Remote concussion history does not affect visually-guided reaching in young adult females

Aim: We examined the long-term effects of concussions in young adult females on visuomotor behavior during a visually-guided reaching task of various complexities. Materials & methods: 20 females with a history of longer than 6 months since a concussion and 20 healthy females quickly and accurately performed a delayed reach to a previously cued target. Results: As both cognitive and motor load increased, task performance decreased for both groups (p \u3c 0.05). However, contrary to our primary hypothesis, no differences in task performance were found between the two experimental groups (p \u3e 0.05). Conclusion: The young adult females with a remote history of concussion demonstrated no deficits in visuomotor behavior on an attention-mediated reaching task as compared with control participants. Lay abstract: Current literature is inconclusive regarding the long-term effects of concussion. Some have argued that the differing results are due to many uncontrolled factors in study design. In this study, 20 females with a history of concussion more than 6 months ago and 20 healthy females performed a reaching task under different levels of difficulty. As the reaching task got harder, both groups had greater difficulty doing the task quickly and accurately (p \u3c 0.05). Surprisingly, however, no differences in reaching performance existed between the two groups (p \u3e 0.05). Young adult females with a remote history of concussion demonstrated no greater problems with complicated reaching tasks when compared with control participants when experimental conditions are tightly controlled

Effects of Cognition on Visual Attention and Gait in Older Adults

One in 3 adults over 65 years fall annually, resulting in costs of $34 billion in 2013. Our purpose was to investigate the effect of cognitive load on visual attention and subsequent gait quality in this population. We hypothesize that visual attention deficits, due to increased cognitive demands, impair gait in older adults. Fourteen healthy older adults (70-91 years) and 10 younger adults (18-28 years) performed three randomly assigned tasks including a modified Timed Up and Go (mTUG; participants stood up from a chair, walked 4.7 meters around a cone, and returned to a seated position); a cognitive task (subtracted 7s from a given number as quickly and accurately as possible), and these two tasks combined. If participants gazed less at critical visual cues (i.e., cone and chair) during the dual task than when walking alone, we would conclude that cognitive load negatively affected visual attention. We tracked eye movements (Mobile Eye-XG, ASL) to identify the focus of visuospatial attention, and recorded walking characteristics using a pressure-sensing mat (GAITRite). Dependent measures included cognitive performance (rate and accuracy of subtraction task), visuospatial attention (fixation time on targets), and gait parameters. Gait baselines between ages differed. However the ‘cost’ of cognitive load was similar between age groups. Stride length, velocity, and cadence decreased, while walk time and double stance time lengthened, with increased cognitive load. Gaze time on target was significantly different between tasks for younger adults, but not older adults. Our results suggest that deficits in visuospatial attention do not completely explain gait changes in older adults, although older adults with the poorest cognitive performance had the greatest impairments in walk times and visuospatial attention. Thus, fall prevention programs should consider addressing cognitive status to optimize effectiveness