Subcortical grey matter structures in multiple sclerosis

Abstract

The present study aimed to investigate altered grey matter (GM) and functional connectivity (FC) in deep subcortical areas, such as the thalamus and basal ganglia, and their relationship with cognitive impairment (CI) in multiple sclerosis (MS). Thirty-six patients were neuropsychologically assessed, classified as cognitive preserved (CP) and CI, and were compared with 18 healthy controls. GM atrophy and FC were observed in 10 predefined functional areas of the thalamus and in six of basal ganglia. GM atrophy was prominent in the basal ganglia in CI patients compared with CP MS patients. Increased FC was observed between the right caudate and the bilateral orbitofrontal cortex in CI versus CP patients. The discriminant and correlation analyses showed that the enhanced FC observed between the right caudate and the orbitofrontal cortex was closely associated with CI in MS patients. In conclusion, reduced GM volume and enhanced frontobasal ganglia connectivity are related to cognition in MS patients.

A systematic review of resting state functional MRI connectivity changes and cognitive impairment in multiple sclerosis

“…Studies of cognition in MS use a vast array of definitions of cognitive impairment (7–9), as reflected in this review. For example, of the studies using the BRB-N to assess cognitive function, most use a more conservative definition of cognitive impairment of at least 2 SDs below controls on 2 or more tests (23,36,67–73), but other, less conservative definitions are used too (37,74,75). The definition of cognitive impairment has been shown to have effects on underlying FC alterations of MS CI by the classification used (76).…”

“…BRB-N to assess cognitive function, most use a more conservative definition of cognitive 3 impairment of at least 2 SDs below controls on 2 or more tests(23,36,(67)(68)(69)(70)(71)(72)(73), but other, less 3 conservative definitions are used too (37,74,75). The definition of cognitive impairment has been3 shown to have effects on underlying FC alterations of MS CI by the classification used (76).…”

A Systematic Review of Resting-State Functional MRI Connectivity Changes and Cognitive Impairment in Multiple Sclerosis

“…Studies of cognition in MS use a vast array of definitions of cognitive impairment (7-9), as reflected in this review. For example, of the studies using the BRB-N to assess cognitive function, most use a more conservative definition of cognitive impairment of at least 2 SDs below controls on 2 or more tests (23,36,(67)(68)(69)(70)(71)(72)(73), but other, less conservative definitions are used too (37,74,75). The definition of cognitive impairment has been shown to have effects on underlying FC alterations of MS CI by the classification used (76).…”

Women in the field of multiple sclerosis: How they contributed to paradigm shifts

“…Specifically, male MS patients showed a higher degree of GM volume in the bilateral frontal areas and increased functional connectivity as a compensatory mechanism when compared with female patients (Sanchis-Segura et al, 2016). Moreover, in another study, it was shown that GM loss in the thalamus and basal ganglia was associated with worse cognition in MS (Cruz-Gomez et al, 2018).…”

“…In fact, they found a strong correlation between overall dysfunction and longer MRI changes in several cortical areas that strikingly overlap with regions of the default-mode network, known to be highly critical for attention and memory (e.g., precuneus/posterior cingulate cortex that forms a major hub, medial prefrontal cortex, medial temporal lobe, and lateral and inferior parietal cortex) (Louapre et al, 2016). It was shown that GM loss in the thalamus and basal ganglia is associated with worse cognition in MS (Cruz-Gomez et al, 2018). Furthermore, Cristina Forn reported that GM atrophy is circumscribed to the bilateral posterior cingulate gyrus/precuneus in patients with early MS (Baltruschat et al, 2015).…”