Although "cognition" and "movement" are commonly used terms by clinicians and researchers, they each actually represent quite complex abilities. Physical therapists are readily aware of the different aspects of movement (eg, strength, dexterity, balance), as well as different contexts in which movement occurs (eg, dual-task conditions, real-world), but may not be as familiar with the complexities of cognition that influence function. As this Special Issue shows, the ability to move effectively in daily life and to relearn and adapt movements following neurologic injury or disease relies extensively on multiple cognitive domains. Awareness and assessment of different domains of cognition have the potential to broaden the understanding of specific motor impairments, as well as the potential to tailor therapy and rehabilitation goals that better accommodate cognitive limitations. The domain of attention has been a focus in physical therapy for more than 20 years, with many studies of divided attention tasks during walking; however, there are other important aspects of cognition emerging for therapists to consider. For example, French et al showed how fluid cognition, which considers executive functions, processing speed, and attention in the context of problem-solving, may influence the ability to switch between trained walking patterns. This paper makes us consider cognition from a different perspective and challenges us to think about cognitive assessment and management beyond dual-tasking.
Some widely used measures, like the Mini-Mental Status Exam (MMSE), are used to quickly screen global cognition by cursorily evaluating attention, language, memory, and visuospatial/executive functions. Although global screening tools are relatively quick and easy to administer, they do not necessarily provide a detailed assessment of specific cognitive domains and could miss subtleties in cognition that affect function. As was the case in Flugon et al, a global measure like the MMSE did not show a significant relationship to motor and psychosocial factors. This cannot be interpreted to mean that specific cognitive domains like language, memory, or visuospatial/executive functions are unimportant for the neurorehabilitation process. We may be in need of better measures to capture specific cognitive impairments. Results from this Special Issue will encourage clinicians and researchers to learn more about various domains of cognition, be observant of possible impairments, and, if appropriate, directly assess those domains. We acknowledge, however, that cognitive assessment presents some challenges. First, some cognitive tests that are used for research purposes (including some presented in this Special Issue) may be too cost- or time-prohibitive for clinical use by physical therapists or other members of the health care team. Second, identifying which domains are critical to assess can be difficult. Because our speech-language pathologist or occupational therapist colleagues often take the lead in detailed cognitive testing, seeking their advice may be a simple way to identify which cognitive domain(s) is most important to consider in the provision of care, without the need to spend physical therapy time doing such testing. We view the consideration of cognition as an important factor in the field of neurologic physical therapy. We need to continue thinking collectively about the importance of domain-specific cognition and the value of adapting cognitive measures from research studies to use in the clinic. Furthermore, there may be specific portions of clinical motor measures (eg, the Timed Up and Go Cognitive, or the Dual-Task portion of the MiniBEST) that clinicians could use to gain insights into cognitive problems in patients in lieu of extensive cognitive testing.
Evaluating patients under dual-task conditions has tremendous benefit, not only as a "sneak peek" into their level of cognitive processing but also as a more real-world assessment of their motor ability. However, titrating the right combination of motor and cognitive challenges is important. Here, Rice et al showed how cognitive-motor interference may increase with more complex gait assessments. Furthermore, considering which task (the cognitive vs the motor task) an individual is prioritizing is critical, as prioritization may be highly individualized and/or context-specific. For example, for more cognitively impaired individuals, Gaillardin et al showed that the dual-task cost associated with stair descent was higher than with stair ascent. These 2 papers highlight the potential "value-added" of using dual-task conditions to gain insights into both cognitive and motor impairments limiting function.
Although the papers presented here illustrate how cognitive deficits might interfere with physical rehabilitation, this Special Issue also emphasizes how people with cognitive impairments can still engage in and benefit from physical therapy services. In fact, cognitively impaired individuals may arguably have an even greater need for services than cognitively intact individuals due to problems with attention, visuospatial ability, memory, or fluid cognition that limit problem-solving and motor learning on their own. For example, Gomes et al showed that cognitive deficits (ie, difficulty learning new verbal information, poor working memory and processing speed) negatively affected both physical therapy session attendance and rehabilitation goal attainment. The paper by Spiteri et al is especially encouraging, by showing that meaningful engagement and participation in physical therapy are feasible even in spite of significant cognitive impairments. The coexistence of cognitive and motor impairments in patients in neurologic practice is, in part, what draws many to this specialty. The treating therapist is faced with their own "cognitive challenge" to solve the puzzle before them and devise approaches that work best to improve the motor function of the individual seeking care. It is through research in areas represented in this Special Issue that we address these challenges and seek opportunities to improve physical therapy care.