(PS3-37) The Association Between Depression and Theta Oscillations Under Inhibitory Demands

Research evidence indicates that depression, anxiety, and stress are associated with weakened cognitive inhibition, resulting in the failure to inhibit irrelevant information like ruminations or negative thoughts (Dierolf et al., 2017; Gohier et al., 2009; Mathews and Dalgleish, 2001). Cognitive inhibition refers to the ability to suppress potent task-irrelevant details to resolve relevant task problems (e.g., Flanker task; interference; Haciahmet et al., 2021). Consequently, a cognitive marker that can distinguish unique inhibitory deficits between depression, anxiety, and stress will be of great importance as a treatment marker for intervention. Electroencephalography (EEG) is one method that can help distinguish the unique inhibitory deficits between depression, anxiety, and stress. Specifically, oscillatory activity within the theta band has been shown to be more associated with interference control during cognitive inhibition demands (Cavanagh & Frank, 2014; Cohen & Donner, 2013; Haciahmet et al., 2021). Thus, the goal of the present study was to characterize depression, anxiety, and stress using theta band oscillations during a flanker task. Young adults (N=63, M age = 22.3 years, 53 women) completed a flanker task while 32-channel EEG data was acquired, in which theta band power at frontal electrode Fz was calculated for successfully inhibited trials using EEGLAB function newtimef. We measured the severity of depression, anxiety, and stress using the Depression Anxiety Stress Scale (DASS-21). Associations between depression, anxiety, and stress severity and theta power during cognitive inhibition (CI) were examined. Additionally, these associations were controlled for age, sex, treatment history, ethnicity, and race. Three hierarchical linear regression analysis were conducted with depression, anxiety, and stress separately as the dependent variable, covariates (e.g., sex, race) in Step 1, and theta CI as the main predictor in Step 2. The depression model was significant (p = .005, R² = .160, ΔR² = .089), such that theta CI was a significant predictor of depression severity (p = .005, β = -.308). The anxiety model was not significant (p = .068, R² = .143, ΔR² = .038), such that theta CI was not a significant predictor of anxiety severity (p = .068, β = -.200). The stress model was not significant (p = .216, R² = .111, ΔR² = .018), such that theta CI was not a significant predictor of stress severity (p = .216, β = -.138). Collectively, attenuated theta CI is significantly associated with greater depression severity. Our data indicate that theta within cognitive inhibition demands may have potential as a potential target of intervention for individuals suffering from depression.