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OBJECTIVE: This study aims to explore the factors associated with rheumatology providers' perceptions of telehealth utility in real-world telehealth encounters. METHODS: From September 14, 2020 to January 31, 2021, 6 providers at an academic medical center rated their telehealth visits according to perceived utility in making treatment decisions using the following Telehealth Utility Score (TUS) (1 = very low utility to 5 = very high utility). Modified Poisson regression models were used to assess the association between TUS scores and encounter diagnoses, disease activity measures, and immunomodulatory therapy changes during the encounter. RESULTS: A total of 481 telehealth encounters were examined, of which 191 (39.7%) were rated as "low telehealth utility" (TUS 1-3) and 290 (60.3%) were rated as "high telehealth utility" (TUS 4-5). Encounters with a diagnosis of inflammatory arthritis were significantly less likely to be rated as high telehealth utility (adjusted relative risk [aRR], 0.8061; p = 0.004), especially in those with a concurrent noninflammatory musculoskeletal diagnosis (aRR, 0.54; p = 0.006). Other factors significantly associated with low telehealth utility included higher disease activity according to current and prior RAPID3 scores (aRR, 0.87 and aRR, 0.89, respectively; p < 0.001) and provider global scores (aRR, 0.83; p < 0.001), as well as an increase in immunomodulatory therapy (aRR, 0.70; p = 0.015). CONCLUSIONS: Provider perceptions of telehealth utility in real-world encounters are significantly associated with patient diagnoses, current and prior disease activity, and the need for changes in immunomodulatory therapy. These findings inform efforts to optimize the appropriate utilization of telehealth in rheumatology.
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Artrite , Reumatologia , Telemedicina , Humanos , Pacientes Ambulatoriais , Centros Médicos AcadêmicosRESUMO
OBJECTIVE: We aimed to develop a decision-making tool to predict telehealth appropriateness for future rheumatology visits and expand telehealth care access. METHODS: The model was developed using the Encounter Appropriateness Score for You (EASY) and electronic health record data at a single academic rheumatology practice from January 1, 2021, to December 31, 2021. The EASY model is a logistic regression model that includes encounter characteristics, patient sociodemographic and clinical characteristics, and provider characteristics. The goal of pilot implementation was to determine if model recommendations align with provider preferences and influence telehealth scheduling. Four providers were presented with future encounters that the model identified as candidates for a change in encounter modality (true changes), along with an equal number of artificial (false) recommendations. Providers and patients could accept or reject proposed changes. RESULTS: The model performs well, with an area under the curve from 0.831 to 0.855 in 21,679 encounters across multiple validation sets. Covariates that contributed most to model performance were provider preference for and frequency of telehealth encounters. Other significant contributors included encounter characteristics (current scheduled encounter modality) and patient factors (age, Routine Assessment of Patient Index Data 3 scores, diagnoses, and medications). The pilot included 201 encounters. Providers were more likely to agree with true versus artificial recommendations (Cohen's κ = 0.45, P < 0.001), and the model increased the number of appropriate telehealth visits. CONCLUSION: The EASY model accurately identifies future visits that are appropriate for telehealth. This tool can support shared decision-making between patients and providers in deciding the most appropriate follow-up encounter modality.
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Reumatologia , Telemedicina , Humanos , PandemiasRESUMO
Background Nonalcoholic fatty liver disease (NAFLD) and heart failure with preserved ejection fraction (HFpEF) share common risk factors, including obesity and diabetes. They are also thought to be mechanistically linked. The aim of this study was to define serum metabolites associated with HFpEF in a cohort of patients with biopsy-proven NAFLD to identify common mechanisms. Methods and Results We performed a retrospective, single-center study of 89 adult patients with biopsy-proven NAFLD who had transthoracic echocardiography performed for any indication. Metabolomic analysis was performed on serum using ultrahigh performance liquid and gas chromatography/tandem mass spectrometry. HFpEF was defined as ejection fraction >50% plus at least 1 echocardiographic feature of HFpEF (diastolic dysfunction, abnormal left atrial size) and at least 1 heart failure sign or symptom. We performed generalized linear models to evaluate associations between individual metabolites, NAFLD, and HFpEF. Thirty-seven out of 89 (41.6%) patients met criteria for HFpEF. A total of 1151 metabolites were detected; 656 were analyzed after exclusion of unnamed metabolites and those with >30% missing values. Fifty-three metabolites were associated with the presence of HFpEF with unadjusted P value <0.05; none met statistical significance after adjustment for multiple comparisons. The majority (39/53, 73.6%) were lipid metabolites, and levels were generally increased. Two cysteine metabolites (cysteine s-sulfate and s-methylcysteine) were present at significantly lower levels in patients with HFpEF. Conclusions We identified serum metabolites associated with HFpEF in patients with biopsy-proven NAFLD, with increased levels of multiple lipid metabolites. Lipid metabolism could be an important pathway linking HFpEF to NAFLD.
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Insuficiência Cardíaca , Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Volume Sistólico , Estudos Retrospectivos , Cisteína , Lipídeos , BiópsiaRESUMO
Idiopathic myointimal hyperplasia of the mesenteric veins (IMHMV) is a rare cause of chronic colonic ischemia characterized by intimal smooth muscle proliferation and luminal narrowing of the small to medium sized mesenteric veins. It predominantly affects the rectosigmoid colon in otherwise healthy, middle-aged males. Definitive diagnosis and treatment are surgical; however, patients are frequently misdiagnosed, which often results in a protracted clinical course. We describe a case of IMHMV presenting as left hemicolitis in a 53-year-old male, as well as the endoscopic, histopathologic, and radiographic findings that established the diagnosis.
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Colite Isquêmica , Doenças Inflamatórias Intestinais , Masculino , Pessoa de Meia-Idade , Humanos , Hiperplasia/patologia , Veias Mesentéricas/cirurgia , Colite Isquêmica/etiologia , Colite Isquêmica/patologia , Colite Isquêmica/cirurgia , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/patologiaRESUMO
OBJECTIVE: The purpose of this study was to evaluate a novel scoring system, the Encounter Appropriateness Score for You (EASY), to assess provider perceptions of telehealth appropriateness in rheumatology encounters. METHODS: The EASY scoring system prompts providers to rate their own encounters as follows: in-person or telehealth acceptable, EASY = 1; in-person preferred, EASY = 2; or telehealth preferred, EASY = 3. Assessment of the EASY scoring system occurred at a single academic institution from January 1, 2021, to August 31, 2021. Data were collected in three rounds: 1) initial survey (31 providers) assessing EASY responsiveness to five hypothetical scenarios, 2) follow-up survey (34 providers) exploring EASY responsiveness to 11 scenario modifications, and 3) assessment of EASYs documented in clinic care. RESULTS: The initial and follow-up surveys demonstrated responsiveness of EASYs to different clinical and nonclinical factors. For instance, less than 20% of providers accepted telehealth when starting a biologic for active rheumatoid arthritis, although more than 35% accepted telehealth in the same scenario if the patient lived far away or was well known to the provider. Regarding EASY documentation, 27 providers provided EASYs for 12,381 encounters. According to these scores, telehealth was acceptable or preferred for 29.7% of all encounters, including 21.4% of in-person encounters. Conversely, 24.4% of telehealth encounters were scored as in-person preferred. CONCLUSION: EASY is simple, understandable, and responsive to changes in the clinical scenario. We have successfully accumulated 12,381 EASYs that can be studied in future work to better understand telehealth utility and optimize telehealth triage.
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Background: End-stage liver disease (ESLD) is associated with high morbidity and mortality, with liver transplantation as the only existing cure. Despite reduced quality of life and limited life expectancy, referral to palliative care (PC) rarely occurs. Moreover, there is scarcity of data on the appropriate timing and type of PC intervention needed. Aim: To evaluate PC utilization and documentation in ESLD patients declined or delisted for transplant at a tertiary care medical center with a large liver transplantation program. Methods: We performed a retrospective cohort study of all patients discussed in Liver Transplant Committee (LTC) at our academic medical center between August 2018 and May 2020 in the United States. Patients declined or delisted for liver transplantation were included. Baseline demographics, model for end-stage liver disease (MELD) score, decompensation events, and reason for transplant ineligibility were recorded. The primary outcome was PC referral. Secondary outcomes included survival from LTC decision, time from LTC decision to PC referral, and code status in relation to PC referral. Results: Of 769 patients discussed at LTC, 135 were declined for transplantation. Thirty-seven (27%) received referral to PC. When adjusting for body mass index and age, MELD score of 21-30 had odds ratio (OR) of 4.5 (95% confidence interval [CI]: 1.7-12.3) and MELD score >30 had OR of 12.8 (95% CI: 3.9-47.7) for PC referral when compared with MELD score <20. When adjusting for MELD score, presence of ascites had OR of 4.6 (95% CI: 1.1-19.1) and presence of multiple complications had OR of 2.2 (95% CI: 2.2-3.8). Conclusions: Only 37 (27%) patients delisted or declined for liver transplantation were referred to PC. MELD score and degree of decompensation were important factors associated with referral. Continued exploration of these data could help guide future studies and help determine timing and criteria for PC referral.
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Doença Hepática Terminal , Transplante de Fígado , Doença Hepática Terminal/cirurgia , Humanos , Cuidados Paliativos , Qualidade de Vida , Encaminhamento e Consulta , Estudos Retrospectivos , Índice de Gravidade de Doença , Estados UnidosRESUMO
OBJECTIVE: Limited health literacy and numeracy are associated with worse patient-reported outcomes and higher disease activity in systemic lupus erythematosus (SLE), but which factors may mediate this association is unknown. We sought to determine the association of health literacy and numeracy with SLE knowledge. METHODS: Patients with SLE were recruited from an academic center clinic. Participants completed validated assessments of health literacy (Newest Vital Sign [NVS]; n = 96) and numeracy (Numeracy Understanding in Medicine Instrument, Short Version [S-NUMI]; n = 85). They also completed the Lupus Knowledge Assessment Test (LKAT), which consists of 4 questions assessing SLE knowledge that were determined through consensus expert opinion for their wide applicability and importance related to self-management of the disease. Descriptive statistics and multivariable logistic regression modeling were used to analyze the results. RESULTS: In our SLE cohort (n = 125), 33% (32/96) had limited health literacy and 76% (65/85) had limited numeracy. The majority correctly identified that hydroxychloroquine prevented SLE flares (91%); however, only 23% of participants correctly answered a numeracy question assessing which urine protein to creatinine (UPC) ratio was > 1000 mg/g. The mean LKAT score was 2.7 out of 4.0. Limited health literacy, but not numeracy, was associated with lower knowledge about SLE as measured by the LKAT, even after adjusting for education. CONCLUSION: Patients with SLE with limited health literacy had lower knowledge about SLE. The LKAT could be further refined and/or used as a screening tool to identify patients with knowledge gaps. Further work is needed to improve patients' understanding of proteinuria and investigate whether literacy-sensitive education can improve care.
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Letramento em Saúde , Lúpus Eritematoso Sistêmico , Estudos de Coortes , Letramento em Saúde/métodos , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Programas de RastreamentoRESUMO
Identifying patients at higher risk for poor outcomes from nonalcoholic fatty liver disease (NAFLD) remains challenging. Metabolomics, the comprehensive measurement of small molecules in biological samples, has the potential to reveal novel noninvasive biomarkers. The aim of this study was to determine if serum metabolite profiles in patients with NAFLD associate with future liver-related events. We performed a retrospective single-center cohort study of 187 participants with biopsy-proven NAFLD. Metabolomic analysis was performed on serum using ultrahigh performance liquid chromatography/tandem mass spectrometry and gas chromatography/mass spectrometry. We identified liver-related events (variceal bleeding, ascites, spontaneous bacterial peritonitis, hepatic encephalopathy, hepatocellular carcinoma, hepatopulmonary or hepatorenal syndrome) by manual chart review between index biopsy (2007-2013) and April 1, 2018. Generalized linear models and Cox proportional hazards models were used to test the association of metabolites with liver-related events and time to first liver-related event, controlling for covariates and fibrosis stage. Over a mean ± SD follow-up of 6.9 ± 3.2 years, 11 participants experienced 22 liver-related events. Generalized linear models revealed 53 metabolites significantly associated with liver-related events (P < 0.05). In Cox proportional hazards modeling, 69 metabolites were significantly associated with time to future liver-related events (P < 0.05), seven of which met the false discovery rate threshold of 0.10: vitamin E metabolites gamma-carboxyethyl-hydroxychroman (gamma-CEHC) and gamma-CEHC glucuronide; primary bile acid metabolite taurochenodeoxycholate; serotonin metabolite 5-hydroxyindoleacetate; and lipid metabolites (i) 2-hydroxyglutarate, (ii) 3beta,17beta-diol disulfate 1, and (iii) eicosenoyl sphingomyelin. Conclusion: Metabolites of a primary bile acid, vitamin E, and serotonin were associated with future liver-related events. Our results suggest metabolite pathways may be useful for predicting which patients with NAFLD are at higher risk for hepatic decompensation.
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Ácidos e Sais Biliares/sangue , Hepatopatia Gordurosa não Alcoólica/sangue , Serotonina/sangue , Vitamina E/sangue , Adulto , Biomarcadores/sangue , Feminino , Seguimentos , Humanos , Modelos Lineares , Masculino , Metabolômica , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de RiscoRESUMO
BACKGROUND: High anti-Müllerian hormone (AMH) levels and 25-hydroxyvitamin D [25(OH)D] deficiency have been associated with polycystic ovarian syndrome (PCOS) in adult women, and implicated in its pathogenesis. Herein we determined if the level of both AMH and 25(OH)D are altered in adolescent females with clinical features of PCOS. METHODS: This is a cross-sectional study utilizing a retrospective chart review of 128 patients aged 12-20 referred to an academic adolescent gynecology and endocrinology clinic for an evaluation of suspected PCOS. Unadjusted comparisons of AMH and 25(OH)D distributions between subjects with and without PCOS were performed using the Wilcoxon Rank Sum test. Quantile regression was used to compare the median AMH and 25(OH)D between subject groups; adjusting for race, ethnicity, BMI, insurance type, age, and season when bloodwork was performed. RESULTS: Seventy-four subjects were classified as having PCOS by meeting ≥2 of the three Rotterdam diagnostic criteria, and 47 subjects met only one Rotterdam diagnostic criteria, and were used as the comparative non-PCOS group. There were statistically significant unadjusted differences in median levels of AMH and 25(OH)D. In the adjusted analyses, median AMH was significantly higher in the PCOS group compared to the non-PCOS group (+ 2.39 ng/mL, 95% CI 0.43, 4.35, p = 0.018); 25(OH)D was significantly lower in the PCOS group (- 9.01 ng/mL, 95% CI -14.49, - 3.53 p = 0.001). In our sample, adolescents in both groups had insufficient 25(OH)D level (22 ng/mL) and elevated BMI (32.2 kg/m2). CONCLUSIONS: Adolescents with PCOS display high levels of AMH and low 25(OH)D levels. Since traditional clinical markers of PCOS may be physiologic in adolescents, AMH and 25(OH)D may be used as surrogate markers of PCOS risk in adolescents.
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Hormônio Antimülleriano/sangue , Síndrome do Ovário Policístico/sangue , Vitamina D/análogos & derivados , Adolescente , Feminino , Humanos , Síndrome do Ovário Policístico/diagnóstico , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Vitamina D/sangue , Adulto JovemRESUMO
As a result of societal expectations and to avoid societal homophobia, many lesbians and gay men in China marry heterosexual partners and do not disclose their own sexual orientation. This study used qualitative methods to explore why gay men enter into such marriages of convenience. A total of 17 in-depth interviews were conducted with lesbians and gay men who had entered "formality marriages." All interviews were digitally recorded for transcription; transcripts were analyzed using grounded theory to determine themes. The reasons for engaging in formality marriage can be grouped into broad categories, including: maintaining mianzi (reputation) and lizi (inner reality), avoiding moral distress, social discrimination, working in tizhi (social systems), accounting for their social relationships, and fulfilling filial piety. From our model we can see growing up as a member of a minority sexual orientation group means being discriminated against and marginalized in the family, work place, community, and society at large. Formality marriages not only offer a way to maintain one's personal and family reputation ( mianzi) in different contexts, but also avoid moral distress and maintain a personal private sexual orientation ( lizi) with their own homosexual partner. Formality marriage serves as a compromise to ensure cultural continuity, and it harmonizes individuals' interpersonal relationships and traditional Chinese family values. Understanding the reasons for formality marriage practices can help health professionals to create public health campaigns to dispel stereotypes and stigma about homosexuality, and to develop culturally sensitive services for homosexual populations.
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Cultura , Casamento/psicologia , Minorias Sexuais e de Gênero/psicologia , Discriminação Social , Estigma Social , Adulto , China , Revelação , Feminino , Humanos , Relações Interpessoais , Entrevistas como Assunto , Masculino , Modelos TeóricosRESUMO
Chronic pain patients often have psychiatric disorders that negatively influence their responses to treatment. Also, many of them have dysfunctional beliefs and coping strategies, even if they do not meet DSM-5 criteria for a psychiatric disorder. Physiatrists should have a low threshold for referring both groups of patients for mental health services. This article describes psychiatric disorders that are highly prevalent among pain patients and also describes psychological processes that contribute to poor coping by the patients. Finally, it discusses factors that a physiatrist should consider in deciding whether to refer patients to psychiatrists versus psychologists.
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Dor Crônica/psicologia , Dor Crônica/reabilitação , Transtornos Mentais/psicologia , Adaptação Psicológica , Humanos , Manejo da Dor , Medição da Dor , Encaminhamento e ConsultaRESUMO
OBJECTIVE: The prevalence of opioid therapy for chronic noncancer pain has increased dramatically in recent years, with a parallel increase in opioid abuse, misuse and deaths from accidental overdose. We review epidemiological and clinical data that point to the important roles psychiatric disorders have in the use and abuse of opioids in patients with chronic pain. METHOD: We conducted literature searches on the PubMed with the key phrases "chronic pain" and "opioid therapy" and selected those articles on the epidemiology of comorbidity between chronic pain and psychiatric disorders, the trends in long-term opioid therapy and the clinical trials that involved using opioid therapy for chronic pain or for mental health disorders. We then thoroughly reviewed the bibliography of all relevant articles to identify additional papers to be included in the present review. RESULTS: Chronic pain is highly comorbid with common psychiatric disorders. Patients with mental health and substance abuse disorders are more likely to receive long-term opioid therapy for chronic pain and more likely to have adverse outcomes from this therapy. Although opioids may exert brief antidepressant and anxiolytic effects in some patients with depression or anxiety, there is scant evidence for long-term benefit from opioid treatment of psychiatric disorders. CONCLUSIONS: Opioids may be used in current clinical practice as the de facto and only psychiatric treatment for patients with chronic pain, despite little evidence for sustained benefit. The opioid epidemic thus reflects a serious unmet need for better recognition and treatment of common mental health problems in patients with chronic pain. Psychiatry is the missing P in chronic pain care.
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Analgésicos Opioides/uso terapêutico , Dor Crônica/terapia , Transtornos Mentais/terapia , Serviços de Saúde Mental , Transtornos Relacionados ao Uso de Opioides , Manejo da Dor/métodos , Dor Crônica/epidemiologia , Dor Crônica/psicologia , Comorbidade , Humanos , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Manejo da Dor/psicologiaRESUMO
Opioid therapy offers the promise of reducing the burden of chronic pain in not just individual patients, but among the broad population of patients with chronic pain. Randomized trials have demonstrated that opioid therapy for up to 12-16weeks is superior to placebo, but have not addressed longer-term use. In the United States, opioid sales have quadrupled during 2000-2010, with parallel increases in opioid accidental overdose deaths and substance abuse admissions. Clinical use of long-term opioid therapy is characterized by a pattern of adverse selection, where high-risk patients are prescribed high-risk opioid regimens. This adverse selection may link these trends in use, abuse, and overdose. Long-term opioid therapy appears to be associated with iatrogenic harm to the patients who receive the prescriptions and to the general population. The United States has, in effect, conducted an experiment of population-wide treatment of chronic pain with long-term opioid therapy. The population-wide benefits have been hard to demonstrate, but the harms are now well demonstrated.
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Analgésicos Opioides/uso terapêutico , Dor Crônica/tratamento farmacológico , Dor Crônica/epidemiologia , Medicina Baseada em Evidências , Transtornos Relacionados ao Uso de Opioides/mortalidade , Medição da Dor/efeitos dos fármacos , Dor Crônica/diagnóstico , Humanos , Medição da Dor/estatística & dados numéricos , Prevalência , Medição de Risco , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos/epidemiologiaRESUMO
OBJECTIVES: Chronic opioid therapy (COT) for chronic noncancer pain (CNCP) is characterized by both high rates of patient-initiated discontinuation and by perceived helpfulness among those who sustain opioid use. This study examines predictors of the desire to cut down or stop opioid therapy among patients receiving COT who report that opioids are helpful for relieving pain. METHODS: We conducted a cross-sectional survey of 1737 selected patients receiving COT for CNCP who perceived opioids to be helpful in relieving their pain. Ambivalence about opioid use was assessed by agreement/disagreement with a statement indicating that they would like to stop or cut down the use of prescribed opioid medications. Depression was measured with the 8-item Patient Health Questionnaire. RESULTS: A high percentage (43.3%) of survey respondents who found opioids helpful also reported the desire to stop or cut down opioids. Half of these patients reporting the desire to stop or cut down were clinically depressed, compared with a third of those not wanting to stop or cut down, a highly significant difference after controlling for covariates (P<0.0001). The group wanting to stop or cut down opioid use also reported significantly higher levels of opioid-related psychosocial problems and opioid control concerns. DISCUSSION: There are high rates of ambivalence about opioid use among COT recipients who consider opioids helpful for pain relief. Depressed patients are more likely to be ambivalent about use of prescribed opioids. Eliciting patient ambivalence may be helpful in patients who are not benefiting from long-term opioid use as an initial step toward consideration of discontinuation.
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Analgésicos Opioides/uso terapêutico , Analgésicos/uso terapêutico , Dor Crônica , Depressão/etiologia , Motivação , Adulto , Idoso , Idoso de 80 Anos ou mais , Dor Crônica/complicações , Dor Crônica/tratamento farmacológico , Dor Crônica/psicologia , Estudos Transversais , Depressão/tratamento farmacológico , Depressão/psicologia , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Motivação/fisiologia , Medição da Dor , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Inquéritos e Questionários , Telefone , Adulto JovemRESUMO
Much current vision research is predicated on the idea--and a rapidly growing body of evidence--that visual percepts are generated according to the empirical significance of light stimuli rather than their physical characteristics. As a result, an increasing number of investigators have asked how visual perception can be rationalized in these terms. Here, we compare two different theoretical frameworks for predicting what observers actually see in response to visual stimuli: Bayesian decision theory and empirical ranking theory. Deciding which of these approaches has greater merit is likely to determine how the statistical operations that apparently underlie visual perception are eventually understood.
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Teorema de Bayes , Modelos Psicológicos , Percepção Visual , Humanos , Iluminação , Ilusões Ópticas , Estimulação Luminosa/métodos , Psicofísica , Retina/fisiologiaRESUMO
One of the most intriguing of the many discrepancies between perceived spatial relationships and the physical structure of visual stimuli is the Poggendorff illusion, when an obliquely oriented line that is interrupted no longer appears collinear. Although many different theories have been proposed to explain this effect, there has been no consensus about its cause. Here, we use a database of range images (i.e., images that include the distance from the image plane of every pixel in the scene) to show that the probability distribution of the possible locations of line segments across an interval in natural environments can fully account for all of the behavior of this otherwise puzzling phenomenon.
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Modelos Psicológicos , Ilusões Ópticas/fisiologia , Percepção Visual/fisiologia , Bases de Dados Factuais , HumanosRESUMO
The Müller-Lyer effect, the apparent difference in the length of a line as the result of its adornment with arrowheads or arrow tails, is the best known and most controversial of the classical geometrical illusions. By sampling a range-image database of natural scenes, we show that the perceptual effects elicited by the Müller-Lyer stimulus and its major variants are correctly predicted by the probability distributions of the possible physical sources underlying the relevant retinal images. These results support the conclusion that the Müller-Lyer illusion is a manifestation of the probabilistic strategy of visual processing that has evolved to contend with the uncertain provenance of retinal stimuli.
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Percepção de Forma , Processamento de Imagem Assistida por Computador , Ilusões Ópticas , Percepção Visual , Orientação , Probabilidade , Percepção EspacialRESUMO
Visual stimuli that entail the intersection of two or more straight lines elicit a variety of well known perceptual anomalies. Preeminent among these anomalies are the systematic overestimation of acute angles, the underestimation of obtuse angles, and the misperceptions of line orientation exemplified in the classical tilt, Zollner, and Hering illusions. Here we show that the probability distributions of the possible real-world sources of projected lines and angles derived from a range-image database of natural scenes accurately predict each of these perceptual peculiarities. These findings imply that the perception of angles and oriented lines is determined by the statistical relationship between geometrical stimuli and their physical sources in typical visual environments.
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Percepção de Forma , Natureza , Ilusões Ópticas/fisiologia , Percepção Espacial , Orientação , Probabilidade , Percepção VisualRESUMO
The term "size contrast and assimilation" refers to a large class of geometrical illusions in which the apparent sizes of identical visual targets in various contexts are different. Here we have examined whether these intriguing discrepancies between physical and perceived size can be explained by a visual process in which percepts are determined by the probability distribution of the possible real-world sources of retinal stimuli. To test this idea, we acquired a range image database of natural scenes that specified the location of every image point in 3-D space. By sampling the possible physical sources of various size contrast or assimilation stimuli in the database, we determined the probability distributions of the size of the target in the images generated by these sources. For each of the various stimuli tested, these probability distributions of target size in different contexts accurately predicted the perceptual effects reported in psychophysical studies. We conclude that size contrast and assimilation effects are a further manifestation of a fundamentally probabilistic process of visual perception.
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Percepção de Forma/fisiologia , Modelos Neurológicos , Modelos Estatísticos , Natureza , Ilusões Ópticas , Probabilidade , Percepção de Tamanho/fisiologia , Teorema de Bayes , Simulação por Computador , Bases de Dados como Assunto , Processamento de Imagem Assistida por Computador , Percepção Espacial/fisiologiaRESUMO
The similarity of musical scales and consonance judgments across human populations has no generally accepted explanation. Here we present evidence that these aspects of auditory perception arise from the statistical structure of naturally occurring periodic sound stimuli. An analysis of speech sounds, the principal source of periodic sound stimuli in the human acoustical environment, shows that the probability distribution of amplitude-frequency combinations in human utterances predicts both the structure of the chromatic scale and consonance ordering. These observations suggest that what we hear is determined by the statistical relationship between acoustical stimuli and their naturally occurring sources, rather than by the physical parameters of the stimulus per se.