Computerized Attention Functions Training Vs. Executive Functions Training for Children with ADHD

sustained attention

The CCPT (Conjunctive Continuous Performance Test ) was used to assess sustained attention. In this task, a series of geometric shapes of different colors were displayed on the monitor, and the participants were asked to press the spacebar each time the target stimulus (i.e., red square) appeared, and delay their responses when other stimuli, other than the target stimulus, were displayed. The task consisted of a single block of 320 trials, in which the target stimulus appears in only 30% of trials. Performance was measured by two important measures that are frequently used to evaluate sustained attention: (a) standard deviation of response times (SD of RT), calculated only for correct responses, which reflects inconsistency in RTs to targets; and (b) percentage of omission errors - in which the participant did not respond to the target stimulus. High values in these measures indicate a difficulty in sustained attention.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

sustained attention

The Go/No-go Task. was also used to assess sustained attention. The task is similar to the CCPT except that the target stimulus appears in 70% of the trials (see Figure 3b for a schematic diagram of the task). Performance was measured by the same measures as the CCPT: (a) SD of RT; and (b) omission error rate.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

selective-spatial attention

Conjunctive Visual Search Task (CVST). This task was designed to assess selective-spatial attention. In this task participants were asked to search for a blue square that appeared among an equal number of red squares and blue circles. There were four display sizes of 4, 8, 16 or 32 items, which were equally frequent and randomly intermixed within four 40-trial blocks. Participants were required to respond with their right index finger to the presence of the target and with their left index finger to its absence. RTs and accuracy rates were recorded for each display size with and without a target.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

executive attention - conflict resolution

We used a Location-Direction Stroop-like Task (LDST) to assess executive attention - conflict resolution. The participants were instructed to make two types of judgment that referred to either the location or the direction of an arrow appearing on the screen. This arrow appears either above or below a fixation point and points upward or downward. On the first sub-task the participants were asked to respond only to the location of the arrow, while ignoring the arrow's direction. In the second sub-task the participants were asked to respond only to the direction of the arrow, while ignoring its location. Responses in both sub-tasks were the same - participants were directed to respond ''up'' with their right index finger and ''down'' with their left index finger. Each sub-task was comprised of two 40-trials blocks. Half of the trials within each block were congruent (e.g., an arrow located above the fixation point and directed upward) and half were incongruent.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

problem solving

A computerized version ofTower of Hanoi Puzzle was used to evaluate problem solving ability. In this task, three pegs, numbered 1 to 3, appeared on the screen. On one of the pegs, three disks were arranged according to their size (i.e., the largest disk at the bottom and the smallest disk on top). The participants were instructed to move the disks from a starting position peg to a final position peg as fast as possible and with the least number of moves as possible, while using a third peg for their disposal. They were also asked to abide by three rules: (a) only one disk can move from peg to peg in each move; (b) a larger disk cannot be placed on top of a smaller one; and (c) all three pegs must be used.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

auditory working memory capacity

The task WISC-IV Digit Span Forward was used to evaluate auditory working memory capacity. In this task, the participants were required to listen to and repeat a sequence of numbers read aloud by the research assistant. The task starts with the sequence length of only two digits and gradually increases in length up to nine digits. Participants have two chances at each sequence length, and the next length sequence is read to them only if one of the sequences in the previous length was repeated correctly. The measure we used for this task is the summary score, computed as the longest sequence remembered, multiplied by the number of correct sequences.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

manipulation verbal information

We used the WISC-IV Digit Span Backward to evaluate the ability to manipulate verbal information while in temporary storage, namely, working memory's Central Executive. This task is very similar to the WISC-IV digit span forward, accept for two differences: (a) participants are asked to repeat the digits' sequence in the reversed order; and (b) the longest sequence is of eight digits.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

visuospatial working memory capacity

We used a computerized version of the Corsi-Block Tapping Task Forward, to evaluate visuospatial working memory capacity. In this task, the participants were presented with a screen of 9 blocks. The blocks light up in a pre-fixed sequence, and the participants were instructed to click the blocks on the screen, using the computer mouse at the same order they were lit. The task starts with the sequence length of only two blocks and gradually increases in length up to nine blocks. Participants have two chances at each sequence length, and the next sequence length starts only if one of the sequences in the length before was repeated correctly. We also used Corsi-Block Tapping Task Backward to evaluate visuospatial working memory capacity. The task is very similar to the Corsi-Block Tapping Task Forward accept for two differences: (a) participants are asked to click on the blocks in the reversed order of their original presentation; and (b) the longest sequence is of eight blocks.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

Fluid Intelligence

Fluid intelligence was evaluated by using the Raven's Colored Progressive Matrices. This test is designed for young children aged 5-11 years old, and consists of 36 items in three sets (A, AB, B), with 12 items per set. The three sets are arranged to assess the cognitive processes of which children under 12 years of age are usually capable of. The Raven's CPM produces a single raw score that can be converted to a percentile based on normative data.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

Arithmetic

Arithmetic Task was comprised out of 40 arithmetic exercises that require utilizing the four basic operations: 20 exercises requiring adding and subtracting up to 20, and 20 exercises requiring multiplying and dividing up to a 100, intermixed. Participants were asked to solve as quickly and accurately as possible all exercises. Two measures were calculated out of this task: (a) speed - total time to finish the task (in sec); and (b) accuracy - the percentage of correct answers out of 40. The task was developed specifically according to the needs of this research.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

Text Reading

Participants were asked to read aloud as fast and as accurate as possible, a Hebrew text that does not include syntactic movement. Prior to the administration of the task, the research assistant ensured the participants that they would not be asked questions regarding the content of the text, nor would they need to remember details from it. The research assistant recorded the participants' reading, documented their mistakes, and timed them. The main measures that were calculated for this task are: (a) the number of words read per minute (i.e., speed); and (b) the percentage of words read correctly.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

Writing from Dictation

The research assistant dictated to the participants a text in Hebrew that included homophonic and pseudo-homophonic words. The participants were asked to write what was dictated to them as fast and as accurate as possible on a loose-leaf line paper. Two measures were calculated out of this task: (a) the number of words written per minute (i.e. speed); and (b) the percentage of words written correctly from all written words (i.e., accuracy).

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)

Behavioral, Emotional and Social Performance

Parents completed three questionnaires online via Qualtrics: 1. Attention Deficit Hyperactivity Disorder Rating Scale-IV (ADHD-RS-IV). 18 items rated on a 4-point scale (0 = never/rarely, 3 = very often). Range: 0 to 54, with higher scores indicating more severe ADHD symptoms. 2. Child Behavior Checklist (CBCL). 113 items assessing 8 behavior syndromes. Range: depends on subscale, with higher scores indicating more problematic behaviors. 3. Behavior Rating Inventory of Executive Function (BRIEF). 86 items assessing executive function on 8 subscales. Range: depends on subscale, with higher scores indicating more dysfunction.

Time frame: Baseline, post-intervention, follow-up (approximately 3 months after intervention)