Virtual Social Interaction in a Multiplayer-Online Video Game Increases Implicit Learning: An EEG Study.

It is well known that social interaction enhances learning processes, improving abilities such as attention and memorization. However, it is not clear whether similar advantages may be obtained even in virtual environments. Here, we investigate whether virtual interactions in a video game, similarly to real-life social interactions, may improve individuals' performance in a subsequent implicit learning task. Twenty-one healthy participants were asked to play a cooperative video game for 20 minutes in three different gaming modalities: alone (Single-Player); together with someone without verbal interactions (Multi-Player -); and with someone with verbal interactions (Multi-Player +). After each gaming session, participants were presented with an EEG paradigm directed to measure mismatch negativity (MMN) responses, a well-validated index of implicit learning. MMN responses were significantly larger following Multi-Player +, as compared with Single-Player, and Multi-Player - conditions. No significant difference was found between Single-Player, and Multi-Player - conditions. These results indicate that implicit learning processes are enhanced following communicative virtual interactions. Verbal interaction in a virtual environment seems necessary to elicit social copresence and its positive effects on learning performances. This finding may have important implications for the design of virtual rehabilitation protocols and distance learning programs.

Re-learning mental representation of walking after a brain lesion. Effects of a cognitive-motor training with a robotic orthosis.

Introduction: Stroke-related deficits often include motor impairments and gait dysfunction, leading to a limitation of social activities and consequently affecting the quality of life of stroke survivors. Neurorehabilitation takes advantage of the contribution of different techniques in order to achieve more benefits for patients. Robotic devices help to improve the outcomes of physical rehabilitation. Moreover, motor imagery seems to play a role in neurological rehabilitation since it leads to the activation of the same brain areas as actual movements. This study investigates the use of a combined physical and cognitive protocol for gait rehabilitation in stroke patients. Methods: Specifically, we tested the efficacy of a 5-week training program using a robotic orthosis (P.I.G.R.O.) in conjunction with motor imagery training. Twelve chronic stroke patients participated in the study. We evaluated balance and gait performance before and after the training. Six of them underwent fMRI examination before and after the training to assess the effects of the protocol on brain plasticity mechanisms in motor and imagery tasks. Results: Our results show that the rehabilitation protocol can effectively improve gait performance and balance and reduce the risk of falls in stroke patients. Furthermore, the fMRI results suggest that rehabilitation is associated with cerebral plastic changes in motor networks. Discussion: The present findings, if confirmed by future research, have the potential to advance the development of new, more effective rehabilitation approaches for stroke patients, improving their quality of life and reducing the burden of stroke-related disability.

Visual integration across fixation: automatic processes are split but conscious processes remain unified in the split-brain.

The classic view holds that when "split-brain" patients are presented with an object in the right visual field, they will correctly identify it verbally and with the right hand. However, when the object is presented in the left visual field, the patient verbally states that he saw nothing but nevertheless identifies it accurately with the left hand. This interaction suggests that perception, recognition and responding are separated in the two isolated hemispheres. However, there is now accumulating evidence that this interaction is not absolute; for instance, split-brain patients are able to detect and localise stimuli anywhere in the visual field verbally and with either hand. In this study we set out to explore this cross-hemifield interaction in more detail with the split-brain patient DDC and carried out two experiments. The aim of these experiments is to unveil the unity of deliberate and automatic processing in the context of visual integration across hemispheres. Experiment 1 suggests that automatic processing is split in this context. In contrast, when the patient is forced to adopt a conscious, deliberate, approach, processing seemed to be unified across visual fields (and thus across hemispheres). First, we looked at the confidence that DDC has in his responses. The experiment involved a simultaneous "same" versus "different" matching task with two shapes presented either within one hemifield or across fixation. The results showed that we replicated the observation that split brain patients cannot match across fixation, but more interesting, that DDC was very confident in the across-fixation condition while performing at chance-level. On the basis of this result, we hypothesised a two-route explanation. In healthy subjects, the visual information from the two hemifields is integrated in an automatic, unconscious fashion via the intact splenium, and this route has been severed in DDC. However, we know from previous experiments that some transfer of information remains possible. We proposed that this second route (perhaps less visual; more symbolic) may become apparent when he is forced to use a deliberate, consciously controlled approach. In an experiment where he is informed, by a second stimulus presented in one hemifield, what to do with the first stimulus that was presented in the same or the opposite hemifield, we showed that there was indeed interhemispheric transfer of information. We suggest that this two-route model may help in clarifying some of the controversial issues in split-brain research.

Mini Nutritional Assessment in patients with Parkinson's disease: correlation between worsening of the malnutrition and increasing number of disease-years.

OBJECTIVE: To monitor the nutritional status of patients with Parkinson's disease using the Mini Nutritional Assessment (MNA) questionnaire. PATIENTS AND METHODS: This was a 3-year longitudinal study conducted in a national referral centre for Parkinson's disease and other movement disorders. The cohort included 61 Parkinson's disease patients, 37 men and 24 women, mean age of 70.5 +/- 5.5 years, mean duration of disease 9 +/- 6.3 years; 35 patients were followed-up after 3 years. RESULTS: MNA score diminished from 24.9 +/- 1.6 to 24 +/- 2.5 (P = 0.02); the proportion of patients at risk of malnutrition increased from 22.9% to 34.3%. A linear correlation was observed between MNA score and the duration of disease (P = 0.0096). The dietary assessment subscore significantly diminished (8.6 versus 8.1; P = 0.0009) as did body mass index (25.9 +/- 3.5 kg/m(2) versus 27.1 +/- 3.1 kg/m(2); P = 0.001). CONCLUSIONS: The evaluation of nutritional status should be part of the routine work-up of a Parkinson's disease patient. Dietary education should be included amongst the therapeutic measures designed to improve the general conditions in Parkinson's disease.