Assessing upper extremity-cognitive dual-task ability in neurological populations: A systematic review

BACKGROUND

Dual-task involves performing cognitive and motor tasks together, which requires executive functions that may be impaired in individuals with neurological conditions. Therefore, it is important to accurately assess executive functions to plan a therapeutic intervention.

OBJECTIVE

To characterize the use of upper extremity-cognitive dual-task assessment and to describe variables correlated with dual-task ability.

METHODS

An electronic search of databases (MEDLINE, EMBASE, CINAHL, and PsycINFO) was carried out using a combination of the following terms: upper-extremity, dual/concurrent task, and cognitive/motor tasks. Two reviewers independently completed data extraction and assessed study quality.

RESULTS

1,946 studies were identified; 25 studies met the inclusion criteria. The purpose of using an upper extremity-cognitive dual-task assessment varied between studies as well as the upper extremity motor tasks used: pegboard (N = 14), arm curl (N = 9), finger-tapping (N = 3), and reaching (N = 1) tests. Dual-task ability was reported as the motor-cognitive interference (N = 15) and as motor cost (N = 12). Dual-task ability was correlated to cognition, brain activity, and daily function, and was significantly different between healthy and neurological individuals.

CONCLUSION

Upper extremity cognitive dual-task paradigm is gaining popularity in clinical research, but lacks standardized tools, testing procedures, and calculations. A structured assessment procedure is needed for clinical use and future research.

Dual-Task Cost and Related Clinical Features in Patients With Multiple Sclerosis

This study aimed to investigate the dual-task cost of both motor and cognitive performances in patients with multiple sclerosis (PwMS) and in healthy controls and to determine their relationships with clinical features in PwMS. The participants performed motor tasks (postural stability, walking, and manual dexterity) and cognitive tasks (mental tracking and verbal fluency) under single- and dual-task conditions. The results showed that postural stability under dual-task conditions did not change, whereas walking and manual dexterity deteriorated, regardless of the concurrent cognitive task, in PwMS (median Expanded Disability Status Scale score: 1) and the healthy controls. Verbal fluency decreased during postural stability, whereas it increased during walking, and it was maintained during manual dexterity in both groups. Mental tracking did not change during walking; it declined during manual dexterity in both groups. Mental tracking during postural stability deteriorated in PwMS, while it did not change in the healthy controls. In general, dual-task costs were associated with baseline performances of tasks rather than clinical features. Therefore, baseline performances of both tasks should be increased for improving dual-task performance in PwMS.

Test-Retest Reliability of Cognitive-Motor Interference Assessments in Walking With Various Task Complexities in Persons With Multiple Sclerosis

Background. Simultaneous execution of motor and cognitive tasks can result in worsened performance on one or both tasks, indicating cognitive-motor interference (CMI). A growing amount of research on CMI in persons with multiple sclerosis (pwMS) is observed. However, psychometric properties of dual-task outcomes have been scarcely reported. Objective. To investigate the between-day test-retest reliability of the motor and cognitive dual-task costs (DTCs) during multiple CMI test conditions with various task complexities in pwMS and matched healthy controls (HCs). Methods. A total of 34 pwMS (Expanded Disability Status Scale score 3.0 ± 0.8) and 31 HCs were tested and retested on 3 single cognitive, 4 single motor, and 12 cognitive-motor dual tasks. Cognitive tasks included serial subtraction by 7, titrated digit span backward, and auditory vigilance. Motor tasks were walking at self-selected speed, over obstacles, crisscross, and while carrying a water-filled cup. Outcome measures were cognitive and motor DTC, calculated as percentage change of dual-task performance compared with single-task performance. Intraclass correlations (ICCs) and Spearman correlation coefficients were calculated as appropriate. Results. For DTCmotor of gait speed, ICCs ranged from 0.45 to 0.81 and Spearman correlations from 0.74 to 0.82. For DTCcognitive, ICCs ranged from −0.18 to 0.49 and Spearman correlations from −0.28 to 0.26. Reliability depended on the type of motor and cognitive task. Conclusion. Reliability of the DTCmotor was, overall, good, whereas that of the DTCcognitive was poor. The “walking” and “cup” dual-task conditions were the most reliable regardless of the integrated cognitive task.

Cognitive-motor interference in persons with multiple sclerosis during five upper limb motor tasks with different complexity

BACKGROUND

Cognitive-motor interference in multiple sclerosis has been well examined during walking, but not during upper limb (UL) performance.

OBJECTIVES

To examine the dual-task cost (DTC) in persons with multiple sclerosis (pwMS) and healthy controls (HC) in various type and complexity of UL motor tasks.

METHOD

In total, 30 pwMS without major UL impairment and 30 HC performed five different UL tasks, in single condition and combined with the phonemic word list generation task. The percent change in performances was evaluated by the motor, cognitive, and combined DTC. The motor tasks consisted of four unimanual (sustained hand grip strength, box-and-block test, Purdue pegboard test, finger tapping task) and one bimanual task (Purdue pegboard test). Group and task differences were analyzed with unpaired and paired t-tests, respectively, and overall effect with a multivariate analysis of variance.

RESULTS

The motor DTC ranged between 10% (Purdue pegboard bimanual) and 35% (box-and-block test). The cognitive DTC ranged between -8% (finger tapping test) and +21% (bimanual Purdue pegboard). The magnitude of the combined DTC did not differ significantly between pwMS and HC in any task.

CONCLUSION

DTC is influenced by the complexity of the UL task, but was not significantly different between HC and cognitive intact, but mildly motor disabled pwMS.