Dual-Task Stroop Paradigm for Detecting Cognitive Deficits in High-Functioning Stroke Patients

Our study protocol could be used to identify cognitive deficit in high functioning stroke patients who are not easily detected by conventional assessment skills. This study protocol is to provide new ideas to figure out effect in general clinical assessment failure for high functioning stroke patients. This study protocol could be easily used in the clinical practice.

For example, the clinician could modify the treatment strategy based on the Stroop reaction time and the correct rate. Demonstrating the procedure will be Siqi Huang, rehabilitation therapist;Siqing Wang, occupational therapist;Yajie Zhanga, physical therapist, Biyi Zhao, occupational therapist from our lab. Recruit stroke patients with stable conditions at Brunnstrom Stage 4 as confirmed by imaging examination.

Ensure that the subjects participate in the test voluntarily and sign an informed consent form. Record the information of the participant, including name, gender, date of birth, education level, body mass index, medical history, and medication history. For cognitive assessment, perform MoCA on the participants by asking 11 questions addressing their attention and concentration, executive function, memory, language, visual structure skills, abstract thinking, computing, and orientation.

Then perform CDR by collecting information during structured interviews with the participants and their families to assess the abilities of the participants in aspects such as memory, orientation, judgment and problem solving, work and social interaction, family life, personal hobby, and independent living. Perform Albert's Test to detect the presence of unilateral spatial neglect in patients with stroke. Ask the subject to cross out all the lines that are placed in random orientations on a piece of paper.

Next, perform Fugl-Meyer Assessment on the participants to assess sensation, balance, joint range of motion, and joint pain in patients with post-stroke hemiplegia. The motor function includes items assessing movement, coordination, and the reflex actions of the shoulder, elbow, forearm, wrist, hand, hip, knee, and ankle. Also perform Berg Balance Scale on the stroke patient with a total of 14 items from easy to difficult including sitting balance, standing balance, body transfer, turning, and single leg standing.

Perform the timed up and go test. Ask the subject to stand up from the chair, walk for three meters, turn their body, then return and sit in the chair. Concurrently, time the whole process from issuing the departure order to sitting in the chair.

Prepare the participant by ensuring that the CZ site at the top of the test cap, which is the fourth point from the forehead to the occipital lobe, is on the midline of the full cap. Ensure that the midpoint of the connection lies between the nasal root to the lower edge of the occipital protuberance, the connection between the superior auricular fossa of both ears or the intersection point of the connection from the nasal root to the occipital protuberance. Then click the pre-acquisition button to start pre-acquisition and calibrate the test signal.

Perform Stroop single task evaluation synchronized with fNIRS. Then perform Stroop dual task evaluation synchronized with fNIRS. First, ask the patient to sit in a stable chair.

Run the commercial stimulus presentation software and select the congruence test trials. Make a new profile for the patient. Select the congruence test trials of the Stroop task and repeat three trials.

In the resting stage, ask the patient to relax. When the experiment is in the stimulation stage, ask the patient to perform the attention related test and complete the task in six seconds. The patient should complete it 10 times in 60 seconds.

Ask the patient to follow the instructions for the two test trials. Select the congruence test trials. Click the arrow button to the left when left is shown.

Click the arrow button to the right when right is shown. Select the incongruence task trials. Click the arrow button to the left as soon as possible when right is shown on the left of the square.

Click the arrow button to the right as soon as possible when left is shown on the right of the square. Finish the task, save the data and export the data to a self-built database. To perform the Stroop dual task evaluation, ask the patient to sit on a balance ball.

Let the patient complete the Stroop experimental paradigm with the steps shown in the previous step. When the experiment is in a resting stage ask the patient to keep balance and relax on the balance ball. When the experiment is on stimulation, ask the patient to carry out the attention related test while maintaining balance on the balance ball as much as possible.

This study presents cognitive assessment of a high functioning stroke patient compared to a healthy subject. In dual task congruence test trials, the reaction time of the stroke patient was higher than that of a healthy young subject and their accuracy was relatively lower. This difference was greater in the incongruence test trials.

The results for brain function showed that the beta value of the regions of interest in the stroke patient was lower than that in the healthy young subject while performing dual task Stroop. Blood oxygen concentration in brain regions was shown. The beta values in the stroke patient were lower than that in the healthy young subject during dual task performance.

During the dual task case, the evaluator should protect participant to avoid occurrence of accidental injuries such as falling. Our study protocol was mainly used to evaluate acuity function. The different types and difficult levels of dual tasks should be studied in the future.

Dual task assessment in our study protocol could identify cognitive deficit in high functioning patients which will pave the way for the development of individualized treatment plans.