Pediatric patients with multiple sclerosis acquire average intelligence quotient levels, but exhibit reduced resting-state functional connectivity (RS-FC) in language, memory, and motor networks, according to study findings presented at the 2022 American Academy of Neurology (AAN) Annual Meeting, held from April 2 to April 7 in Seattle, Washington, and virtually from April 24-26, 2022.
Pediatric MS is unlike adult-onset MS in that the developing brain has greater compensatory mechanisms, yet the pathology of MS can interfere with the brain’s development. The objective of the current study was to assess the neuropsychological profile of pediatric MS and its association with RS-FC abnormalities in cognitive and motor networks.
Researchers included 76 pediatric patients with MS in the 3.0 T RS functional magnetic resonance imaging (MRI) study. The patients underwent neuropsychological testing of global cognition through the Wechsler Intelligence Scales’ intelligence quotient examination. They assessed set-shifting with Trial Making Test A and B (TMT-A, TMT-B), language through the semantic and phonemic fluency tests (SVFT, PVFT), and visual-motor coordination through the Symbol Digit Modalities Test (SDM), Coding (CD) and Block Design (BD). The researchers also compared the patients with 22 age- and sex-matched healthy control individuals.
To calculate RS-FC within the executive, language, memory, and motor networks, the researchers used seed-based correlation. They assessed between-group differences and correlations with cognitive scores with age- and sex-adjusted full-factorial models.
The median IQ of pediatric MS patients was 97.5 and18.4% of the patients scored below the normative average, 84. About 1 of every 5 patients failed the CD. Roughly 13% of patients failed the TMT-B, and about 12% of patients failed the TMT-A.
Patients with MS tended to have lower RS-FC of the bilateral caudate nucleus and higher RS-FC of the bilateral precentral gyrus in all networks compared with healthy control individuals. They had lower RS-FC in several network-specific areas, including the anterior cingulate cortex (language network) and the angular gyrus (memory and motor networks).
Reduced RS-FC of the caudate nucleus was linked with higher IQ and TMT-A/B scores but lower scores on BD and CD tests. When the anterior cingulate cortex had lower RS-FC, scores on the SVFT, CD, and SDMT tended to be higher.
“Pediatric MS patients achieve average IQ levels,” the researchers concluded. “Reduced RS-FC of the caudate nucleus contributes to global cognitive efficiency but also to patients’ fragility in processing speed associated with visual-motor coordination skills.”
Reference
Cacciaguerra L, Curatoli C, Vizzino C, et al. Functional MRI correlates of intelligence quotient and visual-motor coordination in pediatric multiple sclerosis. Presented at: the 2022 AAN Annual Meeting; April 2-7, 2022; Seattle, Washington; April 24-26, 2022; Virtual Meeting. Abstract P1.003.
This article originally appeared on Neurology Advisor