Category: Nevin Manimala

Proc Natl Acad Sci U S A. 2024 Jun 18;121(25):e2312293121. doi: 10.1073/pnas.2312293121. Epub 2024 Jun 10.

ABSTRACT

The perception of sensory attributes is often quantified through measurements of sensitivity (the ability to detect small stimulus changes), as well as through direct judgments of appearance or intensity. Despite their ubiquity, the relationship between these two measurements remains controversial and unresolved. Here, we propose a framework in which they arise from different aspects of a common representation. Specifically, we assume that judgments of stimulus intensity (e.g., as measured through rating scales) reflect the mean value of an internal representation, and sensitivity reflects a combination of mean value and noise properties, as quantified by the statistical measure of Fisher information. Unique identification of these internal representation properties can be achieved by combining measurements of sensitivity and judgments of intensity. As a central example, we show that Weber’s law of perceptual sensitivity can coexist with Stevens’ power-law scaling of intensity ratings (for all exponents), when the noise amplitude increases in proportion to the representational mean. We then extend this result beyond the Weber’s law range by incorporating a more general and physiology-inspired form of noise and show that the combination of noise properties and sensitivity measurements accurately predicts intensity ratings across a variety of sensory modalities and attributes. Our framework unifies two primary perceptual measurements-thresholds for sensitivity and rating scales for intensity-and provides a neural interpretation for the underlying representation.

PMID:38857385 | DOI:10.1073/pnas.2312293121

J Clin Neurophysiol. 2024 Jun 10. doi: 10.1097/WNP.0000000000001088. Online ahead of print.

ABSTRACT

INTRODUCTION: Transcutaneous electrical stimulation is used to stimulate the dorsal roots of the cauda equina. Multiple elicited responses recorded in the lower extremity muscles are called posterior root muscle reflexes (PRMRs). Normal PRMR values in the muscles of healthy lower extremities have yet to be determined.

METHODS: Thirty subjects without known lumbosacral spinal root illness were included in this study. Subsequently, they were subjected to transcutaneous electrical stimulation of the cauda equina. Posterior root muscle reflex was recorded in the four muscle groups of both lower extremities. We elicited multiple PRMR and examined their characteristics in order to establish normal electrophysiological parameter values.

RESULTS: Posterior root muscle reflex was successfully elicited in the tibialis anterior (96.7%), gastrocnemius (100%), quadriceps femoris (93.3%), and hamstring (96.7%). No statistically significant differences were found in the intensity of stimulation, latencies, or area under the PRMR between the right and left leg muscles. The area under PRMR varied significantly among the participants. Higher body weight and abdominal girth showed a significant positive correlation with stimulation intensity for eliciting PRMR, and a significant negative correlation with the area under PRMR. Older age showed a significant negative correlation with the success of eliciting PRMR and the area under the PRMR.

CONCLUSIONS: Posterior root muscle reflex is a noninvasive and successful method for eliciting selective reflex responses of cauda equina posterior roots. Obtained values could be used in future studies to evaluate the utility of this methodology in clinical practice. This methodology could improve testing of the proximal lumbosacral nervous system functional integrity.

PMID:38857374 | DOI:10.1097/WNP.0000000000001088

Am Nat. 2024 Jul;204(1):15-29. doi: 10.1086/730261. Epub 2024 May 17.

ABSTRACT

AbstractAdaptation to replicated environmental conditions can be remarkably predictable, suggesting that parallel evolution may be a common feature of adaptive radiation. An open question, however, is how phenotypic variation itself evolves during repeated adaptation. Here, we use a dataset of morphological measurements from 35 populations of threespine stickleback, consisting of 16 parapatric lake-stream pairs and three marine populations, to understand how phenotypic variation has evolved during transitions from marine to freshwater environments and during subsequent diversification across the lake-stream boundary. We find statistical support for divergent phenotypic covariance (P) across populations, with most diversification of P occurring among freshwater populations. Despite a close correspondence between within-population phenotypic variation and among-population divergence, we find that variation in P is unrelated to total variation in population means across the set of populations. For lake-stream pairs, we find that theoretical predictions for microevolutionary change can explain more than 30% of divergence in P matrices across the habitat boundary. Together, our results indicate that divergence in variance structure occurs primarily in dimensions of trait space with low phenotypic integration, correlated with disparate lake and stream environments. Our findings illustrate how conserved and divergent features of multivariate variation can underlie adaptive radiation.

PMID:38857340 | DOI:10.1086/730261

Acad Med. 2024 Jun 7. doi: 10.1097/ACM.0000000000005782. Online ahead of print.

ABSTRACT

PURPOSE: The COVID-19 pandemic prompted training institutions and national credentialing organizations to administer examinations virtually. This study compared task difficulty, examiner grading, candidate performance, and other psychometric properties between in-person and virtual standardized oral examinations (SOEs) administered by the American Board of Anesthesiology.

METHOD: This retrospective study included SOEs administered in person from March 2018 through March 2020 and virtually from December 2020 through November 2021. The in-person and virtual SOEs share the same structure, including 4 tasks of preoperative evaluation, intraoperative management, postoperative care, and additional topics. The Many-Facet Rasch Model was used to estimate candidate performance, examiner grading severity, and task difficulty for the in-person and virtual SOEs separately; the virtual SOE was equated to the in-person SOE by common examiners and all tasks. The independent-samples and partially overlapping-samples t tests were used to compare candidate performance and examiner grading severity between these 2 formats, respectively.

RESULTS: In-person (n = 3,462) and virtual (n = 2,959) first-time candidates were comparable in age, sex, race and ethnicity, and whether they were U.S. medical school graduates. The mean (standard deviation [SD]) candidate performance was 2.96 (1.76) logits for the virtual SOE, which was statistically significantly better than that for the in-person SOE (mean [SD], 2.86 [1.75]; Welch independent-samples t test, P = .02); however, the effect size was negligible (Cohen d = 0.06). The difference in the grading severity of examiners who rated the in-person (n = 398; mean [SD], 0.00 [0.73]) vs virtual (n = 341; mean [SD], 0.07 [0.77]) SOE was not statistically significant (Welch partially overlapping-samples t test, P = .07).

CONCLUSIONS: Candidate performance and examiner grading severity were comparable between the in-person and virtual SOEs, supporting the reliability and validity of the virtual oral exam in this large-volume, high-stakes setting.

PMID:38857338 | DOI:10.1097/ACM.0000000000005782

Circulation. 2024 Jun 11;149(24):1931-1934. doi: 10.1161/CIRCULATIONAHA.123.067754. Epub 2024 Jun 10.

NO ABSTRACT

PMID:38857329 | DOI:10.1161/CIRCULATIONAHA.123.067754

J ECT. 2024 Jun 10. doi: 10.1097/YCT.0000000000001009. Online ahead of print.

ABSTRACT

Despite years of research, we are still not able to reliably predict who might benefit from electroconvulsive therapy (ECT) treatment. As we exhaust what is possible using traditional statistical analysis, ECT remains a good candidate for machine learning approaches due to the large data sets with data captured through electroencephalography (EEG) and other objective measures. A systematic review of 6 databases led to the full-text examination of 26 articles using machine learning approaches in examining data predicting response to ECT treatment. The identified articles used a wide variety of data types covering structural and functional imaging data (n = 15), clinical data (n = 5), a combination of clinical and imaging data (n = 2), EEG (n = 3), and social media posts (n = 1). The clinical indications in which response prediction was assessed were depression (n = 21) and psychosis (n = 4). Changes in multiple anatomical regions in the brain were identified as holding a predictive value for response to ECT. These primarily centered on the limbic system and associated networks. Clinical features predicting good response to ECT in depression included shorter duration, lower severity, higher medication dose, psychotic features, low cortisol levels, and positive family history. It has also been possible to predict the likelihood of relapse of readmission with psychosis after ECT treatment, including a better response if higher transfer entropy was calculated from EEG signals. A transdisciplinary approach with an international consortium collecting a wide range of retrospective and prospective data may help to refine and extend these outcomes and translate them into clinical practice.

PMID:38857315 | DOI:10.1097/YCT.0000000000001009

PLoS One. 2024 Jun 10;19(6):e0304169. doi: 10.1371/journal.pone.0304169. eCollection 2024.

ABSTRACT

This study aimed to assess the effect of intraocular pressure (IOP) changes on biometry and intraocular lens (IOL) power calculation in patients diagnosed with primary open-angle glaucoma (POAG) and ocular hypertension (OHT). This prospective non-randomized cohort study enrolled patients with diagnosed POAG and OHT, presenting with IOP levels exceeding 25 mmHg. Thai Clinical Trials Registry number was TCTR20180912007. Optical biometry, encompassing measurements such as corneal thickness (CCT), keratometry, anterior chamber depth (ACD), and axial length, was conducted before and after IOP reduction. The IOL power was also determined using the SRK/T formula. The main outcomes measured were alterations in biometry and IOL power. Correlations between IOP, biometric parameters, and IOL power were analyzed. In total, 28 eyes were included in the study, with a mean patient age of 65.71±10.2 years. After IOP reduction, all biometric parameters, except CCT and ACD, exhibited a decrease without reaching statistical significance (all p>0.05). Meanwhile, IOL power showed a slight increase of 0.214±0.42 diopters (P = 0.035). The correlation between IOP and biometric parameters was found to be weak. However, there was a moderate correlation between IOP and IOL power (r2 = 0.267). Notably, IOL power tended to increase by more than 0.5 diopters when IOP decreased by more than 10 mmHg (p < 0.001). In conclusion, changes in IOP among patients with POAG and OHT do not significantly impact biometry and IOL power calculations. Nonetheless, it may be prudent to consider a slight adjustment in IOL power when IOP is lowered by more than 10 mmHg.

PMID:38857282 | DOI:10.1371/journal.pone.0304169

PLoS One. 2024 Jun 10;19(6):e0300851. doi: 10.1371/journal.pone.0300851. eCollection 2024.

ABSTRACT

BACKGROUND: Cholecystectomy remains the standard management for acute cholecystitis. Given that rates of nonoperative management have increased, we hypothesize the existence of significant hospital-level variability in operative rates. Thus, we characterized patients who were managed nonoperatively at normal and lower operative hospitals (>90th percentile).

METHODS: All adult admissions for acute cholecystitis were queried using the 2016-2019 Nationwide Readmissions Database. Centers were ranked by nonoperative rate using multi-level, mixed effects modeling. Hospitals in the top decile of nonoperative rate (>9.4%) were classified as Low Operative Hospitals (LOH; others:nLOH). Separate regression models were created to determine factors associated with nonoperative management at LOH and nLOH.

RESULTS: Of an estimated 418,545 patients, 9.9% were managed at 880 LOH. Multilevel modeling demonstrated that 20.6% of the variability was due to hospital factors alone. After adjustment, older age (Adjusted Odds Ratio [AOR] 1.02/year, 95% Confidence Interval [CI] 1.01-1.02) and public insurance (Medicare AOR 1.31, CI 1.21-1.43 and Medicaid AOR 1.43, CI 1.31-1.57; reference: Private Insurance) were associated with nonoperative management at LOH. These were similar at nLOH. At LOH, SNH status (AOR 1.17, CI 1.07-1.28) and small institution size (AOR 1.20, CI 1.09-1.34) were associated with increased odds of nonoperative management.

CONCLUSION: We noted a significant variability in the interhospital variation of the nonoperative management of acute cholecystitis. Nevertheless, comparable clinical and socioeconomic factors contribute to nonoperative management at both LOH and non-LOH. Directed strategies to address persistent non-clinical disparities are necessary to minimize deviation from standard protocol and ensure equitable care.

PMID:38857278 | DOI:10.1371/journal.pone.0300851

PLoS Negl Trop Dis. 2024 Jun 10;18(6):e0012238. doi: 10.1371/journal.pntd.0012238. Online ahead of print.

ABSTRACT

BACKGROUND: Rabies, caused by the rhabdovirus, is a fatal zoonotic disease with over 59,000 annual deaths globally. Asia and Africa account for 95%, with India leading, followed by China. In Pakistan, where it’s endemic, over 50,000 cases are reported yearly. Controlling rabid dog populations through vaccination is crucial in curbing mortality. This research aimed to evaluate healthcare professionals’ knowledge, attitudes, and practices concerning rabies in Peshawar, Pakistan.

METHODS: The study was conducted at different tertiary care hospitals in Peshawar, Pakistan from 16 August 2021 to 15 February 2022. Cross-sectional research was conducted to gather data from a total of 100 healthcare workers representing different sections within the healthcare field, including Medical Officers, House Officers, Faculty Staff, Nurses, and Paramedics. Data on knowledge, attitudes, and practices about rabies were collected using a standardized questionnaire. The data analysis included using descriptive statistics and chi-square testing to ascertain potential correlations.

RESULTS: Among the healthcare professionals, 68 (68%) were males, and 32 (32%) were females. Profession-wise, the included professionals were Nurses 31 (31%), Medical Officers 27 (27%), House officers 26 (26%), paramedical staff 13 (13%), and faculty staff 3 (3%). 91 (91%) and 9 (9%) healthcare professionals responded that dogs and cats are responsible for rabies transmission, respectively. Moreover, 82 (82%) individuals responded that animal bite plays a vital role in the transmission of rabies, whilst 76 (76%) individuals responded that rabies transferred from human to human. 82 (82%) individuals replied that the anti-rabies vaccine (ARV) is the treatment of choice for rabies. Furthermore, 78 (78%) individuals responded that ARV is safe in pregnancy and lactation. Moreover, after being asked about the perception of the health care professionals about the failure in controlling rabies, their responses were unavailability of ARV/RIG 41 (41%), lack of control of stray dogs 34 (34%), lack of awareness 20 (20%). The study revealed statistically significant correlations between healthcare occupations and variables: knowledge of animals responsible for transmitting rabies (p = 0.024) and awareness of human-to-human transmission (p = 0.007). Significant disparities were noted in understanding rabies transmission through contaminated water (p = 0.002). There were variations in attitudes and practices seen across different positions, particularly about views about home treatments (p = 0.033) and the perceived effectiveness of cleansing bite wounds (p = 0.010). Disparities in perceptions of rabies treatment and the accessibility of anti-rabies vaccines and immunoglobulin were observed, with variations based on individual roles.

CONCLUSION: The present research elucidates variations in rabies knowledge, attitudes, and practices among healthcare workers, specifically concerning their respective roles. Tailored training programs and standardized practices play a crucial role in mitigating these discrepancies, fostering a greater understanding of rabies, and enhancing the quality of patient treatment. It is recommended that future studies undertake an assessment of the efficacy of therapies and advocate for the adoption of collaborative One Health strategies in the realm of rabies management.

PMID:38857276 | DOI:10.1371/journal.pntd.0012238

PLoS One. 2024 Jun 10;19(6):e0297917. doi: 10.1371/journal.pone.0297917. eCollection 2024.

ABSTRACT

What is the role of working memory over the course of non-native speech category learning? Prior work has predominantly focused on how working memory might influence learning assessed at a single timepoint. Here, we substantially extend this prior work by examining the role of working memory on speech learning performance over time (i.e., over several months) and leverage a multifaceted approach that provides key insights into how working memory influences learning accuracy, maintenance of knowledge over time, generalization ability, and decision processes. We found that the role of working memory in non-native speech learning depends on the timepoint of learning and whether individuals learned the categories at all. Among learners, across all stages of learning, working memory was associated with higher accuracy as well as faster and slightly more cautious decision making. Further, while learners and non-learners did not have substantially different working memory performance, learners had faster evidence accumulation and more cautious decision thresholds throughout all sessions. Working memory may enhance learning by facilitating rapid category acquisition in initial stages and enabling faster and slightly more careful decision-making strategies that may reduce the overall effort needed to learn. Our results have important implications for developing interventions to improve learning in naturalistic language contexts.

PMID:38857268 | DOI:10.1371/journal.pone.0297917