Reasoning about the implications of facial expressions: a behavioral and fMRI study on low and high social impact.

Inferring the cause of another person's emotional state is relevant for guiding behavior in social interactions. With respect to their potentially evoked behavioral reactions some emotional states like anger or happiness are considered to have high social impact while others such as fear and sadness have low social impact. We conducted a functional magnetic resonance imaging study to map the brain activation patterns related to reasoning about facial expressions of emotions with high or low social impact in twenty-six healthy volunteers with good emotional competence, self-reported empathy, and explicit facial affect recognition abilities. Our data show that empathic reasoning was faster and more accurate for high impact emotional states than for low impact emotional states. Activated brain areas involved brain circuits associated with basic and higher order empathy and decision-making in the dorsomedial and dorsolateral frontal cortex. However, activation in higher order areas was less during reasoning about emotional states of high social impact. Taken together, reasoning of high and low impact emotional states relied on similar empathy-related brain areas with reasoning about emotional states of low social impact being more erroneous and requiring more cognitive resources.

Processing of subliminal facial expressions of emotion: a behavioral and fMRI study.

The recognition of emotional facial expressions is an important means to adjust behavior in social interactions. As facial expressions widely differ in their duration and degree of expressiveness, they often manifest with short and transient expressions below the level of awareness. In this combined behavioral and fMRI study, we aimed at examining whether or not consciously accessible (subliminal) emotional facial expressions influence empathic judgments and which brain activations are related to it. We hypothesized that subliminal facial expressions of emotions masked with neutral expressions of the same faces induce an empathic processing similar to consciously accessible (supraliminal) facial expressions. Our behavioral data in 23 healthy subjects showed that subliminal emotional facial expressions of 40 ms duration affect the judgments of the subsequent neutral facial expressions. In the fMRI study in 12 healthy subjects it was found that both, supra- and subliminal emotional facial expressions shared a widespread network of brain areas including the fusiform gyrus, the temporo-parietal junction, and the inferior, dorsolateral, and medial frontal cortex. Compared with subliminal facial expressions, supraliminal facial expressions led to a greater activation of left occipital and fusiform face areas. We conclude that masked subliminal emotional information is suited to trigger processing in brain areas which have been implicated in empathy and, thereby in social encounters.

A functional magnetic resonance imaging study of visuomotor processing in a virtual reality-based paradigm: Rehabilitation Gaming System.

The Rehabilitation Gaming System (RGS) has been designed as a flexible, virtual-reality (VR)-based device for rehabilitation of neurological patients. Recently, training of visuomotor processing with the RGS was shown to effectively improve arm function in acute and chronic stroke patients. It is assumed that the VR-based training protocol related to RGS creates conditions that aid recovery by virtue of the human mirror neuron system. Here, we provide evidence for this assumption by identifying the brain areas involved in controlling the catching of approaching colored balls in the virtual environment of the RGS. We used functional magnetic resonance imaging of 18 right-handed healthy subjects (24 ± 3 years) in both active and imagination conditions. We observed that the imagery of target catching was related to activation of frontal, parietal, temporal, cingulate and cerebellar regions. We interpret these activations in relation to object processing, attention, mirror mechanisms, and motor intention. Active catching followed an anticipatory mode, and resulted in significantly less activity in the motor control areas. Our results provide preliminary support for the hypothesis underlying RGS that this novel neurorehabilitation approach engages human mirror mechanisms that can be employed for visuomotor training.