12 results on '"Jamie Johns"'
Search Results
2. DeepWeeds: A Multiclass Weed Species Image Dataset for Deep Learning
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O.P. Kenny, Benjamin Girgenti, Wesley Banks, Mostafa Rahimi Azghadi, Brendan Calvert, James Whinney, Bronson Philippa, Ronald D. White, Jamie Johns, Peter V. Ridd, Jake C. Wood, Alex Olsen, and Dmitry A. Konovalov
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0301 basic medicine ,Crops, Agricultural ,FOS: Computer and information sciences ,Computer Science - Machine Learning ,Boosting (machine learning) ,Computer science ,Weed Control ,Computer Vision and Pattern Recognition (cs.CV) ,Computer Science - Computer Vision and Pattern Recognition ,lcsh:Medicine ,Machine Learning (stat.ML) ,Environment ,Machine learning ,computer.software_genre ,Article ,Machine Learning (cs.LG) ,Machine Learning ,03 medical and health sciences ,0302 clinical medicine ,Deep Learning ,Statistics - Machine Learning ,lcsh:Science ,Multidisciplinary ,business.industry ,Deep learning ,lcsh:R ,Australia ,Agriculture ,Robotics ,Weed control ,030104 developmental biology ,lcsh:Q ,Artificial intelligence ,Neural Networks, Computer ,Rangeland ,business ,Weed ,computer ,030217 neurology & neurosurgery - Abstract
Robotic weed control has seen increased research of late with its potential for boosting productivity in agriculture. Majority of works focus on developing robotics for croplands, ignoring the weed management problems facing rangeland stock farmers. Perhaps the greatest obstacle to widespread uptake of robotic weed control is the robust classification of weed species in their natural environment. The unparalleled successes of deep learning make it an ideal candidate for recognising various weed species in the complex rangeland environment. This work contributes the first large, public, multiclass image dataset of weed species from the Australian rangelands; allowing for the development of robust classification methods to make robotic weed control viable. The DeepWeeds dataset consists of 17,509 labelled images of eight nationally significant weed species native to eight locations across northern Australia. This paper presents a baseline for classification performance on the dataset using the benchmark deep learning models, Inception-v3 and ResNet-50. These models achieved an average classification accuracy of 95.1% and 95.7%, respectively. We also demonstrate real time performance of the ResNet-50 architecture, with an average inference time of 53.4 ms per image. These strong results bode well for future field implementation of robotic weed control methods in the Australian rangelands., Comment: 14 pages, 8 figures, 4 tables
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- 2019
3. Diurnal changes in the efficiency of information transmission at a sensory synapse
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José Moya-Díaz, Ben James, Federico Esposti, Jamie Johnston, and Leon Lagnado
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Science - Abstract
Neuromodulators can adjust how sensory signals are processed. In this study, the authors demonstrate how time of day affects the way information is transmitted in the zebrafish retina.
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- 2022
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4. Barriers to COVID-19 vaccine acceptance to improve messages for vaccine uptake in indigenous populations in the central highlands of Guatemala: a participatory qualitative study
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Nadia Diamond-Smith, Lucía Abascal Miguel, Emily Lopez, Kelly Sanders, Nadine Ann Skinner, Jamie Johnston, Kathryn B Vosburg, Anne Kraemer Diaz, and Magda Silvia Sotz Mux
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Medicine - Abstract
Introduction As of July 2022, a little over one-third of Guatemalans were fully vaccinated. While COVID-19 vaccination rates are not officially reported nationally by racial/ethnic groups, non-governmental organisations and reporters have observed that COVID-19 vaccination rates are especially low among high-risk Indigenous populations. We conducted one of the first studies on COVID-19 vaccine acceptance in Indigenous populations in the Central Highlands of Guatemala, which aimed to better understand the barriers to COVID-19 vaccine uptake and how to improve vaccine promotional campaigns.Methods In November 2021, we conducted eight focus group discussions (FGDs) with 42 Indigenous men and women and 16 in-depth interviews (IDIs) with community health workers, nurses and physicians in Chimaltenango and Sololá. Using a participatory design approach, our qualitative analysis used constant comparative methods to understand the inductive and deductive themes from the FGD and IDI transcripts.Results We found three major overarching barriers to vaccination within the sampled population: (1) a lack of available easily understandable, linguistically appropriate and culturally sensitive COVID-19 vaccine information; (2) vaccine access and supply issues that prevented people from being vaccinated efficiently and quickly; and (3) widespread misinformation and disinformation that prey on people’s fears of the unknown and mistrust of the medical establishment and government.Conclusion When developing COVID-19 vaccine messages, content should be culturally relevant, appropriate for low-literacy populations and in the languages that people prefer to speak. Promotional materials should be in multiple modalities (print, radio and social media) and also have specific Maya cultural references (dress, food and concepts of disease) to ensure messaging connects with intended targets. This study supports the need for more robust research into best practices for communicating about COVID-19 vaccines to marginalised communities globally and suggests that policy makers should invest in targeted local solutions to increase vaccine uptake.
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- 2023
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5. Graded spikes differentially signal neurotransmitter input in cerebrospinal fluid contacting neurons of the mouse spinal cord
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Emily Johnson, Marilyn Clark, Merve Oncul, Andreea Pantiru, Claudia MacLean, Jim Deuchars, Susan A. Deuchars, and Jamie Johnston
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Molecular neuroscience ,Systems neuroscience ,Cellular neuroscience ,Science - Abstract
Summary: The action potential and its all-or-none nature is fundamental to neural communication. Canonically, the action potential is initiated once voltage-activated Na+ channels are activated, and their rapid kinetics of activation and inactivation give rise to the action potential’s all-or-none nature. Here we demonstrate that cerebrospinal fluid contacting neurons (CSFcNs) surrounding the central canal of the mouse spinal cord employ a different strategy. Rather than using voltage-activated Na+ channels to generate binary spikes, CSFcNs use two different types of voltage-activated Ca2+ channel, enabling spikes of different amplitude. T-type Ca2+ channels generate small amplitude spikes, whereas larger amplitude spikes require high voltage-activated Cd2+-sensitive Ca2+ channels. We demonstrate that these different amplitude spikes can signal input from different transmitter systems; purinergic inputs evoke smaller T-type dependent spikes whereas cholinergic inputs evoke larger spikes that do not rely on T-type channels. Different synaptic inputs to CSFcNs can therefore be signaled by the spike amplitude.
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- 2023
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6. Evaluating the impact of a linguistically and culturally tailored social media ad campaign on COVID-19 vaccine uptake among indigenous populations in Guatemala: a pre/post design intervention study
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Nadia Diamond-Smith, Lucía Abascal Miguel, Emily Lopez, Kelly Sanders, Nadine Ann Skinner, Jamie Johnston, Kathryn B Vosburg, and Anne Kraemer Diaz
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Medicine - Abstract
Objectives To evaluate the impact of culturally and linguistically tailored informational videos delivered via social media campaigns on COVID-19 vaccine uptake in Indigenous Maya communities in Guatemala.Methods Our team designed a series of videos utilising community input and evaluated the impact using a pre–post intervention design. In-person preintervention surveys were collected from a sample of respondents in four rural municipalities in Guatemala in March 2022. Facebook, Instagram and browser ads were flooded with COVID-19 vaccine informational videos in Spanish, Kaqchikel and Kiche for 3 weeks. Postintervention surveys were conducted by telephone among the same participants in April 2022. Logistic regression models were used to estimate the OR of COVID-19 vaccine uptake following exposure to the intervention videos.Results Preintervention and postintervention surveys were collected from 1572 participants. The median age was 28 years; 63% (N=998) identified as women, and 36% spoke an Indigenous Mayan language. Twenty-one per cent of participants (N=327) reported watching the intervention content on social media. At baseline, 89% (N=1402) of participants reported having at least one COVID-19 vaccine, compared with 97% (N=1507) in the follow-up. Those who reported watching the videos had 1.78 times the odds (95% CI 1.14 to 2.77) of getting vaccinated after watching the videos compared with those who did not see the videos when adjusted by age, community, sex and language.Conclusion Our findings suggest that culturally and linguistically tailored videos addressing COVID-19 vaccine misinformation deployed over social media can increase vaccinations in a rural, indigenous population in Guatemala, implying that social media content can influence vaccination uptake. Providing accurate, culturally sensitive information in local languages from trusted sources may help increase vaccine uptake in historically marginalised populations.
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- 2022
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7. Design preferences for global scale: a mixed-methods study of 'glocalization' of an animated, video-based health communication intervention
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Maya Adam, Rachel P. Chase, Shannon A. McMahon, Kira-Leigh Kuhnert, Jamie Johnston, Victoria Ward, Charles Prober, and Till Bärnighausen
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Global health ,Health communication ,Health literacy ,Health education ,Human-centered design ,Community health promotion ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Designing health communication interventions for global scaling promotes health literacy and facilitates rapid global health messaging. Limited literature explores preferences for animation prototypes and other content characteristics across participants in different global regions. Prior research underscores an urgent need for health communication interventions that are compelling and accessible across culturally and geographically diverse audiences. This study presents feedback from global learners on animation design preferences and other key considerations for the development of educational video content intended for global adaptation and scaling. Methods We used a mixed-methods, sequential explanatory design, with a qualitative descriptive approach to the analysis of the qualitative data. We recruited participants from an international group of learners enrolled in a massive open online course. Through an online quantitative survey (n = 330), we sought preferences from participants in 73 countries for animation design prototypes to be used in video-based health communication interventions. To learn more about these preferences, we conducted in-depth interviews (n = 20) with participants selected using maximum variation purposive sampling. Results Generally, respondents were willing to accept animation prototypes that were free of cultural and ethnic identifiers and believed these to be preferable for globally scalable health communication videos. Diverse representations of age, gender roles, and family structure were also preferred and felt to support inclusive messaging across cultures and global regions. Familiar-sounding voiceovers using local languages, dialects, and accents were preferred for enhancing local resonance. Across global regions, narratives were highlighted as a compelling approach to facilitating engagement and participants preferred short videos with no more than two or three health messages. Conclusions Our findings suggest that global learners may be willing to accept simplified visuals, designed for broad cross-cultural acceptability, especially if the content is localized in other ways, such as through the use of locally resonating narratives and voiceovers. Diverse, inclusive portrayals of age, gender roles and family structure were preferred.
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- 2021
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8. Digital Education for Health Professionals: An Evidence Map, Conceptual Framework, and Research Agenda
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Lorainne Tudor Car, Selina Poon, Bhone Myint Kyaw, David A Cook, Victoria Ward, Rifat Atun, Azeem Majeed, Jamie Johnston, Rianne M J J van der Kleij, Mariam Molokhia, Florian V Wangenheim, Martin Lupton, Niels Chavannes, Onyema Ajuebor, Charles G Prober, and Josip Car
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundHealth professions education has undergone major changes with the advent and adoption of digital technologies worldwide. ObjectiveThis study aims to map the existing evidence and identify gaps and research priorities to enable robust and relevant research in digital health professions education. MethodsWe searched for systematic reviews on the digital education of practicing and student health care professionals. We searched MEDLINE, Embase, Cochrane Library, Educational Research Information Center, CINAHL, and gray literature sources from January 2014 to July 2020. A total of 2 authors independently screened the studies, extracted the data, and synthesized the findings. We outlined the key characteristics of the included reviews, the quality of the evidence they synthesized, and recommendations for future research. We mapped the empirical findings and research recommendations against the newly developed conceptual framework. ResultsWe identified 77 eligible systematic reviews. All of them included experimental studies and evaluated the effectiveness of digital education interventions in different health care disciplines or different digital education modalities. Most reviews included studies on various digital education modalities (22/77, 29%), virtual reality (19/77, 25%), and online education (10/77, 13%). Most reviews focused on health professions education in general (36/77, 47%), surgery (13/77, 17%), and nursing (11/77, 14%). The reviews mainly assessed participants’ skills (51/77, 66%) and knowledge (49/77, 64%) and included data from high-income countries (53/77, 69%). Our novel conceptual framework of digital health professions education comprises 6 key domains (context, infrastructure, education, learners, research, and quality improvement) and 16 subdomains. Finally, we identified 61 unique questions for future research in these reviews; these mapped to framework domains of education (29/61, 47% recommendations), context (17/61, 28% recommendations), infrastructure (9/61, 15% recommendations), learners (3/61, 5% recommendations), and research (3/61, 5% recommendations). ConclusionsWe identified a large number of research questions regarding digital education, which collectively reflect a diverse and comprehensive research agenda. Our conceptual framework will help educators and researchers plan, develop, and study digital education. More evidence from low- and middle-income countries is needed.
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- 2022
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9. Evaluation of a community-based mobile video breastfeeding intervention in Khayelitsha, South Africa: The Philani MOVIE cluster-randomized controlled trial.
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Maya Adam, Jamie Johnston, Nophiwe Job, Mithilesh Dronavalli, Ingrid Le Roux, Nokwanele Mbewu, Neliswa Mkunqwana, Mark Tomlinson, Shannon A McMahon, Amnesty E LeFevre, Alain Vandormael, Kira-Leigh Kuhnert, Pooja Suri, Jennifer Gates, Bongekile Mabaso, Aarti Porwal, Charles Prober, and Till Bärnighausen
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Medicine - Abstract
BackgroundIn South Africa, breastfeeding promotion is a national health priority. Regular perinatal home visits by community health workers (CHWs) have helped promote exclusive breastfeeding (EBF) in underresourced settings. Innovative, digital approaches including mobile video content have also shown promise, especially as access to mobile technology increases among CHWs. We measured the effects of an animated, mobile video series, the Philani MObile Video Intervention for Exclusive breastfeeding (MOVIE), delivered by a cadre of CHWs ("mentor mothers").Methods and findingsWe conducted a stratified, cluster-randomized controlled trial from November 2018 to March 2020 in Khayelitsha, South Africa. The trial was conducted in collaboration with the Philani Maternal Child Health and Nutrition Trust, a nongovernmental community health organization. We quantified the effect of the MOVIE intervention on EBF at 1 and 5 months (primary outcomes), and on other infant feeding practices and maternal knowledge (secondary outcomes). We randomized 1,502 pregnant women in 84 clusters 1:1 to 2 study arms. Participants' median age was 26 years, 36.9% had completed secondary school, and 18.3% were employed. Mentor mothers in the video intervention arm provided standard-of-care counseling plus the MOVIE intervention; mentor mothers in the control arm provided standard of care only. Within the causal impact evaluation, we nested a mixed-methods performance evaluation measuring mentor mothers' time use and eliciting their subjective experiences through in-depth interviews. At both points of follow-up, we observed no statistically significant differences between the video intervention and the control arm with regard to EBF rates and other infant feeding practices [EBF in the last 24 hours at 1 month: RR 0.93 (95% CI 0.86 to 1.01, P = 0.091); EBF in the last 24 hours at 5 months: RR 0.90 (95% CI 0.77 to 1.04, P = 0.152)]. We observed a small, but significant improvement in maternal knowledge at the 1-month follow-up, but not at the 5-month follow-up. The interpretation of the results from this causal impact evaluation changes when we consider the results of the nested mixed-methods performance evaluation. The mean time spent per home visit was similar across study arms, but the intervention group spent approximately 40% of their visit time viewing videos. The absence of difference in effects on primary and secondary endpoints implies that, for the same time investment, the video intervention was as effective as face-to-face counseling with a mentor mother. The videos were also highly valued by mentor mothers and participants. Study limitations include a high loss to follow-up at 5 months after premature termination of the trial due to the COVID-19 pandemic and changes in mentor mother service demarcations.ConclusionsThis trial measured the effect of a video-based, mobile health (mHealth) intervention, delivered by CHWs during home visits in an underresourced setting. The videos replaced about two-fifths of CHWs' direct engagement time with participants in the intervention arm. The similar outcomes in the 2 study arms thus suggest that the videos were as effective as face-to-face counselling, when CHWs used them to replace a portion of that counselling. Where CHWs are scarce, mHealth video interventions could be a feasible and practical solution, supporting the delivery and scaling of community health promotion services.Trial registrationThe study and its outcomes were registered at clinicaltrials.gov (#NCT03688217) on September 27, 2018.
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- 2021
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10. The Philani MOVIE study: a cluster-randomized controlled trial of a mobile video entertainment-education intervention to promote exclusive breastfeeding in South Africa
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Maya Adam, Mark Tomlinson, Ingrid Le Roux, Amnesty E LeFevre, Shannon A McMahon, Jamie Johnston, Angela Kirton, Nokwanele Mbewu, Stacy-Leigh Strydom, Charles Prober, and Till Bärnighausen
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Mobile health ,Video ,Narrative ,Entertainment-education ,Community-based ,Community health worker ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background In South Africa, rates of exclusive breastfeeding remain low and breastfeeding promotion is a national health priority. Mobile health and narrative entertainment-education are recognized strategies for health promotion. In-home counseling by community health workers (CHWs) is a proven breastfeeding promotion strategy. This protocol outlines a cluster-randomized controlled trial with a nested mixed-methods evaluation of the MObile Video Intervention for Exclusive breastfeeding (MOVIE) program. The evaluation will quantify the causal effect of the MOVIE program and generate a detailed understanding of the context in which the intervention took place and the mechanisms through which it enacted change. Findings from the study will inform the anticipated scale-up of mobile video health interventions in South Africa and the wider sub-Saharan region. Methods We will conduct a stratified cluster-randomized controlled trial in urban communities of the Western Cape, to measure the effect of the MOVIE intervention on exclusive breastfeeding and other infant feeding practices. Eighty-four mentor-mothers (CHWs employed by the Philani Maternal Child Health and Nutrition Trust) will be randomized 1:1 into intervention and control arms, stratified by neighborhood type. Mentor-mothers in the control arm will provide standard of care (SoC) perinatal in-home counseling. Mentor-mothers in the intervention arm will provide SoC plus the MOVIE intervention. At least 1008 pregnant participants will be enrolled in the study and mother-child pairs will be followed until 5 months post-delivery. The primary outcomes of the study are exclusive breastfeeding at 1 and 5 months of age. Secondary outcomes are other infant feeding practices and maternal knowledge. In order to capture human-centered underpinnings of the intervention, we will conduct interviews with stakeholders engaged in the intervention design. To contextualize quantitative findings and understand the mechanisms through which the intervention enacted change, end-line focus groups with mentor-mothers will be conducted. Discussion This trial will be among the first to explore a video-based, entertainment-education intervention delivered by CHWs and created using a community-based, human-centered design approach. As such, it could inform health policy, with regards to both the routine adoption of this intervention and, more broadly, the development of other entertainment-education interventions for health promotion in under-resourced settings. Trial Registration The study and its outcomes were registered at clinicaltrials.gov (#NCT03688217) on September 27th, 2018.
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- 2019
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11. Acceptability of HIV Screening in a Sample of International Students in the United States
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Oluwasola Stephen Ayosanmi, Lorette Oden, Titilope Ayosanmi, Babatunde Y. Alli, Mei Wen, and Jamie Johnson
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Public aspects of medicine ,RA1-1270 - Abstract
Background and Objectives: HIV transmission from persons unaware of their HIV status occurs more commonly than those who are aware of their status. Knowledge of one’s HIV status may encourage preventive behaviors. Anecdotal evidence suggests that many international students may be willing to accept HIV screening, but empirical evidence to support this claim is lacking. We sought to determine the willingness of international students in the United States (US) to accept HIV screening, if offered. Methods: We conducted a cross-sectional study using an online survey of international students at Western Illinois University, USA. The independent variable was the sociodemographic data of our participants; the dependent variable was the acceptance of HIV screening. The covariates were knowledge about HIV and the factors associated with the acceptance of the screening. Descriptive statistics and multivariate analysis were conducted. Results: A total of 185 respondents out of 491 students participated in the online survey. Of these, 107 (57.8%) were males, and 78 (42.8%) were females. Most of the respondents were from Asian countries (64.9%) and African countries (24.9%). The prevalence of acceptance of HIV screening was 74%. Among participants willing to accept screening, if offered, 90% perceived screening would be beneficial to their health. Meanwhile, 83% of those who would refuse the screening were not sexually active. Conclusion and Global Health Implications: Many international students may be interested in getting HIV screening if offered. Awareness of the benefits of HIV screening may influence the decision to screen. Findings may inform further studies that will lead to policy formulations for the health of international students in the US. Key words: • HIV Screening • HIV Acceptability • International Students • College Students Copyright © 2020 Ayosanmi et al. Published by Global Health and Education Projects, Inc. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0) which permits unre-stricted use, distribution, and reproduction in any medium, provided the original work, first published in this journal, is properly cited.
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- 2020
12. General features of the retinal connectome determine the computation of motion anticipation
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Jamie Johnston and Leon Lagnado
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vision ,motion perception ,retinal circuitry ,goldfish ,Medicine ,Science ,Biology (General) ,QH301-705.5 - Abstract
Motion anticipation allows the visual system to compensate for the slow speed of phototransduction so that a moving object can be accurately located. This correction is already present in the signal that ganglion cells send from the retina but the biophysical mechanisms underlying this computation are not known. Here we demonstrate that motion anticipation is computed autonomously within the dendritic tree of each ganglion cell and relies on feedforward inhibition. The passive and non-linear interaction of excitatory and inhibitory synapses enables the somatic voltage to encode the actual position of a moving object instead of its delayed representation. General rather than specific features of the retinal connectome govern this computation: an excess of inhibitory inputs over excitatory, with both being randomly distributed, allows tracking of all directions of motion, while the average distance between inputs determines the object velocities that can be compensated for.
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- 2015
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