Use of Global Optical Flow Rate and Discontinuity Rate Depends on Their Validity as Determinants of Egospeed

Previous research found both discontinuity rate and global optical flow rate contribute to the perception of egospeed but differed in estimates of which source of information dominated. This research examined two methodological differences that may explain the conflicting results: frame rate, and the relative validity of discontinuity rate and flow rate as determinants of egospeed. Observers estimated egospeed perceived during simulations of self-motion. Discontinuity rate and flow rate were manipulated independently by varying velocity and altitude. Frame rates were consistent with Dyre (1997) and the validity of discontinuity rate and flow rate as determinants of egospeed was varied. We found the relative use of discontinuity rate and flow rate was related to the validity of these sources of information. Frame rate was not an important factor. These results suggest the visual system is sensitive to multiple sources of information for perceiving egospeed and adapts to the most optimal source.

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Perception of Accelerating Self-Motion: Global Optical Flow Rate Dominates Discontinuity Rate

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/1071181397041002134 ◽

1997 ◽

Vol 41 (2) ◽

pp. 1333-1337 ◽

Cited By ~ 7

Author(s):

Brian P. Dyre

Keyword(s):

Optical Flow ◽

Flow Rate ◽

Visual Stimuli ◽

Sources Of Information ◽

Minor Influence ◽

Primary Basis ◽

A Minor ◽

And Control ◽

Self Motion

Owen, Wolpert, and Warren (1984) proposed that egospeed may be perceived from global optical flow rate, discontinuity rate, or both. Previous psychophysical research found that both sources of information influence judgments of acceleration and control of egospeed, but that discontinuity rate dominated. However, the validity of these results is questionable due to problems with the visual stimuli used, such as confounding of discontinuity rate with proximal flow rate and low frame rates. The current study examined the relative contributions of global optical flow rate and discontinuity rate to perception of accelerating self-motion with stimuli that lacked these problems. I found that global optical flow rate accounted for 60% of the variability in acceleration judgments, compared with 0.86% for discontinuity rate. This result indicates that discontinuity rate exerts only a minor influence, and global optical flow rate is the primary basis for perception of accelerating self-motion, and hence, egospeed.

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Does Binocular Disparity or Familiar Size Information Override Effects of Relative Size on Judgements of Time to Contact?

The Quarterly Journal of Experimental Psychology Section A ◽

10.1080/02724980443000377 ◽

2005 ◽

Vol 58 (5) ◽

pp. 865-886 ◽

Cited By ~ 24

Author(s):

Patricia R. DeLucia

Keyword(s):

Binocular Disparity ◽

Relative Size ◽

Depth Information ◽

Sources Of Information ◽

Familiar Size ◽

Multiple Sources ◽

Time To Contact ◽

Size Information ◽

Source Of Information ◽

Do So

Previous studies indicate that non-tau sources of depth information, such as pictorial depth cues, can influence judgements of time to contact (TTC). The effect of relative size on such judgements, the size-arrival effect, is particularly robust. However, earlier studies of the size-arrival effect did not include binocular disparity or familiar size information. The effects of these cues on relative TTC judgements were measured. Results suggested that disparity can eliminate the size-arrival effect but that the amount of disparity needed to do so is greater than typical stereoacuity thresholds. In contrast, familiar size eliminated the size-arrival effect even when disparity information was not available. Furthermore, disparity contributed more to performance when familiar size was present than when it was absent. Consistent with previous studies, TTC judgements were influenced by multiple sources of information. The present results suggested further that familiar size is one such source of information and that familiar size moderates the influence of binocular disparity information.

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Confidence Predictions Affect Performance Confidence and Neural Preparation in Perceptual Decision Making.

10.31219/osf.io/mtus8 ◽

2017 ◽

Cited By ~ 1

Author(s):

Anne-Marike Schiffer ◽

Annika Boldt ◽

Florian Waszak ◽

Nick Yeung

Keyword(s):

Decision Making ◽

Color Discrimination ◽

Sources Of Information ◽

Perceptual Decision Making ◽

Multiple Sources ◽

Behavioral Measures ◽

Confidence Judgments ◽

Source Of Information ◽

Preparation And Evaluation ◽

Confidence Estimate

The decisions we make are usually accompanied by a feeling of being wrong or right – a confidence estimate regarding the correctness of our decisions. The questions which information this confidence estimate is based on, and what confidence is used for, have increasingly become a focus of research into decision-making. This research has largely focused on confidence regarding current or past decisions, and successfully identified for example how characteristics of the stimulus affect confidence, and how communicating confidence can affect group decisions. Here, we report two studies which implemented a color-discrimination task which introduced a novel metacognitive measure: predictions of confidence for future perceptual decisions. Using behavioral measures, computational modeling, and EEG, we tested the hypothesis that experience-based confidence predictions are one source of information which affects how confident we are in future decision-making and that one key purpose of confidence is to prepare future encounters of a task. Results from both studies show that participants develop precise confidence predictions informed by confidence experienced in past trials. Notably, our results show a bi-directional link between predicted and experienced (performance) confidence: confidence predictions are not only informed by, but can also modulate performance confidence; this finding supports our recent proposal that confidence judgments are based on multiple sources of information, including expectations. We found further support for this bi-directional link in neural correlates of stimulus-preparation and processing. EEG measures of preparatory neural activity (contingent negative variation; CNV) and evidence accumulation (centro-parietal positivity; CPP) show that predicted confidence affects neural preparation for stimulus processing, supporting the proposal that one purpose of confidence judgments may be to learn about performance for future encounters and prepare accordingly.Taken together, our results suggest that confidence integrates information from various sources, and affects neural processing profoundly. The bi-directional link between performance confidence and predicted confidence suggests that confidence signals are exploited to increase precision in preparation and evaluation of future decisions.

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5. Perception of a 3-D world

Perception: A Very Short Introduction ◽

10.1093/actrade/9780198791003.003.0005 ◽

2017 ◽

pp. 59-83

Author(s):

Brian Rogers

Keyword(s):

Visual System ◽

Optic Flow ◽

Motion Parallax ◽

Sources Of Information ◽

Multiple Sources ◽

Depth Cues ◽

Depth Constancy ◽

Different Sources

The ability to perceive the 3-D world has often been regarded as a task that poses particular problems for the visual system. However, ‘Perception of a 3-D world’ argues that we are particularly fortunate because there are multiple sources of information to tell us about the different aspects of the 3-D structure of objects. It discusses three of these sources of information—perspective, occlusion, and shading—and then explains motion parallax, optic flow, binocular stereopsis, eye vergence and depth constancy, vertical disparities and differential perspective, and primary and secondary depth cues. The effectiveness of these different sources of 3-D information is considered along with how they are all brought together.

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Supporting the Development of Clinical Reasoning of Preprofessional Novices in Dysphagia Management

Seminars in Speech and Language ◽

10.1055/s-0039-1688814 ◽

2019 ◽

Vol 40 (03) ◽

pp. 151-161 ◽

Cited By ~ 1

Author(s):

Sebastian Doeltgen ◽

Stacie Attrill ◽

Joanne Murray

Keyword(s):

Clinical Reasoning ◽

Clinical Decision Making ◽

Management Practice ◽

Clinical Decision ◽

Assessment Process ◽

Evidence Based ◽

Sources Of Information ◽

Multiple Sources ◽

Implicit Processing ◽

Reasoning Skills

AbstractProficient clinical reasoning is a critical skill in high-quality, evidence-based management of swallowing impairment (dysphagia). Clinical reasoning in this area of practice is a cognitively complex process, as it requires synthesis of multiple sources of information that are generated during a thorough, evidence-based assessment process and which are moderated by the patient's individual situations, including their social and demographic circumstances, comorbidities, or other health concerns. A growing body of health and medical literature demonstrates that clinical reasoning skills develop with increasing exposure to clinical cases and that the approaches to clinical reasoning differ between novices and experts. It appears that it is not the amount of knowledge held, but the way it is used, that distinguishes a novice from an experienced clinician. In this article, we review the roles of explicit and implicit processing as well as illness scripts in clinical decision making across the continuum of medical expertise and discuss how they relate to the clinical management of swallowing impairment. We also reflect on how this literature may inform educational curricula that support SLP students in developing preclinical reasoning skills that facilitate their transition to early clinical practice. Specifically, we discuss the role of case-based curricula to assist students to develop a meta-cognitive awareness of the different approaches to clinical reasoning, their own capabilities and preferences, and how and when to apply these in dysphagia management practice.

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Mobility Trends before and after the Pandemic Outbreak: Analyzing the Metropolitan Area of Barcelona through the Lens of Equality and Sustainability

Sustainability ◽

10.3390/su13147908 ◽

2021 ◽

Vol 13 (14) ◽

pp. 7908

Author(s):

Lucía Mejía-Dorantes ◽

Lídia Montero ◽

Jaume Barceló

Keyword(s):

Metropolitan Area ◽

Spatial Arrangement ◽

Individual Characteristics ◽

Sources Of Information ◽

Mobility Patterns ◽

Multiple Sources ◽

Temporal Dimension ◽

Population Groups ◽

Highly Educated ◽

Before And After

The spatial arrangement of a metropolis is of utmost importance to carry out daily activities, which are constrained by space and time. Accessibility is not only shaped by the spatial and temporal dimension, but it is also defined by individual characteristics, such as gender, impairments, or socioeconomic characteristics of the citizens living or commuting in this area. This study analyzes mobility trends and patterns in the metropolitan area of Barcelona before and after the COVID-19 pandemic outbreak, with special emphasis on gender and equality. The study draws on multiple sources of information; however, two main datasets are analyzed: two traditional travel surveys from the transport metropolitan area of Barcelona and two coming from smartphone data. The results show that gender plays a relevant role when analyzing mobility patterns, as already highlighted in other studies, but, after the pandemic outbreak, some population groups were more likely to change their mobility patterns, for example, highly educated population groups and those with higher income. This study also highlights that e-activities may shape new mobility patterns and living conditions for some population segments, but some activities cannot be replaced by IT technologies. For all these reasons, city and transport planning should foster sustainable development policies, which will provide the maximum benefit for society.

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Barriers to identifying and obtaining CME: a national survey of physicians, nurse practitioners and physician assistants

BMC Medical Education ◽

10.1186/s12909-021-02595-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Maureen O’Brien Pott ◽

Anissa S. Blanshan ◽

Kelly M. Huneke ◽

Barbara L. Baasch Thomas ◽

David A. Cook

Keyword(s):

Travel Time ◽

Nurse Practitioners ◽

Professional Associations ◽

Physician Assistants ◽

Age Group ◽

Sources Of Information ◽

Online Search ◽

The Past ◽

Online Tools ◽

Source Of Information

Abstract Background CPD educators and CME providers would benefit from further insight regarding barriers and supports in obtaining CME, including sources of information about CME. To address this gap, we sought to explore challenges that clinicians encounter as they seek CME, and time and monetary support allotted for CME. Methods In August 2018, we surveyed licensed US clinicians (physicians, nurse practitioners, and physician assistants), sampling 100 respondents each of family medicine physicians, internal medicine and hospitalist physicians, medicine specialist physicians, nurse practitioners, and physician assistants (1895 invited, 500 [26.3%] responded). The Internet-based questionnaire addressed barriers to obtaining CME, sources of CME information, and time and monetary support for CME. Results The most often-selected barriers were expense (338/500 [68%]) and travel time (N = 286 [57%]). The source of information about CME activities most commonly selected was online search (N = 348 [70%]). Direct email, professional associations, direct mail, and journals were also each selected by > 50% of respondents. Most respondents reported receiving 1–6 days (N = 301 [60%]) and $1000–$5000 (n = 263 [53%]) per year to use in CME activities. Most (> 70%) also reported no change in time or monetary support over the past 24 months. We found few significant differences in responses across clinician type or age group. In open-ended responses, respondents suggested eight ways to enhance CME: optimize location, reduce cost, publicize effectively, offer more courses and content, allow flexibility, ensure accessibility, make content clinically relevant, and encourage application. Conclusions Clinicians report that expense and travel time are the biggest barriers to CME. Time and money support is limited, and not increasing. Online search and email are the most frequently-used sources of information about CME. Those who organize and market CME should explore options that reduce barriers of time and money, and creatively use online tools to publicize new offerings.

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