Exoskeletal-Assisted Walking in Veterans With Paralysis: A Randomized Clinical Trial.

Importance: Robotic exoskeletons leverage technology that assists people with spinal cord injury (SCI) to walk. The efficacy of home and community exoskeletal use has not been studied in a randomized clinical trial (RCT). Objective: To examine whether use of a wheelchair plus an exoskeleton compared with use of only a wheelchair led to clinically meaningful net improvements in patient-reported outcomes for mental and physical health. Design, Setting, and Participants: This RCT of veterans with SCI was conducted at 15 Veterans Affairs medical centers in the US from September 6, 2016, to September 27, 2021. Data analysis was performed from March 10, 2022, to June 20, 2024. Interventions: Participants were randomized (1:1) to standard of care (SOC) wheelchair use or SOC plus at-will use of a US Food and Drug Administration (FDA)-cleared exoskeletal-assisted walking (EAW) device for 4 months in the home and community. Main Outcomes and Measures: Two primary outcomes were studied: 4.0-point or greater improvement in the mental component summary score on the Veterans RAND 36-Item Health Survey (MCS/VR-36) and 10% improvement in the total T score of the Spinal Cord Injury-Quality of Life (SCI-QOL) physical and medical health domain and reported as the proportion who achieved clinically meaningful changes. The primary outcomes were measured at baseline, post randomization after advanced EAW training sessions, and at 2 months and 4 months (primary end point) in the intervention period. Device usage, reasons for not using, and adverse events were collected. Results: A total of 161 veterans with SCI were randomized to the EAW (n = 78) or SOC (n = 83) group; 151 (94%) were male, the median age was 47 (IQR, 35-56) years, and median time since SCI was 7.3 (IQR, 0.5 to 46.5) years. The difference in proportion of successes between the EAW and SOC groups on the MCS/VR-36 (12 of 78 [15.4%] vs 14 of 83 [16.9%]; relative risk, 0.91; 95% CI, 0.45-1.85) and SCI-QOL physical and medical health domain (10 of 78 [12.8%] vs 11 of 83 [13.3%]; relative risk, 0.97; 95% CI, 0.44-2.15) was not statistically different. Device use was lower than expected (mean [SD] distance, 1.53 [0.02] miles per month), primarily due to the FDA-mandated companion being unavailable 43.9% of the time (177 of 403 instances). Two EAW-related foot fractures and 9 unrelated fractures (mostly during wheelchair transfers) were reported. Conclusions and Relevance: In this RCT of veterans with SCI, the lack of improved outcomes with EAW device use may have been related to the relatively low device usage. Solutions for companion requirements and user-friendly technological adaptations should be considered for improved personal use of these devices. Trial Registration: ClinicalTrials.gov Identifier: NCT02658656.

Evaluating the Use of Medicare Part D in the Veteran Population With Spinal Cord Injury/Disorder.

OBJECTIVE: To examine the different sources of medications, the most common drug classes filled, and the characteristics associated with Medicare Part D pharmacy use in veterans with spinal cord injury/disorder (SCI/D). DESIGN: Retrospective, cross-sectional, observational study. SETTING: Outpatient clinics and pharmacies. PARTICIPANTS: Veterans (N=13,442) with SCI/D using Medicare or Veteran Affairs pharmacy benefits. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Characteristics and top 10 most common drug classes were examined in veterans who (1) used VA pharmacies only; (2) used both VA and Medicare Part D pharmacies; or (3) used Part D pharmacies only. Chi-square tests and multinomial logistic regression analyses were used to determine associations between various patient variables and source of medications. Patient level frequencies were used to determine the most common drug classes. RESULTS: A total of 13,442 veterans with SCI/D were analyzed in this study: 11,788 (87.7%) used VA pharmacies only, 1281 (9.5%) used both VA and Part D pharmacies, and 373 (2.8%) used Part D pharmacies only. Veterans older than 50 years were more likely to use Part D pharmacies, whereas those with traumatic injury, or secondary conditions, were less associated with the use of Part D pharmacies. Opioids were the most frequently filled drug class across all groups. Other frequently used drug classes included skeletal muscle relaxants, gastric medications, antidepressants (other category), anticonvulsants, and antilipemics. CONCLUSIONS: Approximately 12% of veterans with SCI/D are receiving medication outside the VA system. Polypharmacy in this population of veterans is relatively high, emphasizing the importance of health information exchange between systems for improved care for this medically complex population.

Management learning from air purifier tests in hotels: Experiment and action research.

Recently, indoor air quality (IAQ) has become an important issue as it affects people's comfort and health. To mitigate the problem, application of some innovative air filtering devices has been generally recognized as one of the effective ways. This study adopted an action research-dominated approach to test whether the indoor air quality in the tested hotel rooms meets the recognized standard, and measure the pollutant removal efficiency of three types of air purifiers. Focus group discussion was carried out to ascertain the difference in hotel managers' understanding of indoor air quality research before the experiment and management response after the experiment. The result of field test indicates that the actual performance of the purifiers is not as good as the manufactures claim. The management response study also ascertains that hotel department heads' awareness, exposure and training in relation to IAQ testing is limited.

Not physically present contours can yield illusory motion.

We demonstrate a perceptual effect whereby contours not physically present in a visual scene can yield striking illusory motion. The not physically present contours are paths of invariant contrast polarity (CP). For example, when a square checkerboard composed of dark and light square checks with small black and white discs covering the vertices is put in lateral motion, there is the striking perception of vertical expansion/contraction. Such a checkerboard has (not physically present) diagonal paths of CP presentation with vertical components. However, when a square checkerboard made up of square black and very light checks with gray discs of luminance intermediate to the checks is put in lateral motion, no expansion/contraction is seen. For this checkerboard the vertical components of paths of CP preservation cancel each other out, predicting the lack of perception of vertical expansion/contraction. We also discuss how not physically present contours can explain previously described effects and suggest new effects to be explored.

Changing trends in the management of end-stage neuromuscular respiratory muscle failure: recommendations of an international consensus.

OBJECTIVE: Respiratory management of patients with end-stage respiratory muscle failure of neuromuscular disease has evolved from no treatment and inevitable respiratory failure to the use of up to continuous noninvasive intermittent positive pressure ventilatory support (CNVS) to avert respiratory failure and to permit the extubation of "unweanable" patients without tracheostomy. An international panel experienced in CNVS was charged by the 69th Congress of the Mexican Society of Pulmonologists and Thoracic Surgeons to analyze changing respiratory management trends and to make recommendations. DESIGN: Neuromuscular disease respiratory consensuses and reviews were identified from PubMed. Individual respiratory interventions were identified; their importance was established by assessing the quality of evidence-based literature for each one and their patterns of use over time. The panel then determined the evidence-based strength for the efficacy of each intervention and made recommendations for achieving prolonged survival by CNVS. RESULTS: Fifty publications since 1993 were identified. Continuous positive airway pressure, oxygen therapy, bilevel positive airway pressure used at both low and high spans, "air stacking," manually assisted coughing, low pressure (<35 cm H2O) and high pressure (≥40 cm H2O) mechanically assisted coughing, noninvasive positive pressure ventilation part time (<23 hrs per day) and full time (>23 hrs per day; CNVS), extubation and decannulation of ventilator-dependent patients to CNVS, and oximetry feedback for noninvasive positive pressure ventilation and mechanically assisted coughing were identified. All noted interventions are being used with increasing frequency and were unanimously recommended to achieve prolonged survival by CNVS, with the exception of supplemental oxygen and continuous positive airway pressure, which are being used less and were not recommended for this population. CONCLUSIONS: CNVS and extubation of unweanable patients to CNVS are increasingly being used to prolong life while avoiding invasive interfaces.

Contrast polarity preservation's role in perception: explained and unexplained stimuli.

Roncato and Casco (2003, Perception & psychophysics 65 1252-1272) had shown that in situations where the Gestalt principle of good continuity is put into conflict with preservation of contrast polarity (CP) the perception that preserves CP prevails. Parlangeli and Roncato (2010, Perception 39 255-259) have studied this question of preservation of CP more closely and have added an addendum to the rule. They have used stimuli consisting of a checkerboard of perpendicularly arranged rectangular bricks (white, gray, or black) and draughtsmen white, gray, or black disks placed at the corners of the bricks. This study has caused them to add an addendum to the rule of CP-preserved path-conjunction binding: if there are two contour completions that preserve the CP, the one with the higher contrast will prevail. Parlangeli and Roncato find that, for certain shades of the disks and bricks, the perpendicular lines of the checkerboard appear strikingly to be slanted or undulating. Here we consider all possible arrangements of relative magnitudes of checkerboards consisting of bricks of two different shades and disks of two shades as well, as such arrangements with widely varying differences in the magnitude of brightness. We have found a number of cases where the perception is not explained by the rule and addendum of Roncato and Casco, and Parlangeli and Roncato, and a case where preservation of "distant" as well as local CP plays a role in perception. The previously known cases, and the new exceptional unexplained stimuli we have found, warrant further study.

Noninvasive respiratory management for patients with spinal cord injury and neuromuscular disease.

The purpose of this article is to describe noninvasive respiratory management for patients with neuromuscular respiratory muscle dysfunction (NMD) and spinal cord injury (SCI) and the role of electrophrenic pacing (EPP) and diaphragm pacing (DP) in this respect. Long term outcomes will be reviewed and the use of noninvasive intermittent positive pressure ventilation (NIV), MAC, and EPP/DP to prevent pneumonia and acute respiratory failure, to facilitate extubation, and to avoid tracheotomy will be evaluated. Although ventilator dependent patients with most NMDs and high level SCI can be indefinitely managed noninvasively, most ALS patients can be managed for a limited time by continuous NIV before tracheostomy is necessary for survival. Glossopharyngeal breathing (GPB) can be learned by patients without any autonomous breathing ability and used by them in the event of ventilator/EPP/DP failure or loss of interface access. EPP/DP can maintain alveolar ventilation for high level SCI patients when they cannot grab a mouth piece to use NIV.

Koffka's effect is mediated by figure thickness at the joining region.

Three-quarters of a century ago Gestalt psychologist Kurt Koffka described a remarkable effect: when a contiguous gray ring is placed on a background half one shade of gray, half another, the ring appears homogeneous. However, if the ring is divided, the two halves of the ring appear different shades of gray, the half of the ring on the darker background appearing lighter than the half of the ring on the lighter background. The Gestalt principle of continuity is used to explain this effect. But what microscopic principles might be mediating this effect? Recently we found sufficiently thin rings (annuli) appear heterogeneous even when geometrically continuous. Here, using crescent-shaped figures instead of the circular annuli used for the traditional Koffka effect, we show that this effect of thickness of the ring is mediated by the thickness at the boundary of the region where the halves of the figure are joined.

Metameric intransitivity.

There are two kinds of afterimages. In negative afterimages, looking at a blank field after staring at a colored figure gives a figure whose color is complementary to that of the original figure. Less well understood and studied is the phenomenon of induced positive afterimages, in which staring at a colored area surrounding a small white test patch produces an afterimage in which the hue of the surround is transferred into the previously white area. Using these differences between positive and negative afterimages and also simultaneous color contrast, which has an effect on a test patch different from either of the afterimage effects, we describe a new effect, metameric intransitivity, in which perceptually similar images can generate markedly different afterimages, whereas perceptually different images can generate indistinguishable afterimages. Supplemental figures depicting the stimuli, results, and method for generating the intransitive metamers in this study may be downloaded from http://app.psychonomic-journals.org/content/supplemental.

The Wertheimer-Benary effect does not invert, and a nulled Wertheimer-Benary effect.

More than three-quarters of a century ago Wertheimer and Benary demonstrated an ingenious and clear, though, interestingly, small effect: a grey triangle just inside an arm of a black cross on a white background appears slightly lighter than an identical triangle immediately adjacent to the cross, despite both triangles having the same perimeter exposure to black and white. Over a generation ago White discovered an apparently related, but far stronger effect: when short grey (test) bars are placed onto either black or white alternating long bars, the short test bars placed on the long black bars appear much lighter than those placed on the long white bars. A decade ago Spehar, Gilchrist, and Arend found that, enigmatically, if the short test bars in White's effect are the lightest stimulus in a figure, then the relative lightness of the test bars inverts compared with the standard version of White's effect. Here we show that the Wertheimer-Benary effect does not invert, but instead produces a very weak version of the standard effect. We also demonstrate a novel, nulled Wertheimer-Benary effect.

Thickness and the Koffka ring effect.

Over seven decades ago Gestalt psychologist Kurt Koffka described a remarkable effect: when a contiguous gray ring is placed on a background half of one shade of gray, half of another, the ring appears homogeneous. However, if the ring is slightly divided, the two halves of the ring appear different shades of gray, the half of the ring on the darker background appearing lighter than the half of the ring on the lighter background. The Gestalt principle of continuity is used to explain this effect. We show that when the ring is made thinner it appears heterogeneous even when contiguous. We also illustrate this in the additional material with a colored background with more than two regions.