Modafinil Decreased Thalamic Activation in Auditory Emotional Processing: A Randomized Controlled Functional Magnetic Resonance Imaging Study.

BACKGROUND: Modafinil improves wakefulness and attention, is approved in Japan for treatment of narcolepsy, and was reported to be effective for attention-deficit/hyperactivity disorder. However, it was reported to induce emotional instability, including mania, depression, and suicidal ideation. Such side effects may be related to changes in cognitive behavior caused by the effects of modafinil on emotional recognition. However, the effects of modafinil on the neural basis of emotional processing have not been fully verified. We used functional magnetic resonance imaging to investigate the effects of modafinil on the neural basis of auditory emotional processing. METHODS: This study adopted a placebo-controlled within-subject crossover design. Data from 14 participants were analyzed. The effects of modafinil on cerebral activation and task performance during an emotional judgement task were analyzed. RESULTS: Task accuracy decreased significantly and response time of emotional judgement was significantly delayed by modafinil, as compared with placebo. Right thalamic activation in auditory emotional processing was significantly less in the modafinil condition than in the placebo condition. In addition, reduction of right thalamic activation by modafinil was positively correlated with accuracy of emotional judgement. CONCLUSIONS: Our findings suggest that modafinil acts on the right thalamus and changes behavior and brain function associated with auditory emotional processing. These results indicate that modafinil might change emotional recognition by reducing emotional activation related to social communication.

Men and women show distinct brain activations during imagery of sexual and emotional infidelity.

Jealousy-related behaviors such as intimate partner violence and morbid jealousy are more common in males. Principal questionnaire studies suggest that men and women have different modules to process cues of sexual and emotional infidelity. We aimed to elucidate the neural response to sentences depicting sexual and emotional infidelity in men and women using functional magnetic resonance imaging. Although there was no sex difference in the self-rating score of jealousy for sexual and emotional infidelity, men and women showed different brain activation patterns in response to the two types of infidelity. During jealous conditions, men demonstrated greater activation than women in the brain regions involved in sexual/aggressive behaviors such as the amygdala and hypothalamus. In contrast, women demonstrated greater activation in the posterior superior temporal sulcus. Our fMRI results are in favor of the notion that men and women have different neuropsychological modules to process sexual and emotional infidelity. Our findings might contribute to a better understanding of the neural basis of the jealousy-related behaviors predominantly observed in males.