Human and environment influence each other dynamically and are co- adapting. Not only a specific stimulus influences people, but stimuli change may also trigger state transition. This dissertation treats dynamic stimuli with changing valence or intensity as probes to detect emotional responses and self- regulation, measuring electroencephalograph (EEG) and psychophysiological signals (ECG, skin conductance, eye tracking, respiration, etc.). I hypothesize that dynamic stimuli are more salient than static stimuli for emotional processes because they are unpredictable and consume more control resources. For ex- ample, intermittent noise may have a more negative impact than static noise. I designed four studies with different dynamic stimuli to understand how they influence emotion and the role of self-regulation. Study 1 shows that the deterioration of attention inhibition after dynamic emotional processing may reflect the additional cognitive effort required to process dynamic shifts in affective stimuli. I also found evidence this relationship is exacerbated by chronic stress. Study 2 further examined how flexible self- regulation is related to flexible neural activity change during affective stimuli transitions. Study 3 examined cortical and cardiovascular regulation to neural responses in an ambient sound environment. This study implicated that environmental context can trigger different self-regulation mechanisms both cortically and in the autonomic nervous system. Study 4 examined the effect of dynamic changes in brightness on acute stress recovery. Contrary to study 1, though dynamic sunlight captured more of people’s attention than static sunlight, it reduced beta power, which was associated with more relaxation. These studies suggest dynamic stimuli with transitions have more impact on people, and this may happen via shifts in executive functioning (task-switching, inhibition, and working memory). Furthermore, the impacts of self-regulation vary according to context.