Background: Emotion regulation is part of our everyday executive functioning. Mood disorders such as bipolar disorder or depression are associated with dysfunctional emotion regulation. A...Show moreBackground: Emotion regulation is part of our everyday executive functioning. Mood disorders such as bipolar disorder or depression are associated with dysfunctional emotion regulation. A physiological measure of emotion regulation is heart rate (HR). People tend to show HR decrease to emotional stimuli, this is called bradycardia. Frontal-Theta/Beta-ratio (TBR) has shown to be a potential biomarker for multiple executive functions. In most frontal-TBR studies, a reversed correlation between frontal-TBR and level of executive functioning is found. Objective: The current study investigated if frontal-TBR plays a moderating role for emotion regulation of negative and positive stimuli. It was expected that low frontal-TBR would correlate with less fear-bradycardia and that low frontal-TBR would lead to better regulation of negative and positive stimuli. Methods: An emotion regulation task was used to induce physiological responses in participants. Participants (n=56) viewed 40 negative, 40 neutral and 40 positive pictures and were asked to attend or upregulate their emotional affect. Their physiological response was measured using ECG. Frontal-TBR was measured using EEG. Results: Against the hypotheses, results showed no moderating role for frontal-TBR on physiological reaction to positive or negative stimuli. There was a weaker fear-bradycardia than expected and no positive-bradycardia was found. Discussion: The absence of strong bradycardia in our sample blocks possibilities for a moderating role of frontal-TBR on emotion regulation. The results can be due to factors such as data collection method, stimuli selection or male/female distribution. Future studies should focus on replicating the frontal-TBR effects on emotion regulation of negative stimuli.Show less