Research topics - Valery Legrain

Research projects

Temporal order judgment tasks to characterize the “neglect-like” deficits of CRPS

Investigators : Lieve Filbrich, Valery Legrain.

Adequately responding to a painful stimulus requires knowing where pain is localized on the body, but also where the cause of pain is localized in the external world. This involves for the brain to coordinate the somatotopic representation of the body and the representations of the space around the body. According to a recent theory, the spatial localization of pain depends on a cortical mapping system that integrates nociceptive (localization of the salient and threatening stimulus on the body), proprioceptive (localization of the limbs in external space) and visual information (localization of the cause/source of pain in the external world) into a multimodal and peripersonal representation of the body and the space nearby. The aim of this project is to strengthen this theory by investigating, in patients suffering from complex regional pain syndrome (CRPS), how pain in one limb affects the representation of the space surrounding the body. More specifically, using behavioral measures (temporal order judgment tasks), we characterize the “neglect-like” deficits of CRPS patients in perceiving the spatial location of visual stimuli occurring close to the body. Findings will help to understand how pain is integrated in a peripersonal representation of the body and the space nearby. They could also have an important impact on the understanding and the rehabilitation of chronic pain.

Prism adaptation to alleviate pain and improve functional outcome in unilateral chronic pain

Investigators : Samar Hatem, André Mouraux, Valery Legrain.

This research project aims at (1) characterizing cognitive deficits similar to hemispatial neglect in unilateral chronic pain patients by examining the interactions between pain and visuospatial perception, (2) assessing the efficacy of prism adaptation as an original non-pharmacological approach to alleviate pain and to improve the functional outcome in unilateral chronic pain and (3) characterizing the changes in brain morphology induced by prism adaptation using high resolution MRI.

How visual experience influences the perception of nociceptive stimuli and pain

In this project, we investigate how visual experience influences the perception of nociceptive stimuli and pain. Specifically, we compare the cognitive abilities of people with congenital blindness and those of normal sighted people to localize nociceptive stimuli on the body space.

Neurophysiological mechanisms underlying visual-nociceptive integration in the representation of the body and the peripersonal space

This research project investigates the neurophysiological mechanisms underlying visual-nociceptive integration in the representation of the body and the peripersonal space. More specifically, the recording of steady state evoked brain potentials is used to explore how nociceptive stimulation affects the processing of external visual stimuli in order to form a meaningful multimodal representation of physical threats.

Cognitive resources required for the planning and online control of fine object manipulation

Investigators : Erwan Guillery, Jean-Louis Thonnard, André Mouraux, Valery Legrain.

In everyday life, object manipulation is among the most common tasks we perform and is usually performed concurrently to the execution of cognitive tasks. In athis project, we study the mental resources required for the planning and online control of fine upper-limb movement. Specifically, we use a novel motor-cognitive dual-task paradigm to examine the influence of a cognitive task on the different aspects of precision grip in elders and in patients presenting with a peripheral or central lesion of the nervous system.

The role of working memory in the attentional control for pain

Investigators : Valery Legrain, André Mouraux.

Disengaging attention away from a nociceptive stimulus has been shown to effectively reduce pain. However, because pain signals the occurrence of potential tissue damage, nociceptive stimuli are prompt to capture attention despite voluntary control. A recent model stresses that an effective attentional control of pain does not simply imply the disengagement of attention, but depends also on cognitive factors that guarantee that attention is maintained on the processing of pain-unrelated information without being recaptured by nociceptive stimuli. Supporting this view, experiments have shown that the ability of nociceptive stimuli to capture attention can be modulated by top-down factors. In this frame, we have explored the involvement of working memory in the control of the attentional capture by nociception. Working memory is involved in the short-term maintaining and storing of information for its immediate manipulation, and has been suggested to regulate the top-down control of attention by maintaining current processing priorities during task performance. Through a series of psychophysical experiments, we found that engaging subjects in a task involving working memory significantly reduces the distraction induced by nociceptive stimuli. Furthermore, using EEG, we found that engaging working memory reduces the magnitude of early-latency responses to the nociceptive stimulus, indicating an effect already at the earliest stages of nociceptive processing. Taken together, the present results suggest that cognitive strategies involving working memory to shield cognition from nociception could be used to alleviate pain.