Search results for "motor execution"
showing 5 items of 5 documents
Dissociating effect of upper limb non-use and overuse on space and body representations.
2015
Accurate and updated representations of the space where the body acts, i.e. the peripersonal space (PPS), and the location and dimension of body parts (body representation, BR) are essential to perform actions. Because both PPS and BR are involved in motor execution and display the same plastic proprieties after the use of a tool to reach far objects, it has been suggested that they overlap in a unique representation of the body in a space devoted to action. Here we determined whether manipulating actions in space, without modifying body metrics, i.e. through immobilization, induces a dissociation of the plastic properties of PPS and BR. In 39 healthy subjects we evaluated PPS and BR for th…
An investigation of the neural circuits underlying reaching and reach-to-grasp movements: from planning to execution
2014
Experimental evidence suggests the existence of a sophisticated brain circuit specifically dedicated to reach-to-grasp planning and execution, both in human and non-human primates (Castiello, 2005). Studies accomplished by means of neuroimaging techniques suggest the hypothesis of a dichotomy between a "reach-to-grasp" circuit, involving the anterior intraparietal area, the dorsal and ventral premotor cortices (PMd and PMv - Castiello and Begliomini, 2008; Filimon, 2010) and a "reaching" circuit involving the medial intraparietal area and the superior parieto-occipital cortex (Culham et al., 2006). However, the time course characterizing the involvement of these regions during the planning …
Temporal-range estimation of multiple objects: evidence for an early bottleneck.
2011
When making parallel time-to-contact (TTC) estimates of two approaching objects, the two respective TTC estimates interfere with one another in an asymmetric fashion. The TTC of the later-arriving object is systematically overestimated, while the estimated TTC for the first-arriving object is as accurate as in a condition presenting only a single object. This asymmetric interference points to a processing bottleneck that could be due to early (e.g., during the estimation of the TTC from the optic flow) or late (e.g., during the timing of the response or the motor execution) constraints in the TTC estimation process. We used a Sperling-like prediction-motion task to differentiate between the…
Low intensity magnetic field influences short-term memory: A study in a group of healthy students
2015
This study analyzes if an external magnetic stimulus (2 kHz and approximately 0.1 μT applied near frontal cortex) influences working memory, perception, binary decision, motor execution, and sustained attention in humans. A magnetic stimulus and a sham stimulus were applied to both sides of the head (frontal cortex close to temporal-parietal area) in young and healthy male test subjects (n = 65) while performing Sternberg's memory scanning task. There was a significant change in reaction time. Times recorded for perception, sustained attention, and motor execution were lower in exposed subjects (P < 0.01). However, time employed in binary decision increased for subjects exposed to magnetic …
Motor imagery and cortico-spinal excitability: A review
2016
International audience; Motor imagery (MI) has received a lot of interest during the last decades as its chronic or acute use has demonstrated several effects on improving sport performances or skills. The development of neuroimagery techniques also helped further our understanding of the neural correlates underlying MI. While some authors showed that MI, motor execution and action observation activated similar motor cortical regions, transcranial magnetic stimulation (TMS) studies brought great insights on the role of the primary motor cortex and on the activation of the cortico-spinal pathway during MI. After defining MI and describing the TMS technique, a short report of MI activities on…