The presence of semantic content in a visual recognition memory task reduces the severity of neglect.

Patients with right hemisphere damage often show a lateral bias when asked to report the left side of mental images held in visual working memory (i.e. representational neglect). The neural basis of representational neglect is not well understood. One hypothesis suggests that it reflects a deficit in attentional-exploratory mechanisms, i.e. an inability to direct attention to the left side of the image. Another proposition states that intact visual working memory (VWM) is necessary for correctly creating a mental image. Here we examined two components of VWM in patients with unilateral spatial neglect (USN): memory for identity, and memory for spatial position. We manipulated the strength of memory representations by presenting two distinct categories of objects, in separate blocks. These were familiar namable objects (fruits, etc.), and unfamiliar abstract objects. The former category elicits stronger working-memory traces, thanks to preexisting visual and semantic representations in long-term memory. We hypothesized that if USN patients show a lateralized deficit in VWM, it should be more pronounced for abstract objects, due to their weaker working-memory traces. Importantly, to isolate a spatially lateralized deficit in memory from a failure to fully perceive the object-arrays, we ensured that all included patients perceived every item during the encoding phase. We used a working-memory task: participants viewed object arrays and had to memorize items' identities and spatial positions. Then, single objects were presented requiring 'old/new' recognition, and retrieval of 'old' items' original positions. Our results show a lateral bias in patients' recognition-memory performance. Remarkably, it was threefold milder for namable objects compared to abstract objects. We conclude that VWM lateralized deficit is substantial in USN patients and could play a role in representational neglect.

Nature and nurture effects on the spatiality of the mental time line.

The nature-nurture debate regarding the origin of mental lines is fundamental for cognitive neuroscience. We examined natural-nurture effects on the mental time line, applying three different challenges to the directionality of time representation. We tested (1) patients with left-neglect and healthy participants, who are (2) left-to-right or right-to-left readers/writers, using (3) a lateralized left-right button press or a vocal mode in response to a mental time task, which asks participants to judge whether events have already happened in the past or are still to happen in the future. Using lateralized responses, a spatial-temporal association of response code (STEARC) effect was found, in concordance with the cultural effects. With vocal responses (no lateralization), past and future events showed similar results in both cultures. In patients with neglect, who have a deficit of spatial attention in processing the left side of space, future events were processed more slowly and less accurately than past events in both cultures. Our results indicate the existence of a "natural" disposition to map past and future events along a horizontal mental time line, which is affected by the different ways in which spatial representation of time is introduced.

Rehabilitation outcome of progressive multifocal leukoencephalopathy in HIV-positive patients: a report of two cases.

PURPOSE: To describe the rehabilitation treatment and outcome of progressive multifocal leukoencephalopathy (PML) in the context of Human Immunodeficiency Virus (HIV). METHOD: The medical history of two HIV-positive patients with PML was reviewed; information on their neurological impairments, rehabilitation treatment and outcome was gathered. RESULTS: The patients, a 47-year-old married man and a 34-year-old single man, both suffered from dense right hemiplegia and motor aphasia. Their rehabilitation course was delayed and prolonged: they were suitable for intensive multidisciplinary rehabilitation only 8 months or more after the initial presentation. Their treatment in outpatient rehabilitation daycare three times a week, that lasted 7 months on average, resulted in slow and steady functional improvement. At the end of the rehabilitation treatment, both patients were living at home, able to express themselves, and able to walk independently with an assistive device. They remained with moderate disability (modified Rankin scale of 3). CONCLUSION: PML patients require prolonged multidisciplinary rehabilitation treatment; however, considerable progress can be achieved. Implications for Rehabilitation Progressive multifocal leukoencephalopathy (PML) is a disabling disease occurring in particular in the context of Human Immunodeficiency Virus (HIV). Presently a growing number of HIV-positive PML patients eventually survive the disease and remain with severe neurological impairments. PML patients require prolonged multidisciplinary rehabilitation treatment, and considerable progress can be achieved.

Effectiveness of multi-disciplinary rehabilitation for patients with Neuromyelitis Optica.

INTRODUCTION: Neuromyelitis optica (NMO), previously considered a subtype of multiple sclerosis (MS), is now known to be a unique disorder associated with autoantibodies against aquaporin-4. The rehabilitation protocols for MS have been applied to NMO, without specific measures of efficacy. PURPOSE: The evaluation of the effectiveness of an MS type inpatient rehabilitation program for patients with NMO. PATIENT AND METHODS: Retrospective chart reviews of 15 inpatients with NMO and 32 inpatients with MS. Clinical severity was assessed by the Expanded Disability Status Scale (EDSS), functional assessments were scored using the Functional Independence Measure (FIM), the Montebello Rehabilitation Factor Score (MRFS), and the Functional Ambulation Category (FAC). There was a higher percentage of women in the NMO group (87% vs 56% P = 0.003). The MS group had significantly more cognitive and communication deficits (P = 0.003 and P = 0.00001). No significant differences were found in admission FIM, EDSS and FAC scores. RESULTS: Both groups benefitted, however at discharge, the NMO group showed greater improvement in FIM scores (NMO admission 79 ± 24, discharge 98 ± 21; MS admission 80 ± 28, discharge 89 ± 28); and lower EDSS score (NMO from 7.2 ± 1.4 to 6.3 ± 1.4; MS from 7.4 ± 1.4 to 7 ± 1.5). CONCLUSIONS: Inpatient multidisciplinary rehabilitation programs available for the patients with MS may be successfully implemented for patients with NMO.

Visual memory in unilateral spatial neglect: immediate recall versus delayed recognition.

Patients with unilateral spatial neglect (USN) often show impaired performance in spatial working memory tasks, apart from the difficulty retrieving "left-sided" spatial data from long-term memory, shown in the "piazza effect" by Bisiach and colleagues. This study's aim was to compare the effect of the spatial position of a visual object on immediate and delayed memory performance in USN patients. Specifically, immediate verbal recall performance, tested using a simultaneous presentation of four visual objects in four quadrants, was compared with memory in a later-provided recognition task, in which objects were individually shown at the screen center. Unlike healthy controls, USN patients showed a left-side disadvantage and a vertical bias in the immediate free recall task (69% vs. 42% recall for right- and left-sided objects, respectively). In the recognition task, the patients correctly recognized half of "old" items, and their correct rejection rate was 95.5%. Importantly, when the analysis focused on previously recalled items (in the immediate task), no statistically significant difference was found in the delayed recognition of objects according to their original quadrant of presentation. Furthermore, USN patients were able to recollect the correct original location of the recognized objects in 60% of the cases, well beyond chance level. This suggests that the memory trace formed in these cases was not only semantic but also contained a visuospatial tag. Finally, successful recognition of objects missed in recall trials points to formation of memory traces for neglected contralesional objects, which may become accessible to retrieval processes in explicit memory.

Novel virtual reality system integrating online self-face viewing and mirror visual feedback for stroke rehabilitation: rationale and feasibility.

PURPOSE: To introduce the rationale of a novel virtual reality system based on self-face viewing and mirror visual feedback, and to examine its feasibility as a rehabilitation tool for poststroke patients. METHOD: A novel motion capture virtual reality system integrating online self-face viewing and mirror visual feedback has been developed for stroke rehabilitation.The system allows the replacement of the impaired arm by a virtual arm. Upon making small movements of the paretic arm, patients view themselves virtually performing healthy full-range movements. A sample of 6 patients in the acute poststroke phase received the virtual reality treatment concomitantly with conservative rehabilitation treatment. Feasibility was assessed during 10 sessions for each participant. RESULTS: All participants succeeded in operating the system, demonstrating its feasibility in terms of adherence and improvement in task performance. Patients' performance within the virtual environment and a set of clinical-functional measures recorded before the virtual reality treatment, at 1 week, and after 3 months indicated neurological status and general functioning improvement. CONCLUSIONS: These preliminary results indicate that this newly developed virtual reality system is safe and feasible. Future randomized controlled studies are required to assess whether this system has beneficial effects in terms of enhancing upper limb function and quality of life in poststroke patients.

Robot-assisted gait training in multiple sclerosis patients: a randomized trial.

BACKGROUND: Preservation of locomotor activity in multiple sclerosis (MS) patients is of utmost importance. Robotic-assisted body weight-supported treadmill training is a promising method to improve gait functions in neurologically impaired patients, although its effectiveness in MS patients is still unknown. OBJECTIVE: To compare the effectiveness of robot-assisted gait training (RAGT) with that of conventional walking treatment (CWT) on gait and generalized functions in a group of stable MS patients. METHODS: A prospective randomized controlled trial of 12 sessions of RAGT or CWT in MS patients of EDSS score 5-7. Primary outcome measures were gait parameters and the secondary outcomes were functional and quality of life parameters. All tests were performed at baseline, 3 and 6 months post-treatment by a blinded rater. RESULTS: Fifteen and 17 patients were randomly allocated to RAGT and CWT, respectively. Both groups were comparable at baseline in all parameters. As compared with baseline, although some gait parameters improved significantly following the treatment at each time point there was no difference between the groups. Both FIM and EDSS scores improved significantly post-treatment with no difference between the groups. At 6 months, most gait and functional parameters had returned to baseline. CONCLUSIONS: Robot-assisted gait training is feasible and safe and may be an effective additional therapeutic option in MS patients with severe walking disabilities.

Fatigue, function, and mortality in older adults.

BACKGROUND: Although fatigue is common among the elderly people, little is known concerning its relationship with mortality and function over extended periods of time among the very old. This study evaluates the association of fatigue with health, functional status, and mortality from ages 70-88 years. METHODS: Mortality data from ages 70-88 years and both health and functional status at age 70, 78, and 85 years were assessed among a representative community-dwelling cohort born 1920-1921 from the Jerusalem Longitudinal Study (1990-2008). RESULTS: At age 70, 78, and 85, fatigue prevalence was 29%, 53%, and 68%, respectively, with increased prevalence among women. Fatigue was associated with poorer health, function, and psychosocial parameters at all ages and greater likelihood to deteriorate in subsequent self-rated health (SRH), functional status, loneliness, depression, and physical activity level. After adjustment, fatigue at age 70 predicted poor subsequent SRH, difficulty in activities of daily living, reduced levels of physical activity, and poor sleep satisfaction, and at age 78, fatigue predicted subsequent depression. Hazard ratios for mortality among fatigued participants were significant after adjustment for numerous risk factors. The addition of physical activity level and/or depression reduced the significance of the relationship between fatigue and mortality. CONCLUSIONS: Fatigue among the elderly people, up to and including the oldest old, has a significant negative impact on health status, function, and mortality. Pathways of action may be related to the complex relationship of fatigue with depression and levels of physical activity.

Spinal decompression sickness presenting as partial Brown-Sequard syndrome and treated with robotic-assisted body-weight support treadmill training.

OBJECTIVE: To describe the rehabilitation outcome of a case of spinal decompression sickness presenting as partial Brown-Sequard syndrome treated with robotic-assisted body-weight support treadmill training. STUDY DESIGN: Case report. BACKGROUND: Type II decompression sickness patients commonly suffer from myelopathy with gait disturbances necessitating rehabilitation. Robotic-assisted body-weight support treadmill training has been shown to improve the rehabilitation outcome of incomplete spinal cord injury. Its usefulness has not been described in decompression sickness myelopathy. METHODS: Robotic-assisted body-weight support treadmill training was administrated using the Lokomat. Primary outcomes were American Spinal Cord Association scale, Spinal Cord Independence Measurement, Berg Balance Test, and Walking Index for Spinal Cord Injury. RESULTS: The patient was admitted 3 weeks after the diving injury, with severe paraparesis and a T11 sensory neurological level, resembling partial Brown-Sequard syndrome. After 3 months of rehabilitation including 18 Lokomat sessions, American Spinal Cord Association score improved from C to D, Spinal Cord Independence Measurement improved from 50 to 90 out of 100. Berg Balance Test improved from 35 to 43 out of 56 and Walking Index for Spinal Cord Injury improved from 1 to 15 out of 20. Upon discharge he could walk with one crutch for more than 1 km. CONCLUSION: Robotic-assisted body-weight support treadmill training for spinal decompression sickness rehabilitation might be beneficial.