Cognitive-motor Interference in Persons With MS

Dual tasking such as walking while talking on the phone or while remembering a shopping list is very frequently required in everyday life. Cognitive-motor interference occurs when the performance capacity of a motor or cognitive task decreases when both are performed simultaneously (dual task) compared to single task execution being the so-called dual task cost (DTC). Over the past five years, in MS, (pilot) studies have been conducted in order to investigate the presence and magnitude of the CMI during walking. It was shown that, even in the early stages of the disease, when walking speed is not affected as a single motor task, pwMS slow down more than healthy controls when performing DT walking. Studies have not yet investigated the impact of the complexity of the motor task, on the DTC. Across studies, many different types of cognitive distractors were applied without any documentation of psychometric properties, such as test-retest reliability, making it not yet suited as experimental outcome measure. Results have also focused on the effects of DT on walking performance, while the performance of the cognitive task was rarely assessed. Also, the majority of studies did not document the cognitive function level of pwMS or even excluded patients with cognitive deficits. As such, the relation between cognitive deficits and dual task (cognitive-motor) performance is unclear.

Motor and cognitive impairment are currently also treated separately whereas real life performance very often requiring an integrated motor and cognitive function. So far, no studies in MS have investigated the effects of physical or cognitive exercises on DT performances, or investigated effects of integrated cognitive-motor dual task training (DTT). In elderly and other neurological conditions, superior effects of dual task training (DTT) on gait training have been suggested, but the evidence is not robust yet. All these studies suggest the feasibility of DTT on gait improvement and fall risk reduction, but further insights on factors identifying responders, and differential effect of cognitive distractors needs further elucidation.

This research consist of two parts that aim to investigate:

Part 1: Assessment

1. the magnitude of the dual task cost according to different types of cognitive distractors (information processing, memory, attention, etc.),
2. its reliability as experimental outcome measure and
3. its association with factors as severity of cognitive or motor dysfunction, quality of life and fatigue.

Part 2: Intervention

1. the effectiveness of cognitive-motor DT-based training programs compared to single modality training, on DT and ST performances (cognition and mobility)
2. whether dual task learning effects transfer to improvements in daily life and are sustained for 4 weeks without training
3. which patient profiles benefit most from the integrated cognitive-motor training
4. feasibility and usefulness of an adaptive, interactive ICT-guided DTT system.


Eligibility Criteria:
Inclusion Criteria:

* Diagnosis of MS according to McDonald criteria
* EDSS ≥2 and ≤ 6
* No relapse within the last 30 days
* No changes in disease modifying treatment and no corticoid-therapy within the last 50 days
* All types of MS
* Minimal cognitive functioning (MMSE≥26)
* Presence of dual task interference (dual task screening list ≥1)

Exclusion Criteria:

* Other medical conditions interfering with mobility
* Other neurological diagnoses
* MS-like syndroms such as neruomyelitis optica
* Not able to understand and execute simple instructions
* Problems (even after adjustment with hearing aids or glasses) with hearing or vision interfering with the assessment or training.
* Ongoing dual task training or other interfering physical therapy or cognitive training/neuropsychological rehabilitation.