title: On the importance of cognitive profiling: A graphical modelling analysis of domain-specific and domain-general deficits after stroke.
abstract: Cognitive problems following stroke are typically analysed using either short but relatively uninformative general tests or through detailed but time consuming tests of domain specific deficits (e.g., in language, memory, praxis). Here we present an analysis of neuropsychological deficits detected using a screen designed to fall between other screens by being 'broad' (testing multiple cognitive abilities) but 'shallow' (sampling the abilities briefly, to be time efficient) - the BCoS. Assessment using the Birmingham Cognitive Screen (BCoS) enables the relations between 'domain specific' and 'domain general' cognitive deficits to be evaluated as the test generates an overall cognitive profile for individual patients. We analysed data from 287 patients tested at a sub-acute stage of stroke (<3 months). Graphical modelling techniques were used to investigate the associative structure and conditional independence between deficits within and across the domains sampled by BCoS (attention and executive functions, language, memory, praxis and number processing). The patterns of deficit within each domain conformed to existing cognitive models. However, these within-domain patterns underwent substantial change when the whole dataset was modelled, indicating that domain-specific deficits can only be understood in relation to linked changes in domain-general processes. The data point to the importance of using over-arching cognitive screens, measuring domain-general as well as domain-specific processes, in order to account for neuropsychological deficits after stroke. The paper also highlights the utility of using graphical modelling to understand the relations between cognitive components in complex datasets.
authors.affiliation: Department of Statistics, Oxford University, Oxford, UK.
authors.forename: M Sofia
authors.initials: MS
authors.lastname: Massa
authors.affiliation: Department of Statistics, Oxford University, Oxford, UK.
authors.forename: Naxian
authors.initials: N
authors.lastname: Wang
authors.affiliation: School of Psychology, University of Birmingham, Birmingham, UK.
authors.forename: Wa-Ling
authors.initials: WL
authors.lastname: Bickerton
authors.affiliation: Department of Experimental Psychology, Oxford University, Oxford, UK.
authors.forename: Nele
authors.initials: N
authors.lastname: Demeyere
authors.affiliation: Department of Experimental Psychology, Oxford University, Oxford, UK.
authors.forename: M Jane
authors.initials: MJ
authors.lastname: Riddoch
authors.affiliation: Department of Experimental Psychology, Oxford University, Oxford, UK. Electronic address: glyn.humphreys@psy.ox.ac.uk.
authors.forename: Glyn W
authors.initials: GW
authors.lastname: Humphreys
mesh_terms: D000368:Aged; D001288:Attention; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology* / Q000523:psychology*; D016208:Databases, Factual; D056344:Executive Function; D005260:Female; D006801:Humans; D007807:Language Tests; D008297:Male; D008433:Mathematics; D008568:Memory; D008875:Middle Aged; D008959:Models, Neurological; D009483:Neuropsychological Tests; D011597:Psychomotor Performance; D020521:Stroke / Q000150:complications* / Q000523:psychology*
keywords: Assessment; Cognitive impairment; Statistical analysis