The Relationship between Specific Cognitive Domains, Fear of Falling, and Falls in People with Multiple Sclerosis

Table 1

MindStreams global assessment battery (GAB): description of cognitive domains tested and outcome parameters obtained.

GAB test	Cognitive domains tested	Test description	Outcome parameters
Go-NoGo response inhibition	Executive function, attention	Timed continuous performance test during which responses are made to large colored stimuli that are any color but red.	Accuracy; Average response time; Response time standard deviation; Errors of commission; Errors of omission; Response time for errors of commission
Verbal memory	Memory	Ten pairs of words (the study set) are presented, followed by a recognition test in which one member (the target) of a previously presented pair appears together with a list of four candidates for the other member of the pair. There are four immediate repetitions and one delayed repetition after 10 minutes.	Immediate recognition; Accuracy, repetition 1 to 4; Accuracy, repetitions 1–4; Delayed recognition; Accuracy
Nonverbal memory	Memory	This is similar to the verbal memory test, except that geometric figures are used instead of words.	Immediate recognition; Accuracy, repetition 1 to 4; Accuracy, repetitions 1–4; Delayed recognition; Accuracy
Problem solving	Executive function	Pictorial puzzles of gradually increasing difficulty are presented. Each puzzle consists of a 262 array containing three black-and-white geometric forms with a certain spatial relationship among them and a missing form. Participants must choose the best fit for the fourth (missing) form from among six possible alternatives.	Accuracy (nonverbal IQ)
Stroop interference	Executive function, attention	Timed test of response inhibition and set shifting. For example, in the “No Interference [Meaning]” phase, the task is to choose the color named by a word presented in a white letter-color. In the final (“Interference”) phase, participants choose the letter-color of a word that names a different color.	No interference: letter color; accuracy; Average response time; Response time standard deviation; No interference: word meaning; accuracy; Average response time; Response time standard deviation; Interference: letter color versus word; Meaning; Accuracy; Average response time; Response time standard deviation
Finger tapping	Motor skills	Participants must tap on the mouse button with their dominant hand.	Inter-Tap Interval; Tap Interval Standard Deviation
Catch game	Executive function, motor skills	A test of motor planning requiring hand-eye coordination and rapid responses. Subjects ‘‘catch’’ a ‘‘falling object’’ by moving a ‘‘paddle’’ horizontally on the computer screen so that it can be positioned directly in the path of the falling object.	Time to make 1st move; Time to make 1st move standard; deviation; Average direction changes per trial; Average error for missed catches; Total score
Information processing speed	Attention, information processing speed	This test comprises three levels of an information processing load: single digits, two-digit arithmetic problems (e.g., 5 − 1), and three-digit arithmetic problems (e.g., 3 + 2 − 1). For each of the three levels, stimuli are presented at three different fixed rates, incrementally increasing as testing continues. Participants are instructed to respond as quickly as possible by pressing the left mouse button if the digit or result is less than or equal to 4 and the right mouse button if it is greater than 4.	SINGLE DIGIT; Slow speed, medium speed, fast speed; Accuracy; Average response time; Response time standard deviation; TWO-DIGIT ARITHMETIC; Slow speed, medium speed, fast speed; Accuracy; Average response time; Response time standard deviation; THREE-DIGIT ARITHMETIC; Slow speed, medium speed, fast speed; Accuracy; Average response time; Response time standard deviation
Verbal function	Verbal function	Pictures of common objects are presented; in the first phase, the word that best rhymes with the name of the object must be selected from among four choices; in the second phase, the name of the picture must be selected.	Rhyming; Accuracy, high and low familiarity; Naming; Accuracy, high and low familiarity
Visual spatial processing	Visual spatial	Computer-generated scenes containing a red pillar are presented. Participants must select the view of the scene from the vantage point of the red pillar.	Accuracy

Index scores explanation for GAB cognitive tests.
(1) MEMORY: mean accuracies for learning and delayed recognition phases of Verbal and NonVerbal Memory tests.
(2) EXECUTIVE FUNCTION: composite scores (accuracy divided by average response time) for interference phase of the Stroop test and Go-NoGo test, mean weighted accuracy for catch game.
(3) VISUAL SPATIAL: mean accuracy for Visual Spatial Processing test.
(4) VERBAL FUNCTION: weighted accuracy for verbal rhyming test (part of Verbal Function test).
(5) ATTENTION: mean response times for the Go-NoGo test and a no interference phase of the Stroop test, mean response time for a low-load stage of Information Processing test, mean standard deviation of response time for the Go-NoGo test, and mean accuracy for a medium-load stage of Information Processing test.
(6) INFORMATION PROCESSING: composite scores (accuracy divided by average response time) for various low- and medium-load stages of the Information Processing test.
(7) MOTOR SKILLS: mean time until first move for catch game, mean intertap interval, and standard deviation of intertap interval for Finger Tapping test.