Motor Imagery (MI) is defined as imagining an action in the mind without any explicit physical movement. MI is considered an "offline" process of the motor areas of the brain. Neuroimaging studies have shown that roughly the same neural structures play a role both during movement execution and MI. Specifically, these neural structures; supplementary motor area (SMA), premotor cortex (PMC), and in a growing number of studies, primary motor cortex (M1), inferior parietal lobe (IPL), basal ganglia, and cerebellum. In MI, the changes occurring in the Central Nervous System (CNS), such as the activation of the structures responsible for planning the movement and the purpose for which the movement will be performed, are similar to physical movement, but with the inhibition of the last motor neuron (primary motor area) responsible for revealing the movement, the movement is not physically performed and the motor visualization occurs.

During motor imagery, monitoring the quality of the individual's imagery session is very important for the effectiveness of the session. Additionally, studies have shown that giving the subject biofeedback regarding mental work can modulate the individual's mental work. For these purposes, the quality of an individual's motor imagery during a motor imagery session can be measured by biological measurement methods such as fMRI and autonomic nervous system response. In studies conducted on the autonomic nervous system response, changes in skin resistance and heart rate variations were observed. However, these methods are very costly and cannot be accessed in every clinic. In the literature, the Polar HRV device for measuring heart rate variability is a measuring device with proven validity and reliability and is easily accessible in terms of cost. However, we do not yet know whether Polar HRV is a valid and reliable measurement tool to measure the quality of an individual's imagery session during a motor imagery session.

This study aims to determine the effects of the individual's autonomic nervous system during the kinesthetic motor imagery session. To measure the responses and to investigate whether the polar HRV device is a valid and reliable tool.

Motor Imagery (MI) is imagining an action in the mind without any explicit physical movement. MI is considered an "offline" process of the motor areas of the brain. Neuroimaging studies have shown that roughly the same neural structures play a role both during movement execution and MI. Specifically, these neural structures; supplementary motor area (SMA), premotor cortex (PMC), and in a growing number of studies, primary motor cortex (M1), inferior parietal lobe (IPL), basal ganglia, and cerebellum. In MI, the changes occurring in the Central Nervous System (CNS), such as the activation of the structures responsible for planning the movement and the purpose for which the movement will be performed, are similar to physical movement, but with the inhibition of the last motor neuron (primary motor area) responsible for revealing the movement, the movement is not physically performed and the motor visualization occurs.

During motor imagery, monitoring the quality of the individual's imagery session is very important for the session's effectiveness. Additionally, studies have shown that giving the subject biofeedback regarding mental work can modulate the individual's mental work. For these purposes, the quality of an individual's motor imagery during a motor imagery session can be measured by biological measurement methods such as fMRI and autonomic nervous system response. In studies conducted on the autonomic nervous system response, changes in skin resistance and heart rate variations were observed. However, these methods are very costly and cannot be accessed in every clinic. In the literature, the Polar HRV device for measuring heart rate variability is a measuring device with proven validity and reliability and is easily accessible in terms of cost. However, we do not yet know whether Polar HRV is a valid and reliable measurement tool to measure the quality of an individual's imagery session during a motor imagery session.

This study aims to determine the effects of the individual's autonomic nervous system during the kinesthetic motor imagery session. To measure the responses and to investigate whether the polar HRV device is a valid and reliable tool.

Inclusion Criteria:

• Being 18-30 years old
• Volunteering to participate in the study
• Being seemingly healthy
• Not having any neurological or orthopedic disease
• Not having any vision, hearing, or speech problems that would prevent the tests from being performed.

Exclusion Criteria:

• Pregnancy and a history of any previous disorder or surgery that alters physical performance or physiological functions
• Have previous experience with Motor Imagery techniques or training
• People being treated with any medication that affects the central nervous system will not be included in the study.