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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.

We aimed to investigate the neural correlates associated with judgments of a positive self-conscious emotion, pride, and elucidate the difference between pride and a basic positive emotion, joy, at the neural basis level using functional magnetic resonance imaging. Study of the neural basis associated with pride might contribute to a better understanding of the pride-related behaviors observed in neuropsychiatric disorders. Sixteen healthy volunteers were studied. The participants read sentences expressing joy or pride contents during the scans. Pride conditions activated the right posterior superior temporal sulcus and left temporal pole, the regions implicated in the neural substrate of social cognition or theory of mind. However, against our prediction, we did not find brain activation in the medial prefrontal cortex, a region responsible for inferring others' intention or self-reflection. Joy condition produced activations in the ventral striatum and insula/operculum, the key nodes of processing of hedonic or appetitive stimuli. Our results support the idea that pride is a self-conscious emotion, requiring the ability to detect the intention of others. At the same time, judgment of pride might require less self-reflection compared with those of negative self-conscious emotions such as guilt or embarrassment.

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.

Recent neuroimaging studies have demonstrated abnormal central emotional processing in psychiatric disorders. The dopamine (DA) systems and serotonin (5-HT) systems are the main target of psychopharmacotherapy. DA D2 receptor antagonists and selective serotonin reuptake inhibitors (SSRIs) are widely used in psychiatric practice. Investigating the effects of these drugs on emotional processing should lead to a better understanding of the pathophysiology and pharmacotherapy of neuropsychiatric disorders. We aimed to examine effects of dopaminergic and serotonergic manipulation on neural responses to unpleasant pictures in healthy volunteers using pharmacological fMRI. Thirteen healthy male subjects participated in a single-blind, randomized, placebo-controlled design study. Each subject participated in three fMRI sessions. In each session, participants were orally administered either 25 mg of sultopride or 50 mg of fluvoxamine or placebo prior to scanning, and neural responses to unpleasant and neutral pictures were recorded. Despite no significant differences being found in the subjective ratings of affective pictures across three sessions, compared to placebo, acute treatments of DA D2 receptor antagonists and SSRIs commonly attenuated the amygdala activity, although both treatments had slightly different modulatory effects on other components of the neural circuit of emotional processing. This study has shown that even acute treatment of drugs that manipulate neurotransmitter systems could affect brain activation associated with emotional processing in human brain. At the same time, our findings suggest that pharmacological fMRI could be a powerful tool for investigating the neurophysiological properties of drugs targeting neuropsychiatric disorders.

We aimed to investigate the neural substrates associated with evaluative process of moral emotions. Using functional magnetic resonance imaging (fMRI), we examined the similarities and differences between evaluative process of guilt and that of embarrassment at the neural basis level. Study of the neural basis of judgments of moral emotions might contribute to a better understanding of the amoral behavior observed in neurological and psychiatric disorders. Nineteen healthy volunteers were studied. The participants read sentences carrying neutral, guilty, or embarrassing contents during the scans. Both guilt and embarrassment conditions commonly activated the medial prefrontal cortex (MPFC), left posterior superior temporal sulcus (STS), and visual cortex. Compared to guilt condition, embarrassment condition produced greater activation in the right temporal cortex (anterior), bilateral hippocampus, and visual cortex. Most of these regions have been implicated in the neural substrate of social cognition or Theory of Mind (ToM). Our results support the idea that both are self-conscious emotions, which are social emotions requiring the ability to represent the mental states of others. At the same time, our functional fMRI data are in favor of the notion that evaluative process of embarrassment might be a more complex process than that of guilt.

Objective Although language and culture are different in each area in the world, how does culture affect the recognition of nonverbal emotional vocalisations? A previous study on non-verbal emotional vocalisations has shown a cross-cultural effect in Western and African participants. However, nobody has ever investigated the cross-cultural differences between Japanese and Caucasian participants in their emotional response to non-verbal vocal sounds. In the present study, we aimed to investigate cross-cultural effect between Caucasian subjects and Japanese subjects when the subjects listen to nonverbal affect bursts. Method 30 Japanese subjects (15 males) participated in this study. The data of Japanese subjects were compared with data from 30 Canadian subjects (15 males). Subjects listened to the Montreal Affective Voices (MAVs), which consist of a database of nonverbal affect bursts portrayed by Canadian actors. Each voice was evaluated using three criteria: perceived emotional intensity in each of the eight emotions (Anger, Disgust, Fear, Pain, Sadness, Surprise, Happiness, and Pleasure), perceived valence, and perceived arousal. To investigate cross-cultural differences between Japanese and Canadian participants, mixed 238 ANOVAs with Group (Japanese, Canadian) and Emotion (eight emotions) as factors were calculated on ratings of Intensity, Valence, and Arousal. Results Significant Group 3 Emotion interactions were observed for ratings of intensity, valence and arousal (intensity: F(5.5, 313.5) = 9.137, p<0.001, valence: F(4.3, 244.3) = 25.101, p<0.001, arousal: F(4.4, 250.5) = 8.955, p<0.001). Post-hoc tests showed that intensity ratings from Japanese listeners were significantly higher than ratings from Caucasian listeners for angry, disgusted, fearful, surprise, and pleased (p<0.05/8). Further, valence ratings from Japanese listeners were significantly higher than ratings from Caucasian listeners for angry, disgusted, fearful, painful, surprised (p<0.05/9), whereas valence rating of pleased in Japanese listener was significantly lower than in Caucasian listener (p<0.05/9). Arousal ratings of sad vocalisations by Japanese listeners were significantly higher than by Caucasian listeners (p<0.05/9). Conclusion This study demonstrates important cross-cultural differences in the perception of non-verbal affect bursts and extends recent observations by showing that these cross-cultural differences are also found for negative emotions. [ABSTRACT FROM AUTHOR]