title: Multiple sclerosis decreases explicit counterfactual processing and risk taking in decision making.
abstract: BACKGROUND
  Deficits in decision making (DM) are commonly associated with prefrontal cortical damage, but may occur with multiple sclerosis (MS). There are no data concerning the impact of MS on tasks evaluating DM under explicit risk, where different emotional and cognitive components can be distinguished.
  
  
  METHODS
  We assessed 72 relapsing-remitting MS (RRMS) patients with mild to moderate disease and 38 healthy controls in two DM tasks involving risk with explicit rules: (1) The Wheel of Fortune (WOF), which probes the anticipated affects of decisions outcomes on future choices; and (2) The Cambridge Gamble Task (CGT) which measures risk taking. Participants also underwent a neuropsychological and emotional assessment, and skin conductance responses (SCRs) were recorded.
  
  
  RESULTS
  In the WOF, RRMS patients showed deficits in integrating positive counterfactual information (p<0.005) and greater risk aversion (p<0.001). They reported less negative affect than controls (disappointment: p = 0.007; regret: p = 0.01), although their implicit emotional reactions as measured by post-choice SCRs did not differ. In the CGT, RRMS patients differed from controls in quality of DM (p = 0.01) and deliberation time (p = 0.0002), the latter difference being correlated with attention scores. Such changes did not result in overall decreases in performance (total gains).
  
  
  CONCLUSIONS
  The quality of DM under risk was modified by MS in both tasks. The reduction in the expression of disappointment coexisted with an increased risk aversion in the WOF and alexithymia features. These concomitant emotional alterations may have implications for better understanding the components of explicit DM and for the clinical support of MS patients.
authors.affiliation: Department of Clinical Neurosciences, University Hospital and University of Lausanne, Lausanne, Switzerland.
authors.forename: Samanta
authors.initials: S
authors.lastname: Simioni
authors.forename: Myriam
authors.initials: M
authors.lastname: Schluep
authors.forename: Nadège
authors.initials: N
authors.lastname: Bault
authors.forename: Giorgio
authors.initials: G
authors.lastname: Coricelli
authors.forename: Joerg
authors.initials: J
authors.lastname: Kleeberg
authors.forename: Renaud A
authors.initials: RA
authors.lastname: Du Pasquier
authors.forename: Markus
authors.initials: M
authors.lastname: Gschwind
authors.forename: Patrik
authors.initials: P
authors.lastname: Vuilleumier
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Annoni
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002755:Choice Behavior; D003071:Cognition / Q000502:physiology; D003657:Decision Making; D003710:Demography; D004644:Emotions / Q000502:physiology; D005260:Female; D005712:Galvanic Skin Response; D005715:Gambling / Q000523:psychology; D006801:Humans; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000503:physiopathology / Q000523:psychology*; D009483:Neuropsychological Tests; D012309:Risk-Taking; D013647:Task Performance and Analysis; D055815:Young Adult