Respiratory sensory gating measured by respiratory-related evoked potentials in generalized anxiety disorder

Abstract

The perception of respiratory sensations plays an important role both in respiratory diseases and in anxiety disorders. However, little is known about the neural processes underlying respiratory sensory perception, especially in patient groups. Therefore, the present study examined whether patients with generalized anxiety disorder (GAD) would demonstrate altered respiratory sensory gating compared to a healthy control group. Respiratory-related evoked potentials (RREP) were measured in a paired inspiratory occlusion paradigm presenting two brief occlusion stimuli (S1 and S2) within one inspiration. The results showed a significantly greater S2/S1 ratio for the N1 component of the RREP in the GAD group compared to the control group. Our findings suggest altered respiratory sensory processing in patients with GAD, which might contribute to altered perception of respiratory sensations in these patients.

Keywords: generalized anxiety disorder; respiratory sensation; respiratory sensory gating; respiratory-related evoked potentials.

FIGURE 1

Group averaged waveform from the C4 electrode. (A) The black solid lines represents the averaged S1 and S2 waveforms of the healthy control (HC) group (N = 18); (B) the black dashed lines represents the averaged S1 and S2 waveforms of the GAD group (N = 18).

FIGURE 2

Averaged RREP N1 peak S2/S1 ratio (mean ± SD) at the C3 and C4 electrodes. The shaded bars represent the averaged S2/S1 ratios of the HC group. The GAD group showed a significantly greater N1 S2/S1 ratio compared to the healthy controls at the C3 and C4 electrodes (p = 0.01 and 0.004, respectively).