Successful rehabilitation with respect to the activities of daily living (ADL) requires accurate and effective assessment and training. A number of studies have emphasized the requirement for rehabilitation methods that are both relevant to the patient's real world environment, and that can also be transferred to other daily living tasks. Virtual reality (VR) has many advantages over other ADL rehabilitation techniques, and offers the potential to develop a human performance testing and training environment. Therefore, in this study, the virtual supermarket was developed and the possibility of using a VR system to assess and train cognitive ability in ADL investigated. This study demonstrates that VR technology offers great promise in the field of ADL training.

ObjectiveTo investigate the analgesic effect of transcranial direct current stimulation (tDCS) over the primary motor (M1), dorsolateral prefrontal cortex (DLPFC), and sham tDCS in patients with painful diabetic polyneuropathy (PDPN).MethodsPatients with PDPN (n=60) were divided randomly into the three groups (n=20 per group). Each group received anodal tDCS with the anode centered over the left M1, DLPFC, or sham stimulation for 20 minutes at intensity of 2 mA for 5 consecutive days. A blinded physician rated the patients' pain using a visual analog scale (VAS), Clinical Global Impression (CGI) score, anxiety score, sleep quality, Beck Depression Inventory (BDI), and the pain threshold (PT) to pressure.ResultsAfter the tDCS sessions, the M1 group showed a significantly greater reduction in VAS for pain and PT versus the sham and DLPFC groups (p<0.001). The reduction in VAS for pain was sustained after 2 and 4 weeks of follow-up in the M1 group compared with the sham group (p<0.001, p=0.007). Significant differences were observed among the three groups over time in VAS for pain (p<0.001), CGI score (p=0.01), and PT (p<0.001). No significant difference was observed among the groups in sleep quality, anxiety score, or BDI score immediately after tDCS.ConclusionFive daily sessions of tDCS over the M1 can produce immediate pain relief, and relief 2- and 4-week in duration in patients with PDPN. Our findings provide the first evidence of a beneficial effect of tDCS on PDPN.

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BackgroundSeveral experimental studies in stroke patients suggest that mirror therapy and various virtual reality programs facilitate motor rehabilitation. However, the underlying mechanisms for these therapeutic effects have not been previously described.ObjectivesWe attempted to delineate the changes in corticospinal excitability when individuals were asked to exercise their upper extremity using a real mirror and virtual mirror. Moreover, we attempted to delineate the role of visual modulation within the virtual environment that affected corticospinal excitability in healthy subjects and stroke patients.MethodsA total of 18 healthy subjects and 18 hemiplegic patients were enrolled into the study. Motor evoked potential (MEP)s from transcranial magnetic stimulation were recorded in the flexor carpi radialis of the non-dominant or affected upper extremity using three different conditions: (A) relaxation; (B) real mirror; and (C) virtual mirror. Moreover, we compared the MEPs from the virtual mirror paradigm using continuous visual feedback or intermittent visual feedback.ResultsThe rates of amplitude increment and latency decrement of MEPs in both groups were higher during the virtual mirror task than during the real mirror. In healthy subjects and stroke patients, the virtual mirror task with intermittent visual feedback significantly facilitated corticospinal excitability of MEPs compared with continuous visual feedback.ConclusionCorticospinal excitability was facilitated to a greater extent in the virtual mirror paradigm than in the real mirror and in intermittent visual feedback than in the continuous visual feedback, in both groups. This provides neurophysiological evidence supporting the application of the virtual mirror paradigm using various visual modulation technologies to upper extremity rehabilitation in stroke patients.

Stroke and traumatic brain injury affect an increasing number of people, many of whom retain permanent damage in cognitive functions. Conventionally, cognitive function has been assessed by a paper-based neuropsychological evaluation. However these test environments differ substantially from everyday life. This problem can be overcome by using virtual reality (VR) to objectively evaluate behaviors and cognitive function in simulated daily activities. With our virtual shopping simulation, we compared people who had undergone a stroke with control participants in an immersive VR program that used a head-mounted display (HMD). We evaluated user satisfaction with the tests, complications, and the user interface. Significant differences were consistently found between the stroke group and the control group for the following tasks: stage 1 performance index, interaction error; stage 2 delayed recognition memory score, attention index; and stage 3 executive index (p < 0.001). Perceptive dysfunction, visuospatial dysfunction, level of computer experience, and level of education affected the performance of the stroke group. The frequency of complications in the stroke group, calculated using the cut-off score for the Simulator Sickness Questionnaire, was 9.6% for nausea, 41.9% for oculomotor complications, and 25.8% for disorientation. The frequency of complications between the stroke and control groups was not significantly different. Thirty-five percent of participants in the stroke group and 13% in the control group reported difficulties with using the joystick. This computer-generated VR-based cognitive test shows promise in assessing cognitive function in patients with stroke. More refinements are needed in the user interface and the projection methods.

Objective: Action observation (AO) combined with brain computer interface (BCI) technology enhances the cortical activation. Peripheral electrical stimulation (PES) is known to increase the corticospinal excitability, thereby activating brain plasticity. To maximize motor recovery, we assessed the effects of BCI-AO combined with PES on corticospinal plasticity. Approach: Seventeen patients with chronic hemiplegic stroke and 17 healthy subjects were recruited. The participants watched a video of repetitive grasping actions with four different tasks for 15 mins: A) AO alone; B) AO + PES; C) BCI-AO + continuous PES; D) BCI-AO + triggered PES. PES was applied at the ulnar nerve of the wrist. The tasks were performed in a random order at least 3 days apart. We assessed the latency and amplitude of the motor evoked potentials (MEPs). We examined changes in MEP parameters pre-and post-exercise across the four tasks in the FDI muscle of the dominant hand (healthy subjects) and affected hand (stroke patients). Main results: The decrease in MEP latency and increase in MEP amplitude after the four tasks were significant in both groups. The increase in MEP amplitude was sustained for 20 mins after tasks B, C, and D in both groups. The increase in MEP amplitude was significant between tasks A vs B, B vs C, and C vs D. The estimated mean difference in MEP amplitude post-exercise was highest for A and D in both groups. Significance: The results indicate that BCI-AO combined with PES is superior to AO alone or AO + PES for facilitating corticospinal plasticity in both healthy subjects and stroke patients. Furthermore, this study supports the idea that synchronized activation of cortical and peripheral networks can enhance neuroplasticity after stroke. We suggest that the BCI-AO paradigm and PES could provide a novel neurorehabilitation strategy for stroke patients.

Diabetic peripheral neuropathy (DPN) is a common complication of type 2 diabetes mellitus (DM). DPN causes a decrease in proprioception, which could reduce balance ability. We investigated the association of impaired vibration sense, based on vibration perception threshold (VPT), with assessments of balance and other factors affecting balance impairment and fear of falling in patients with type 2 DM. Sixty-three patients with DM aged >50 years were categorized as having normal vibration sense (NVS; n = 34) or impaired vibration sense (IVS; n = 29) according to a VPT value of 8.9 μm. The following parameters were evaluated for all patients: postural steadiness through the fall index using posturography, functional balance through the Berg Balance Scale (BBS), the Timed Up and Go test (TUG), and fear of falling through the Falls Efficacy Scale-International (FES-I). The IVS group showed a significantly greater balance impairment in fall index, BBS, and TUG, as well as greater fear of falling on the FES-I than the NVS group. The linear regression analysis showed that the fall index was associated only with the VPT, whereas BBS, TUG, and FES-I were associated with the VPT, age, and/or lower extremity muscle strength. VPT, age, and/or muscle strength were identified as predictors of balance and fear of falling in patients with type 2 DM. Therefore, along with age and lower extremity strength, the VPT can be useful for balance assessment in patients with type 2 DM.

We investigated a virtual reality (VR) proprioceptive rehabilitation system that could manipulate the visual feedback of upper-limb during training and could do training by relying on proprioception feedback only. Virtual environments were designed in order to switch visual feedback on/off during upper-limb training. Two types of VR training tasks were designed for evaluating the effect of the proprioception focused training compared to the training with visual feedback. In order to evaluate the developed proprioception feedback virtual environment system, we recruited ten stroke patients (age: 54.7± 7.83years, on set: 3.29± 3.83 years). All patients performed three times PFVE task in order to check the improvement of proprioception function just before training session, after one week training, and after all training. In a comparison between FMS score and PFVE, the FMS score had a significant relationship with the error distance(r = -.662, n=10, p = .037) and total movement distance(r = -.726, n=10, p = .018) in PFVE. Comparing the training effect between in virtual environment with visual feedback and with proprioception, the click count, error distance and total error distance was more reduced in PFVE than VFVE. (Click count: p = 0.005, error distance: p = 0.001, total error distance: p = 0.007). It suggested that the proprioception feedback rather than visual feedback could be effective means to enhancing motor control during rehabilitation training. The developed VR system for rehabilitation has been verified in that stroke patients improved motor control after VR proprioception feedback training.