The association between high-power transient spectral beta events and depression in an elevated trait anxious sample

Recent work has reported that traditional averaged EEG power in fact comprises transient, oscillatory, burst-like events. Furthermore, transient events within the beta band have demonstrated a strong association with the depressive disease state; however, the impact of common comorbidities on this association, such as anxiety, is unknown. As such, this study sought to investigate whether features of beta events were associated with depression severity in a secondary analysis of an elevated trait anxiety sample. Twenty-nine adults who were screened for elevated trait anxiety completed eyes-closed resting state EEG. The rate, power, duration, and frequency span of transient oscillatory events were calculated within each frequency band (i.e., delta/theta, alpha, and beta) for 13 electrodes across the scalp. Depression severity was positively associated with beta event duration at electrodes P4 and O2. Subsequently, beta event duration was used to successfully distinguish the presence or absence of clinically moderate depression (i.e., individuals were classified as either presence or absence based on an established cutoff score). Further investigation into the utility of beta events as a biomarker of depression is warranted.