In this study, effects of interaction of anger with anxiety on the perception of emotional facial expressions and associated with this perception oscillatory dynamics of cortical responses elicited by presentation of angry, neutral, and happy faces were investigated. Subjects filled out the Buss–Perry aggression scales and the Spielberger’s State Trait Anxiety Inventory. Anxiety moderated the effect of anger both on estimates of angry and happy faces and on face presentation-related spectral perturbations. In the low anxiety group, anger scores were positively related to the extent of face presentation-related theta synchronization. In the high anxiety group this effect was not significant. The results are discussed in light of Corr’s “joint subsystems” hypothesis (Corr, 2002).
The ability to understand emotional information conveyed by facial expressions of other people is crucial for building interpersonal relationships, career, and, sometimes, even survival (Ellis & Young, 1998). The human face provides the most salient cue to another person’s emotional state. Facial expressions are the unique source of information having social meaning (Bruce & Young, 1986). Existing empirical research shows that some personality traits such as anger and anxiety are associated with biases in the perception of emotionally loaded stimuli, particularly such socially significant stimuli as emotional facial expressions. Individuals scoring high on trait anger showed an attentional bias for angry faces (Putnam et al., 2004 and van Honk et al., 2001). High anger subjects attributed more hostility to characters of situations (Epps & Kendall, 1995) or more negativity to explanations of events (Wenzel & Lystad, 2005). Participants high on trait anxiety show attentional biases toward threatening information (Derryberry and Reed, 2002, Fox, 2002 and Weinstein, 1995). High as opposed to low anxiety subjects show larger negative emotional reaction during presentation of angry faces and rate these faces as more unpleasant and as expressing more disgust (Dimberg & Thunberg, 2007). Previously we have shown that anger and anxiety were associated with a tendency to perceive all facial expressions as more hostile (Knyazev et al., 2008b and Knyazev et al., 2009). These perceptional biases are bound to have some psychophysiological manifestation. However, until recently, few studies took into account personality-related individual differences in the face presentation-related cortical oscillatory responses. We have shown recently that anxiety and anger show opposite effects on face presentation-related oscillatory responses. Anger is associated with increased theta band synchronization and decreased alpha band desynchronization (Knyazev et al., 2009), whereas anxiety shows the opposite pattern of relations (Knyazev, Bocharov, Levin, Savostyanov, & Slobodskoj-Plusnin, 2008a). This is puzzling, because, as we discussed earlier, at perceptional level these traits show similar biases (i.e., exaggeration of aggressiveness and hostility in the facial expressions). From a theoretical perspective, the observed differences in oscillatory dynamics seem more corresponding to behavioural manifestations, because in terms of behavioural outcome, anger and anxiety underlie opposite behavioural tendencies – approach and avoidance behaviour, respectively. One way to try to resolve this puzzle would be to more scrupulously investigate the effects of different combinations of anger and anxiety on the perception of different facial expressions and associated cortical oscillatory responses. The majority of published studies investigated isolated effects of anger or anxiety and, to the best of our knowledge, no studies investigated effects of different combinations of these traits. This is unfortunate, because in reality each individual has some combination of anger and anxiety and his or her behaviour depends on their interaction. Therefore, in this study we aimed to investigate the interaction between anger and anxiety in their influence on the perception of emotional facial expressions and on associated with this perception oscillatory cortical responses. Theoretically, there could be two possibilities: (1) the two traits do not interact with each other (i.e., effects of, e.g., anger would be similar on different levels of anxiety); (2) the two traits interact with each other. In the latter case, effects of one trait on the outcome variable would be different on different levels of another trait.
