Does arousal per se account for the influence of appetitive stimuli on attentional scope and the late positive potential?

Past research suggests that high approach-motivated positive affects narrow attentional scope and cause greater late positive potential (LPP) amplitudes. However, because arousal is related to motivational intensity, arousal may be responsible for these past findings. The present research investigated whether arousal, manipulated independently of affect using physical exercise, would influence attentional and LPP responses to stimuli. Results revealed that appetitive (vs. neutral) pictures evoked larger LPPs over central and left frontal regions, and caused more attentional narrowing. Individual differences in approach motivation predicted more attentional narrowing following appetitive stimuli. However, manipulated arousal did not influence attentional scope or LPPs to neutral or appetitive stimuli. Results suggest that attentional narrowing and LPPs to appetitive stimuli are related to approach motivation rather than enhanced general arousal.