The effects of latent trait-anxiety on attentional processing : An ERP investigation

The aim of the present dissertation was to investigate whether the operation of selective attention differs in people according to variation in latent trait-anxiety in conditions that were ostensibly absent of emotional valence. Repressors and high trait-anxious individuals appear to differ in the strategic operations undertaken to conduct these processes. Repressors show a tendency to attenuate and dismiss potentially threatening information, whereas high trait-anxious individuals show a tendency for amplification and focus. Two studies have reported findings of retarded attentional disengagement by high trait-anxious individuals in the absence of perceptible threat (i.e., Derakshan, Smyth & Eysenck, 2009; Derryberry & Reed, 2002). This suggests that the underlying strategic processes characteristic of high trait-anxiety operate independently of ostensible threat. To date, the proposition that this may also be the case with repressive coping style has not been investigated. This current investigation comprised three studies, each of which employed performance measures of response time and response accuracy. In addition, event-related potentials (ERPs) were employed as an index of subtle differences in the allocation of attentional resources. Participants were females aged between 17 and 34 years whom had never been formally diagnosed as having an anxiety disorder. The experimental paradigms employed with the three studies were selected for their ability to allow observation of component processes of selective attention. These were based on the mechanisms of disengagement, shifting and engagement described by Posner and Petersen (1990), which remains the leading model of the mechanisms of selective attention (Yiend, 2010). The first study employed a Stroop-interference experiment to investigate the inhibition of attention as a function of the disengagement sub-component of selective attention. The second study comprised a local-global Stroop-type interference paradigm embedded within a task-switching methodology toward investigating the degrees of operational flexibility possessed by the experimental groups on the subcomponents of selective attention. The final study was conducted to both investigate the prospect that repressors may possess a characteristic bias for enhanced attention to the discrete stimuli, and elucidate how low trait-anxiety and repressor groups compare on later-stage attentional processing. This comprised a combination of single-task and dual-task paradigms. Whereas the results of the final study were largely unremarkable, the convergent evidence from the Stroop-interference and task-switching studies offered reasonable support for the two-stage model of attentional processing in repression proposed in Vigilance-Avoidance Theory (Derakshan et al., 2007). Taken together, the findings of the present dissertation support the propositions that repressors represent a distinct sub-group of high trait-anxious people, and that the characteristic attentional processing styles of both of these groups operate independently of ostensible threat.