We tested whether surprise elicits similar physiological changes as those associated with orienting and freezing after threat, as surprise also involves a state of interruption and attention for... Show moreWe tested whether surprise elicits similar physiological changes as those associated with orienting and freezing after threat, as surprise also involves a state of interruption and attention for effective action. Moreover, because surprise is primarily driven by the unexpectedness of an event, initial physiological responses were predicted to be similar for positive, neutral, and negative surprises. Results of repetition-change studies (4 + 1 in Supplemental Materials) showed that surprise lowers heart rate (Experiments 1-4) and increases blood pressure (Experiment 4). No effects on body movement (Experiment 2) or finger temperature (Experiment 4) were found. When unexpected stimuli were presented more often (making them less surprising) heart rate returned to baseline, while blood pressure remained high (Experiment 4). These effects were not influenced by stimulus valence. However, second-to-second analyses within the first (surprising) block showed a tendency for a stronger increase in systolic blood pressure after negative vs. positive surprise. Show less
Son, D. van; Angelidis, A.; Hagenaars, M.A.; Does, W. van der; Putman, P. 2018
Frontal EEG theta/beta ratio (TBR; negatively associated with attentional control, or AC) was previously reported to moderate threat‐level dependent attentional bias in a pictorial dot‐probe task,... Show moreFrontal EEG theta/beta ratio (TBR; negatively associated with attentional control, or AC) was previously reported to moderate threat‐level dependent attentional bias in a pictorial dot‐probe task, interacting with trait anxiety. Unexpectedly, this was independent from processing stage (using cue‐target delays of 200 and 500 ms) and also not observed for self‐reported trait AC. We therefore aimed to replicate these effects of TBR and trait anxiety and to test if effects of early versus late processing stages are evident for shorter cue‐target delays. This study also revisited the hypothesis that TBR and self‐reported trait AC show similar effects. Fifty‐three participants provided measurements of frontal TBR, self‐reported trait AC, trait anxiety, and dot‐probe task bias for mild and high threat pictures using the same dot‐probe task, but this time with 80‐ and 200‐ms cue‐target delays. Results indicated that higher TBR predicted more attention to mild than high threat, but this was independent from trait anxiety or delay. Lower self‐reported trait AC predicted more attention to mild than high threat, only after 200 ms (also independent of trait anxiety). We conclude that the moderating effect of TBR on threat‐level dependent dot‐probe task bias was replicated, but not the role of trait anxiety, and this study partially confirms that effects of trait AC are more dominant in later processing. Show less
Stoffels, M.; Nijs, M.; Spinhoven, P.; Mesbah, R.; Hagenaars, M.A. 2017
