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Abstract: While several studies have focused on identifying common brain mechanisms governing the decoding of emotional speech melody, interindividual variations in the cerebral processing of prosodic information, in comparison, have received only little attention to date: Albeit, for instance, differences in personality among individuals have been shown to modulate emotional brain responses, personality influences on the neural basis of prosody decoding have not been investigated systematically yet. Thus, the present study aimed at delineating relationships between interindividual differences in personality and hemodynamic responses evoked by emotional speech melody. To determine personality-dependent modulations of brain reactivity, fMRI activation patterns during the processing of emotional speech cues were acquired from 24 healthy volunteers and subsequently correlated with individual trait measures of extraversion and neuroticism obtained for each participant. Whereas correlation analysis did not indicate any link between brain activation and extraversion, strong positive correlations between measures of neuroticism and hemodynamic responses of the right amygdala, the left postcentral gyrus as well as medial frontal structures including the right anterior cingulate cortex emerged, suggesting that brain mechanisms mediating the decoding of emotional speech melody may vary depending on differences in neuroticism among individuals. Observed trait-specific modulations are discussed in the light of processing biases as well as differences in emotion control or task strategies which may be associated with the personality trait of neuroticism. [Copyright &y& Elsevier]

Abstract: Emotional communication is essential for successful social interactions. Emotional information can be expressed at verbal and nonverbal levels. If the verbal message contradicts the nonverbal expression, usually the nonverbal information is perceived as being more authentic, revealing the “true feelings” of the speaker. The present fMRI study investigated the cerebral integration of verbal (sentences expressing the emotional state of the speaker) and nonverbal (facial expressions and tone of voice) emotional signals using ecologically valid audiovisual stimulus material. More specifically, cerebral activation associated with the relative impact of nonverbal information on judging the affective state of a speaker (individual nonverbal dominance index, INDI) was investigated. Perception of nonverbally expressed emotions was associated with bilateral activation within the amygdala, fusiform face area (FFA), temporal voice area (TVA), and the posterior temporal cortex as well as in the midbrain and left inferior orbitofrontal cortex (OFC)/left insula. Verbally conveyed emotions were linked to increased responses bilaterally in the TVA. Furthermore, the INDI correlated with responses in the left amygdala elicited by nonverbal and verbal emotional stimuli. Correlation of the INDI with the activation within the medial OFC was observed during the processing of communicative signals. These results suggest that individuals with a higher degree of nonverbal dominance have an increased sensitivity not only to nonverbal but to emotional stimuli in general. [Copyright &y& Elsevier]

Voices and faces are the most common sources of threat in social anxiety (SA) where the fear of negative evaluation and social exclusion is the central element. SA itself is spectrally distributed among the general population and its clinical manifestation, termed social anxiety disorder, is one of the most common anxiety disorders. While heightened cerebral responses to angry or contemptuous facial or vocal expressions are well documented, it remains unclear if the brain of socially anxious individuals is generally more sensitive to voices and faces. Using functional magnetic resonance imaging, we investigated how SA affects the cerebral processing of voices and faces as compared to various other stimulus types in a study population with greatly varying SA (N = 50, 26 female). While cerebral voice-sensitivity correlated positively with SA in the left temporal voice area (TVA) and the left amygdala, an association of face-sensitivity and SA was observed in the right fusiform face area (FFA) and the face processing area of the right posterior superior temporal sulcus (pSTSFA). These results demonstrate that the increase of cerebral responses associated with social anxiety is not limited to facial or vocal expressions of social threat but that the respective sensory and emotion processing structures are also generally tuned to voices and faces. [ABSTRACT FROM AUTHOR]