Motor resonance is defined as the subliminal activation of the motor system while observing actions performed by others. However, resonating with another person's actions is not always an appropriate response: In real life, people do not just imitate but rather respond in a suitable fashion. A growing body of neurophysiologic studies has demonstrated that motor resonance can be overridden by complementary motor responses (such as preparing a precision grip on a small object when seeing an open hand in sign of request). In this study, we investigated the relationship between congruent and incongruent corticospinal activations at the level of multiple effectors. The modulation of motor evoked potentials evoked by single-pulse TMS over the motor cortex was assessed in upper and lower limb muscles of participants observing a soccer player performing a penalty kick straight in their direction. Study results revealed a double dissociation: Seeing the soccer player kicking the ball triggered a motor resonance in the observer's lower limb, whereas the upper limb response afforded by the object was overridden. On the other hand, seeing the ball approaching the observers elicited a complementary motor activation in upper limbs while motor resonance in lower limbs disappeared. Control conditions showing lateral kicks, mimicked kicks, and a ball in penalty area were also included to test the motor coding of object affordances. Results point to a modulation of motor responses in different limbs over the course of action and in function of their relevance in different contexts. We contend that ecologically valid paradigms are now needed to shed light on the motor system functioning in complex forms of interaction.

Prior intentions are abstract mental representations that are believed to be the prime cause of our intentional actions. To date, only a few studies have focused on the possibility that single prior intentions could be identified in people's minds. Here, for the first time, we used the autobiographical Implicit Association Test (aIAT) in order to identify a specific prior intention on the basis of a pattern of associations derived from reaction times (Experiment 1). The aIAT is based on two critical blocks: the block associating intentions with true sentences (congruent block) gave rise to faster reaction times (RTs) than the block associating intentions with false sentences (incongruent block). Furthermore, when comparing intentions with hopes, it was revealed that the reported effect was intention-specific: The pattern of associations reflected a congruency effect when intentions and the logical category “True” were paired, but not when hopes and the “True” category were paired (Experiment 2). Finally, we investigated the neural bases of the congruency effect that leads to the identification of an intention (Experiment 3). We found a reduced late positive component (LPC) for the incongruent with respect to the congruent block, suggesting that the incongruent block needs additional resources of cognitive control with respect to the congruent block.

Previous research has provided evidence for a neural system underlying the observation of another person's hand actions. Is the neural system involved in this capacity also important in inferring another person's motor intentions toward an object from their eye gaze? In real-life situations, humans use eye movements to catch and direct the attention of others, often without any accompanying hand movements or speech. In an event-related functional magnetic resonance imaging study, subjects observed videos showing a human model either grasping a target object (grasping condition) or simply gazing (gaze condition) at the same object. These two conditions were contrasted with each other and against a control condition in which the human model was standing behind the object without performing any gazing or grasping action. The results revealed activations within the dorsal premotor cortex, the inferior frontal gyrus, the inferior parietal lobule, and the superior temporal sulcus in both “grasping” and “gaze” conditions. These findings suggest that signaling the presence of an object through gaze elicits in an observer a similar neural response to that elicited by the observation of a reach-to-grasp action performed on the same object.

Neglect patients often show deficits in responding to targets in the contralesional side of space. Past studies were able to ameliorate these deficits through manipulation of visual input. Here, the neural bases of the recovery of space following virtual reality (VR) training in neglect patients were investigated. Neglect patients were trained to respond to targets in the left side of space that appeared in the central or in the right side of space in a VR system. It was found that only patients with lesions that spared the inferior parietal/superior temporal regions were able to benefit from the VR training. It was concluded that these regions play a crucial role in the recovery of space that underlies the improvement of neglect patients when trained with VR. The implications of these results for determining the neural bases of a higher order attentional and/or spatial representation and for treating patients with unilateral neglect are discussed.

The aims of the present study were to investigate whether the processing of an object shadow occurs implicitly, that is without conscious awareness, and where physically within the human brain shadows are processed. Here we present neurological evidence, obtained from studies of brain-injured patients with visual neglect, that shadows are implicitly processed and that this processing may take place within the temporal lobe. Neglect patients with lesions that do not involve the right temporal lobe were still able to process shadows to optimize object shape perception. In contrast, shadow processing was not found to be as efficient in neglect patients with lesions that involve the right temporal lobe.