Deep brain stimulation of the subthalamic nucleus restores spatial reversal learning in patients with Parkinson's disease.

Spatial learning and navigation are supported by distinct memory systems in the human brain such as the hippocampus-based navigational system and the striatum-cortex-based system involved in motor sequence, habit and reversal learning. Here, we studied the role of subthalamic circuits in hippocampus-associated spatial memory and striatal-associated spatial reversal learning formation in patients with Parkinson's disease, who underwent a deep brain stimulation of the subthalamic nucleus. Deep brain stimulation patients (Parkinson's disease-subthalamic nucleus: n = 26) and healthy subjects (n = 15) were tested in a novel experimental spatial memory task based on the Morris water maze that assesses both hippocampal place memory as well as spatial reversal learning. All subjects were trained to navigate to a distinct spatial location hidden within the virtual environment during 16 learning trials in a subthalamic nucleus Stim-On condition. Patients were then randomized into two groups with either a deep brain stimulation On or Off condition. Four hours later, subjects were retested in a delayed recall and reversal learning condition. The reversal learning was realized with a new hidden location that should be memorized during six consecutive trials. The performance was measured by means of an index indicating the improvement during the reversal learning. In the delayed recall condition, neither patients, healthy subjects nor the deep brain stimulation On- versus Off groups showed a difference in place memory performance of the former trained location. In the reversal learning condition, healthy subjects (reversal index 2.0) and patients in the deep brain stimulation On condition (reversal index 1.6) showed a significant improvement. However, patients in the deep brain stimulation Off condition (reversal index 1.1) performed significantly worse and did not improve. There were no differences between all groups in a final visual guided navigation task with a visible target. These results suggest that deep brain stimulation of subthalamic nucleus restores spatial reversal learning in a virtual navigation task in patients with Parkinson's disease and gives insight into the neuromodulation effects on cognition of subthalamic circuits in Parkinson's disease.

Pilot Study of an Attention and Executive Function Cognitive Intervention in Children with Autism Spectrum Disorders.

This pilot study investigated the efficacy of a game-based cognitive training program (Caribbean Quest; CQ) for improving attention and executive function (EF) in school-aged children with Autism Spectrum Disorder (ASD). CQ is a 'serious game' that uses a hybrid process-specific/compensatory approach to remediate attention and EF abilities through repetitive, hierarchically graded exercises delivered in an adaptive format. Game-play is accompanied by instruction in metacognitive strategies delivered by an adult trainer. Twenty children diagnosed with ASD (ages 6-12 years) completed 12 h of intervention in schools over 8-10 weeks that was facilitated by a trained Research Assistant. Pre-post testing indicated near transfer gains for visual working memory and selective attention and far transfer effects for math fluency. Exit interviews with parents and school staff indicated anecdotal gains in attention, EF, emotion-regulation, flexibility, communication, and social skills. Overall, this study provides preliminary support for the feasibility and potential efficacy of the CQ when delivered in schools to children with ASD.

Impact of radiotherapy on implant-based prosthetic rehabilitation in patients with head and neck cancer: A prospective observational study on implant survival and quality of life-Preliminary results.

PURPOSE: To study implant-based prosthetic rehabilitation of head and neck cancer patients with focus on implant survival and quality of life. MATERIALS AND METHODS: The prospective observational study presents preliminary results of 29 edentulous head neck cancer patients (20 patients after radiotherapy) with 165 OsseoSpeed implants. Implant success after 1-year follow-up was evaluated by means of the Albrektsson criteria. Quality of life was analysed with the EORTC QLQ-C30, QLQ-H&N35, and OHIP 14 questionnaires. RESULTS: The overall implant survival rate after 1 year was 95.2% (157/165). Implant success measured by the Albrektsson criteria showed a lower success rate of 86.7% (143/165), mainly because of peri-implant marginal bone loss with a mean of 0.8 mm after 1 year. Xerostomia (p = 0.008), implant insertion within the radiation target volume (p = 0.09), implantation in transplanted bone (p = 0.05), and smoking (p = 0.041) were the main reasons for implant failure, followed by D4 bone quality, maxillary implant site, and insufficient primary stability. Speaking, swallowing, eating, as well as social integration and individual self-confidence had considerably improved 1 year after denture placement compared to before treatment. CONCLUSION: Implant-based prosthetic rehabilitation of head and neck cancer patients is possible at a calculable risk and significantly improves patients' quality of life.