Publications

Vision can be viewed as a continuous information processing, yet its underlying system properties have not been fully understood. Studies of visual serial dependence suggest that current perception is often biased by the preceding stimuli, raising the possibility of Markov-like processing-where only the previous state (not the ones before) affects the current one. In the current study, participants rated faces on two of three traits (attractiveness, trustworthiness, and dominance), presented in randomized sequences so each rating could be preceded by the same or a different trait. This design allowed us to examine how prior input (the face) and prior output (the perception) influence current judgment. Using derivative of Gaussian, Markov chain, and linear mixed-effects modeling, we found that serial dependence was disrupted-and both memoryless property and Markov assumptions were violated-when alternating between two traits for attractiveness and dominance but not under other conditions. These findings suggest that different facets of (presumably) the same visual computation can exhibit asymmetrical system properties. More broadly, our work shows how serial dependence can serve as a powerful tool to probe the underlying rules by which the visual system integrates past and present information.

The human visual system prioritizes dynamic stimuli, which attract attention and more readily break suppression to reach perceptual awareness. Here, we investigated whether dynamic changes in contrast-either increasing or decreasing-are equally effective in facilitating the breakthrough of suppressed stimuli during binocular rivalry. In Experiment 1a, we found that contrast increases led to significantly faster breakthroughs into perceptual dominance compared with decreases. Notably, increases accelerated breakthrough relative to the unchanged baseline, whereas decreases delayed it. Experiments 1b and 1c replicated the results of Experiment 1a using, respectively, a briefer contrast change (10 ms instead of 100 ms) and partial breakthrough reports, confirming a robust asymmetry in the processing of suppressed stimuli between increases and decreases. In Experiment 2a, random dots moving in different random directions were presented dichoptically, making interocular conflict imperceptible and unreportable. We found that any change in intensity in such rivalry settings-regardless of increase or decrease-promoted perceptual dominance. By introducing motion stimuli into the Experiment 1 paradigm, Experiment 2b demonstrated that the divergence between Experiments 1 and 2 was not due to low-level stimulus differences. Taken together, our results reveal an asymmetric effect of contrast changes during binocular rivalry. This finding highlights the interplay between subliminal sensory processing of contrast changes and conscious awareness, shedding light on developing theoretical models of binocular rivalry.

The physical interactions among objects in the natural environment can cause dramatic changes in their shapes or patterns of motion, and those changes can provide reliable information to distinguish different types of events or materials. The present research was designed to investigate the identification of fluid materials. Observers viewed computer animations and static images of a shiny orange translucent fluid flowing from a tube into a glass jar, and they were asked to make confidence ratings about whether the depicted material looked like water/juice, oil/paint, honey/molasses, or caulk/toothpaste. The results reveal that observers can identify different types of fluid materials within broad overlapping categories based on qualitative characteristics of fluid flow that only occur within limited ranges of viscosity.

PURPOSE: The prevalence of myopia varies significantly across the globe. This may be a consequence of differences in exposure to lifestyle risk factors or differences in genetic susceptibility across ancestry groups. "Trans-ancestry genetic correlation" quantifies the similarity in genetic predisposition to a trait or disease between different populations. We estimated the trans-ancestry genetic correlation of refractive error across Europeans, South Asians, East Asians, and Africans using recently developed approaches.

METHODS: Two methods were applied: (1) trans-ancestry genetic correlation with unbalanced data resources (TAGC-UDR) and (2) trans-ancestry bivariate genomic-relatedness-based restricted maximum-likelihood (TAB-GREML). TAGC-UDR analyses were carried out for UK Biobank participants of European (n = 3500), East Asian (n = 972), South Asian (n = 4303), and African (n = 3877) ancestry. TAB-GREML analyses were carried out for participants of European (n = 10,000), South Asian (n = 4303), and African (n = 3877) ancestry.

RESULTS: TAGC-UDR analyses suggested the trans-ancestry genetic correlation of refractive error was in the range 0.7-1.0 for the European versus African, European versus East Asian, and European versus South Asian ancestry pairs. The TAB-GREML estimates were consistent with the TAGC-UDR findings. Precision of the estimates was limited, reflecting the modest sample sizes of the non-European samples.

CONCLUSIONS: These results support and extend previous work suggesting that genetic susceptibility to refractive error is largely shared across Europeans, Africans, and South Asians. This suggests geographical differences in myopia prevalence are mostly driven by lifestyle factors or rare genetic variants not considered in the current work.

PURPOSE: Given the common use of Food and Drug Administration (FDA)-regulated drugs and medical devices, clinicians need to understand FDA regulation and clinical trial interpretation to provide optimal and informed patient care. Medical and pharmacy school curriculum guidelines recommend education on these topics, but no studies have assessed health professional student knowledge of FDA approvals. This study assessed knowledge about FDA regulation and clinical research evidence interpretation among final-year health professional students.

METHOD: The authors designed a 24-item survey questionnaire that asked trainees to self-report (1) exposure to learning about FDA drug and medical device approval processes, (2) understanding of FDA approval evidence requirements, and (3) ability to critically interpret trial design and evidence. After pretesting, all 333 final-year students in the medical, pharmacy, and family nurse practitioner schools at the University of California San Francisco were invited to complete the survey between January and April 2024.

RESULTS: Of 175 respondents (91 medical, 62 pharmacy, and 22 family nurse practitioner; response rate, 53%), 124 (71%) reported receiving teaching about FDA drug approvals, although 107 (90%) of these respondents described it as basic or cursory and 69 (58%) desired more teaching. Only 23 (14%) reported receiving teaching about medical device approvals. Despite 62 students (38%) rating their understanding of FDA drug approvals as moderately or extremely well, 5 (3%) correctly answered that drug approval requires neither statistically nor clinically significant results. Regarding clinical trial interpretation, only 25 students (17%) recognized the superiority of all-cause mortality end point data over surrogate measures and other end points.

CONCLUSIONS: Health professional students have limited understanding of the FDA approval process and the quality of evidence in studies of new medical products. Improving education about regulatory topics may strengthen how these future clinicians make decisions and communicate with patients about drugs and medical devices.

Hiccups is a reflex consisting of a sudden spasmodic contraction of the diaphragm causing shaking of the inspiratory muscles of the chest and abdomen, followed by the sudden closure of the glottis.1 Persistent hiccups, i.e., lasting longer than 48 hours, usually signify an underlying organic cause and must be evaluated. Gastroesophageal disorders such as aerophagia, peptic ulcer disease, esophagitis, gastritis, and pancreatitis are the common causes of persistent hiccups. Distal esophageal spasm (DES) usually presents with dysphagia and chest pain.2 There have been no case reports of DES presenting with hiccups as a primary complaint. Our patient presented with persistent hiccups as a primary complaint and was initially treated as gastroesophageal reflux disease-related hiccups. On further investigations, he was found to have DES, which completely resolved after peroral endoscopic myotomy procedure.

Total anomalous pulmonary venous connection (TAPVC) is a rare cyanotic congenital heart disease with abnormal drainage of pulmonary veins (PVs) into a systemic vein or right atrium (RA). It is divided into four types on the basis of anatomical pattern of drainage: supracardiac, cardiac, infracardiac, and mixed type. The mixed variant is further divided into the "3 + 1" and "2 + 2" patterns. Our series illustrates three of these subtypes, that is, "3 + 1" mixed type, cardiac type, and obstructive infracardiac type with PVs draining into portal vein.

A 46-year-old male nonsmoker presented to the outpatient department (OPD) with a history of progressively increasing breathlessness and central cyanosis since 1 month. He had a history of surgery for craniopharyngioma 6 years back and was on hormone replacement therapy. On evaluation, no cardiopulmonary cause was found for cyanosis. Patient was detected to have cirrhosis, possibly due to nonalcoholic fatty liver disease (NAFLD), and hepatopulmonary syndrome (HPS) was suspected as the cause for dyspnea and cyanosis, which was confirmed on workup. HPS as the first presentation of undiagnosed cirrhosis is relatively rare, although there are some case reports in the literature.

Marfan's syndrome is an autosomal dominant multisystem connective tissue disorder. It commonly presents with complications of aortic dissection, aortic root dilation, or mitral valve prolapse, or less likely with primary spontaneous pneumothorax (PSP) in the emergency department (ED). A 22-year-old male patient presented with undifferentiated chest pain to our ED. The patient was diagnosed with spontaneous pneumothorax, and further examination was suggestive of Marfan's syndrome. The patient was treated with intercostal tube placement and was advised to follow-up at a higher center for genetic testing. It would be prudent for ED physicians treating spontaneous pneumothorax to suspect, examine, and educate patients, guiding them to a confirmatory diagnosis.

A 40-year-old Indian lady presented with dirty-looking brown reticulate plaques on her chest, back, and neck of 10-year duration. The lesions were asymptomatic and improved only slightly with steroid creams. She was, otherwise, in good health and worked in a garments factory. Fungal scrapings were negative, and she declined a biopsy. With the working diagnosis of confluent and reticulated papillomatosis (CARP) of Gougerot and Carteaud, she was treated with 4 weeks of oral doxycycline. One month later, the rash had cleared dramatically, further confirming the diagnosis. This case highlights the importance of recognizing this uncommon, benign, yet cosmetically distressing condition and providing appropriate treatment.