A Single Dermatome Clinical Prediction Rule for Independent Walking 1 Year After Spinal Cord Injury.

OBJECTIVE: To derive and validate a simple, accurate CPR to predict future independent walking ability after SCI at the bedside that does not rely on motor scores and is predictive for those initially classified in the middle of the SCI severity spectrum. DESIGN: Retrospective cohort study. Binary variables were derived, indicating degrees of sensation to evaluate predictive value of pinprick and light touch variables across dermatomes. The optimal single sensory modality and dermatome was used to derive our CPR, which was validated on an independent dataset. SETTING: Analysis of SCI Model Systems dataset. PARTICIPANTS: Individuals with traumatic SCI. The data of 3679 participants (N=3679) were included with 623 participants comprising the derivation dataset and 3056 comprising the validation dataset. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Self-reported ability to walk both indoors and outdoors. RESULTS: Pinprick testing at S1 over lateral heels, within 31 days of SCI, accurately identified future independent walkers 1 year after SCI. Normal pinprick in both lateral heels provided good prognosis, any pinprick sensation in either lateral heel provided fair prognosis, and no sensation provided poor prognosis. This CPR performed satisfactorily in the middle SCI severity subgroup. CONCLUSIONS: In this large multi-site study, we derived and validated a simple, accurate CPR using only pinprick sensory testing at lateral heels that predicts future independent walking after SCI.

Predictive modeling of ambulatory outcomes after spinal cord injury using machine learning.

STUDY DESIGN: Retrospective multi-site cohort study. OBJECTIVES: To develop an accurate machine learning predictive model using predictor variables from the acute rehabilitation period to determine ambulatory status in spinal cord injury (SCI) one year post injury. SETTING: Model SCI System (SCIMS) database between January 2000 and May 2019. METHODS: Retrospective cohort study using data that were previously collected as part of the SCI Model System (SCIMS) database. A total of 4523 patients were analyzed comparing traditional models (van Middendorp and Hicks) compared to machine learning algorithms including Elastic Net Penalized Logistic Regression (ENPLR), Gradient Boosted Machine (GBM), and Artificial Neural Networks (ANN). RESULTS: Compared with GBM and ANN, ENPLR was determined to be the preferred model based on predictive accuracy metrics, calibration, and variable selection. The primary metric to judge discrimination was the area under the receiver operating characteristic curve (AUC). When compared to the van Middendorp all patients (0.916), ASIA A and D (0.951) and ASIA B and C (0.775) and Hicks all patients (0.89), ASIA A and D (0.934) and ASIA B and C (0.775), ENPLR demonstrated improved AUC for all patients (0.931), ASIA A and D (0.965) ASIA B and C (0.803). CONCLUSIONS: Utilizing artificial intelligence and machine learning methods are feasible for accurately classifying outcomes in SCI and may provide improved sensitivity in identifying which individuals are less likely to ambulate and may benefit from augmentative strategies, such as neuromodulation. Future directions should include the use of additional variables to further refine these models.

Predicting Outdoor Walking 1 Year After Spinal Cord Injury: A Retrospective, Multisite External Validation Study.

BACKGROUND AND PURPOSE: Predicting future outdoor walking ability after spinal cord injury (SCI) is important, as this is associated with community engagement and social participation. A clinical prediction rule (CPR) was derived for predicting outdoor walking 1 year after SCI. While promising, this CPR has not been validated, which is necessary to establish its clinical value. The objective of this study was to externally validate the CPR using a multisite dataset. METHODS: This was a retrospective analysis of US SCI Model Systems data from 12 centers. L3 motor score, L5 motor score, and S1 sensory score were used as predictor variables. The dataset was split into testing and training datasets. The testing dataset was used as a holdout dataset to provide an unbiased estimate of prediction performance. The training dataset was used to determine the optimal CPR threshold through a "leave-one-site-out" cross-validation framework. The primary outcome was self-reported outdoor walking ability 1 year after SCI. RESULTS: A total of 3721 participants' data were included. Using the optimal CPR threshold (CPR ≥ 33 threshold value), we were able to predict outdoor walking 1 year with high cross-validated accuracy and prediction performance. For the entire dataset, area under receiver operator characteristic curve was 0.900 (95% confidence interval: 0.890-0.910; P < 0.0001). DISCUSSION AND CONCLUSIONS: The outdoor walking CPR has been externally validated. Future research should conduct a clinical outcomes and cost-benefit impact analysis for implementing this CPR. Our results support that clinicians may use this 3-variable CPR for prediction of future outdoor walking ability.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A411 ).

Venous Thromboembolism: Exploring Incidence and Utility of Screening in Individuals With Brain Injury.

OBJECTIVE: To determine the incidence of VTE in the population with brain injuries (BIs) using ultrasonography, and to assess the risk of pulmonary embolism (PE) development and/or bleeding complications related to anticoagulation. DESIGN: Retrospective study. SETTING: Acute rehabilitation hospital. PARTICIPANTS: 238 individuals with moderate to severe BI who were routinely screened for VTE with ultrasonography on admission to rehabilitation (N=238). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Retrospective chart review was performed to identify individuals who were diagnosed with VTE at the following 3 time points: in acute care prior to admission to rehabilitation, at the time of admission diagnosed via screening examination, and after admission to rehabilitation. Additionally, risk factors for VTE, PE, and incidence of bleeding complications related to therapeutic anticoagulation were assessed. RESULTS: 123 deep vein thromboses (DVTs) were identified with 38.2% in acute care (n=47), 69.1% on admission to rehabilitation (n=85), and 7.3% during the course of rehabilitation stay (n=9). Risk factors for development of VTE included age at injury, body mass index, injury etiology, history of neurosurgical procedure, and surgery during inpatient rehabilitation. Of those who were placed on therapeutic anticoagulation due to admission diagnosis of VTE (n=50), 2% developed recurrent DVT and 2% had bleeding complications. There was zero incidence of PE. CONCLUSION: We demonstrated a high prevalence of VTEs identified on screening ultrasonography on admission to inpatient rehabilitation among individuals with moderate to severe BIs, and low complications related to anticoagulation. Given the findings of this study, prospective research in ultrasonography screening for VTE in moderate to severe BI is needed.

Changes in essential care in individuals with spinal cord injury during the COVID-19 pandemic.

STUDY DESIGN: Cross-sectional, observational study. OBJECTIVES: To determine whether changes in essential care during the COVID-19 pandemic impacted satisfaction with activities, participation, and relationships among individuals with spinal cord injury (SCI). SETTING: Data were collected online between December 31, 2020 and February 14, 2021 among community dwelling adults with SCI (N = 123). METHODS: The primary outcome variables were satisfaction with the ability to complete activities of daily living (ADLs) (mobility, dressing, feeding, and toileting), as well as satisfaction with participation in household and recreational activities, and satisfaction with relationships among friends, family, and with the status of one's relationship measured with the International Spinal Cord Injury Data Sets Activities and Participation Basic Data Set. Primary predictors were age, gender, time since injury, completeness of injury, injury level, access to mental health, access to medications, access to medical supplies, and access to personal care assistants (PCAs). RESULTS: Impact on access to mental health and impact on access to supplies were the most common factors affecting satisfaction with activities, participation, and relationships for individuals with SCI during the COVID-19 pandemic. Impact on access to PCAs/homecare was also found to impact certain outcomes including feeding and participation in household activities. CONCLUSIONS: Future supply chain disruptions from pandemics or natural disasters could have wide-reaching effects for individuals with SCIs. Thus, further research and advocacy is needed to improve mental health care planning and supply chain access during subsequent natural disasters.

Long-Term Follow-Up of Patients With Ventilator-Dependent High Tetraplegia Managed With Diaphragmatic Pacing Systems.

OBJECTIVE: To explore participants' experiences after implantation of a diaphragmatic pacing system (DPS). DESIGN: Cross-sectional, observational study using self-report questionnaires. SETTING: Participants were recruited from 6 Spinal Cord Injury Model System centers across the United States (Craig Hospital, CO; Jefferson/Magee Rehabilitation Hospital, PA; Kessler Rehabilitation Center, NJ; University of Miami, FL; The Shirly Ryan Ability Lab, IL; Shepherd Center, GA). INTERVENTIONS: Not applicable. PARTICIPANTS: Men and women (N=28) with tetraplegia were enrolled in the study between November 2012 and January 2015. MAIN OUTCOME MEASURES: Participants completed self-report questionnaires focused on their DPS usage and mechanical ventilation, as well as their experiences and satisfaction with the DPS. RESULTS: DPS is a well-tolerated and highly successful device to help individuals living with spinal cord injury who are dependent on ventilators achieve negative pressure, ventilator-free breathing. A small percentage of participants reported complications, including broken pacing wires and surgery to replace or reposition wires. CONCLUSIONS: This study provides insight into the usage patterns of DPS and both the potential negative and positive effects that DPS can have on the life of the user. Knowledge gained from this study can provide a foundation for further discussion about the benefits and potential risks of using a DPS to inform an individual's decision to pursue a DPS implant.

Resilience and mental health in individuals with spinal cord injury during the COVID-19 pandemic.

STUDY DESIGN: Cross-sectional, observational study. OBJECTIVES: To understand how resilience, access to personal care attendants (PCAs) and medical supplies, and concerns about medical rationing, finances, and social isolation are related to overall and mental health in individuals with spinal cord injury (SCI) in the context of the COVID-19 pandemic. SETTING: Community dwelling adults (N = 187) with SCI. METHODS: Data were collected online between May 1, 2020 and August 31, 2020. Outcomes were overall and mental health, depression and anxiety symptoms, and quality of life (QoL). Predictors were resilience, access to PCAs and medical supplies, and concerns about medical rationing, finances, and social isolation. RESULTS: Incomplete injury, concern about medical rationing, medical supply disruption, and social isolation predicted a greater perceived impact of the pandemic on overall heath. Younger age, decreased resilience, and concern about medical rationing and social isolation predicted greater perceived impact of the pandemic on mental health. Decreased resilience and concern about medical rationing and finances predicted increased anxiety symptoms. Incomplete injury, believing that medical rationing was occurring, decreased resilience, and concern about finances and social isolation predicted increased depressive symptoms. Decreased resilience and concern about finances, medical rationing, and social isolation predicted lower QoL. CONCLUSIONS: The negative effects of the pandemic on the overall and mental health of individuals with SCI may be ameliorated by resilience. In future crises, it may be beneficial to screen individuals for resilience so that those with decreased resilience are offered the appropriate resources to enhance resilience and improve overall wellbeing.

Axial MRI biomarkers of spinal cord damage to predict future walking and motor function: a retrospective study.

STUDY DESIGN: Retrospective. OBJECTIVES: Primary: to assess if axial damage ratios are predictors of future walking after spinal cord injury (SCI), and if they add any predictive value if initial neurological impairment grades are available. Secondary: to determine if lateral spinal cord regions are predictors of future lower extremity motor scores (LEMS). SETTING: University/hospital. METHODS: Axial T2-weighted MRIs were used. Axial damage ratios and non-damaged lateral cord volumes were calculated. Each participant answered at 1 year after SCI, "Are you able to walk for 150 feet? (45.72 meters)" For the secondary aim, right and left LEMS were used. RESULTS: In total, 145 participants were selected. Individuals that could walk had smaller ratios than those that were unable. Walking and axial damage ratios were negatively correlated. A 0.374 ratio cut-off showed optimal sensitivity/specificity. When initial neurological grades were used, axial damage ratios did not add predictive value. Forty-two participants had LEMS available and were included for the secondary aim. Right cord regions and right LEMS were positively correlated and left regions and left LEMS, but these variables were also correlated with each other. CONCLUSIONS: Axial damage ratios were significant predictors of walking ability 1 year after SCI. However, this measure did not add predictive value over initial neurological grades. Lateral cord regions correlated with same-side LEMS, but the opposite was also found, calling this biomarker's specificity into question. Axial damage ratios may be useful in predicting walking after SCI if initial neurological grades are unavailable. SPONSORSHIP: This research was funded by a National Institutes of Health award, National Institute of Child Health and Development-NIH R03HD094577.

Perceived injustice after spinal cord injury: evidence for a distinct psychological construct.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: To identify unique predictors of perceived injustice compared with depression symptoms within the first year after SCI. SETTING: Inpatient rehabilitation program in a large urban region in the Southwestern United States. METHODS: A sample of 74 participants with median time since injury of 52 days completed measures of perceived injustice, depression symptoms, posttraumatic stress symptoms, expected disability, pain intensity, and anger. RESULTS: Three unique predictors of perceived injustice as compared with depression symptoms were found-time since injury, state anger, and sex. These predictors had significantly different relationships with perceived injustice than with depression symptoms. CONCLUSIONS: Results replicate previous findings that perceived injustice is moderately correlated with depression symptoms. However, findings also reveal factors uniquely associated with perceived injustice than with depression symptoms, providing support that these are two separate constructs. Thus, these findings support development of novel interventions targeting perceptions of injustice.

Disrupted sleep predicts next day agitation following moderate to severe brain injury.

Objective: Disrupted sleep is common during acute recovery from traumatic brain injury (TBI) and has been linked to daytime agitation. This study investigated the relationship among nighttime sleep efficiency (SE), total sleep time (TST), wakefulness after sleep onset (WASO), and number of wake bouts (NWB) as measured by actigraphy to observer ratings of agitation for patients with TBI who were undergoing inpatient rehabilitation. Methods: This is a retrospective, observational study of a convenience sample of 65 individuals admitted to TBI inpatient rehabilitation who were monitored with actigraphy and the Agitated Behaviour Scale (ABS) for the first 72 h. Each patient's average SE, TST, WASO, and NWB for the 72-h period was calculated using actigraphy for the rest interval from 2100 to 0700. Daily ABS scores were obtained for each day following the nighttime sleep period. Results: Patients were not significantly different on age, gender, etiology of injury, days post-injury, rehabilitation length of stay, or severity of injury as measured by length of posttraumatic amnesia (PTA). SE and TST were significantly lower for patients with agitation than for patients without agitation. Conclusions: This study suggests a relationship between disrupted sleep and agitation for patients with TBI who are undergoing inpatient rehabilitation.

Prognostic value of tissue bridges in cervical spinal cord injury: a longitudinal, multicentre, retrospective cohort study.

BACKGROUND: The accuracy of prognostication in patients with cervical spinal cord injury (SCI) needs to be improved. We aimed to explore the prognostic value of preserved spinal tissue bridges-injury-spared neural tissue adjacent to the lesion-for prediction of sensorimotor recovery in a large, multicentre cohort of people with SCI. METHODS: For this longitudinal study, we included patients with acute cervical SCI (vertebrae C1-C7) admitted to one of three trauma or rehabilitation centres: Murnau, Germany (March 18, 2010-March 1, 2021); Zurich, Switzerland (May 12, 2002-March 2, 2019); and Denver, CO, USA (Jan 12, 2010-Feb 16, 2017). Patients were clinically assessed at admission (baseline), at discharge (3 months), and at 12 months post SCI. Midsagittal tissue bridges were quantified from T2-weighted images assessed at 3-4 weeks post SCI. Fractional regression and unbiased recursive partitioning models, adjusted for age, sex, centre, and neurological level of injury, were used to assess associations between tissue bridge width and baseline-adjusted total motor score, pinprick score, and light touch scores at 3 months and 12 months. Patients were stratified into subgroups according to whether they showed better or worse predicted recovery. FINDINGS: The cohort included 227 patients: 93 patients from Murnau (22 [24%] female); 43 patients from Zurich (four [9%] female); and 91 patients from Denver (14 [15%] female). 136 of these participants (from Murnau and Zurich) were followed up for up to 12 months. At 3 months, per preserved 1 mm of tissue bridge at baseline, patients recovered a mean of 9·3% (SD 0·9) of maximal total motor score (95% CI 7·5-11.2), 8·6% (0·8) of maximal pinprick score (7·0-10·1), and 10·9% (0·8) of maximal light touch score (9·4-12·5). At 12 months post SCI, per preserved 1 mm of tissue bridge at baseline, patients recovered a mean of 10·9% (1·3) of maximal total motor score (8·4-13·4), 5·7% (1·3) of maximal pinprick score (3·3-8·2), and 6·9% (1·4) of maximal light touch score (4·1-9·7). Partitioning models identified a tissue bridge cutoff width of 2·0 mm to be indicative of higher or lower 3-month total motor, pinprick, and light touch scores, and a cutoff of 4·0 mm to be indicative of higher and lower 12-month scores. Compared with models that contained clinical predictors only, models additionally including tissue bridges had significantly improved prediction accuracy across all three centres. INTERPRETATION: Tissue bridges, measured in the first few weeks after SCI, are associated with short-term and long-term clinical improvement. Thus, tissue bridges could potentially be used to guide rehabilitation decision making and to stratify patients into more homogeneous subgroups of recovery in regenerative and neuroprotective clinical trials. FUNDING: Wings for Life, International Foundation for Research in Paraplegia, EU project Horizon 2020 (NISCI grant), and ERA-NET NEURON.

Venous thromboembolism: Exploring incidence and utility of screening in spinal cord injury.

OBJECTIVE: To assess the incidence and possible risk factors for venous thromboembolism (VTE) in patients admitted to a SCI rehabilitation center. DESIGN: Retrospective review. SETTING: Acute neurorehabilitation hospital specializing in SCI. METHODS: Records of 228 consecutive admissions were reviewed. All patients received screening four limb ultrasounds on admission. Charts were reviewed to determine whether VTE was diagnosed at the acute care hospital or in the rehabilitation center; either on admission screening or later in the rehabilitation stay. Charts were reviewed to identify potential risk factors for VTE as well as the incidence of bleeding complications in patients on full anticoagulation. RESULTS: In this cohort, 115 deep venous thromboses (DVTs) were identified in the following settings: 27% in acute care [n = 31], 70% on admission to rehabilitation [n = 80], and 24% during the rehabilitation stay [n = 28]. Of those on therapeutic anticoagulation due to admission diagnosis of VTE [n = 63], 12.7% developed recurrent DVT and 9.5% had bleeding complications. Of those who were initiated and continued on therapeutic anticoagulation, there was zero incidence of PE. Risk factors for the development of VTE included age, body mass index (BMI), rehabilitation length of stay, injury etiology, spinal cord-related surgery, and history of inferior vena cava filter. CONCLUSIONS: DVT was identified in 70% of this cohort with screening ultrasound on admission to rehabilitation and of those initiated and continued on therapeutic anticoagulation, none developed PE, while 9.5% had bleeding complications. Given the findings of this study, prospective research in noninvasive vascular ultrasound screening for VTE should be considered.

The impact of a structured rehabilitation program for uninsured individuals.

PURPOSE/OBJECTIVE: Health disparities in rehabilitation have been identified in brain injury (BI), spinal cord injury (SCI), stroke, and amputee populations. A free clinic was established to serve such uninsured individuals. The purpose of this exploratory study was to characterize the sample of patients attending a free rehabilitation clinic by investigating their demographics, access to care, trends in quality of life, and satisfaction with the rehabilitation program. METHOD/DESIGN: This is a retrospective chart review of data from 15 individuals admitted to the free clinic program who were administered an admission questionnaire, the abbreviated World Health Organization Quality of Life assessment (WHOQOL-BREF), and a postcare assessment survey. RESULTS: A majority of patients reported not having a primary care provider nor a checkup within the past 5 years. This sample also reported extensive physical needs at admission. Seventy-three percent of the sample improved on the WHOQOL-BREF physical domain by discharge with a large effect size. The psychological, social, and environmental domain scores did not show a reliable pattern of change in this sample. Conclusions/Implication: These results support previously noted gaps in care among individuals with BI, SCI, stroke, and amputation and suggest that a monthly clinic can improve physical quality of life. This exploratory study aims to lay the foundation for future research that is needed to understand the factors that exclude these individuals from the health care system and to help key stakeholders to advocate for these patients and improve their early access to rehabilitation care. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Fibrocartilagenous embolism case series: is it a zebra?

INTRODUCTION: There have been 30 clinically suspected cases and 41 histopathologically confirmed cases of fibrocartilaginous embolism (FCE) reported in the literature. FCE often has a poor prognosis and is estimated to represent 5.5% of spinal cord infarctions, but may be more common than initially presumed given underdiagnosis due to its vague clinical presentation. CASE PRESENTATION: We report two cases, a 15-year-old male and a 15-year-old female, whose clinical history, examination, and imaging findings were consistent with spinal cord infarction secondary to FCE. DISCUSSION: These cases were unique given our patients' neurologic improvement; however, the commonly held assumption of poor prognosis may in part be fueled by the preferential case ascertainment via biopsy on autopsy. These cases highlight the importance of recognizing rare causes of spinal cord pathology and considering FCE in the differential diagnosis of acute myelopathy.

Inpatient Rehabilitation After COVID-19 Hospitalization in a Patient With Lung Transplant: A Case Study.

ABSTRACT: Severe acute respiratory syndrome coronavirus 2, also known as coronavirus 2019 (COVID-19), has impacted the lives of many older individuals, with those with comorbidities having the highest risk of severe disease. Specifically, immunosuppression and chronic obstructive pulmonary disease are two important risk factors. This case report describes the rehabilitation course of a 62-yr-old woman with a history of a double lung transplant for chronic obstructive pulmonary disease in 2016 who contracted a severe COVID-19 infection. After nearly a month in the intensive care unit, she underwent a 10-day course of inpatient rehabilitation and regained substantial independence and was able to return home only needing supervision. Although other cases in the rehabilitation literature have documented successful rehabilitation after COVID-19 infection, this transplant-related case required intensive coordination of care to meet goals and achieve success for the patient. Because of the limited numbers of studies, this information may prove valuable in future considerations for candidates of inpatient rehabilitation.

The impact of stigma on psychosocial outcomes following spinal cord injury: A cross-sectional analysis of stigma-mediated relationships.

Purpose/Objective: The purpose of this study was to (a) assess the relationship between stigma and psychosocial outcomes and (b) examine the potential mediating influence of stigma on the relationship between sociodemographic and injury-related characteristics and psychosocial outcomes after spinal cord injury (SCI). Research Method/Design: This cross-sectional, observational study included participants enrolled in the Rocky Mountain Regional Spinal Cord Injury Model System. Questionnaires were administered via telephone. Stigma was assessed using the Spinal Cord Injury Quality of Life Stigma Short Form. Results: Questionnaires were completed by 225 participants (78% male; 22% female). Stigma was significantly, positively associated with depression symptoms, perceived disability, injustice appraisals, and participation (physical independence and mobility). Stigma was significantly, negatively associated with quality of life and self-efficacy. Stigma partially mediated several relationships between sociodemographic or injury-related characteristics and psychosocial outcomes. Stigma fully mediated the relationships between each time since injury and self-efficacy, length of rehabilitation stay and injustice appraisals, wheelchair use and self-efficacy, and wheelchair type and quality of life. Conclusions/Implication: Stigma is an important psychological factor associated with several person- and injury-related characteristics and psychosocial outcomes. Furthermore, stigma mediates particular relationships between sociodemographic or injury-related characteristics and outcomes. These findings will inform the development of interventions designed to mitigate stigma's negative impact on outcomes such as mood, quality of life, and participation after SCI. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

A qualitative exploration of perceived injustice among individuals living with spinal cord injury.

PURPOSE/OBJECTIVE: The purpose of the present qualitative study was to explore how people living with spinal cord injury (SCI) conceptualize 2 factors believed to contribute to perceptions of injustice (i.e., severity/irreparability of loss and blame/sense of unfairness) and identify specific sources that contribute to these perceptions. Research Method/Design: To assess perceived injustice, the 12-item Injustice Experience Questionnaire (IEQ) was administered via telephone to individuals enrolled in the National Spinal Cord Injury Statistical Center database who were 1 or 5 years postinjury. Participants then took part in individual, semistructured interviews exploring their experiences of perceived injustice following SCI. Four items from the IEQ formed the basis of the interviews. Two items representing each aforementioned factor of the IEQ were chosen. Qualitative data from 15 participants were subjected to content analysis to identify common themes. RESULTS: In response to items related to blame/unfairness, participants spoke about who and/or what was responsible for their injury, and these sources fell into 2 categories: fate or circumstance and internalized blame. In response to items related to severity/irreparability of loss, the predominant themes that emerged were life with disability, lack of understanding by others, and focus on the positive. CONCLUSIONS/IMPLICATIONS: The present study contributes a level of richness and depth to current conceptualizations of perceived injustice. Findings suggest that for individuals living with SCI, perceived injustice may be less related to fault and blame but instead more closely related to a lack of understanding of the injury. Further quantitative research is needed to elucidate these relationships. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Placebo sleep affects cognitive functioning.

The placebo effect is any outcome that is not attributed to a specific treatment but rather to an individual's mindset (Benson & Friedman, 1996). This phenomenon can extend beyond its typical use in pharmaceutical drugs to involve aspects of everyday life, such as the effect of sleep on cognitive functioning. In 2 studies examining whether perceived sleep quality affects cognitive functioning, 164 participants reported their previous night's sleep quality. They were then randomly assigned to 1 of 2 sleep quality conditions or 2 control conditions. Those in the "above average" sleep quality condition were informed that they had spent 28.7% of their total sleep time in REM, whereas those in the "below average" sleep quality condition were informed that they had only spent 16.2% of their time in REM sleep. Assigned sleep quality but not self-reported sleep quality significantly predicted participants' scores on the Paced Auditory Serial Addition Test and Controlled Oral Word Association Task. Assigned sleep quality did not predict participants' scores on the Digit Span task, as expected, nor did it predict scores on the Symbol Digit Modalities Test, which was unexpected. The control conditions showed that the findings were not due to demand characteristics from the experimental protocol. These findings supported the hypothesis that mindset can influence cognitive states in both positive and negative directions, suggesting a means of controlling one's health and cognition.