Effects of Dual-Task Training on Cognitive and Motor Learning and Cortical Activation in Healthy Young Adults

The purpose of this study is to assess the influence of a dual-task (combined motor-cognitive task) on dual-task performance of a complex dynamic stability task in healthy young adults and to assess the effects of dual-task training on cognitive-motor learning and cortical activation in healthy young adults. A dual-task is defined as concurrent performance of two tasks, usually a cognitive and motor task, that can be performed independently and have distinct and separate goals. Individuals engage in dual tasks every day and must allocate attentional resources to each task. While recognition of susceptibility to performance decrements in dual-task settings may be difficult, increased dual-task complexity is associated with decreased performance in one or both tasks. The well documented effects of dual-task practice represent a promising approach to improve dual-task performance for clinical populations such as individuals with neurological conditions or older individuals, in which complex multitask situations can increase fall risk due to hindered balance and walking performance. Similarly, young adults have demonstrated performance decrements while executing a dual-task that involved a combined balance and cognitive task. Research of dual-task training in healthy young cohort has indicated significant improvements in both motor and cognitive task performance in dual-task situations, suggesting the efficiency of this intervention strategy. However, most of these studies have investigated effects of a simple postural task combined with cognitive task training on dual-task performance. Effects of dual-task training using a complex dynamic postural stability task on dual-task performance of such complex task is lacking. Moreover, existing studies demonstrate conflicting evidence of dual-task training effects among healthy young adults since improvements in the motor task only have been largely reported. It is crucial to understand dual-task training effects on performance of a complex cognitive-motor task since postural control involves complex integration of somatosensory, vestibular, and visual systems. Our experimental paradigm will challenge these systems; thus, findings of this study would inform our intervention strategies in a variety of populations ranging from athletes to individuals with neurological conditions.

Dynamic postural stability is an integral aspect of postural control and it involves complex interaction of prefrontal, somatosensory, vestibular, and visual systems. However, a motor task involving complex interaction of these systems combined with cognitive task challenges has not been investigated thoroughly. Moreover, neural activation within these cortical areas during dual-task performance and effects of dual-task training are largely unknown.

Since, coordinated control of the body requires integration of all these systems (i.e. prefrontal, somatosensory, vestibular, and visual), it is important to systemically study the interference of an additional attention-demanding task, such as an auditory stimulus reaction time task on interaction of these systems that may contribute to decreased postural stability. Moreover, it is important to investigate if training on such a complex dual-task can reduce motor-cognitive interference, improve postural stability, and optimize cortical activation in complex dual-task conditions.