Rehabilitation of hemineglect of the left arm using movement detection bracelets activating a visual and acoustic alarm.

BACKGROUND: Hemineglect is frequent after right hemisphere stroke and prevents functional independence, but effective rehabilitation interventions are lacking. Our objective was to determine if a visual-acoustic alarm in the hemineglect arm activated by a certain discrepancy in movement of both hands can enhance neglect arm use in five tasks of daily living. METHODS: In this pre-post intervention study 9 stroke patients with residual hemineglect of the arm were trained for 7 days in five bimanual tasks of daily living: carrying a tray, button fastening, cutting food with knife and fork, washing the face with both hands and arm sway while walking. This was done through motion sensors mounted in bracelets on both wrists that compared movement between them. When the neglect-hand movement was less than a limit established by two fuzzy logic based classifiers, a visual-acoustic alarm in the neglect-hand bracelet was activated to encourage its use in the task. RESULTS: Both motion and function of the neglect hand improved during the seven days of training when visual-acoustic alarms were active but a worsening to baseline values occurred on day 8 and day 30 when alarms where switched off. Improvement was limited to vision-dependent tasks. CONCLUSIONS: Neglect-hand improvement with this approach is limited to bimanual activities in which an object is manipulated under vision control, but no short or long term learning happens.

Perceptual post-effects of left neck muscle vibration with visuo-haptic feedback in healthy individuals: A potential approach for treating spatial neglect.

Among the techniques used to reduce spatial neglect's symptoms, left neck muscle vibration (NMV) is alluring because it does not require the patient's attentional co-operation. The aim of this study was to determine the type of NMV-associated feedback that induced the most intense and longest-lasting egocentric post-effects. Eighty-seven healthy individuals were randomly assigned to four intervention groups: "neck muscle vibration, blindfolded" (NMV), "neck muscle vibration with vision" (NMV + V), "neck muscle vibration and visual finger-pointing" (NMV + P), and "visual finger-pointing" (P). An eyes-closed finger-pointing subjective straight-ahead (SSA) test was carried out before the intervention, immediately afterwards, and 30 min afterwards. The results showed that only the NMV + P intervention induced a lasting leftward bias of SSA. In addition, the deviation reported in this intervention group differed significantly from those observed in the other interventions. The combination of visuo-haptic feedback and neck-somatosensory stimulation may enable a full, lasting intermodal recalibration, which could be potentiated by the attention level engaged during voluntary pointing. These outcomes highlighted that the NMV technique could easily integrate into routine occupational therapy sessions for treating various aspects of neglect disorders.

Mental time travel and functional daily life activities in neglect patients: Recovery effects of rehabilitation by prism adaptation.

Recent neuropsychological evidence put forward impaired ability in processing particular aspects of time, such as Mental Time Travel (MTT), in brain damaged patients exhibiting a deficit of spatial attention (i.e., neglect) and the possibility to recover this MTT deficit through a manipulation of spatial attention by prism adaptation (PA). The aim of the present study was twofold. First, we explored whether the neglect patients' impairment in MTT is linked with an impairment in functional competences, such as processing temporal duration of everyday activities, motor abilities and independence in daily living. Second, we focused on rehabilitation, investigating the long-term duration of the benefits induced by a PA treatment on both mental time travel and the above-mentioned functional abilities. To these aims, neglect patients were submitted to a MTT task, as well as to a battery of tests assessing spatial attention, estimation of time duration, motor competence and independence in activities of daily living. All tests were performed before, at the end, and one week after 10 daily sessions of PA treatment inducing a leftward shift of spatial attention. Results suggest that neglect patients' impairment in MTT ability correlates with spatial attention deficit and with difficulties in producing reasonable temporal estimation of daily life activities. Crucially, the PA treatment induces a long-lasting and stable amelioration of MTT, spatial attention and functional competences.

Induced sensorimotor cortex plasticity remediates chronic treatment-resistant visual neglect.

Right brain injury causes visual neglect - lost awareness of left space. During prism adaptation therapy, patients adapt to a rightward optical shift by recalibrating right arm movements leftward. This can improve left neglect, but the benefit of a single session is transient (~1 day). Here we show that tonic disinhibition of left motor cortex during prism adaptation enhances consolidation, stabilizing both sensorimotor and cognitive prism after-effects. In three longitudinal patient case series, just 20 min of combined stimulation/adaptation caused persistent cognitive after-effects (neglect improvement) that lasted throughout follow-up (18-46 days). Moreover, adaptation without stimulation was ineffective. Thus stimulation reversed treatment resistance in chronic visual neglect. These findings challenge consensus that because the left hemisphere in neglect is pathologically over-excited it ought to be suppressed. Excitation of left sensorimotor circuits, during an adaptive cognitive state, can unmask latent plastic potential that durably improves resistant visual attention deficits after brain injury.

Transcutaneous electrical nerve stimulation effects on neglect: a visual-evoked potential study.

We studied the effects of transcutaneous electrical nerve stimulation (TENS) in six right-brain-damaged patients with left unilateral spatial neglect (USN), using both standard clinical tests (reading, line, and letter cancelation, and line bisection), and electrophysiological measures (steady-state visual-evoked potentials, SSVEP). TENS was applied on left neck muscles for 15', and measures were recorded before, immediately after, and 60' after stimulation. Behavioral results showed that the stimulation temporarily improved the deficit in all patients. In cancelation tasks, omissions and performance asymmetries between the two hand-sides were reduced, as well as the rightward deviation in line bisection. Before TENS, SSVEP average latency to stimuli displayed in the left visual half-field [LVF (160 ms)] was remarkably longer than to stimuli shown in the right visual half-field [RVF (120 ms)]. Immediately after TENS, latency to LVF stimuli was 130 ms; 1 h after stimulation the effect of TENS faded, with latency returning to baseline. TENS similarly affected also the latency SSVEP of 12 healthy participants, and their line bisection performance, with effects smaller in size. The present study, first, replicates evidence concerning the positive behavioral effects of TENS on the manifestations of left USN in right-brain-damaged patients; second, it shows putatively related electrophysiological effects on the SSVEP latency. These behavioral and novel electrophysiological results are discussed in terms of specific directional effects of left somatosensory stimulation on egocentric coordinates, which in USN patients are displaced toward the side of the cerebral lesion. Showing that visual-evoked potentials latency is modulated by proprioceptive stimulation, we provide electrophysiological evidence to the effect that TENS may improve some manifestations of USN, with implications for its rehabilitation.

Rehabilitation for Unilateral Neglect Following Stroke (review) / 中国康复理论与实践

@#Unilateral neglect is a common and advanced nervous disorder of stroke, well-recognized predictor of poor neural functional outcome following stroke. There are several rehabilitation Methods including sensation input, visual scanning training, vestibular stimulation, head and trunk rotation, suggestive therapy, environmental adaptation and activities of daily living training, and some new therapies including prism adaptation, constraint-induced movement therapy, eye patching and transcranial magnetic stimulation developed in the past few years, which to some extent are effective on the treatment of neglect.

Rehabilitation of Unilateral Spatial Neglect(review) / 中国康复理论与实践

@#Unilateral spatial neglect is recognized as a significant disabling deficit, clinically defined as a failure to report, respond or orient to novel stimuli presented on the side opposite to a brain lesion. It is a predictor of poor functional outcome following right hemisphere lesion. Many different rehabilitation techniques or treatments have been put forward to alleviate, reduce or remediate spatial neglect. In the following review, we described, explained these Methods in terms of their underlying or motivatng mechanisms and evaluated in terms of the current evidence base for their effectiveness for clinical rehabilitation.