Modulation of human auditory information processing by emotional visual stimuli

Auditory event-related potentials mismatch negativity (MMN) and N100 were recorded from seven subjects while they read text and watched emotionally negative, neutral, and positive pictures varying in valence and arousal. The MMN reflects automatic detection of change in auditory stimulus stream. Functionally different N100 is triggered by onset of various auditory stimuli. The N100 was stabile during all visual conditions. The MMN was very similar during text reading, and neutral and negative slide viewing, but was significantly attenuated during viewing of positively valenced slides. We suggest that visual emotional information of high positive valence and low arousal is a signal of nonthreatening and nonappetitive environment. This kind of environment probably reduces the need for auditory change detection.