Contemporary models of generalized anxiety disorder (GAD) posit that worry functions as an avoidance strategy. During worry, individuals inhibit threat-related imagery in order to minimize autonomic reactivity to phobic topics. This conceptualization of worry suggests a role for the executive system in exerting top-down inhibitory control (IC) over threat processing. We tested the hypothesis that better performance on an IC task would be associated with greater severity of worry and concomitant anxious mood. Forty-three older adults (age 60–77) with GAD completed the Stroop color word task and a battery of self-report symptom measures. Fifteen of the GAD patients were paired with age- and sex-matched non-anxious controls. In the full GAD sample, age-normed t-scores of Stroop performance were positively correlated with measures of worry and trait anxiety, but not anxious arousal or depression. Positive relationships between IC and symptom severity were upheld in the smaller subsample of GAD patients, while in the matched control group, no relationships between Stroop scores and clinical measures were observed. Patients and controls did not differ in Stroop performance. In the context of a disorder-specific tendency to make maladaptive use of executive functions, better IC may be associated with more severe symptomatology.
Generalized anxiety disorder (GAD) is a prevalent and disabling disorder characterized by pervasive, excessive, and uncontrollable worry (American Psychiatric Association, 2001). Contemporary models of GAD emphasize two central features of the condition: the persistence of pervasive and uncontrollable worry, and the notable absence of many of the somatic features (e.g. faintness, heart palpitations, and excessive sweating) that reliably characterize other anxiety disorders (Marten et al., 1994). For example, Borkovec's avoidance theory of worry (Borkovec, 1994; Borkovec, Alcaine, & Behar, 2004; Borkovec, Ray, & Stober, 1998) posits that worry is a cognitive avoidance strategy used to decrease discomfort level in the face of anxiety-provoking stimuli. Laboratory studies of voluntary worry have shown that worry is comprised of thoughts, as opposed to images (Borkovec & Inz, 1990), and, in contrast to imaginal processing, is associated with a reduction in autonomic nervous system response to fear material both during ( Vrana, Cuthbert, & Lang, 1986) and after ( Borkovec & Hu, 1990; Peasley-Miklus & Vrana, 2000) worry. Because worry is a successful strategy for the short-term suppression of anxious reactivity, worry is negatively reinforced as a coping tactic (e.g., Mowrer, 1947). However, worry is ultimately maladaptive because its strictly verbal nature precludes the comprehensive emotional processing (e.g., mental imagery, intense feelings of arousal, and imagining the ‘worst outcome’) believed to be necessary for fear extinction ( Foa & Kozak, 1986).
In the avoidance conceptualization of worry, avoidance of unwanted emotional/imaginal content is achieved through a selective processing strategy in which attention is directed toward verbal information and away from mental images. In a sense, the behavioral avoidance that characterizes other anxiety disorders is turned inward, necessitating a degree of cognitive dexterity in order to direct attention narrowly and avoid emotional contact with anxiety-provoking stimuli. This selective processing style may require proficiency in the effortful control of attention. During worry, an individual devotes attentional resources to the renumerative linguistic processing of threatening stimuli while holding at bay other demands on processing capacity. Because imaginal representations of the same aversive stimulus are likely to be primed repeatedly during the course of the worry episode (Borkovec et al., 2004), this task may require considerable inhibitory control (IC) of attention in order to maintain top-down attenuation of the fear response.
