P293: Effects of transcranial direct current stimulation on dual-task gait performance in patients with Parkinson’s disease

Abstract

s of Poster Presentations / Clinical Neurophysiology 125, Supplement 1 (2014) S1–S339 S127 HC/PD groups while no significant difference was observed between HC and PD. Conclusions: Our results show increased engagement of the dorsal attention network in the PDD group as compared to both PD and HC when switching from baseline to the simple visual processing task condition. This result may reflect increased top-down control in the PDD group. Acknowledgement: The study was supported by the grant of the Czech Ministry of Health NT13499. P292 Features of patellar pendulum triggered by patella T reflex in rigidity H. Uysal1, M. Guerbuez1, F. Kizilay1, Y. Albayrak2, S. Bilgin2 1Akdeniz University, Clinical Neurophysiology, Antalya, Turkey; 2Akdeniz University, Faculty of Engineering, Antalya, Turkey Parkinson’s disease is a movement disorder characterized by an increase in muscle tone. Rigidity affects motor capacity and daily functions of the patients. Aim of the study is analyzing electrophysiologically and kinesiologically features of the patellar pendulum that was triggered by patella T reflex in the Parkinson patients with rigidity. Method: We stimulated patella T reflex by an electronic triggered reflex hammer and recorded muscle action potenteials by surface electrodes from quadriceps femoris and biceps femoris muscles. We analyzed electrophysiological features of patellar T reflex and also analyzed characteristics of the patellar pendulum during the reflex motion in patients with rigidity and normal subjects. Joint angle changes and instantaneous angular velocity during reflex was measured with a goniometric approach. Results: Twenty five normal subjects included study as a control group. Patella T reflex had 17.9±1.9 milliseconds latency and 6404.1±2860.0 microvolt amplitude. Initial time of joint motion was 51.5±9.9 milliseconds and it was measured with an accelerometer. The pendulum count was 4.8±1.5. Angle of joint motion was 18.3±5.6°; extension time was 317.4±23.4 milliseconds; instantaneous angular velocity was 58.0±16.6 degrees/second; frequency was 1.0±0.1. Damping ratio of the pendulum was calculated as 0.6±0.2. A parameter was developed using by significant kinesiological findings and it was 60.3±16.1 degrees/second*Hz. There were 45 Parkinson’s disease patients in the rigidity group. Patella T Figure 1. Pendulum triggered by patellar T reflex – normal case. Figure 2. UPDRS grade 1 rigidity. reflex had 17.9±2.4 milliseconds latency and 4467.7±2528.4 microvolt amplitude. Bf-LLR response had 94.2±17.0 milliseconds latency, 770.8±488.0 microvolt amplitude and it was seen in 28 cases. Initial time of joint motion was 61.7±5.7 milliseconds. The pendulum count was 1.8±0.7. Angle of joint motion was 9.2±4.2°; extension time was 274.5±39.3 milliseconds; instantaneous angular velocity was 33.7±15.5 degrees/second; frequency was 1.3±0.2. Damping ratio was calculated as 0.2±0.2. The parameter value was calculated as 27.5±13.9 degrees/second*Hz. Conclusion: Kinesiologic features of patellar T reflex change significantly in Parkinson’s disease. The most striking changes occur on the pendulum count and angle of the first movement. The parameter that generated by using kinesiologic scales can distinguish between Parkinson’s disease and normal subjects. P293 Effects of transcranial direct current stimulation on dual-task gait performance in patients with Parkinson’s disease