scholarly journals A Bayesian computational model to investigate expert anticipation of a seemingly unpredictable ball bounce

2021 ◽  
Author(s):  
David Harris ◽  
Jamie North ◽  
Oliver Runswick
Keyword(s):  
Computational Model ◽  
Visual Cues ◽  
Computational Models ◽  
Information Sources ◽  
Sensory Information ◽  
Contextual Knowledge ◽  
Sources Of Information ◽  
Bayesian Brain ◽  
Markov Decision ◽  
Bounce Height

During dynamic and time-constrained sporting tasks performers rely on both online perceptual information and prior contextual knowledge to make effective anticipatory judgments. It has been suggested that performers may integrate these sources of information in an approximately Bayesian fashion, by weighting available information sources according to their expected precision. In the present work, we extended Bayesian brain approaches to anticipation by using formal computational models to estimate how performers weighted different information sources when anticipating the bounce direction of a rugby ball. Both recreational (novice) and professional (expert) rugby players (n = 58) were asked to predict the bounce height of an oncoming rugby ball in a temporal occlusion paradigm. A Bayesian computational model, based on a partially observable Markov decision process, was fitted to observed responses to estimate participants’ weighting of online sensory cues and prior beliefs about ball bounce height. The results showed that experts were more sensitive to online sensory information, but that neither experts nor novices relied heavily on contextual priors in this task. Experts, but not novices, were observed to down-weight contextual priors in their anticipatory decisions as later and more precise visual cues emerged, as predicted by Bayesian and active inference accounts of perception.

CSBPI_Site：Multi-Information Sources of Features to RNA Binding Sites Prediction

2021 ◽  
Vol 15 ◽  
Author(s):  
Lichao Zhang ◽  
Zihong Huang ◽  
Liang Kong
Keyword(s):  
Computational Model ◽  
Binding Sites ◽  
Noncoding Rna ◽  
Computational Models ◽  
Information Sources ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Gradient Boosting ◽  
Position Information ◽  
Rna Binding Sites

Background: RNA-binding proteins establish posttranscriptional gene regulation by coordinating the maturation, editing, transport, stability, and translation of cellular RNAs. The immunoprecipitation experiments could identify interaction between RNA and proteins, but they are limited due to the experimental environment and material. Therefore, it is essential to construct computational models to identify the function sites. Objective: Although some computational methods have been proposed to predict RNA binding sites, the accuracy could be further improved. Moreover, it is necessary to construct a dataset with more samples to design a reliable model. Here we present a computational model based on multi-information sources to identify RNA binding sites. Method: We construct an accurate computational model named CSBPI_Site, based on xtreme gradient boosting. The specifically designed 15-dimensional feature vector captures four types of information (chemical shift, chemical bond, chemical properties and position information). Results: The satisfied accuracy of 0.86 and AUC of 0.89 were obtained by leave-one-out cross validation. Meanwhile, the accuracies were slightly different (range from 0.83 to 0.85) among three classifiers algorithm, which showed the novel features are stable and fit to multiple classifiers. These results showed that the proposed method is effective and robust for noncoding RNA binding sites identification. Conclusion: Our method based on multi-information sources is effective to represent the binding sites information among ncRNAs. The satisfied prediction results of Diels-Alder riboz-yme based on CSBPI_Site indicates that our model is valuable to identify the function site.

scholarly journals Bayesian and “Anti-Bayesian” Biases in Sensory Integration for Action and Perception in the Size–Weight Illusion

2010 ◽  
Vol 103 (3) ◽  
pp. 1518-1531 ◽  
Author(s):  
Jordan B. Brayanov ◽  
Maurice A. Smith
Keyword(s):  
Motor System ◽  
Information Sources ◽  
Sensory Information ◽  
Motor Command ◽  
Accurate Estimation ◽  
Proprioceptive Information ◽  
Weight Estimation ◽  
Sources Of Information ◽  
Hand Motion ◽  
Weight Illusion

Which is heavier: a pound of lead or a pound of feathers? This classic trick question belies a simple but surprising truth: when lifted, the pound of lead feels heavier—a phenomenon known as the size–weight illusion. To estimate the weight of an object, our CNS combines two imperfect sources of information: a prior expectation, based on the object's appearance, and direct sensory information from lifting it. Bayes' theorem (or Bayes' law) defines the statistically optimal way to combine multiple information sources for maximally accurate estimation. Here we asked whether the mechanisms for combining these information sources produce statistically optimal weight estimates for both perceptions and actions. We first studied the ability of subjects to hold one hand steady when the other removed an object from it, under conditions in which sensory information about the object's weight sometimes conflicted with prior expectations based on its size. Since the ability to steady the supporting hand depends on the generation of a motor command that accounts for lift timing and object weight, hand motion can be used to gauge biases in weight estimation by the motor system. We found that these motor system weight estimates reflected the integration of prior expectations with real-time proprioceptive information in a Bayesian, statistically optimal fashion that discounted unexpected sensory information. This produces a motor size–weight illusion that consistently biases weight estimates toward prior expectations. In contrast, when subjects compared the weights of two objects, their perceptions defied Bayes' law, exaggerating the value of unexpected sensory information. This produces a perceptual size–weight illusion that biases weight perceptions away from prior expectations. We term this effect “anti-Bayesian” because the bias is opposite that seen in Bayesian integration. Our findings suggest that two fundamentally different strategies for the integration of prior expectations with sensory information coexist in the nervous system for weight estimation.

Prediction of Drug-Drug Interactions Related to Inhibition or Induction of Drug-Metabolizing Enzymes

2019 ◽  
Vol 19 (5) ◽  
pp. 319-336 ◽  
Author(s):  
Alexander V. Dmitriev ◽  
Alexey A. Lagunin ◽  
Dmitry А. Karasev ◽  
Anastasia V. Rudik ◽  
Pavel V. Pogodin ◽  
...  
Keyword(s):  
In Silico ◽  
Computational Models ◽  
Field Analysis ◽  
Pharmaceutical Chemistry ◽  
Sources Of Information ◽  
Metabolizing Enzymes ◽  
Physiologically Based Pharmacokinetic ◽  
Pharmacophore Models ◽  
Drug Metabolising Enzymes ◽  
In Silico Methods

Drug-drug interaction (DDI) is the phenomenon of alteration of the pharmacological activity of a drug(s) when another drug(s) is co-administered in cases of so-called polypharmacy. There are three types of DDIs: pharmacokinetic (PK), pharmacodynamic, and pharmaceutical. PK is the most frequent type of DDI, which often appears as a result of the inhibition or induction of drug-metabolising enzymes (DME). In this review, we summarise in silico methods that may be applied for the prediction of the inhibition or induction of DMEs and describe appropriate computational methods for DDI prediction, showing the current situation and perspectives of these approaches in medicinal and pharmaceutical chemistry. We review sources of information on DDI, which can be used in pharmaceutical investigations and medicinal practice and/or for the creation of computational models. The problem of the inaccuracy and redundancy of these data are discussed. We provide information on the state-of-the-art physiologically- based pharmacokinetic modelling (PBPK) approaches and DME-based in silico methods. In the section on ligand-based methods, we describe pharmacophore models, molecular field analysis, quantitative structure-activity relationships (QSAR), and similarity analysis applied to the prediction of DDI related to the inhibition or induction of DME. In conclusion, we discuss the problems of DDI severity assessment, mention factors that influence severity, and highlight the issues, perspectives and practical using of in silico methods.

Visual and Tactile Information About Object-Curvature Control Fingertip Forces and Grasp Kinematics in Human Dexterous Manipulation

2000 ◽  
Vol 84 (6) ◽  
pp. 2984-2997 ◽  
Author(s):  
Per Jenmalm ◽  
Seth Dahlstedt ◽  
Roland S. Johansson
Keyword(s):  
Visual Processing ◽  
Visual Cues ◽  
Grip Force ◽  
Center Of Mass ◽  
Precision Grip ◽  
Sensory Information ◽  
Afferent Input ◽  
Dependent Manner ◽  
Tactile Sensibility ◽  
Grasp Stability

Most objects that we manipulate have curved surfaces. We have analyzed how subjects during a prototypical manipulatory task use visual and tactile sensory information for adapting fingertip actions to changes in object curvature. Subjects grasped an elongated object at one end using a precision grip and lifted it while instructed to keep it level. The principal load of the grasp was tangential torque due to the location of the center of mass of the object in relation to the horizontal grip axis joining the centers of the opposing grasp surfaces. The curvature strongly influenced the grip forces required to prevent rotational slips. Likewise the curvature influenced the rotational yield of the grasp that developed under the tangential torque load due to the viscoelastic properties of the fingertip pulps. Subjects scaled the grip forces parametrically with object curvature for grasp stability. Moreover in a curvature-dependent manner, subjects twisted the grasp around the grip axis by a radial flexion of the wrist to keep the desired object orientation despite the rotational yield. To adapt these fingertip actions to object curvature, subjects could use both vision and tactile sensibility integrated with predictive control. During combined blindfolding and digital anesthesia, however, the motor output failed to predict the consequences of the prevailing curvature. Subjects used vision to identify the curvature for efficient feedforward retrieval of grip force requirements before executing the motor commands. Digital anesthesia caused little impairment of grip force control when subjects had vision available, but the adaptation of the twist became delayed. Visual cues about the form of the grasp surface obtained before contact was used to scale the grip force, whereas the scaling of the twist depended on visual cues related to object movement. Thus subjects apparently relied on different visuomotor mechanisms for adaptation of grip force and grasp kinematics. In contrast, blindfolded subjects used tactile cues about the prevailing curvature obtained after contact with the object for feedforward adaptation of both grip force and twist. We conclude that humans use both vision and tactile sensibility for feedforward parametric adaptation of grip forces and grasp kinematics to object curvature. Normal control of the twist action, however, requires digital afferent input, and different visuomotor mechanisms support the control of the grasp twist and the grip force. This differential use of vision may have a bearing to the two-stream model of human visual processing.

scholarly journals Numerical and Experimental Investigations on Vocal Fold Approximation in Healthy and Simulated Unilateral Vocal Fold Paralysis

2021 ◽  
Vol 11 (4) ◽  
pp. 1817
Author(s):  
Zheng Li ◽  
Azure Wilson ◽  
Lea Sayce ◽  
Amit Avhad ◽  
Bernard Rousseau ◽  
...  
Keyword(s):  
Computational Model ◽  
Vocal Fold ◽  
High Speed ◽  
Computational Models ◽  
Ex Vivo ◽  
Vocal Fold Paralysis ◽  
Future Application ◽  
Experimental Investigations ◽  
Type I ◽  
Mri Scans

We have developed a novel surgical/computational model for the investigation of unilat-eral vocal fold paralysis (UVFP) which will be used to inform future in silico approaches to improve surgical outcomes in type I thyroplasty. Healthy phonation (HP) was achieved using cricothyroid suture approximation on both sides of the larynx to generate symmetrical vocal fold closure. Following high-speed videoendoscopy (HSV) capture, sutures on the right side of the larynx were removed, partially releasing tension unilaterally and generating asymmetric vocal fold closure characteristic of UVFP (sUVFP condition). HSV revealed symmetric vibration in HP, while in sUVFP the sutured side demonstrated a higher frequency (10–11%). For the computational model, ex vivo magnetic resonance imaging (MRI) scans were captured at three configurations: non-approximated (NA), HP, and sUVFP. A finite-element method (FEM) model was built, in which cartilage displacements from the MRI images were used to prescribe the adduction, and the vocal fold deformation was simulated before the eigenmode calculation. The results showed that the frequency comparison between the two sides was consistent with observations from HSV. This alignment between the surgical and computational models supports the future application of these methods for the investigation of treatment for UVFP.

scholarly journals Existing Analytical Frameworks for Information Behaviour Don’t Fully Explain HIV/AIDS Information Exchange in Rural Communities in Ontario, Canada

2010 ◽  
Vol 5 (1) ◽  
pp. 135
Author(s):  
Kate Kelly
Keyword(s):  
Rural Communities ◽  
Information Seeking ◽  
Information Acquisition ◽  
Information Exchange ◽  
Information Sources ◽  
Sources Of Information ◽  
Theoretical Frameworks ◽  
Gate Keeping ◽  
Aids Information ◽  
Hiv Aids

A Review of: Veinot, T., Harris, R., Bella, L., Rootman, I., & Krajnak, J. (2006). HIV/AIDS Information exchange in rural communities: Preliminary findings from a three-province study. Canadian Journal of Information and Library Science, 30(3/4), 271-290. Objective –To explore and analyze, against three theoretical frameworks of information behaviours, how people with HIV/AIDS, their friends, and their family living in rural communities find information on HIV/AIDS. Design – Qualitative, individual, in-depth, semi-structured interviews. Setting – Two rural regions in Ontario, Canada. Subjects – Sixteen participants; 10 people with HIV/AIDS (PHAs) and 6 family members or friends. Methods – Participants were recruited through health care providers, social service agencies and through snowball sampling. Semi-structure interviews were conducted focusing on participants’ experience with HIV/AIDS, how they find and use information on HIV/AIDS, networks for information exchange and the effect of technology on information exchange. Interviews were taped, transcribed, analyzed qualitatively using NVivo software. Results were compared to three theoretical frameworks for information behaviour: 1. purposeful information seeking (i.e., the idea that people purposefully seek information to bridge perceived knowledge gaps); 2. non-purposeful or incidental information acquisition (i.e., the idea that people absorb information from going about daily activities); and 3. information gate keeping (i.e., the concept of private individuals who act as community links and filters for information gathering and dissemination). Main Results – Consistent with the theories: • PHAs prefer to receive information from people they have a personal relationship with, particularly their physician and especially other PHAs. • PHAs’ friends and families rely on their friends and family for information, and are particularly reliant upon the PHA in their lives. • Fear of stigma and discrimination cause some to avoid seeking information or to prefer certain sources of information, such as healthcare providers, who are bound by codes of professional conduct. • Emotional support is important in information provision and its presence supersedes the professional role of the provider (social workers and counsellors were identified as key information sources over medical professionals in this instance). Participants responded negatively to the perceived lack of support from providers including doubting the information provided. • PHAs monitor their worlds and keep up to date about HIV/AIDS. Inconsistent with theories: • Reliance on caregivers for information is not solely explained by fear of stigma or exposure. Rather, it is the specialized knowledge and immersion in HIV/AIDS which is valued. • The distinction between peer or kin sources of information and institutional information sources is less clear and relationships with professionals can turn personal over time. • Inter-personal connections include organisations, not just individuals, particularly AIDS Service Organizations and HIV specialist clinics. • Relatively few incidents of finding useful information about HIV/AIDS incidentally were described. The concept of information just being “out there” was not really applicable to rural settings, likely due to the lack of discussion within participant communities and local media. When it was discussed, participants reported being more likely to gain misinformation through their personal networks. • Incidental information acquisition originates mostly from professional and organisational sources. Participants identified posters, leaflets, and, for those who interacted with organisations, information via mail as contributing to current awareness. • The gate keeping concept does not capture all the information sharing activities undertaken by “gate keepers” in rural areas, and neither does it include formal providers of information, yet all PHAs interviewed identified formal providers as key sources. Conclusion – The findings reinforce some of the existing analytical framework theories, particularly the importance of affective components (i.e. emotional supports) of information seeking, the presence of monitoring behaviours, and of interpersonal sources of information. However, alternate theories may need to be explored as the role of institutional information sources in the lives of PHAs doesn’t match the theoretical predication and the “gate keeper” concept doesn’t capture a significant portion of that role in rural HIV/AIDS information exchange.

scholarly journals Who Guides Vaccination in the Portuguese Press? An Analysis of Information Sources

2021 ◽  
Vol 18 (4) ◽  
pp. 2189
Author(s):  
Andrea Langbecker ◽  
Daniel Catalan-Matamoros
Keyword(s):  
Content Analysis ◽  
Information Sources ◽  
Professional Associations ◽  
Scientific Journals ◽  
Sources Of Information ◽  
Media Agenda ◽  
The Media ◽  
University Scientists

Sources of information are a key part of the news process as it guides certain topics, influencing the media agenda. The goal of this study is to examine the most frequent voices on vaccines in the Portuguese press. A total of 300 news items were analysed via content analysis using as sources two newspapers from 2012 to 2017. Of all the articles, 97.7% included a source (n = 670). The most frequent were “governmental organisations”, “professional associations” and the “media”. Less frequent sources were “university scientists”, “governmental scientific bodies”, “consumer groups”, “doctors”, “scientific companies”, “NGOs” and “scientific journals”. Most articles used only non-scientific sources (n = 156). A total of 94 articles used both categories and 43 used exclusively scientific sources. Our findings support the assertion that media can be an instrument to disseminate information on vaccines. Nevertheless, despite being present in most articles, the number of sources per article was low, therefore not presenting a diversity of opinions and there was a lack of scientific voices, thus suggesting lower quality of the information being offered to the audience.

Sources of Performance Information in the Exercise Setting

1990 ◽  
Vol 12 (1) ◽  
pp. 56-65 ◽  
Author(s):  
Vicki Ebbeck
Keyword(s):  
Goal Setting ◽  
Muscle Development ◽  
Information Sources ◽  
Weight Training ◽  
Function Analysis ◽  
Information Source ◽  
Student Feedback ◽  
Sources Of Information ◽  
Perceived Effort ◽  
Gender Groups

This study examined the sources of information used by adult exercisers to judge performance. Of particular interest was the investigation of gender differences. Subjects, 271 adults (174 males, 97 females) who were enrolled in a university weight training program, completed a questionnaire designed to evaluate the importance of 12 information sources in judging weight training performance: instructor feedback, student feedback, student comparison, changes noticed outside the gym, personal attraction toward the activity, degree of perceived effort exerted in the workout, performance in workout, feedback from others not in the class, goal setting, muscle development, workout improvement over time, and ease in learning new skills. Results revealed a significant discriminant function analysis for gender, with six information sources entering the stepwise procedure: goal setting, student feedback, learning, effort, improvement, and changes noticed outside the gym differentiated the gender groups. Males relied more than females on student feedback as an information source to judge performance. Alternatively, females used effort, goal setting, improvement, and learning as information sources more than males.

Neural Processing of Gravito-Inertial Cues in Humans. IV. Influence of Visual Rotational Cues During Roll Optokinetic Stimuli

2003 ◽  
Vol 89 (1) ◽  
pp. 390-400 ◽  
Author(s):  
L. H. Zupan ◽  
D. M. Merfeld
Keyword(s):  
Visual Cues ◽  
Gravitational Force ◽  
Sensory Information ◽  
Inertial Force ◽  
Linear Acceleration ◽  
Otolith Organs ◽  
Optokinetic Stimulation ◽  
The Difference ◽  
The Right ◽  
Roll Tilt

Sensory systems often provide ambiguous information. For example, otolith organs measure gravito-inertial force (GIF), the sum of gravitational force and inertial force due to linear acceleration. However, according to Einstein's equivalence principle, a change in gravitational force due to tilt is indistinguishable from a change in inertial force due to translation. Therefore the central nervous system (CNS) must use other sensory cues to distinguish tilt from translation. For example, the CNS might use dynamic visual cues indicating rotation to help determine the orientation of gravity (tilt). This, in turn, might influence the neural processes that estimate linear acceleration, since the CNS might estimate gravity and linear acceleration such that the difference between these estimates matches the measured GIF. Depending on specific sensory information inflow, inaccurate estimates of gravity and linear acceleration can occur. Specifically, we predict that illusory tilt caused by roll optokinetic cues should lead to a horizontal vestibuloocular reflex compensatory for an interaural estimate of linear acceleration, even in the absence of actual linear acceleration. To investigate these predictions, we measured eye movements binocularly using infrared video methods in 17 subjects during and after optokinetic stimulation about the subject's nasooccipital (roll) axis (60°/s, clockwise or counterclockwise). The optokinetic stimulation was applied for 60 s followed by 30 s in darkness. We simultaneously measured subjective roll tilt using a somatosensory bar. Each subject was tested in three different orientations: upright, pitched forward 10°, and pitched backward 10°. Five subjects reported significant subjective roll tilt (>10°) in directions consistent with the direction of the optokinetic stimulation. In addition to torsional optokinetic nystagmus and afternystagmus, we measured a horizontal nystagmus to the right during and following clockwise (CW) stimulation and to the left during and following counterclockwise (CCW) stimulation. These measurements match predictions that subjective tilt in the absence of real tilt should induce a nonzero estimate of interaural linear acceleration and, therefore, a horizontal eye response. Furthermore, as predicted, the horizontal response in the dark was larger for Tilters ( n = 5) than for Non-Tilters ( n= 12).

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