Table 1 Assessments used in the study

1

Montreal Cognitive Assessment (MoCA) [13]

A sensitive screening tool for detecting mild cognitive dysfunction

Assess several cognitive domains, including attention, concentration, executive functions, memory, language, visuospatial skills, abstraction, calculation, and orientation.

10 min

Highest score = 30. The cutoff score of 26 indicates normal cognition.

2

The Stroop Color and Word Test [14]

This executive function measure primarily assesses the ability to inhibit interference from distracting stimuli (i.e., selective attention) in a fixed time (i.e., processing speed). In this test, the subject is instructed to read the names of colors from three different conditions as fast as possible. In the first condition, the subject reads a list of color names printed in black ink (W = Word). Next, the subject is presented with a card containing shapes in different colors of ink, and the subject names the color of the ink (C = Color). In the third condition, the subject is given a card with color names written in an incongruent ink color (when the words and colors do not match). The subject is required to name the color of the ink instead of reading the word (CW = Color-Word). That is, the subject is required to inhibit the interference arising from reading the word (i.e., an automated task) and naming the color of the ink (i.e., an effortful task).

Selective attention and processing speed.

5 min

The number of correct answers in each condition (W, C, CW) in 45 s.

3

Comprehensive Trail making test (CTMT) [15]

The CTMT test uses a set of five standardized visual search and sequencing tasks (trials) to evaluate brain functions. The CTMT requires the participant to utilize visual scanning and sequencing abilities to draw lines to connect a series of stimuli (numbers or letters) in a specified order as fast as possible. We used Trial 1 (processing speed) and Trial 5 (alternating attention).

Processing speed and alternating attention

5 min

The primary score is the response time required to complete each trial. The norms for each trail are presented in the form of Percentile ranks and T-scores, which have a mean of 50 and a standard deviation of 10.

4

Wisconsin Card Sorting Test-64 (WCST-64) [16]

The WCST-64 is a measure of abstract thinking in which the participant has to classify cards with various geometric shapes in different colors and numbers according to different criteria (e.g., color, shape, or number). The participants are expected to accurately sort every response card with one of four stimulus cards through feedback (right or wrong) given to them based on a classification rule. The rule changes every few cards without prior notice, and the participant has to figure out the new rule. It is typical for the participant to start making one or more mistakes when the rule changes.

Executive function

10–15 min

Error scores, with lower scores indicating better executive function.

Perseveration errors (number of errors where the participant has used the same rule as the previous choice)

Non-perseveration errors (all remaining incorrect responses other than the Perseveration errors)

5

The Contextual Memory Test [17]

The participant is presented with pictures of 20 related objects for 90 s, as the items to be remembered. The participant is then requested to recall the objects immediately and again after 15 min.

Short-term memory and long-term memory

7 min

number of objects correctly recalled

6

The Digit Span Task [18]

In this test, the subjects are read a series of digits of increasing length and asked to repeat the same sequence back to the examiner in order (forward span) or reverse order (backward span). Forward span captures attention efficiency and short-term memory capacity. Backward span is an executive task particularly dependent on working memory.

short-term memory and working memory

10 min

The maximum number of forward or backward digits recalled without error

7

The d2 Test of Attention [19]

The participant is presented with a paper that has 14 rows, each comprised of 47 characters, for a total of 658 items. The participant is instructed to scan each row and cross out any letter “d” that has two dashes, which can be above or below the letter “d” in any order while ignoring/suppressing irrelevant distracters. The distractors are orthographically similar stimuli (the letters “p” or “d” with 1–4 dashes over and under each letter). The participant is allowed 20 s per row before moving to the next one, with no pauses allowed between rows

processing speed, selective attention, sustained attention, and quality of visual scanning performance in response to the discrimination of similar visual stimuli.

8 min

Total number of items processed (TN): The aggregated number of processed items (both correct and incorrect) from each raw. This is a measure of processing speed.

Omission errors (OE): The number of missed correct items. This is a measure of processing accuracy (carelessness).

Commission errors (CE): The number of incorrect items crossed out. This is a measure of processing accuracy (impulsivity), with lower scores indicating better function.

Total number of errors (TE): Total number of commission and omission errors (OE + CE).

Total performance (TP): The difference between the total number of items processed and the total number of errors (TN-TE). This is a measure of the balance between processing speed and accuracy of attention mechanisms.

8

Grooved Pegboard [20]

The grooved pegboard device is a symmetrical board with 25 slotted holes in a 5 × 5 matrix. In this test, the participant is instructed to rotate and place grooved metal pegs into holes with matching slots, which are angled in different directions. The pegs must be inserted one at a time and as quickly as possible with their dominant hand without practice trials

Fine motor dexterity

5 min

The time required to complete 25 pegs.