Cognitive Correlates of Digital Clock Drawing Metrics in Older Adults with and without Mild Cognitive Impairment

Article type: Research Article

Authors: Dion, Catherine^a | Arias, Franchesca^b | Amini, Shawna^c | Davis, Randall^d | Penney, Dana^e | Libon, David J.^f | Price, Catherine C.^{a; c; *}

Affiliations: [a] Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA | [b] Aging Brain Center at Hebrew Senior Life, Harvard University, Boston, MA, USA | [c] Department of Anesthesiology, University of Florida, Gainesville, FL, USA | [d] Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA | [e] Department of Neurology, Lahey Clinic Medical Center, Burlington, MA, USA | [f] Department of Geriatrics, Gerontology, and Psychology, Rowan University, Glassboro, NJ, USA

Correspondence: [*] Correspondence to: Catherine C. Price, PhD, ABPP/CN, Associate Professor, Department of Clinical and Health Psychology, University of Florida, College of PHHP, P.O. Box 100165, Gainesville, FL 32605-6617, USA. Tel.: +1 352 273 5929; E-mail: [email protected].

Abstract: Background:A digital version of the clock drawing test (dCDT) provides new latency and graphomotor behavioral measurements. These variables have yet to be validated with external neuropsychological domains in non-demented adults. Objective:The current investigation reports on cognitive constructs associated with selected dCDT latency and graphomotor variables and compares performances between individuals with mild cognitive impairment (MCI) and non-MCI peers. Methods:202 non-demented older adults (age 68.79 ± 6.18, 46% female, education years 16.02 ± 2.70) completed the dCDT and a comprehensive neuropsychological protocol. dCDT variables of interest included: total completion time (TCT), pre-first hand latency (PFHL), post-clock face latency (PCFL), and clock face area (CFA). We also explored variables of percent time drawing (i.e., ‘ink time’) versus percent time not drawing (i.e., ‘think time’). Neuropsychological domains of interest included processing speed, working memory, language, and declarative memory. Results:Adjusting for age and premorbid cognitive reserve metrics, command TCT positively correlated with multiple cognitive domains; PFHL and PCFL negatively associated with worse performance on working memory and processing speed tests. For Copy, TCT, PCFL, and PFHL negatively correlated with processing speed, and CFA negatively correlated with language. Between-group analyses show MCI participants generated slower command TCT, produced smaller CFA, and required more command ‘think’ (% Think) than ‘ink’ (% Ink) time. Conclusion:Command dCDT variables of interest were primarily processing speed and working memory dependent. MCI participants showed dCDT differences relative to non-MCI peers, suggesting the dCDT may assist with classification. Results document cognitive construct validation to digital metrics of clock drawing.

Keywords: Attention, cognition, cognitive aging, neuropsychology, processing speed

DOI: 10.3233/JAD-191089

Journal: Journal of Alzheimer's Disease, vol. 75, no. 1, pp. 73-83, 2020