Referential pointing is a characteristically human behavior, which involves moving a nger through space to direct an addressee towards a desired mental state. Planning this type of action requires an interface between sensorimotor and conceptual abilities. A simple interface could supplement spatially-guided motor routines with communicative-ostensive cues. For instance, a pointing nger held still for […]
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We share our thoughts with other minds, but we do not understand how. Having a common language certainly helps, but infants’ and tourists’ communicative success clearly illustrates that sharing thoughts does not require signals with a pre-assigned meaning. In fact, human communicators jointly build a fleeting conceptual space in which signals are a means to […]
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How do object perception and action interact at a neural level? Here we test the hypothesis that perceptual features, processed by the ventral visuoperceptual stream, are used as priors by the dorsal visuomotor stream to specify goal-directed grasping actions. We present three main findings, which were obtained by combining time-resolved transcranial magnetic stimulation and kinematic […]
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The great promise of comparative neuroscience is to understand why brains differ by investigating the relations between variations in the organization of different brains, their evolutionary history, and their current ecological niche. For this approach to be successful, the organization of different brains needs to be quantifiable. Here, we present an approach to formally comparing […]
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We compared the course and cortical projec- tions of white matter fibers passing through the extreme capsule in humans and macaques. Previous comparisons of this tract have suggested a uniquely human posterior pro- jection, but these studies have always employed different techniques in the different species. Here we used the same technique, diffusion MRI, in […]
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Correlations in brain activity between two areas (functional connectivity) have been shown to relate to their underlying structural connections. We examine the possibility that functional connectivity also reflects short-term changes in synaptic efficacy. We demonstrate that paired transcranial magnetic stimulation (TMS) near ventral premotor cortex (PMv) and primary motor cortex (M1) with a short 8-ms […]
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How can we understand each other during communicative inter- actions? An influential suggestion holds that communicators are primed by each other’s behaviors, with associative mechanisms au- tomatically coordinating the production of communicative signals and the comprehension of their meanings. An alternative sugges- tion posits that mutual understanding requires shared conceptuali- zations of a signal’s use, […]
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Primate comparative anatomy is an established field that has made rich and substantial contributions to neuroscience. However, the labor-intensive techniques employed mean that most comparisons are often based on a small number of species, which limits the conclusions that can be drawn. In this review we explore how new developments in magnetic resonance imaging have […]
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Despite the ambiguity inherent in human communication, people are remarkably efficient in establishing mutual understanding. Studying how people communicate in novel settings provides a window into the mechanisms supporting the human competence to rapidly generate and understand novel shared symbols, a fundamental property of human communication. Previous work indicates that the right posterior superior temporal […]
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Human referential communication is often thought as coding– decoding a set of symbols, neglecting that establishing shared meanings requires a computational mechanism powerful enough to mutually negotiate them. Sharing the meaning of a novel sym- bol might rely on similar conceptual inferences across communica- tors or on statistical similarities in their sensorimotor behaviors. Using magnetoencephalography, […]
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After a threatening event, the risk of developing social psychopathologies is increased in short-allele (s) carriers of the serotonin trans- porter gene. The amygdala becomes overresponsive to emotional stimuli, an effect that could be driven by local hypersensitivity or by reduced prefrontal regulation. This study distinguishes between these two hypotheses by using dynamic causal modeling […]
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Passingham and Wise (2012) set out to understand the organization and func- tion of the primate PFC by combining evolutionary and ecological perspectives. Large parts of PFC, and specifically those with a granular cortical layer, are a pri- mate invention. The authors argue that the development of these areas reflects the changes in foraging niches […]
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Two parietofrontal networks share the control of goal-directed movements: a dorsomedial circuit that includes the superior parieto- occipital sulcus (sPOS) and a dorsolateral circuit comprising the anterior intraparietal sulcus (aIPS). These circuits are thought to independently control either reach and grip components (a functional dissociation), or planning and execution phases of grasping movements (a temporal […]
moreOur sensorimotor interactions with objects are guided by their current spatial and perceptual features, as well as by learned object knowledge. A fresh red tomato is grasped differently than a soft overripe tomato, even when those objects possess the same spatial metrics of size and shape. Objects’ spatial and perceptual features need to be integrated […]
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How to grasp a ripe tomato? Fortunately, we don’t have to think about this when we are standing in the supermarket after a busy day. We carefully grasp that ripe tomato without effort. Such a fluent integration of abstract knowledge (“that tomato is ripe”) and spatial information (“it is there”) is actually extraordinary. While modern […]
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When dealing with emotional situations, we often need to rapidly override automatic stimulus-response mappings and select an alternative course of action [1], for instance, when trying to manage, rather than avoid, another’s aggres- sive behavior. The anterior prefrontal cortex (aPFC) has been linked to the control of these social emotional behav- iors [2, 3]. We […]
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It is clear that the steroid hormone testosterone plays an important role in the regulation of social emotional behavior, but it remains unknown which neural circuits mediate these hormonal influences in humans. We investigated the modulatory effects of endogenous testosterone on the control of social emotional behavior by applying functional magnetic resonance imaging while healthy […]
morePrevious studies of learned bird song have suggested the existence of species-universal patterns in song organization: clear clusters in produced songs that do not vary within a species. Here the authors combine a computational method of comparing songs with statistical methods of assessing cluster structure to investigate this issue in a more quantitative manner. The […]
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In the well-known rubber hand illusion (RHI), watching a rubber hand being stroked while one’s own unseen hand is synchronously stroked, induces a relocation of the sensed position of one’s own hand towards the rubber hand. As one has lost the veridical location of one’s hand, one should not be able to correctly guide one’s […]
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In the rubber hand illusion (RHI), participants incorporate a rubber hand into a mental representation of one’s body. This deceptive feeling of ownership is accompanied by recalibration of the perceived position of the participant’s real hand toward the rubber hand. Neuroimaging data suggest involvement of the posterior parietal lobule during induction of the RHI, when […]
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Adaptive behavior relies on the integration of perceptual and motor processes. In this study, we aimed at characterizing the cerebral processes underlying perceptuo-motor interactions evoked during prehension movements in healthy humans, as measured by means of functional magnetic resonance imaging. We manipulated the viewing conditions (binocular or monocular) during planning of a prehen- sion movement, […]
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Grasping an object requires processing visuospatial information about the extrinsic features (spatial location) and intrinsic features (size, shape, orientation) of the object. Accordingly, manual prehension has been subdivided into a reach component, guiding the hand toward the object on the basis of its extrinsic features, and a grasp component, preshaping the fingers around the center […]
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To interact effectively with our environment, we need to specify the intended outcomes (goals) of our actions. In this process, immediate goals and final goals can be regarded as different levels within a hierarchically organized system for action planning: immediate goals and movement details are selected to accomplish more remote goals. Behavioral studies support this […]
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