Anxiety sensitivity and the anticipation of predictable and unpredictable threat: Evidence from the startle response and event-related potentials

Abstract

There is growing evidence that heightened sensitivity to unpredictable threat is a core mechanism of dysfunction in anxiety disorders. However, it is unclear whether anxiety sensitivity is also associated with sensitivity to unpredictable threat. In the present study, 131 participants completed the Anxiety Sensitivity Index-3, which includes physical concerns (PC), social concerns (SC), and cognitive concerns (CC) subscales, and a predictable vs. unpredictable threat-of-shock task. Startle eyeblink and ERP responses (N100, P300) to the acoustic startle probes were measured during the task. PC and CC were associated with heightened and attenuated, respectively, startle for the unpredictable (but not predictable) condition. CC were also associated with attenuated probe N100 for the unpredictable condition only, and PC were associated with increased P300 suppression across the predictable and unpredictable conditions. This study provides novel evidence that the different anxiety sensitivity dimensions demonstrate unique relationships with the RDoC domains "acute" and "potential" threat.

Keywords: Anxiety sensitivity; Event-related potentials; Predictability; Startle response.

Figure 1

Waveforms (left) and head maps (right) for the PCA-derived N100 (top) and P300 (bottom). Data were collapsed across CD and ISI phases of each threat condition. The x- and y-axes are at difference scales for the N100 and P300 figures. CD = countdown; ISI = inter-stimulus interval; ms = milliseconds; N = no threat; P = predictable threat; PCA = princal components analysis; U = unpredictable threat.

Figure 2

Scatterplots depicting the association between ASI-3 PC residuals and startle potentiation during the U_CD+ISI (relative to the N_CD+ISI; top), P300 suppression (more negative values indicate greater suppression) during the P_CD+ISI and U_CD+ISI (relative to the N_CD+ISI; middle), and self-reported anxiety across all conditions. ASI-3= Anxiety Sensitivity Index-3; au = arbitrary units; CD = countdown; ISI = inter-stimulus interval; N = no threat; P = predictable threat; PC = physical concerns; U = unpredictable threat.

Figure 2

Scatterplots depicting the association between ASI-3 PC residuals and startle potentiation during the U_CD+ISI (relative to the N_CD+ISI; top), P300 suppression (more negative values indicate greater suppression) during the P_CD+ISI and U_CD+ISI (relative to the N_CD+ISI; middle), and self-reported anxiety across all conditions. ASI-3= Anxiety Sensitivity Index-3; au = arbitrary units; CD = countdown; ISI = inter-stimulus interval; N = no threat; P = predictable threat; PC = physical concerns; U = unpredictable threat.

Figure 3

Scatterplots depicting the association between ASI-3 CC residuals and startle potentiation during the U_CD+ISI (relative to the N_CD+ISI; top) and N100 enhancement (more negative values indicate greater enhancement) during the U_CD (relative to the N_CD; bottom). ASI-3 = Anxiety Sensitivity Index-3; CC = cognitive concerns; CD = countdown; ISI = inter-stimulus interval; U = unpredictable threat.