title: Stress and gender effects on prefrontal cortex oxygenation levels assessed during single and dual-task walking conditions.
abstract: The ability to walk is critical for functional independence and wellbeing. The pre-frontal cortex (PFC) plays a key role in cognitive control of locomotion, notably under attention-demanding conditions. Factors that influence brain responses to cognitive demands of locomotion, however, are poorly understood. Herein, we evaluated the individual and combined effects of gender and perceived stress on stride velocity and PFC Oxygenated Hemoglobin (HbO2) assessed during single and dual-task walking conditions. The experimental paradigm included Normal Walk (NW); Cognitive Interference (Alpha); and Walk-While-Talk (WWT) tasks. An instrumented walkway was used to assess stride velocity in NW and WWT conditions. Functional Near-Infrared-Spectroscopy (fNIRS) was used to quantify PFC HbO2levels during NW, Alpha and WWT. Perceived task-related stress was evaluated with a single 11-point scale item. Participants were community residing older adults (age = 76.8 ± 6.7 years; %female = 56). Results revealed that higher perceived stress was associated with greater decline in stride velocity from single to dual-task conditions among men. Three-way interactions revealed that gender moderated the effect of perceived stress on changes in HbO2levels comparing WWT to NW and Alpha. Attenuation in the increase in HbO2levels, in high compared to low perceived stress levels, from the two single task conditions to WWT was observed only in men. Thus, older men may be more vulnerable to the effect of perceived stress on the change in PFC oxygenation levels across walking conditions that vary in terms of cognitive demands. These findings confer important implications for assessment and treatment of individuals at risk of mobility impairments.
authors.affiliation: Department of Neurology, 1225 Morris Park Avenue, Van Etten, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.|Ferkauf Graduate School of Psychology of Yeshiva University, Bronx, NY, USA.
authors.forename: Roee
authors.identifier: 0000-0001-6639-0724
authors.initials: R
authors.lastname: Holtzer
authors.affiliation: Ferkauf Graduate School of Psychology of Yeshiva University, Bronx, NY, USA.
authors.forename: Chelsea
authors.initials: C
authors.lastname: Schoen
authors.affiliation: Ferkauf Graduate School of Psychology of Yeshiva University, Bronx, NY, USA.
authors.forename: Eleni
authors.initials: E
authors.lastname: Demetriou
authors.affiliation: Department of Neurology, 1225 Morris Park Avenue, Van Etten, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
authors.forename: Jeannette R
authors.initials: JR
authors.lastname: Mahoney
authors.affiliation: Drexel University School of Biomedical Engineering, Philadelphia, PA, USA.
authors.forename: Meltem
authors.initials: M
authors.lastname: Izzetoglu
authors.affiliation: Department of Epidemiology, Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: Cuiling
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Neurology, 1225 Morris Park Avenue, Van Etten, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.|Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: Joe
authors.initials: J
authors.lastname: Verghese
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition; D005260:Female; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D010108:Oxyhemoglobins / Q000378:metabolism; D017397:Prefrontal Cortex / Q000098:blood supply / Q000378:metabolism / Q000502:physiology*; D012737:Sex Factors; D013312:Stress, Physiological; D016138:Walking / Q000502:physiology*
chemical_list: D010108:Oxyhemoglobins
keywords: executive functions; functional Near-Infrared Spectroscopy; locomotion; prefrontal cortex; stress