scholarly journals Effect of Top-Down Connections in Hierarchical Sparse Coding

2020 ◽  
Vol 32 (11) ◽  
pp. 2279-2309
Author(s):  
Victor Boutin ◽  
Angelo Franciosini ◽  
Franck Ruffier ◽  
Laurent Perrinet
Keyword(s):  
Learning Process ◽  
Sparse Coding ◽  
Prediction Error ◽  
Predictive Coding ◽  
Feedback Mechanism ◽  
Structured Data ◽  
Hard Problem ◽  
Top Down ◽  
Feedback Connection ◽  
The Impact

Hierarchical sparse coding (HSC) is a powerful model to efficiently represent multidimensional, structured data such as images. The simplest solution to solve this computationally hard problem is to decompose it into independent layer-wise subproblems. However, neuroscientific evidence would suggest interconnecting these subproblems as in predictive coding (PC) theory, which adds top-down connections between consecutive layers. In this study, we introduce a new model, 2-layer sparse predictive coding (2L-SPC), to assess the impact of this interlayer feedback connection. In particular, the 2L-SPC is compared with a hierarchical Lasso (Hi-La) network made out of a sequence of independent Lasso layers. The 2L-SPC and a 2-layer Hi-La networks are trained on four different databases and with different sparsity parameters on each layer. First, we show that the overall prediction error generated by 2L-SPC is lower thanks to the feedback mechanism as it transfers prediction error between layers. Second, we demonstrate that the inference stage of the 2L-SPC is faster to converge and generates a refined representation in the second layer compared to the Hi-La model. Third, we show that the 2L-SPC top-down connection accelerates the learning process of the HSC problem. Finally, the analysis of the emerging dictionaries shows that the 2L-SPC features are more generic and present a larger spatial extension.

scholarly journals Dynamic predictive coding across the left fronto-temporal language hierarchy: Evidence from MEG, EEG and fMRI

2021 ◽  
Author(s):  
Lin Wang ◽  
Lotte Schoot ◽  
Trevor Brothers ◽  
Edward Alexander ◽  
Lena Warnke ◽  
...  
Keyword(s):  
Cognitive Processing ◽  
Language Comprehension ◽  
Prediction Error ◽  
Predictive Coding ◽  
Temporal Cortex ◽  
Multiple Time Scales ◽  
Multiple Time ◽  
Top Down ◽  
Levels Of Abstraction ◽  
Successful Resolution

Abstract Predictive coding has been proposed as a unifying theory of brain function. However, few studies have examined this theory during complex cognitive processing across multiple time-scales and levels of abstraction. We used MEG, EEG and fMRI to ask whether dynamic, hierarchical predictive coding can account for the timecourse of evoked activity at multiple cortical levels during language comprehension. Unexpected words produced increased activity in left temporal cortex (lower-level prediction error). Critically, violations of high-precision event predictions produced additional activity within left inferior frontal cortex (higher-level prediction error). Furthermore, the successful resolution of higher-level prediction error led to later feedback to temporal cortex (top-down sharpening), while a failure to resolve these errors led to sustained activity at still lower levels (reanalysis). These findings suggest that fundamental principles of dynamic hierarchical predictive coding –– suppression of prediction error, precision-weighting, delayed top-down sharpening –– can explain the dynamics of neural activity during human language comprehension.

scholarly journals Dynamic predictive coding across the left fronto-temporal language hierarchy: Evidence from MEG, EEG and fMRI

2021 ◽  
Author(s):  
Lin Wang ◽  
Lotte Schoot ◽  
Trevor Brothers ◽  
Edward Alexander ◽  
Lena Warnke ◽  
...  
Keyword(s):  
Cognitive Processing ◽  
Language Comprehension ◽  
Prediction Error ◽  
Predictive Coding ◽  
Temporal Cortex ◽  
Multiple Time Scales ◽  
Multiple Time ◽  
Top Down ◽  
Levels Of Abstraction ◽  
Successful Resolution

AbstractPredictive coding has been proposed as a unifying theory of brain function. However, few studies have examined this theory during complex cognitive processing across multiple time-scales and levels of abstraction. We used MEG, EEG and fMRI to ask whether dynamic, hierarchical predictive coding can account for the timecourse of evoked activity at multiple cortical levels during language comprehension. Unexpected words produced increased activity in left temporal cortex (lower-level prediction error). Critically, violations of high-precision event predictions produced additional activity within left inferior frontal cortex (higher-level prediction error). Furthermore, the successful resolution of higher-level prediction error led to later feedback to temporal cortex (top-down sharpening), while a failure to resolve these errors led to sustained activity at still lower levels (reanalysis). These findings suggest that fundamental principles of dynamic hierarchical predictive coding –– suppression of prediction error, precision-weighting, delayed top-down sharpening –– can explain the dynamics of neural activity during human language comprehension.

The Analyses of Learning Strategies in English as a Second Language: Theoretical Classification and Measurement Test

2020 ◽  
Vol 4 (2) ◽  
pp. 118-129
Author(s):  
Asti Gumartifa ◽  
◽  
Indah Windra Dwie Agustiani
Keyword(s):  
Language Learning ◽  
Learning Outcomes ◽  
Learning Strategies ◽  
Learning Process ◽  
English Learners ◽  
English Language ◽  
Point Of View ◽  
Effective Learning ◽  
The Impact

Gaining English language learning effectively has been discussed all years long. Similarly, Learners have various troubles outcomes in the learning process. Creating a joyful and comfortable situation must be considered by learners. Thus, the implementation of effective learning strategies is certainly necessary for English learners. This descriptive study has two purposes: first, to introduce the classification and characterization of learning strategies such as; memory, cognitive, metacognitive, compensation, social, and affective strategies that are used by learners in the classroom and second, it provides some questionnaires item based on Strategy of Inventory for Language Learning (SILL) version 5.0 that can be used to examine the frequency of students’ learning strategies in the learning process. The summary of this study explains and discusses the researchers’ point of view on the impact of learning outcomes by learning strategies used. Finally, utilizing appropriate learning strategies are certainly beneficial for both teachers and learners to achieve the learning target effectively.

MODIFIKASI MODEL PEMBELAJARAN PROBLEM POSING DENGAN STRATEGI PEMBELAJARAN TUGAS DAN PAKSA

2019 ◽  
Vol 2 ◽  
Author(s):  
Lita Amalia ◽  
Alda Dwiyana Putri ◽  
Alfajri Mairizki Nurfansyah
Keyword(s):  
Student Learning ◽  
Learning Outcomes ◽  
Learning Process ◽  
Learning Strategy ◽  
Student Learning Outcomes ◽  
Learning Model ◽  
Problem Posing ◽  
Reasoning Skills ◽  
The Impact ◽  
Answering Questions

The purpose of this paper is to describe the Problem Posing learning model with Task and Forced Strategy. As for the background of this writing is because of difficulties in understanding the material and also lack of enthusiasm of students in learning the material so that the impact on student learning outcomes is still low. The low student learning outcomes are, of course, many factors, one of which is the problem of applying a learning model that is still teacher-centered, so students tend to be passive. For this reason, the teacher can use the Problem Posing learning model that is modified by the task and force strategy (Task and Forced). Problem Posing learning model is a learning model that requires students to develop their systematic reasoning skills in making questions and answering questions. While the task and force strategy (Task and Forced) is a learning strategy that has little effect on students to complete the task until it is completed and on time to avoid the punishment given by the teacher as a consequence. So that students will be motivated in listening, understanding the material delivered and doing assignments on time. By combining this model and strategy can be a solution so that the learning process becomes quality.

THE USE OF ICT IN ISLAMIC EDUCATION (PAI) LEARNING AT SCHOOL: A Case Study on Integrated Islamic High School (SMA-IT) Ummul Quro Bogor

2020 ◽  
Author(s):  
Farida Hanun
Keyword(s):  
High School ◽  
Learning Process ◽  
Research Method ◽  
Qualitative Approach ◽  
Learning Systems ◽  
Government Support ◽  
Islamic Education ◽  
Inhibiting Factors ◽  
The Impact

This study aims to obtain a description related to the learning of PAI by using ICT and how the impact of the use of ICT on PAI learning systems in the classroom. The research method uses a qualitative approach in the integrated Islamic high school Ummul Quro Bogor, West Java. The results showed that a) there were four stages of using ICT in the learning process, namely; emerging, applying, integrating dan transforming. PAI teachers are already at the integrating stage. In other words, ICT has been integrated into the PAI learning curriculum. b) supporting factors for the use of ICT are the existence of ICT support facilities, the availability of qualified educators, the commitment of the school to implement ICT in every PAI learning. c) Inhibiting factors in the use of ICT are aspects of financing ICT facilities require a large budget. Some elderly teachers have difficulty using ICT in the learning process. Besides, the internet network is unstable. d) The impact of the use of ICT is very significant on PAI learning process. e) the existence of ICT devices not only as a support but already as an important component in the education system. The research led to the recommendation of the need for government support in the form of concern for ICT in terms of policies, facilities, workforce, budget, and organizing training in the use of ICT for PAI teachers to improve their professionalism. Therefore, further research is suggested regarding the effectiveness of the use of ICT in the learning process of PAI.

scholarly journals The Geriatric Medication Game to Raise Community Pharmacists’ Awareness on Older Adults’ Day-to-Day Challenges

2021 ◽  
pp. 1-6
Author(s):  
Aisha F. Badr
Keyword(s):  
Older Adults ◽  
Saudi Arabia ◽  
Learning Process ◽  
Community Pharmacists ◽  
The Elderly ◽  
Learning Activity ◽  
Simulation Games ◽  
Self Reflection ◽  
Satisfaction Rate ◽  
The Impact

<b><i>Introduction:</i></b> In Saudi Arabia; it is estimated that the elderly (aged 60 and above) would reach up to (22.9%) by 2050, compared to (5.6%) in 2017. Simulation games have proven to be a useful and effective method of education in pharmacy schools, as it actively involves participants in the learning process. The objective of this study was to examine the impact of the modified geriatric medication game on community pharmacists’ awareness and attitudes toward older adults with common disabilities. <b><i>Methods:</i></b> A modified geriatric medication game was adopted to stimulate both physical and sensory disabilities in older adults. A total of 9 community pharmacists were gathered in 1 room and were asked to play 2 scenarios each. Self-reflection was assessed and ground theories were analyzed. <b><i>Results:</i></b> All pharmacists felt frustration and anger playing the game (100%), followed by becoming more aware of the extra time and guidance needed with older adults and realized how disabling chronic diseases could be, and felt they needed to improve common perceived attitude towards the elderly (88.89%). Pharmacists also felt empathy, sympathy, and compassion towards this population, needed improvement of common perceived attitude towards older adults, and felt the need to double check with older adults if they have any disabilities before counseling (77.78%). Finally, over half pharmacists (55.5%) wished they had more training on geriatrics during pharmacy school and the need for further review of Beer’s criteria. All pharmacists were satisfied with the game and recommended it to all community pharmacists. <b><i>Conclusion:</i></b> Simulation games are a great way to strengthen awareness and change practice accordingly. Pharmacists improved their awareness and attitude towards the elderly and reported a positive perceived value of this learning activity; with a 100% satisfaction rate. Adding a geriatric course with simulation component is recommended for better geriatric care.

scholarly journals 152. Applying A Difference-in-Difference Analysis to Assess Effect of Antimicrobial Stewardship Strategies on Changes in Antimicrobial Use

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S86-S86
Author(s):  
Ann F Chou ◽  
Yue Zhang ◽  
Makoto M Jones ◽  
Christopher J Graber ◽  
Matthew B Goetz ◽  
...  
Keyword(s):  
Antimicrobial Stewardship ◽  
Clinical Pharmacist ◽  
Antibiotic Use ◽  
Feedback Mechanism ◽  
Health Care Facilities ◽  
Antimicrobial Use ◽  
Time Points ◽  
The Difference ◽  
The Impact ◽  
Over Time

Abstract Background About 30–50% of inpatient antimicrobial therapy is sub-optimal. Health care facilities have utilized various antimicrobial stewardship (AS) strategies to optimize appropriate antimicrobial use, improve health outcomes, and promote patient safety. However, little evidence exists to assess relationships between AS strategies and antimicrobial use. This study examined the impact of changes in AS strategies on antimicrobial use over time. Methods This study used data from the Veterans Affairs (VA) Healthcare Analysis & Informatics Group (HAIG) AS survey, administered at 130 VA facilities in 2012 and 2015, and antimicrobial utilization from VA Corporate Data Warehouse. Four AS strategies were examined: having an AS team, feedback mechanism on antimicrobial use, infectious diseases (ID) attending physicians, and clinical pharmacist on wards. Change in AS strategies were computed by taking the difference in the presence of a given strategy in a facility between 2012–2015. The outcome was the difference between antimicrobial use per 1000 patient days in 2012–2013 and 2015–2016. Employing multiple regression analysis, changes in antimicrobial use was estimated as a function of changes in AS strategies, controlling for ID human resources in and organizational complexity. Results Of the 4 strategies, only change in availability of AS teams had an impact on antimicrobial use. Compared to facilities with no AS teams at both time points, antibiotic use decreased by 63.9 uses per 1000 patient days in facilities that did not have a AS team in 2012 but implemented one in 2015 (p=0.0183). Facilities that had an AS team at both time points decreased use by 62.2 per 1000 patient days (p=0.0324). Conclusion The findings showed that AS teams reduced inpatient antibiotic use over time. While changes in having feedback on antimicrobial use and clinical pharmacist on wards showed reduced antimicrobial use between 2012–2015, the differences were not statistically significant. These strategies may already be a part of a comprehensive AS program and employed by AS teams. In further development of stewardship programs within healthcare organizations, the association between AS teams and antibiotic use should inform program design and implementation. Disclosures All Authors: No reported disclosures

#3083 Fibromyalgia and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS): an interoceptive predictive coding model of pain and fatigue expression

2021 ◽  
Vol 92 (8) ◽  
pp. A3.3-A4
Author(s):  
Harriet Sharp ◽  
Kristy Themelis ◽  
Marisa Amato ◽  
Andrew Barritt ◽  
Kevin Davies ◽  
...  
Keyword(s):  
Prediction Error ◽  
Predictive Coding ◽  
Chronic Fatigue ◽  
Self Report ◽  
Subjective Experiences ◽  
Double Blind ◽  
Pain Thresholds ◽  
Pressure Pain Thresholds ◽  
Interoceptive Accuracy ◽  
Bodily States

IntroductionThe aetiology and pathophysiology of fibromyalgia and ME/CFS are poorly characterised but altered inflammatory, autonomic and interoceptive processes have been implicated. Interoception has been conceptualised as a predictive coding process; where top-down prediction signals compare to bottom-up afferents, resulting in prediction error signals indicating mismatch between expected and actual bodily states. Chronic dyshomeostasis and elevated interoceptive prediction error signals have been theorised to contribute to the expression of pain and fatigue in fibromyalgia and ME/CFS.Objectives/AimsTo investigate how altered interoception and prediction error relates to baseline expression of pain and fatigue in fibromyalgia and ME/CFS and in response to an inflammatory challenge.MethodsSixty-five patients with fibromyalgia and/or ME/CFS diagnosis and 26 matched controls underwent baseline assessment: self-report questionnaires assessing subjective pain and fatigue and objective measurements of pressure-pain thresholds. Participants received injections of typhoid (inflammatory challenge) or saline (placebo) in a randomised, double-blind, crossover design, then completed heartbeat tracking task (assessing interoceptive accuracy). Porges Body Questionnaire assessed interoceptive sensibility. Interoceptive prediction error (IPE) was calculated as discrepancy between objective accuracy and subjective sensibility.ResultsPatients with fibromyalgia and ME/CFS had significantly higher IPE (suggesting tendency to over-estimate interoceptive ability) and interoceptive sensibility, despite no differences in interoceptive accuracy. IPE and sensibility correlated positively with all self-report fatigue and pain measures, and negatively with pain thresholds. Following inflammatory challenge, IPE correlated negatively with the mismatch between subjective and objective measures of pain induced by inflammation.ConclusionsThis is the first study to reveal altered interoception processes in patients with fibromyalgia and ME/CFS, who are known to have dysregulated autonomic function. Notably, we found elevated IPE in patients, correlating with their subjective experiences of pain and fatigue. We hypothesise a predictive coding model, where mismatch between expected and actual internal bodily states (linked to autonomic dysregulation) results in prediction error signalling which could be metacognitively interpreted as chronic pain and fatigue. Our results demonstrate potential for further exploration of interoceptive processing in patients with fibromyalgia and ME/CFS, aiding understanding of these poorly defined conditions and providing potential new targets for diagnostic and therapeutic intervention.

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