Myotonic Dystrophy type 1 and Duchenne Muscular Dystrophy: cognitive profile and behavioral functioning

Abstract

Duchenne muscular dystrophy (DMD) and myotonic dystrophy type 1 (DM1) are two neuromuscular disorders with a proven correlation between neurological deficits and cognitive deficits. These children have a high prevalence of learning disorders, reading problems in particular, which seems to be caused by deficits in verbal working memory and/or visuospatial functioning. Also a deviating behavior profile with internalizing and attention problems is seen in these children. The aim of the present study was (1) to describe the verbal working memory and visuospatial functioning, and reading skills and behavioral functions of children with DMD and DM1, (2) compare them with normative data and (3) compare DMD and DM1 patients with children with learning disabilities without a evident neurological comorbidity. Three children with myotonic dystrophy type 1 and four children with Duchenne muscular dystrophy in the range of 3 to 11 had undergone a neuropsychological assessment, behaviour questionnaires were completed by the parents. Deviating visuospatial functions were found in DMD and DM1 patients, when comparing them with normative data. With respect to their behavioural profile, DMD patients had more externalising problems compared to the normative data and to children with Verbal Learning Disorders. The data of this study did not correspond with previous studies on DMD and DM1. Limitations and implications for future research are discussed.