Abnormalities of the executive control network in multiple sclerosis phenotypes: An fMRI effective connectivity study

Ekaterina Dobryakova, Maria Assunta Rocca, Paola Valsasina, Angelo Ghezzi, Bruno Colombo, Vittorio Martinelli, Giancarlo Comi, John Deluca, Massimo Filippi

Research output: Contribution to journalArticlepeer-review

Abstract

The Stroop interference task is a cognitively demanding task of executive control, a cognitive ability that is often impaired in patients with multiple sclerosis (MS). The aim of this study was to compare effective connectivity patterns within a network of brain regions involved in the Stroop task performance between MS patients with three disease clinical phenotypes [relapsing-remitting (RRMS), benign (BMS), and secondary progressive (SPMS)] and healthy subjects. Effective connectivity analysis was performed on Stroop task data using a novel method based on causal Bayes networks. Compared with controls, MS phenotypes were slower at performing the task and had reduced performance accuracy during incongruent trials that required increased cognitive control. MS phenotypes also exhibited connectivity abnormalities reflected as weaker shared connections, presence of extra connections (i.e., connections absent in the HC connectivity pattern), connection reversal, and loss. In SPMS and the BMS groups but not in the RRMS group, extra connections were associated with deficits in the Stroop task performance. In the BMS group, the response time associated with correct responses during the congruent condition showed a positive correlation with the left posterior parietal → dorsal anterior cingulate connection. In the SPMS group, performance accuracy during the congruent condition showed a negative correlation with the right insula → left insula connection. No associations between extra connections and behavioral performance measures were observed in the RRMS group. These results suggest that, depending on the phenotype, patients with MS use different strategies when cognitive control demands are high and rely on different network connections.

Original languageEnglish
JournalHuman Brain Mapping
DOIs
Publication statusAccepted/In press - 2016

Keywords

  • Bayes networks
  • Effective connectivity
  • Executive control
  • FMRI
  • Interference
  • Multiple sclerosis
  • Phenotypes
  • Stroop

ASJC Scopus subject areas

  • Clinical Neurology
  • Anatomy
  • Neurology
  • Radiology Nuclear Medicine and imaging
  • Radiological and Ultrasound Technology

Fingerprint Dive into the research topics of 'Abnormalities of the executive control network in multiple sclerosis phenotypes: An fMRI effective connectivity study'. Together they form a unique fingerprint.

Cite this