The Influence of Rhythm, Cognitive Task and Physical Activity on the Cardiac ANS in Chronic Stroke Patients

Autonomic dysfunction is a common complication of stroke that may lead to poor rehabilitation outcomes and to increase in mortality. The severity of the autonomic dysfunction can be measured in many ways, but the most common way is assessment of the sympathetic-parasympathetic equilibrium by heart rate variability analysis. It is known that the plasticity of the brain can influence the autonomic nerve system and that providing appropriate stimuli encourages these changes. It was found that stimulation of rhythm, stimulation of cognitive tasks and stimulation of activity, influence the autonomic nerve system in healthy subjects. Thus, we can ask if an integrated task (activity, cognitive, rhythm) may influence the autonomic nervous system and cause an increase in brain activity, therefore contributing to the rehabilitation of stroke patients. Taken together, the purpose of this study is to examine the influence of stimulation of rhythm, stimulation of cognition, stimulation of activity and combined stimulation, on the autonomic nerve system. This effect will be tested by measuring heart rate variability in chronic stroke patients and in a control group.

background and Rationale: Autonomic dysfunction is a common complication of stroke that may lead to poor rehabilitation outcomes and to increase in mortality. Although this dysfunction is a common symptom of stroke, both in the acute phase and in the chronic phase, it is not a specific therapeutic target yet. The severity of the autonomic dysfunction can be measured in many ways, but the most common way is assessment of the sympathetic-parasympathetic equilibrium by heart rate variability analysis. It is known that the plasticity of the brain can influence the autonomic nerve system and that providing appropriate stimuli encourages these changes. It was found that stimulation of rhythm, stimulation of cognitive tasks (in particular, stimulation of executive functions) and stimulation of activity, influence the autonomic nerve system in healthy subjects. Thus, we can ask if an integrated task (activity, cognitive, rhythm) may influence the autonomic nervous system and cause an increase in brain activity, therefore contributing to the rehabilitation of stroke patients. Taken together, the purpose of this study is to examine the influence of stimulation of rapid or slow rhythm, stimulation of cognition by cognitive tasks, stimulation of activity by pedaling a fitness bike and combined stimulation, on the autonomic nerve system. This effect will be tested by measuring heart rate variability in chronic stroke patients and in a control group with equivalent age and lifestyle.

The Medical Device:

Heart rate and heart rate variability will be monitored by Polar RS800CX watch (PolarElectro OY, Kempele, Finland(. A transmitter placed on the patient's chest will collect the data. This data will be stored in the watch's computer and then analyzed in a specific Polar software (Polar Protrainer 5 inc.). An appropriate filtration will be made after a preliminary study. Pedaling capability, RPM, will be collected from cadence sensor with Bluetooth smart.

The Purpose of this Medical Research:

The purpose of this study is to examine the influence of stimulation of rapid or slow rhythm, stimulation of cognition by cognitive tasks, stimulation of activity by pedaling a fitness bike and combined stimulation, on the autonomic nerve system in chronic stroke patients and in a control group with equivalent age and lifestyle.

Eligibility Criteria:
Inclusion Criteria:

* All participants will be \> 60 years, have Clalit health insurance, walking and Hebrew native speakers. Number of man and woman participating in the study will be equal.

Exclusion Criteria:

* Individuals with any of the following criteria will not participate in the study: participants with communication problems such as language, hearing or visual problems, recurrent strokes, cognitive deficiency (MoCA≤ 26) (Toglia et al., 2011), neglect by BIT - Star cancellation test (Wilsonet et al., 1987), patients with central or peripheral neurological problems, heart pacemaker and/or patients that use medications that effect the autonomic nerve system such asβ blockers, or use alcohol or drugs.
* Patients that suffer from background illness that can effect their ability to cycle such as knee OA.