Prefrontal Cortex Activity during Dual Task Performance: A Functional Neuroimaging Study

Abstract

Event Abstract Back to Event Prefrontal Cortex Activity during Dual Task Performance: A Functional Neuroimaging Study Syed A. Hassan1*, Leandro V. Bonetti2, Kara K. Patterson3, Deryk S. Beal4, Anthony C. Ruocco5 and Darlene Reid3 1 University of Toronto, Rehabilitation Sciences Institute, Department of Physical Therapy, Canada 2 University of Caxias do Sul, Department of Physical Therapy, Brazil 3 University of Toronto, Department of Physical Therapy, Canada 4 University of Toronto, Department of Speech-Language Pathology, Canada 5 University of Toronto, Department of Psychology, Canada BACKGROUND. Chronic Obstructive Pulmonary Disease (COPD) is the fourth leading cause of death and had an associated healthcare burden of $50 billion USD in 2010 (Guarascio, Ray, Finch, & Self, 2013). Alterations in the prefrontal cortex (PFC), involved in attentional control, planning and decision making, may in part explain the cognitive impairment and motor deficits (e.g., impaired balance and slower walking speed) in COPD patients. Functional near infrared spectroscopy (fNIRS) is a novel imaging technique that can quantify cortical neural activity via oxy-hemoglobin (O2Hb) and provide insight into the link between central processing and motor performance. OBJECTIVE. To compare relative changes in the PFC O2Hb, accuracy of backwards spelling, and decrements in gait during single and dual tasks in patients with COPD, and healthy young and old adults. HYPOTHESES. H1: PFC O2Hb will increase during backwards spelling compared to the baseline task and increase even more during dual tasks compared to single tasks in patients with COPD, and healthy old and young adults. H2: Compared to single tasks, participants in all three groups will have a decrease in accuracy of backwards spelling and greater decrements in gait during dual tasks. METHODS. All participants performed the following single tasks: (1) backwards spelling as the cognitive task (CT); (2) 30m preferred paced walk (PPW); and (3) 30m fast paced walk (FPW). The dual tasks then paired CT with each of PPW and FPW. The fNIRS data was processed in fnirSoft to attenuate physiological noise (e.g. heart rate) and motion artifacts. Changes in the left dorsolateral PFC O2Hb were then calculated using the modified Beer-Lambert law. Gait parameters (e.g. velocity) were measured using a 5x0.88m pressure sensitive Zeno mat (contains 13,824 pressure sensors). RESULTS. Twenty young healthy adults (10M:10F) with a mean age of 28±4 years, twenty old healthy adults (10M:10F) with a mean age of 64±11 years and six adults with COPD (3M:3F) with a mean age of 74±8 years participated. The PFC ∆O2Hb increased during the CT compared to the baseline task in the healthy young individuals (p=0.042) and tended to be greater in healthy old adults and COPD patients. Similarly, it was significantly higher in the old adults during the FPW+CT compared to FPW (0.27±0.95µM vs. -0.49±1.01µM, p=0.007) as well as during PPW+CT compared to PPW (0.20±0.77µM vs. -0.35±0.84µM, p=0.019). In addition, PFC ∆O2Hb tended to be higher during FPW+CT compared to FPW in healthy young adults (-0.04±0.97µM vs. -0.36±1.09µM) and COPD patients (0.13±1.09µM vs. 0.07±0.85µM). When comparing single tasks to dual tasks, the accuracy of the backwards spelling decreased significantly in the young healthy (-16.9±21.4%, p=0.002) and old healthy group (-20.1±22.2%, p=0.001) and tended to decrease in the COPD group (-32.2±45.7%, p=0.191) during performance of FPW+CT compared to CT alone. Similarly, participants exhibited decrements in gait during dual tasks compared to single tasks: (1) velocity during FPW+CT decreased in all three groups compared to FPW alone (Figure 1); (2) velocity during PPW+CT decreased in older adults compared to PPW alone (Figure 1); (3) swing time variability also increased in old adults and COPD patients during FPW+CT compared to FPW alone (p=0.030 and p=0.038, respectively); and (4) stance time variability of COPD patients increased during FPW+CT compared to FPW (p=0.026) and of young and old healthy adults during PPW+CT compared to PPW (p=0.027 and p=0.015, respectively). CONCLUSIONS. Our results demonstrate that dual tasks compared to single tasks increased more PFC ∆O2Hb, decreased accuracy of spelling backwards and resulted in slower and more variable gait. A larger sample of COPD patients would refine the strength of our data. Figure 1 References Guarascio, A. J., Ray, S. M., Finch, C. K., & Self, T. H. (2013). The clinical and economic burden of chronic obstructive pulmonary disease in the USA. ClinicoEconomics and outcomes research: CEOR, 5, 235. Keywords: functional near infrared spectrosopy (fNIRS), Dual Task Performance, prefrontal cortex (PFC), Gait, Chronic obstructive pulmonary disease (COPD) Conference: 2nd International Neuroergonomics Conference, Philadelphia, PA, United States, 27 Jun - 29 Jun, 2018. Presentation Type: Oral Presentation Topic: Neuroergonomics Citation: Hassan SA, Bonetti LV, Patterson KK, Beal DS, Ruocco AC and Reid D (2019). Prefrontal Cortex Activity during Dual Task Performance: A Functional Neuroimaging Study. Conference Abstract: 2nd International Neuroergonomics Conference. doi: 10.3389/conf.fnhum.2018.227.00127 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 31 Mar 2018; Published Online: 27 Sep 2019. * Correspondence: Mr. Syed A Hassan, University of Toronto, Rehabilitation Sciences Institute, Department of Physical Therapy, Toronto, Canada, ahmeds.hassan@mail.utoronto.ca Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Syed A Hassan Leandro V Bonetti Kara K Patterson Deryk S Beal Anthony C Ruocco Darlene Reid Google Syed A Hassan Leandro V Bonetti Kara K Patterson Deryk S Beal Anthony C Ruocco Darlene Reid Google Scholar Syed A Hassan Leandro V Bonetti Kara K Patterson Deryk S Beal Anthony C Ruocco Darlene Reid PubMed Syed A Hassan Leandro V Bonetti Kara K Patterson Deryk S Beal Anthony C Ruocco Darlene Reid Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.