Prism adaptation effects in complex regional pain syndrome: A therapo-physiological single case experimental design exploratory report.

Complex Regional Pain Syndrome (CRPS) is an invalidating chronic condition that can occur after an acute peripheral lesion. Prism adaptation therapy is regarded as a promising tool to improve chronic pain in this syndrome but the mechanisms which lead to pain amelioration remain unknown. In this exploratory report we performed a retrospective analysis of longitudinal data collected from a single, atypical patient, who showed hyper-attention toward her affected (left) hand. Repeated assessments of pain and spatial neglect made during the course of the prism adaptation treatment revealed differential contributions of the two hands to adaptation-induced pain reduction. Treatment response appeared to be associated with a relative modification of the spatial behaviour of the two hands. This case study provides a new example of pain relief following prismatic deviation away from the pathological side.

[Impact of pharmaceutical interventions on antibiotic therapy of urinary tract infections in rehabilitation center]. / Impact des interventions pharmaceutiques sur l'antibiothérapie des infections urinaires en service de soins de suite et de réadaptation.

BACKGROUND: The aim of this study was to assess the impact of medico-pharmaceutical partnership on the quality of antibiotic treatment in urinary tract infection (UTI) within rehabilitation center. MATERIAL: All antibiotic prescriptions were validated by the pharmacist at the start of treatment and twice a week. All patients with symptomatic urinary tract infection between January 1, 2014 to December 31, 2015 were included in this study. Addition to awareness among specifiers to promoting the appropriate use of antibiotics, the pharmacist suggested pharmaceutical interventions (PI) in order to improve the quality of antibiotic treatments. At the same time, 3 quality indicators (QI) were followed: duration, dosage, antibiotic susceptibility. The compliance rates of this 3 QI allowed to assess the quality of the antibiotic treatment in urinary tract infection. RESULTS: The study population included 154 patients corresponding to 252 UTI. Sixty-eight PI were made by pharmacist about urinary tract infection treatment (overdosage or under-dosing, duration unknown, inadequate route of administration). These QI achieved 96.4% compliance with duration, 98.8% compliance with dosage and 99.2% with the antibiotic susceptibility. CONCLUSION: This study allowed showing the medico-pharmaceutical impact on the quality of antibiotic treatments in UTI. The awareness among specifiers with a daily validation of prescription by the pharmacist allowed to improve urinary tract infections care in rehabilitation center. LEVEL OF EVIDENCE: 4.

Bladder dysfunction in hereditary spastic paraplegia: a clinical and urodynamic evaluation.

OBJECTIVES: Hereditary spastic paraplegia (HSP) is a degenerative central nervous system disorder characterized by progressive spasticity and hyperreflexia of the lower limbs. Often, patients with HSP experience symptoms of voiding dysfunction. Urodynamic evaluations of these patients are rarely reported in the literature and the etiology of voiding dysfunction remains unclear. The present study characterizes lower urinary tract dysfunction in a large series of patients. METHODS: The medical records of 29 HSP patients who underwent urodynamic evaluation were retrospectively analyzed. The history of lower urinary tract symptoms was noted and the urodynamic findings analyzed. RESULTS: Urgency was the most dominant complaint (72.4%), followed by frequency (65.5%), urinary incontinence (55.2%) and hesitancy (51.7%). The urodynamic findings showed signs of central neurogenic bladder in 24 patients (82.7%), with detrusor overactivity (DO) in 15 patients (51.7%) and detrusor sphincter dyssynergia (DSD) in 19 (65.5%). Post-void residual (PVR) of >10% of the voided volume was found in 12 patients (41.4%). There were significant relationships between detrusor overactivity and PVR (P=0.005), frequency (P=0.046) and nocturia (P=0.045). Ultrasound examination revealed no upper urinary tract complications. CONCLUSION: Despite the presence of DO and DSD, HSP patients do not seem to have a high risk of developing ultrasonographically-assessed upper urinary tract complications after a mean follow-up of 22 years, contrary to spinal cord injury population. These results may guide practitioners in their decision-making about the appropriate evaluation and treatment of bladder disturbances that accompany hereditary spastic paraplegia.

[Importance of cognitive disorders in internal medicine: Pathophysiology, diagnosis, management. The example of systemic lupus erythematosus]. / Importance des troubles cognitifs en médecine interne : physiopathologie, évaluation, prise en charge. L'exemple du lupus systémique.

Systemic diseases, which are in France mainly monitored in internal medicine, affect multiple organs or tissues. While cutaneous or articular manifestations are the most common, neurological involvement is often associated with severity. Diagnosis of peripheral (e.g, neuropathies) or central (e.g, myelitis) nervous disorders is quite easy through clinical examination and dedicated complementary tests. However, neuropsychological manifestations that affect cognition, including memory, attention, executive functions or reasoning, are difficult to diagnose, sometimes trivialized by practitioners. Their causes are often numerous and interrelated. Nevertheless, these cognitive manifestations are closely related to patients' quality of life, affecting their social life, family dynamics and professional integration but also the treatment adherence. The purpose of this review, focused on the example of systemic lupus erythematosus, is to raise awareness of cognitive dysfunction in systemic diseases including their management from diagnosis to treatments. The final aim is to go further into setting up research groups and care programs for patients with cognitive impairment followed in internal medicine.

Effect of prism adaptation on left dichotic listening deficit in neglect patients: glasses to hear better?

Unilateral neglect is a disabling syndrome frequently observed following right hemisphere brain damage. Symptoms range from visuo-motor impairments through to deficient visuo-spatial imagery, but impairment can also affect the auditory modality. A short period of adaptation to a rightward prismatic shift of the visual field is known to improve a wide range of hemispatial neglect symptoms, including visuo-manual tasks, mental imagery, postural imbalance, visuo-verbal measures and number bisection. The aim of the present study was to assess whether the beneficial effects of prism adaptation may generalize to auditory manifestations of neglect. Auditory extinction, whose clinical manifestations are independent of the sensory modalities engaged in visuo-manual adaptation, was examined in neglect patients before and after prism adaptation. Two separate groups of neglect patients (all of whom exhibited left auditory extinction) underwent prism adaptation: one group (n = 6) received a classical prism treatment ('Prism' group), the other group (n = 6) was submitted to the same procedure, but wore neutral glasses creating no optical shift (placebo 'Control' group). Auditory extinction was assessed by means of a dichotic listening task performed three times: prior to prism exposure (pre-test), upon prism removal (0 h post-test) and 2 h later (2 h post-test). The total number of correct responses, the lateralization index (detection asymmetry between the two ears) and the number of left-right fusion errors were analysed. Our results demonstrate that prism adaptation can improve left auditory extinction, thus revealing transfer of benefit to a sensory modality that is orthogonal to the visual, proprioceptive and motor modalities directly implicated in the visuo-motor adaptive process. The observed benefit was specific to the detection asymmetry between the two ears and did not affect the total number of responses. This indicates a specific effect of prism adaptation on lateralized processes rather than on general arousal. Our results suggest that the effects of prism adaptation can extend to unexposed sensory systems. The bottom-up approach of visuo-motor adaptation appears to interact with higher order brain functions related to multisensory integration and can have beneficial effects on sensory processing in different modalities. These findings should stimulate the development of therapeutic approaches aimed at bypassing the affected sensory processing modality by adapting other sensory modalities.

Can you guess the colour of this moving object? A dissociation between colour and motion in blindsight.

Blindsight has been primarily and extensively studied by Lawrence Weiskrantz. Residual visual abilities following a hemispheric lesion leading to homonymous hemianopia encompass a variety of visual-perceptual and visuo-motor functions. Attention blindsight produces the more salient subjective experiences, especially for motion (Riddoch phenomenon). Action blindsight illustrates visuo-motor abilities despite the patients' feeling that they produce random movements. Perception blindsight seems to be the weakest residual function observed in blindsight, e.g. for wavelength sensitivity. Discriminating motion produced by isoluminant colours does not give rise to blindsight for motion but the outcome of the reciprocal test is not known. Here we tested whether moving stimuli could give rise to colour discrimination in a patient with homonymous hemianopia. It was found that even though the patient exhibited nearly perfect performances for motion direction discrimination his colour discrimination for the same moving stimulus remained at chance level. It is concluded that easily discriminated moving stimuli do not give rise to colour discrimination and implications for the 3 levels of blindsight taxonomy are discussed.

Construction and feasibility study of the SOFMER Activity Score (SAS), a new assessment of physical and cognitive activity.

OBJECTIVES: For hospitalizations in rehabilitation centers (RCs) in France, the quantification of healthcare givers' activity is based on the dependency of the patients, defined as a total or partial inability to perform activities required for daily living without help. The tools currently used to quantify dependency are not sufficiently precise. Here we describe the construction of a new tool, the SOFMER Activity Score (SAS scoring), which allows for a good description of the level of activity of patients hospitalized in RCs, and a feasibility study of the tool. METHODS: After a study group proposed the first version of the SAS, the validity of its content was studied by the Delphi consensus method: 26 physicians or healthcare professionals known for their expertise in PMR responded to the first round. The feasibility study was prospective and involved multi-site professionals. Data related to the SAS determined by a multidisciplinary team were collected and compared to the Activité de la Vie Quotidienne (AVQ) scale, which is administered to all patients and included in medical and administrative data. RESULTS: We included 81 patients in the feasibility study. The mean (SD) time to obtain the SAS was 4.5 (3.3) min. For 97.5% of scorings, the participating professionals judged that the SAS was compatible or fairly compatible with clinical practice. The internal structure of the SAS scale seemed better than that of the AVQ scale, for which the present study confirmed a floor effect for all items. CONCLUSIONS: The SAS allows for measuring the level of physical and cognitive activity of a patient hospitalized in an RC. If validation studies for the SAS, exploring its reliability, construct validity or criterion validity, confirm the tool's good metrological qualities, the SAS will allow for a good quantification of the burden of care.

[Assessment of disability and quality of life in patients with cognitive disorders]. / Evaluation des incapacités et de la qualité de vie des patients présentant des troubles cognitifs.

OBJECTIVE: To identify disability, handicap and quality of life questionnaires available for patients with cognitive impairment. MATERIALS AND METHODS: We systematically reviewed the literature in Medline using the keywords assessment, evaluation, deficiency, disability, disadvantage, handicap, quality of life, scale, index, questionnaire, ICIDH-1, and ICIDH-2, combined with the cognitive deficits dysexecutive syndrome, memory deficits, attention deficits, neglect, apraxia, aphasia, agnosia and mood disorders. We focused on validated scales and distinguished scales dedicated to assess disability, handicap and quality of life. RESULTS: At the level of disability, global and specific scales are available. Specific scales exist for dysexecutive syndrome, memory deficits, attention deficits, unilateral neglect, aphasia and mood disorders. French adaptations of foreign language tests and original tests developed in French have been validated in these areas. No specific tool is available for isolated apraxia or agnosia. Generic scales and pathology-specific scales (for stroke, traumatic brain injury, and multiple sclerosis) are available for quality of life. For aphasia, specific tools are available for incapacity handicap and quality of life. CONCLUSION: Previous results show the impact of the ICIDH-1 framework on functional outcome assessment of cognitive impairments. This approach is often limited by the lack of theoretical background and by the difficulty to assess the involvement of environment and anosognosia.

Hemi-spatial neglect rehabilitation using non-invasive brain stimulation: or how to modulate the disconnection syndrome?

Hemi-spatial neglect syndrome is common and sometimes long-lasting. It is characterized by a deficit in the use and awareness of one side of space, most often consecutive to a right hemisphere injury, mainly in the parietal region. Acknowledging the different types and all clinical characteristics is essential for an appropriate evaluation and adapted rehabilitation care management, especially as it constitutes a predictive factor of a poor functional prognosis. Some new approaches have been developed in the last fifteen years in the field of hemi-spatial neglect rehabilitation, where non-invasive brain stimulation (TMS and tDCS) holds an important place. Today's approaches of unilateral spatial neglect modulation via non-invasive brain stimulation are essentially based on the concept of inter-hemispheric inhibition, suggesting an over-activation of the contralesional hemisphere due to a decrease of the inhibiting influences of the injured hemisphere. Several approaches may then be used: stimulation of the injured right hemisphere, inhibition of the hyperactive left hemisphere, or a combination of both. Results are promising, but the following complementary aspects must be refined before a more systematic application: optimal stimulation protocol, individual management according to the injured region, intensity, duration and frequency of care management, delay post-stroke before the beginning of treatment, combination of different approaches, as well as prognostic and efficacy criteria. An encouraging perspective for the future is the combination of several types of approaches, which would be largely facilitated by the improvement of fundamental knowledge on neglect mechanisms, which could in the future refine the choice for the most appropriate treatment(s) for a given patient.

Long-term sensorimotor and therapeutical effects of a mild regime of prism adaptation in spatial neglect. A double-blind RCT essay.

Spatial neglect (SN) is commonly associated with poor functional outcome. Adaptation to a rightward optical deviation of vision has been shown to benefit to SN rehabilitation. The neurophysiological foundations and the optimal modalities of prism adaptation (PA) therapy however remain to be validated. This study is aimed at exploring the long-term sensory-motor, cognitive and functional effects produced by weekly PA sessions over a period of four weeks. A double-blind, monocentric randomized and controlled trial (RCT) was carried out. Twenty patients with left SN secondary to stroke were included, 10 in the "prism" group and 10 in the "control" group. The sensory-motor effects of PA were evaluated by measurement of manual and visual straight-ahead, and also by precision of pointing without visual feedback before and after each PA session. The functional independence measure (FIM) was evaluated before and at 1, 3 and 6 months after PA, while SN severity was assessed using the Behavioural Inattention Test (BIT) before and 6 months after PA. Before the intervention, only manual straight-ahead pointing constituted a reproducible sensory-motor measurement. During prism exposure, a questionnaire showed that not a single patient were aware of the direct effects of optical deviation on pointing movement performance. The sensory-motor after-effects produced by the PA produced a more rapid reduction of the rightward manual straight-ahead, which was secondarily followed by visual straight-ahead. These sensory-motor effects helped to clarify the action mechanisms of PA on SN. At the conclusion of the 6-month follow-up, the two groups showed similar improvement, indicating that a weekly PA session over 4 weeks was not sufficient to produce long-term functional benefit. This improvement was correlated with the evolution of visual straight-ahead, which can be proposed as a marker for patients outcome.

[Treatment of focal upper limb spasticity with botulinum toxin after stroke. Interest of an individual approach]. / Traitement de la spasticité focale du membre supérieur par toxine botulinique après accident vasculaire cérébral (AVC). Intérêt d'une approche au cas par cas.

INTRODUCTION: It is now demonstrated that botulinum toxin can improve upper limb spasticity after stroke. OBJECTIVES: This study was designed to assess the efficacy of botulinum toxin on upper limb spasticity with an individual approach. METHODS: Prospective study on 18 patients who had disabling spasticity of upper limb after stroke. For each patient, the treatment's target was fixed preliminary to botulinum toxin injection. Evaluation of efficacy (Ashworth scale and predefined targets) was performed at 1 month and treatment continuation was decided individually. RESULTS: A beneficial effect was reported by most patients when the treatment was aimed at improving comfort or quality of life. In one case, the treatment was designed to improve grasping. In that case, no effect was reported. For three patients, a neurotomy was performed in order to obtain a long lasting effect. For nine patients, repeated injections were decided. For the six other patients, no long-standing treatment was performed. DISCUSSION: This study confirms that botulinum toxin can improve comfort of patients with upper limb spasticity. On the base of our experience, we discussed contribution of botulinum toxin to enhance and optimise strategies for the treatment of focal upper limb spasticity with emphasis on the comparison with selective neurotomy.

The motor function measure to study limitation of activity in children and adults with Charcot-Marie-Tooth disease.

OBJECTIVE: To study the applicability and responsiveness of the motor function measure (total score and sub-scores D1, D2 and D3) in patients with Charcot-Marie-Tooth disease. PATIENTS AND METHODS: Two hundred and thirty-three patients aged 4-86 years were included in the descriptive study. Scores and sub-scores were analyzed by age and by disease subtypes. Sensitivity to change (responsiveness) was estimated in patients having had at least two evaluations with at least six months between the first and the second. RESULTS: Motor function measure scores decrease with age, especially sub-scores D1 and D3. There were no significant differences between the scores according to type of Charcot-Marie-Tooth disease. The scores were significantly higher for ambulatory than for non-ambulatory patients. Significant responsiveness was demonstrated only in type 2 Charcot-Marie-Tooth disease. DISCUSSION/CONCLUSIONS: Our results suggest that, especially for D1 and D3 sub-scores, the motor function measure is a reliable and valid outcome measure that can be usefully applied in longitudinal follow-up. Studies of longer duration could demonstrate its responsiveness in other Charcot-Marie-Tooth disease subtypes.

Clinical signs and radiographic evidence of esophageal perforation after tetraplegia.

A diagnosis of esophageal perforation at some time after cervical spine surgery is difficult to establish since there exists no clinical picture specific to tetraplegic patients. We carried out a detailed retrospective study of revelatory clinical manifestations and conventional radiographic data in a series of 16 patients hospitalized at Hôpital Henry-Gabrielle (Lyon, France) for rehabilitation purposes between 1983 and 2010 and who presented this complication. The most frequent clinical picture associates cervical pain, fever and dysphagia. Simple front and side X-rays of the cervical spine led in 77% of the cases to a diagnosis of esophageal perforation. The most prevalent radiographic signs of the latter consist in osteosynthesis hardware or instrumentation failure, prevertebral free air next to the cervical esophagus and enlarged prevertebral space. Visualized esophageal X-rays, also known as series, highlight parenchymal opacity next to the posterior wall of the esophagus. A diagnosis of esophageal perforation needs to be carried out in order to facilitate suitable treatment and avoid the compromising of vital functions.

Facial macrosomatognosia and pain in a case of Wallenberg's syndrome: selective effects of vestibular and transcutaneous stimulations.

Macro- and micro-somatognosia refer to rare disorders of the cerebral representation of the body whereby patients perceive body parts as disproportionately large or small. Here we report the experimental study of a patient who, following a left lateral medullary stroke (Wallenberg's syndrome, including vestibular deficits) complained of a persistent somatosensory illusory sensation of swelling, confined to the left side of his face (i.e., left macrosomatognosia). This hemifacial somatosensory distortion was associated with a left facial anesthesia, and a neuropathic pain affecting the three branches of the left trigeminal nerve. In this study, we first document quantitatively the patient's somatosensory illusion by using a somatosensory-to-visual matching task in which the patient modified the picture of his own face to fit his left-sided somatosensory misperception. The patient's performance revealed that macrosomatognosia was confined to the second branch of the left trigeminal nerve. Perception of the size of visual objects was comparatively preserved. Second, we investigated the effects of two peripheral stimulations, which may affect the spatial component of somatosensory deficits (caloric vestibular stimulation, CVS; transcutaneous electrical nervous stimulation, TENS) and pain (TENS). Left CVS abolished the facial somatosensory illusion, for about 30min, but had no effect on the left facial pain. Conversely, left TENS substantially reduced the neuropathic pain during stimulation, but had no effect on macrosomatognosia, indicating a double dissociation between the two disorders. These results reveal that facial macrosomatognosia may be regarded as a high-order deficit of somatosensory perception of the shape and volume of the face, which fits the definition of 'hyperschematia' (i.e., when the body takes up too much room) originally proposed by Bonnier (1905). Our data also indicate that CVS may favor the restoration of the conscious representation of the shape and size of the face. Overall, these findings lend support to the view that afferent inputs from the vestibular system can affect in a specific fashion the activity of cerebral structures involved in the building up and updating of the topological description of body parts.

Acquired visual field defects rehabilitation: critical review and perspectives.

Visual field deficit (VFD) is one of the most commonly observed symptoms following brain injury. Persistent VFD and defective exploratory oculomotor scanning patterns often cause severe impairment in daily activities, particularly as regards visual exploration and reading. Homonymous hemianopia is consequently a powerful negative predictor of patient outcome. In spite of these quantitative and qualitative factors, there currently exists no consensus on rehabilitative therapy and treatment. Different approaches have nevertheless been developed, all of them having one therapeutic principle in common; repeated practice of a specific visual task, with the hope/expectation that improved performance will extend to a wide range of ecologically useful visual functions. The four main available methods aim at replacing part of the intact visual field with part of the damaged visual field (optical therapy using prisms), at partially restoring the lost visual field region (restorative therapies), at stimulating detection capacities in the blind field (stimulation or blindsight) or at substituting for the lost region by reorganizing the control of visual information processing and eye movements (compensatory therapies). This review explores the key data relative to these different approaches in terms of behavioral or imagery results. It also aims at critically analyzing the advantages and limits of each one. The importance of strict assessment in terms of deficiencies or disabilities is underlined. Finally, upon consideration of these data taken as a whole, it is suggested that efficient treatment would probably have to associate general components and more specific elements, according to what may be done with regard to other aspects of cognitive rehabilitation.

Oral anticoagulant treatment - evaluating the knowledge of patients admitted in physical medicine and rehabilitation units.

INTRODUCTION: While numerous therapeutic education programs exist in physical medicine and rehabilitation (PM&R), they rarely concern pharmacological treatments. Nevertheless, drugs prescribed during a hospital stay can have a significant risk of adverse events. Vitamin K antagonists (VKA) are among them. OBJECTIVE OF THE STUDY: To assess patients' knowledge on their oral anticoagulant treatment before their hospital discharge. METHODS: Fifty patients were enrolled in this prospective, monocenter study. Their level of knowledge was assessed by a semi-structured interview between the pharmacist and the patients and/or their caregivers. RESULTS: Seventy percent of patients were able to give the name of the drug they were taking, 82% could explain its effect and finally, 24% of patient knew their INR target values. Twenty-two percent of patients were able to describe the symptoms in case of overdose and what to do in that case. Forty percent of patients were aware of food interactions and 60% of self-medication risks. The patient's knowledge and behavior acquired during their hospital stay are not enough to guarantee a safe treatment management upon discharge. Based on this study, therapeutic patient education sessions were implemented. CONCLUSION: These results suggest that specific drug therapy management sessions should be developed as part of PM&R's therapeutic education programs for patients.

Representation and disconnection in imaginal neglect.

Patients with neglect failure to detect, orient, or respond to stimuli from a spatially confined region, usually on their left side. Often, the presence of perceptual input increases left omissions, while sensory deprivation decreases them, possibly by removing attention-catching right-sided stimuli (Bartolomeo, 2007). However, such an influence of visual deprivation on representational neglect was not observed in patients while they were imagining a map of France (Rode et al., 2007). Therefore, these patients with imaginal neglect either failed to generate the left side of mental images (Bisiach & Luzzatti, 1978), or suffered from a co-occurrence of deficits in automatic (bottom-up) and voluntary (top-down) orienting of attention. However, in Rode et al.'s experiment visual input was not directly relevant to the task; moreover, distraction from visual input might primarily manifest itself when representation guides somatomotor actions, beyond those involved in the generation and mental exploration of an internal map (Thomas, 1999). To explore these possibilities, we asked a patient with right hemisphere damage, R.D., to explore visual and imagined versions of a map of France in three conditions: (1) 'imagine the map in your mind' (imaginal); (2) 'describe a real map' (visual); and (3) 'list the names of French towns' (propositional). For the imaginal and visual conditions, verbal and manual pointing responses were collected; the task was also given before and after mental rotation of the map by 180 degrees . R.D. mentioned more towns on the right side of the map in the imaginal and visual conditions, but showed no representational deficit in the propositional condition. The rightward inner exploration bias in the imaginal and visual conditions was similar in magnitude and was not influenced by mental rotation or response type (verbal responses or manual pointing to locations on a map), thus suggesting that the representational deficit was robust and independent of perceptual input in R.D. Structural and diffusion MRI demonstrated damage to several white matter tracts in the right hemisphere and to the splenium of corpus callosum. A second right-brain damaged patient (P.P.), who showed signs of visual but not imaginal neglect, had damage to the same intra-hemispheric tracts, but the callosal connections were spared. Imaginal neglect in R.D. may result from fronto-parietal dysfunction impairing orientation towards left-sided items and posterior callosal disconnection preventing the symmetrical processing of spatial information from long-term memory.

Functional anatomy of the therapeutic effects of prism adaptation on left neglect.

OBJECTIVE: To investigate the anatomic substrates underlying the beneficial effect of prism adaptation in five patients with persistent left neglect following right stroke. METHODS: In a functional imaging PET study, we used a covariation analysis to examine linear changes of regional cerebral blood flow over sessions as a function of left neglect improvement. RESULTS: The network of significant brain regions associated with improvement of left neglect performance produced by prism adaptation involved the right cerebellum, the left thalamus, the left temporo-occipital cortex, the left medial temporal cortex, and the right posterior parietal cortex. CONCLUSION: Our results suggest that the realignment of visuomotor coordinates is processed by the cerebellum and that low level sensorimotor adaptation actively modulates cerebral areas, albeit now relying on intact cerebellocerebral connections. Hence, our data support the hypothesis that the beneficial effect of prism adaptation on the clinical presentation of left neglect derives from modulation of cortical regions implicated in spatial cognition.

Does action make the link between number and space representation? Visuo-manual adaptation improves number bisection in unilateral neglect.

If the visual world is artificially shifted by only 10 degrees, people initially experience difficulty in directing their actions toward visual goals, but then rapidly compensate the visual distortion. The consequence of such adaptation can be measured as visual and proprioceptive aftereffects, as well as by performance on pointing tasks without visual feedback. Recent work has shown that more cognitive deficits can be improved following prism adaptation in patients with unilateral neglect. Here we show that a short visuo-manual adaptation to prisms improves performance on a mental number-bisection task recently shown to be impaired in unilateral neglect. The association previously found between space and number representation (the mental number line) may thus be grounded in common action principles. Our results suggest that visuo-motor plasticity functionally links parietal areas involved in space and number representation.