An EEG Signature of Suicidal Behavior in Female Patients with Major Depressive Disorder?: A Non-Replication

INTRODUCTION: A recent study showed hypoactivity in the beta/gamma band in female suicide ideators and suicide attempters diagnosed with depression, relative to a low-risk group. The current study aimed to conceptually replicate these results. METHODS: In the iSPOT-D sample (n = 402), suicide ideators and low-risk individuals were identified. Confining analyses to females only, differences between low-risk individuals and suicide ideators were tested for using the electroencephalogram (EEG) frequency bands SMR (Sensori-Motor-Rhythm; 12-15 Hz), beta (14.5-30 Hz), beta I (14.5-20 Hz), beta II (20-25 Hz), beta III (25-30 Hz), gamma I (31-49 Hz) using LORETA-software. RESULTS: None of the tested frequency bands showed to be significantly different between suicide ideators and low-risk individuals. CONCLUSIONS: The current study could not conceptually replicate the earlier published results. Several reasons could explain this non-replication, among which possible electromyographic (EMG) contamination in the beta/gamma band in the original study. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00693849 URL: http://clinicaltrials.gov/ct2/show/NCT00693849