Functional Connectivity and Response Inhibition: A Secondary Analysis of an 8-Week Randomized Controlled Trial of Computerized Cognitive Training

Article type: Research Article

Authors: Ten Brinke, Lisanne F.^{a; b; c} | Hsu, Chun Liang^{a; b; c; d} | Erickson, Kirk I.^e | Handy, Todd C.^f | Liu-Ambrose, Teresa^{a; b; c; *}

Affiliations: [a] Aging, Mobility, and Cognitive Neuroscience Laboratory, Department of Physical Therapy, University of British Columbia, Vancouver, British Columbia, Canada | [b] Djavad Mowafaghian Centre for Brain Health, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Vancouver, British Columbia, Canada | [c] Centre for Hip Health and Mobility, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada | [d] Hinda and Arthur Marcus Institute for Aging Research, Hebrew Senior Life, Boston, MA, USA | [e] Department of Psychology, University of Pittsburgh, Pittsburgh, PA, USA | [f] Department of Psychology, University of British Columbia, Vancouver, BC, Canada

Correspondence: [*] Correspondence to: Teresa Liu-Ambrose, PhD, PT, Aging, Mobility, and Cognitive Neuroscience Laboratory, Department of Physical Therapy, Djavad Mowafaghian Centre for Brain Health, Vancouver Coastal Health Research Institute, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada. Tel.: 604 875 4111 ext. 69059; E-mail: [email protected];@UBC_CogMobLab.

Abstract: Background:Evidence suggests that computerized cognitive training (CCT) can improve cognitive function in older adults, particularly executive functions. However, the underlying mechanisms by which CCT may improve executive functions are not well established. Objective:To determine: 1) inter-network functional connectivity correlates of changes in executive functions; and 2) the effect of CCT on these functional connectivity correlates. Methods:This secondary analysis included a subset of 124 adults aged 65–85 years enrolled in an 8-week randomized controlled trial of CCT. Participants were randomized to either: 1) group-based CCT 3x/week for 1 hour plus 3x/week home-based training; 2) group-based CCT preceded by brisk walking (Ex+CCT) 3x/week for 1 hour plus 3x/week home-based training; or 3) group-based balanced and toned (BAT) classes 3x/week for 1 hour (control). At baseline and trial completion, 65 of the 124 participants completed resting-state functional magnetic resonance imaging and neuropsychological tests of executive functions, specifically the Stroop Colour-Word Test and Flanker Test. Results:Improved performance on the Stroop Colour-Word Test and Flanker Test were associated with decreased correlation between the default mode network (DMN) and the fronto-parietal network (FPN) (p < 0.05). Compared with BAT, CCT alone significantly decreased correlation between the left dorsolateral prefrontal cortex and both the left and right medial temporal gyrus (–0.143, 95%CI [–0.256,–0.030], p = 0.014, and –0.123, 95%CI [–0.242,–0.004], p = 0.043, respectively). Conclusion:Decreased correlation between DMN and FPN, indicating less connection between these networks, may be an underlying mechanism by which CCT improves executive functions. Future studies are needed to replicate this finding.

Keywords: Clinical trial, cognitive aging, executive function, magnetic resonance imaging

DOI: 10.3233/JAD-200844

Journal: Journal of Alzheimer's Disease, vol. 80, no. 4, pp. 1525-1537, 2021