to participate because of the aversive nature of the startle probe.…”

“…Neutral expressions may represent uncertainty, which could be a cue for non-reward or even punishment . Moreover, previous observations suggest that relaxed facial muscles sometimes do not appear to be perfectly neutral although the average of ratings represented in the usual statistics is close to neutral (Alpers and Gerdes, 2007). What was posed as neutral may be interpreted as surprisingly bleak and ambiguous, and their meaning may be less easily decoded than an angry face.…”

“…While emotional faces have been shown to be processed similar to emotional scenes in many ways, e.g., they both predominate perceptually in binocular rivalry (Alpers and Gerdes, 2007;Alpers and Pauli, 2006), direct comparisons of physiological or behavioral output are rare.…”

“…The strongest argument as to why differences in physiological output to scenes and faces should be expected is based on the finding that the modulation of physiological output is dependent on the level of arousal a stimulus induces. For example, the emotional modulation of the startle response can typically only be observed in pictures that elicit relatively high levels of arousal (Cuthbert et al, 1996), and the fact that emotional facial expressions often only elicit relatively low levels of arousal (e.g., Alpers and Gerdes, 2007). In order to address this question, we examined the influence of differences in the perceived level of arousal between scenes and facial expressions on the psychophysiological responses measured in an analysis of covariance.…”

“…Emotional faces and scenes have also been shown to be perceived preferentially, e.g., in binocular rivalry (Alpers and Gerdes, 2007;Alpers and Pauli, 2006) and they both strongly lead to attentional engagement Mogg and Bradley, 2002).…”