Neuropsychology of Multiple Sclerosis: Looking Back and Moving Forward

Abstract

The neuropsychological aspects of multiple sclerosis (MS) have evolved over the past three decades. What was once thought to be a rare occurrence, cognitive dysfunction is now viewed as one of the most disabling symptoms of the disease, with devastating effects on patients' quality of life. This selective review will highlight major innovations and scientific discoveries in the areas of neuropathology, neuroimaging, diagnosis, and treatment that pertain to our understanding of the neuropsychological aspects of MS. Specifically, we focus on the recent discovery that MS produces pathogical lesions of gray matter (GM) that have consequences for cognitive functions. Methods for imaging these GM lesions in MS are discussed along with multimodal imaging studies that integrate structural and functional imaging methods to provide a better understanding of the relationship between cognitive test performance and functional reserve. Innovations in the screening and comprehensive assessment of cognitive disorders are presented along with recent research that examines cognitive dysfunction in pediatric MS. Results of innovative outcome studies in cognitive rehabilitation are discussed. Finally, we highlight trends for potential future innovations over the next decade. (JINS, 2017, 23, 832-842)

<p>Patient Attitudes to Routine Cognitive Testing in Multiple Sclerosis</p>

“…Cognitive dysfunction (CD) has been reported to occur in 40-70% of MS patients. [1][2][3][4][5] CD may be seen at early disease stages and is not directly related to EDSS scores, yet tends to be more severe in progressive patients and to increase with disease duration. Even in mild CD, psychosocial, professional and daily functioning may be affected.…”

“…Even in mild CD, psychosocial, professional and daily functioning may be affected. [3][4][5][6][7] MS-related CD may involve any of the six core functional domains: perceptual-motor function, language, learning and memory, executive function, complex attention and social cognition and emotion regulation. [1][2][3]5,[8][9][10] Sub-types may co-exist, and CD often interacts with physical and affective MS symptoms such as stress, depression, fatigue or pain, hampering a clear establishment of causalities and confounders.…”

“…2,3,5,8,[11][12][13][14][15] CD in MS is thus a complex research field and much is still unclear with respect to both the primary and secondary causes of CD, and the ability of coping and cognitive reserve to mitigate the impact of brain atrophy. [1][2][3][4][5]7,11,12,16,17 Various neuropsychological tests have been developed to assess different domains of cognitive functioning. 1,[3][4][5]7,[17][18][19] Composite testing using multidimensional outcome measures improves the chances of identifying all relevant deficits, but they are challenging to apply in clinical practice.…”

“…[1][2][3][4][5]7,11,12,16,17 Various neuropsychological tests have been developed to assess different domains of cognitive functioning. 1,[3][4][5]7,[17][18][19] Composite testing using multidimensional outcome measures improves the chances of identifying all relevant deficits, but they are challenging to apply in clinical practice. 7,17,19 The brief Symbol Digit Modalities Test (SDMT) is recommended in terms of its sensitivity and clinical applicability.…”

“…Tablet-based testing will enable electronic transfer of data to patient records allowing to monitor changes over time. 1,4,[19][20][21] Consensus is lacking about when changing CD scores are clinically relevant and may lead to switch in treatment. 1 It is considered likely that disease-modifying treatments (DMTs) have positive effects through the general reduction in disease activity.…”