title: Executive dysfunction predicts social cognition impairment in amyotrophic lateral sclerosis.
abstract: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder of the motor system with recognised extra-motor and cognitive involvement. This cross-sectional study examined ALS patients' performance on measures requiring social inference, and determined the relationship between such changes and variations in mood, behaviour, personality, empathy and executive function. Fifty-five ALS patients and 49 healthy controls were compared on tasks measuring social cognition and executive function. ALS patients also completed measures examining mood, behaviour and personality. Regression analyses explored the contribution of executive function, mood, behaviour and personality to social cognition scores within the ALS sample. A between-group MANOVA revealed that, the ALS group was impaired relative to controls on two composite scores for social cognition and executive function. Patients also performed worse on individual tests of executive function measuring cognitive flexibility, response inhibition and concept formation, and on individual aspects of social cognition assessing the attribution of emotional and mental states. Regression analyses indicated that ALS-related executive dysfunction was the main predictor of social cognition performance, above and beyond demographic variables, behaviour, mood and personality. On at least some aspects of social cognition, impaired performance in ALS appears to be secondary to executive dysfunction. The profile of cognitive impairment in ALS supports a cognitive continuum between ALS and frontotemporal dementia.
authors.affiliation: Department of Psychology, Bangor University, Bangor, UK.
authors.forename: Tamlyn J
authors.initials: TJ
authors.lastname: Watermeyer
authors.forename: Richard G
authors.initials: RG
authors.lastname: Brown
authors.forename: Katie C L
authors.initials: KC
authors.lastname: Sidle
authors.forename: David J
authors.initials: DJ
authors.lastname: Oliver
authors.forename: Christopher
authors.initials: C
authors.lastname: Allen
authors.forename: Joanna
authors.initials: J
authors.lastname: Karlsson
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Ellis
authors.forename: Christopher E
authors.initials: CE
authors.lastname: Shaw
authors.forename: Ammar
authors.initials: A
authors.lastname: Al-Chalabi
authors.forename: Laura H
authors.initials: LH
authors.lastname: Goldstein
mesh_terms: D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000150:complications*; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology*; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012919:Social Behavior; D018709:Statistics, Nonparametric