Difficulties in Planning Among Patients with Multiple Sclerosis: A Relative Consequence of Deficits in Information Processing Speed

Abstract

Previous studies show that MS patients take longer than healthy controls to plan their solutions to Tower of London (TOL) problems but yield conflicting results regarding the quality of their solutions. The present study evaluated performance under untimed or timed conditions to assess the possibility that differences in planning ability only occur when restrictions in solution times are imposed. MS patients (n = 39) and healthy controls (n = 43) completed a computerized version of the TOL under one of two conditions. In the untimed condition, participants were allowed as much time as needed on each problem. In the timed condition, limits were imposed on solution times and time remaining was displayed with each problem. Patients exhibited longer planning times than controls, and the disparity between groups increased with problem difficulty. Planning performance depended upon condition. In the untimed condition, patients and controls performed equally well. When solution times were restricted, however, patients solved fewer problems than controls. MS patients' planning ability is intact when permitted sufficient time to formulate the required plan. Deficiencies in planning are only evident when time is restricted, and, therefore, are more accurately considered a relative consequence of disease-related problems in information processing speed.

Information processing speed in multiple sclerosis: Past, present, and future

“…The reviewed studies demonstrate the negative impact of IPS deficits on numerous aspects of cognition such as working memory (WM), 4–6 executive functions, 7–12 and learning and memory, 13 and identified IPS deficits as a predictor of several outcomes in persons with MS including employment, 14 driving, 15 instrumental daily activities (i.e. medication management, 16 quality of life, 17 and fall frequency 18 ).…”

Brain connectivity and cognitive processing speed in multiple sclerosis: A systematic review

“…Several studies investigated the impact of PS decline on cognition in people with MS. It was observed that in tasks of working memory [14,23], response inhibition [21], planning [20], task switching [24], and attention [25], after statistically controlling for PS performance, the differences between people with MS and healthy controls disappeared.…”

“…Deficits in executive functions [18] and, more specifically, in planning [19,20] and interference inhibition on the Stroop test [21,22] are associated with PS across the various clinical courses of MS.…”

Cognitive speed and white matter integrity in secondary progressive multiple sclerosis

“…Slowed PS has broader repercussions on performance in other cognitive domains [9][10][11][12][13][14][15].…”