Mental Imagery on Upper Extremity Skills

Mental Chronometry: Mental chronometry is a method that measures imagery time, considered more objective than questionnaires in the assessment of MI. It examines the time difference between the actual physical execution of a movement and the mental image of the same movement.

The Nine-Hole Peg Test (9PPT) is frequently used in the literature, although its validity and reliability as a mental chronometry test are lacking. In this task, the participant is required to remove nine pegs from the board to which they are fixed as quickly as possible and place them in a container on the board. The pegs used in the test (8 mm in diameter, 3 cm long) can be made of wood or plastic. The board (23 cm long, 10 cm wide, and 2 cm high) has a section at one end where the pegs are fixed (arranged in a 3x3 matrix) and a container-shaped space on the side for the pegs to be placed. Participants perform the test on both upper extremities. Before the test, all participants are given the opportunity to ho

Medical history (disease duration and symptoms), demographic information, will be recorded.

PD disability will be assessed with the m-HY scale. All of the patients with PD will be staged according to the Hoehn Yahr scale as follows: stage 1.0 (unilateral involvement only); stage 1.5 (unilateral and axial involvement); stage 2.0 (bilateral involvement without balance impairment); stage 2.5 (mild bilateral disease with improvement in the pull test); stage 3.0 (mild to moderate bilateral disease; some postural impairment; physically independent); stage 4.0 (severe disability; still able to walk or stand unaided).

Symptom severity in PD is rated using the Unified Parkinson's Disease Rating Scale (UPDRS). Several items on this scale assess upper extremity and hand function. The Activities of Daily Living section assesses handwriting, cutting food, and grasping utensils. The Motor section assesses finger tapping, hand movements, and rapid alternating hand movements. These test items are scored from 0 to 4, with 4 representing maximum impairment and 0 representing normal movement ability. The UPDRS sections are subdivided into: Section I (mental dysfunction and mood); Section II (activities of daily living); Section III (motor); and Section IV (treatment-related complications).

This test was developed by Folstein in 1975. Its Turkish validity and reliability study was conducted by Güngen et al. in 2002. The MMSE, which is quite suitable for screening cognitive function in the elderly and assesses cognitive functions in five separate areas (orientation, registration, attention and calculation, recall, and language), is frequently used. A score below 24 on the MMSE indicates dementia, 24-26 indicates mild cognitive impairment, and 26 or above indicates normal cognitive function.

Isometric strength will be measured using a digital muscle strength measurement device (KFORCE KINVENT) for the bilateral serratus anterior, upper trapezius, latissimus dorsi, deltoid, supraspinatus, teres minor, subscapularis, and biceps brachii muscles of the upper extremity.

A Jamar hand dynamometer (Baseline®) (and a PinchMeter (Baseline Mechanical Pinch Gauge with Case, Blue, 30 lb) will be used for grip strength measurement.

The Kinesthetic and Visual Imagery Questionnaire (KVIQ), Short Form, was developed to determine the extent to which individuals visualize and feel imaged movements. It consists of a total of 10 movements measuring five visual and five kinesthetic imagery skills (23). The questionnaire is not a self-report measure but is administered by an assessor. All movements are assessed in a sitting position. The assessor first performs the relevant movement on themselves, and then the participant is asked to perform the same movement only once. The participant then imagines the movement and is asked to rate the visual clarity or intensity of sensations of the imagined movement using a five-point ordinal scale. Higher scores indicate greater visual clarity or intensity of sensations. This questionnaire will be used to assess mental imagery ability in our study.