Behavioral regulation: factor analysis and application of the Behavioral Dyscontrol Scale in dementia and mild cognitive impairment

Abstract

Executive dysfunction is a hallmark of both Dementia of the Alzheimer's Type (AD) and Vascular Dementia (VaD). A complete neuropsychological battery contains measures of executive function, but the focus tends to be on cognitive processes with verbal or written output. The Behavioral Dyscontrol Scale (BDS) is purported to be a measure of executive function that addresses control over voluntary motor behavior. Previous factor analyses revealed three-factor solutions using a variety of patient populations. Our goals were to examine the factor structure in a sample of geriatric outpatients and to apply that factor structure to detect possible differences between AD, VaD, amnestic Mild Cognitive Impairment (MCI), non-amnestic MCI, and normal controls. An exploratory factor analysis was performed on 260 outpatient evaluations from 2002-2006. Only the seven items requiring motor responses were included. A two-factor solution emerged. We named the factors Motor Problem-Solving and Simple Motor Repetitive Behaviors. For the first factor, the AD and VaD groups differed from the MCI groups and normal controls, but did not differ from each other. There were no differences between the control, amnestic MCI, and non-amnestic MCI groups. There were no differences between the groups for the second factor. It was concluded that voluntary control of behavior that requires problem-solving for complex tasks may help differentiate dementia from mild cognitive impairment and normal aging.