Dual and Triple Cognitive-Motor Task Interventions in Old Adults

Introduction

Multitasking is common in many everyday situations. Walking while overcoming obstacles, driving a car while paying attention to traffic signs and watching television while maintaining short conversations are all examples of the simultaneous performance of two tasks in daily life. Multitasking affects different areas of life and can involve combinations of social, physical and psychological aspects of daily functioning (McIsaac, Lamberg and Muratori (2015). Dual tasking (DT), the most common multitasking condition, consists of combining two different single tasks at same time. In order to differentiate DT from performance of a complex single task, DT must meet two general characteristics: (1) each task can be performed and measured separately; and (2) the tasks each have different goals (McIsaac et al., 2015).

In the last decade, DT has become an important line of research in the study of age-related changes in psychogerontology. DT research can differentiate patterns of performance in old and young adults, and it can also help to identify potential age-related risk situations and disabilities. For example, DT performance is a marker of incident dementia in Mild Cognitive Impairment (MCI) (Montero-Odasso et al., 2017) and cognitive frailty (Navarro-Pardo et al., 2020); it can also be useful to differentiate healthy participants from those with late-life depression, MCI (Naidu et al., 2019) or an increased risk of falling (Beauchet et al., 2008; Kim & Yoo, 2020; Verghese et al., 2002), and it can also indicate different degrees of disability in Parkinson’s Disease (Pereiro et al., 2020).

Executive function (EF) is one of the most vulnerable cognitive functions in the process of ageing and is affected by age-related changes in the frontal lobe (Beurskens & Bock, 2012). In psychogerontology, the concurrent-task paradigm (multitask setting) has been used to assess executive attention, specifically to assess the ability to share attentional resources in order to follow the requirements of two or more tasks. In this context, walking is the task most commonly combined with another in DT situations in the study of age-related changes. Gait is related to EF in normal walking (without a secondary task), mainly in dual tasking conditions (van Iersel et al., 2008).

In the methodology used to study multitasking, three different alternative DT pairings are considered: motor-cognitive, motor-motor and cognitive-cognitive. The motor-cognitive combination has been the most commonly used in recent studies. This combination includes gait tasks as the most widely used motor task, but other tasks have been used, for example, static cycling (Lorenzo-López et al., 2020; Takeuchi et al., 2020) and static standing (Gillain et al., 2009). Regarding the combinations of cognitive tasks, more heterogeneous and diverse alternatives are used in research: memory, fluency, counting down (by 7 and by 3), response to auditory stimuli (Fallahtafti et al., 2020), listening to and answering questions (Jeon et al., 2015) and reciting letters of the alphabet (Tripathi et al., 2018), among many others. The combination of a gait task and a cognitive task that involves providing a verbal response is a very popular motor-cognitive combination proposed by Verghese et al. (2002), as the walking-while-talking test. This test is considered an appropriate choice for assessing functional performance, as a very common task in daily life.