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Abstract: When interacting with the world, we need to distinguish whether sensory information results from external events or from our own actions. The nervous system most likely draws this distinction by comparing the actual sensory input with an internal prediction about the sensory consequences of one’s actions. However, interacting with the world also requires an evaluation of the outcomes of self-action, e.g. in terms of their affective valence. Here we show that subjects’ perceived pointing direction does not only depend on predictive and sensory signals related to the performed action itself, but also on the affective valence of the action outcome: subjects perceived their movements as directed towards positive and away from negative outcomes. Our findings suggest that the non-conceptual perception of the sensory consequences of self-action builds on both sensorimotor information related directly to self-action and a post hoc evaluation of the affective action outcome. [Copyright &y& Elsevier]

Abstract: Clinical data indicate that the brain network of speech motor control can be subdivided into at least three functional–neuroanatomical subsystems: (i) planning of movement sequences (premotor ventrolateral–frontal cortex and/or anterior insula), (ii) preparedness for/initiation of upcoming verbal utterances (supplementary motor area, SMA), and (iii) on-line innervation of vocal tract muscles, i.e., motor execution (corticobulbar system, basal ganglia, cerebellum). Using an event-related design, this functional magnetic resonance imaging (fMRI) study sought to further delineate the contribution of SMA to pre-articulatory processes of speech production (preceding the innervation of vocal tract muscles) during an acoustically paced syllable repetition task forewarned by a tone signal. Hemodynamic activation across the whole brain and the time courses of the responses in five regions of interest (ROIs) were computed. First, motor preparation was associated with a widespread bilateral activation pattern, encompassing brainstem structures, SMA, insula, premotor ventrolateral–frontal areas, primary sensorimotor cortex (SMC), basal ganglia, and the superior cerebellum. Second, calculation of the time courses of BOLD (“blood oxygenation level-dependent”) signal changes revealed the warning stimulus to elicit synchronous onset of hemodynamic activation in these areas. However, during 4-s intervals of syllable repetitions SMA and cerebellum showed opposite temporal activation patterns in terms of a shorter (SMA) and longer (cerebellum) latency of the entire BOLD response—as compared to SMC, indicating different pacing mechanisms during the initial and the ongoing phase of the task. Nevertheless, the contribution of SMA was not exclusively restricted to the preparation/initiation of verbal responses since the extension of mesiofrontal activation varied with task duration. [Copyright &y& Elsevier]