Chunk #22 — Results — Frontal EEG Asymmetry as a Function of Lifetime DSM-IV-Defined Depression — Follow-up analyses: Current MDD status and depression severity
Two approaches were used to assess whether the apparent link between lifetime MDD status and frontal EEG asymmetry for the CSD-referenced data was due to current levels of depressive symptoms. The first approach reran the full factorial linear mixed model with CSD referenced data but instead of lifetime MDD status, current MDD status was used (current MDD+ = all participants with current MDD, regardless of past MDD status; past MDD+ = participants with past MDD but not current MDD or current dysthymia; MDD- = participants without current or past MDD or dysthymia; six participants with past MDD but current dysthymia were not included in these analyses). Current MDD status was the between-subjects variable, day and channel were within-subject variables, and EEG asymmetry score was again the dependent variable. Cohen's d is reported for significant differences between current MDD+, past MDD+, and MDD- groups. Based on EEG asymmetry results, the main effect of current MDD status was the effect of importance. Figure 2 illustrates that a main effect of current MDD status emerged (F(2, 297) = 14.1, p < .001), indicating
