Effects of food-related stimuli on visual spatial attention in fasting and nonfasting normal subjects: Behavior and electrophysiology.

OBJECTIVE Attention biases toward food-related stimuli were examined as mediators of normal, healthy motivated behavior. METHODS Reaction times (RTs) and event-related potentials (ERPs) were used to assess the impact of food-related words on normal food-deprived individuals when used as spatial cues that frequently predicted the location of targets in a simple detection task (75% validity). RESULTS In Experiment 1, fasting and nonfasting subjects showed a magnified cost/benefit of invalid/valid cueing by food words relative to a neutral category of words. In Experiment 2, the RT effect was replicated in a group of fasting subjects. The amplitude of a P3-like positivity (P420) was enhanced in response to food words, as was that of a prominent early anterior negativity (AN). CONCLUSIONS These findings demonstrate that food-related stimuli can bias spatial attention in normal subjects and that electrophysiological markers can index the motivational salience of food words and/or their effect on attentional capture in food-deprived individuals. SIGNIFICANCE Even when the motivational salience of spatial cues is irrelevant to task demands, it can have an observable effect on attention. This design allows for the behavioral and electrophysiological study of motivation-attention interactions through loading of spatial cues with motivation-related semantic properties.