Recognition at the Heart of the Complex Situations Experienced by People With Chronic Musculoskeletal Pain.

Objective: Chronic musculoskeletal pain (CMSP) is frequent in chronic diseases, decreasing the quality of life of these patients. In a survey conducted in Belgium in 2019, chronic pain was named by patients as the main factor of complexity in their lives. The objective of our research was to provide elements to understand why and how CMSP contributes to the complexity of these people's lives.

Behavioral therapy in migraine: Expanding the therapeutic arsenal.

Background And Purpose: The US Headache Consortium developed evidence-based guidelines for the treatment of migraine and found grade A evidence in support of behavior therapy (BT). Understanding the mechanisms of BT may improve the management of migraine and reduce its burden.

Methods: We performed a narrative review to define the current evidence of BT and determine its usefulness in migraine management.

Validity and reliability testing of the Spanish version of the BESTest and mini-BESTest in healthy community-dwelling elderly.

Background: The Balance Evaluation Systems Test (BESTest) and its abbreviated version, the Mini-BESTest are clinical examination of balance impairment, but its psychometric properties have not yet been tested in European Spanish. We aimed to assess the psychometric properties of BESTest and Mini-BESTest in Spanish in community-dwelling elderly people.

Methods: We designed a cross-sectional transcultural adaptation and validation study.

Physiological modules for generating discrete and rhythmic movements: component analysis of EMG signals.

A central question in Neuroscience is that of how the nervous system generates the spatiotemporal commands needed to realize complex gestures, such as handwriting. A key postulate is that the central nervous system (CNS) builds up complex movements from a set of simpler motor primitives or control modules. In this study we examined the control modules underlying the generation of muscle activations when performing different types of movement: discrete, point-to-point movements in eight different directions and continuous figure-eight movements in both the normal, upright orientation and rotated 90°.

Physiological modules for generating discrete and rhythmic movements: action identification by a dynamic recurrent neural network.

In this study we employed a dynamic recurrent neural network (DRNN) in a novel fashion to reveal characteristics of control modules underlying the generation of muscle activations when drawing figures with the outstretched arm. We asked healthy human subjects to perform four different figure-eight movements in each of two workspaces (frontal plane and sagittal plane). We then trained a DRNN to predict the movement of the wrist from information in the EMG signals from seven different muscles.

Gravity influences top-down signals in visual processing.

Visual perception is not only based on incoming visual signals but also on information about a multimodal reference frame that incorporates vestibulo-proprioceptive input and motor signals. In addition, top-down modulation of visual processing has previously been demonstrated during cognitive operations including selective attention and working memory tasks. In the absence of a stable gravitational reference, the updating of salient stimuli becomes crucial for successful visuo-spatial behavior by humans in weightlessness.

Biological oscillations for learning walking coordination: dynamic recurrent neural network functionally models physiological central pattern generator.

The existence of dedicated neuronal modules such as those organized in the cerebral cortex, thalamus, basal ganglia, cerebellum, or spinal cord raises the question of how these functional modules are coordinated for appropriate motor behavior. Study of human locomotion offers an interesting field for addressing this central question. The coordination of the elevation of the 3 leg segments under a planar covariation rule (Borghese et al.

Weightlessness alters up/down asymmetries in the perception of self-motion.

In the present study, we investigated the effect of weightlessness on the ability to perceive and remember self-motion when passing through virtual 3D tunnels that curve in different direction (up, down, left, right). We asked cosmonaut subjects to perform the experiment before, during and after long-duration space flight aboard the International Space Station (ISS), and we manipulated vestibular versus haptic cues by having subjects perform the task either in a rigidly fixed posture with respect to the space station or during free-floating, in weightlessness. Subjects were driven passively at constant speed through the virtual 3D tunnels containing a single turn in the middle of a linear segment, either in pitch or in yaw, in increments of 12.

Optimal walking speed following changes in limb geometry.

The principle of dynamic similarity states that the optimal walking speeds of geometrically similar animals are independent of size when speed is normalized to the dimensionless Froude number (Fr). Furthermore, various studies have shown similar dimensionless optimal speed (Fr ∼0.25) for animals with quite different limb geometries.

Movement gating of beta/gamma oscillations involved in the N30 somatosensory evoked potential.

Evoked potential modulation allows the study of dynamic brain processing. The mechanism of movement gating of the frontal N30 component of somatosensory evoked potentials (SEP) produced by the stimulation of the median nerve at wrist remains to be elucidated. At rest, a power enhancement and a significant phase-locking of the electroencephalographic (EEG) oscillation in the beta/gamma range (25-35 Hz) are related to the emergence of the N30.

Pure phase-locking of beta/gamma oscillation contributes to the N30 frontal component of somatosensory evoked potentials.

Background: Evoked potentials have been proposed to result from phase-locking of electroencephalographic (EEG) activities within specific frequency bands. However, the respective contribution of phasic activity and phase resetting of ongoing EEG oscillation remains largely debated. We here applied the EEGlab procedure in order to quantify the contribution of electroencephalographic oscillation in the generation of the frontal N30 component of the somatosensory evoked potentials (SEP) triggered by median nerve electrical stimulation at the wrist.

Recognition of the physiological actions of the triphasic EMG pattern by a dynamic recurrent neural network.

Triphasic electromyographic (EMG) patterns with a sequence of activity in agonist (AG1), antagonist (ANT) and again in agonist (AG2) muscles are characteristic of ballistic movements. They have been studied in terms of rectangular pulse-width or pulse-height modulation. In order to take into account the complexity of the EMG signal within the bursts, we used a dynamic recurrent neural network (DRNN) for the identification of this pattern in subjects performing fast elbow flexion movements.

Two reference frames for visual perception in two gravity conditions.

The processing and storage of visual information concerning the orientation of objects in space is carried out in anisotropic reference frames in which all orientations are not treated equally. The perceptual anisotropies, and the implicit reference frames that they define, are evidenced by the observation of 'oblique effects' in which performance on a given perceptual task is better for horizontally and vertically oriented stimuli. The question remains how the preferred horizontal and vertical reference frames are defined.

Gait control in spinal palsy.

Developmental motor impairment with lower limb spasticity most commonly corresponds to cerebral palsy of the spastic diplegia type. Here we describe a 4-year-old girl whose locomotor phenotype reflects early cortico-spinal lesion at the spinal level. This child has developmental spastic paraparesis secondary to D4-D8 cord compression.