Affective and temporal orientation of thoughts: Electrophysiological evidence

The factors that determine the content and valence of spontaneous thoughts have not yet been clarified. In this study, we focused on the effects of bodily states and depression and anxiety traits. Participants performed a past/future thinking task in which three-part sentences including temporal cues were presented in a sequential pattern, for example "in the near future/dreams/will come true". We measured heartbeat-evoked potentials (HEPs) to assess affective processing, and event-related potentials (ERPs) to assess temporal processing of thoughts that emerged when the temporal cue words were presented. The HEPs predicted thought valence irrespective of personality traits. Larger N400 ERPs were observed in response to past-oriented than to future-oriented words in participants with higher levels of depression, whereas the opposite was the case in participants with higher social anxiety. Our data suggest that afferent signals modulate affective thought-orientations as triggers, and that individuals with depression and anxiety have sensitivity toward temporal information at the neural level.