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Abstract Background Virtual and augmented reality (AR) have become popular modalities for training myoelectric prosthesis control with upper-limb amputees. While some systems have shown moderate success, it is unclear how well the complex motor skills learned in an AR simulation transfer to completing the same tasks in physical reality. Limb loading is a possible dimension of motor skill execution that is absent in current AR solutions that may help to increase skill transfer between the virtual and physical domains. Methods We implemented an immersive AR environment where individuals could operate a myoelectric virtual prosthesis to accomplish a variety of object relocation manipulations. Intact limb participants were separated into three groups, the load control (CGLD; $$N=4$$ N = 4 ), the AR control (CGAR; $$N=4$$ N = 4 ), and the experimental group (EG; $$N=4$$ N = 4 ). Both the CGAR and EG completed a 5-session prosthesis training protocol in AR while the CGLD performed simple muscle training. The EG attempted manipulations in AR while undergoing limb loading. The CGAR attempted the same manipulations without loading. All participants performed the same manipulations in physical reality while operating a real prosthesis pre- and post-training. The main outcome measure was the change in the number of manipulations completed during the physical reality assessments (i.e. completion rate). Secondary outcomes included movement kinematics and visuomotor behavior. Results The EG experienced a greater increase in completion rate post-training than both the CGAR and CGLD. This performance increase was accompanied by a shorter motor learning phase, the EG’s performance saturating in less sessions of AR training than the CGAR. Conclusion The results demonstrated that limb loading plays an important role in transferring complex motor skills learned in virtual spaces to their physical reality analogs. While participants who did not receive limb loading were able to receive some functional benefit from AR training, participants who received the loading experienced a greater positive change in motor performance with their performance saturating in fewer training sessions.

Changes in both swallowing and taste commonly occur in advanced age, though the relationship between the two is unknown. This study examined the association between a water swallow screen test and taste identification and intensity rating. Participants included 47 community-dwelling women aged 85⁻94 years. Participants completed three trials of a water swallow screen and were observed for signs of aspiration, which, if present, indicated failure. Four pure taste stimuli at low and high concentrations and water were presented, and participants selected one of five taste labels and rated their intensity on the generalized Labeled Magnitude Scale. Ratios of intensity ratings were computed for each taste stimulus to compare the perception of low and high concentrations. The association between water swallow screen failure, correct taste identification, and taste intensity ratio was evaluated with logistic regression modeling, with mediating factors of frailty and number of comorbidities. Failure of three water swallow screen trials was associated with a higher taste intensity ratio for caffeine (bitter) and a lower taste intensity ratio for sucrose (sweet). Correct identification of taste, frailty, and number of comorbidities were not associated with failure of any number of water swallow screen trials. Intensity ratings of certain tastes may be associated with swallowing in old-old women. Heightened vigilance in this population may be necessary to prevent complications related to dietary intake.

Abstract Background Kidney disease and dialysis significantly impact cognitive function across the age spectrum. Cognitive training (CT) and/or exercise training (ET) are promising approaches to preserve cognitive function among community-dwelling older adults, but have not been tested for cognition preservation in hemodialysis patients of all ages. In this manuscript, we summarize the protocol for the Interventions Made to Preserve Cognitive Function Trial (IMPCT). Methods We will perform a 2 × 2 factorial randomized controlled trial (RCT) of eligible adult (≥18 years) hemodialysis initiates (n = 200) to test whether intradialytic CT (brain games on a tablet PC), ET (foot peddlers) and combined CT + ET while undergoing hemodialysis preserves executive function compared to standard of care (SC). Participants will engage in the interventions to which they are randomized for 6 months. The primary objective is to compare, among interventions, the 3-month change in executive function measured using the Trail Making Test A (TMTA) and B (TMTB); specifically, executive function is calculated as TMTB-TMTA to account for psychomotor speed. This primary outcome was selected based on findings from our pilot study. The secondary objectives are to compare the risk of secondary cognitive outcomes, ESKD-specific clinical outcomes, and patient-centered outcomes at 3-months and 6-months. All data collection and interventions are conducted in the dialysis center. Discussion We hypothesize that receiving intradialytic CT or ET will better preserve executive function than SC but receiving combined CT + ET, will be the most effective intervention. The current trial will be an important step in understanding how intradialytic interventions might preserve cognitive health. Trial Registration Clinicaltrials.Gov (Date: 8/6/18): # NCT03616535 . Protocol Version: 10 (April 2020). Funding: NIDDK R01DK114074.

Abstract Background Few objective tests can be performed at admission for kidney transplantation [KT] to discern risk of increased length of stay [LOS], which is important for patient counseling and is associated with increased costs and mortality. The short physical performance battery [SPPB] is an easily administered, potentially modifiable, 3-part test of lower extremity function. SPPB score is associated with longer hospital LOS in older adults, and may provide similar utility in KT recipients given that ESRD is a disease of accelerated aging. The aim of this study was to characterize the association between SPPB-derived lower extremity function and LOS. Methods The SPPB was administered at KT admission in a prospective cohort of 595 recipients (8/2009–6/2016). The independent association between SPPB impairment (score ≤ 10) and LOS was tested with an adjusted conventional generalized gamma parametric survival model. Results Impaired recipients experienced longer LOS (median: 10 vs. 8 days; P

Cognitive decline is common and increases mortality risk in hemodialysis patients. Intradialytic interventions like cognitive training (CT) and exercise training (ET) may preserve cognitive function. Methods: We conducted a pilot randomized controlled trial of 20 hemodialysis patients to study the impact of 3 months of intradialytic CT (tablet-based brain games) (n = 7), ET (foot peddlers) (n = 6), or standard of care (SC) (n = 7) on cognitive function. Global cognitive function was measured by the Modified Mini Mental Status Exam (3MS), psychomotor speed was measured by Trail Making Tests A and B (TMTA and TMTB), and executive function was assessed by subtracting (TMTB − TMTA). Lower 3MS scores and slower TMTA and TMTB times reflected worse cognitive function. P values for differences were generated using analysis of variance, and 95% confidence intervals (CIs) and P values were generated from linear regression. Results: Patients with SC experienced a decrease in psychomotor speed and executive function by 3 months (TMTA: 15 seconds; P = 0.055; TMTB: 47.4 seconds; P = 0.006; TMTB − TMTA; 31.7 seconds; P = 0.052); this decline was not seen among those with CT or ET (all P > 0.05). Compared with SC, the difference in the mean change in 3MS score was −3.29 points (95% CI: −11.70 to 5.12; P = 0.42) for CT and 4.48 points (95% CI: −4.27 to 13.22; P = 0.30) for ET. Compared with SC, the difference in mean change for TMTA was −15.13 seconds (95% CI: −37.64 to 7.39; P = 0.17) for CT and −17.48 seconds (95% CI: −41.18 to 6.22; P = 0.14) for ET, for TMTB, the difference was −46.72 seconds (95% CI: −91.12 to −2.31; P = 0.04) for CT and −56.21 seconds (95% CI: −105.86 to −6.56; P = 0.03) for ET, and for TMTB – TMTA, the difference was −30.88 seconds (95% CI: −76.05 to 14.28; P = 0.16) for CT and −34.93 seconds (95% CI: −85.43 to 15.56; P = 0.16) for ET. Conclusion: Preliminary findings of our pilot study suggested that cognitive decline in psychomotor speed and executive function is possibly prevented by intradialytic CT and ET. These preliminary pilot findings should be replicated.