EEG theta/beta ratio in relation to fear-modulated response-inhibition, attentional control, and affective traits.

Power density-ratios of fast and slow frequency spectrum-bands can be calculated from resting-state electroencephalography (EEG) recordings. A well-established phenomenon is that slow wave/fast wave ratios (SW/FW) are increased in attention-deficit/hyperactivity disorder. Several researchers have also begun to study relationships between SW/FW and affect. This work suggests that increased SW/FW may reflect reduced frontal cortical control over subcortical affective approach drive. The present study (n=28) aimed to further examine this notion by testing several predictions derived from it. In line with these predictions, SW/FW was found to correlate negatively with fearful modulation of response inhibition in an emotional go/no-go task and with self-reported attentional control. Results also suggested a positive relation between SW/FW and trait approach motivation and a negative relation to anxiety, as predicted. These results are consistent with previous studies and support the notion that SW/FW may provide a useful tool in the study of affect and emotion regulation. Copyright 2009 Elsevier B.V. All rights reserved.