The (neuro)cognitive mechanisms behind attention bias modification in anxiety: proposals based on theoretical accounts of attentional bias

Abstract

Recently, researchers have investigated the causal nature of attentional bias for threat (AB) in the maintenance of anxiety disorders by experimentally manipulating it. They found that training anxious individuals to attend to non-threat stimuli reduces AB, which, in turn, reduces anxiety. This effect supports the hypothesis that AB can causally impact the maintenance of anxiety. At a fundamental level, however, uncertainty still abounds regarding the nature of the processes that mediate this effect. In the present paper, we propose that two contrasting approaches may be derived from theoretical accounts of AB. According to a first class of models, called the "valence-specific bias" models, modifying AB requires the modification of valence-specific attentional selectivity. According to a second class of models, called the "attention control models," modifying AB requires the modification of attention control, driven by the recruitment of the dorsolateral prefrontal cortex. We formulate a series of specific predictions, to provide suggestions to trial these two approaches one against the other. This knowledge is critical for understanding the mechanisms of AB in anxiety disorders, which bares important clinical implications.

Keywords: DLPFC; attentional bias; cognitive bias modification; experimental psychopathology; neuromodulation.

Figure 1

Sequence of the attention bias modification procedure. Note: In the original version of the dot-probe paradigm, participants viewed two stimuli (i.e., a threatening and a neutral) presented in two areas of a computer screen for approximately 500 ms. Immediately after the pictures disappeared, a probe replaced one of the stimuli. Participants responded to the probe as quickly as possible. In attention training, researchers typically modify the original task such so that the probe nearly always (i.e., 95% of the trials) replaces the neutral stimulus, thereby redirecting subjects' attention to non-threat cues. In the control condition, there was no contingency between cues and probes.

Figure 2

A schematic summary of the different models depicted in the present article. Note: (A) A first position proposes a strong causal antecedent role for the VES, claiming that the reduction of AB necessarily involves a modification of the valence-specific bias without involving an improvement in AC. (B) In contrast, a second position suggests that ABM involves an improvement in AC without any modification of the VES. (C) A third position suggests that both VES and AC are causally involved in the reduction of AB. (D) It has been suggested that the DLPFC may be considered as a proxy of AC, whereas the amygdala as a proxy of the VES. Abbreviations: AB, Attentional Bias; AC, Attention Control; DLPFC, Dorsolateral Prefrontal Cortex; VES, Valence Evaluation System.