Effects of Transcutaneous Electrical Nerve Stimulation on Cognitive Function and Upper Limb Motor Function in People With Chronic Stroke

Upper limb impairment is present in more than 85% of people with stroke, which greatly affect the quality of life, social participation, and performance of daily activities of people with stroke. Previous study also revealed that 53.4% of people after stroke experienced cognitive impairment. Different cognitive domains might be affected following stroke, such as attention, memory, language, and orientation, and the problems with memory are often prominent. Yet, there is no effective treatment for the post-stroke cognitive impairment.Transcutaneous electrical nerve stimulation (TENS) applied on thoracic region and transcutaneous vagus nerve stimulation (tVNS) are simple and non-invasive treatment to improve upper limb motor function and cognitive function. However, no existing studies have explored on the effects of TENS and tVNS on cognitive function in people with stroke. Therefore, the purpose of this study is to evaluate the effectiveness of TENS on improving upper limb function and cognitive function in people with chronic stroke. Also, this study will investigate the cortical response of people with stroke during TENS by using EEG power spectrum analysis.

Inclusion Criteria:aged between 50 and 80;have suffered from a single stroke at least 1 year;had volitional control of the non-paretic arm and at least minimal antigravity movement in the paretic shoulder;scored 7 or above in the Abbreviated Mental Test.Exclusion Criteria:have cardiac pacemaker or cochlear implant;have other neurological diseases;are taking medication that may affect measured outcomes;have skin lesions, infection, or inflammation near selected position;are participating in other drug/treatment programs.