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1.
Proc Natl Acad Sci U S A ; 121(6): e2308215121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38294944

RESUMO

In various biological systems, information from many noisy molecular receptors must be integrated into a collective response. A striking example is the thermal imaging organ of pit vipers. Single nerve fibers in the organ reliably respond to milli-Kelvin (mK) temperature increases, a thousand times more sensitive than their molecular sensors, thermo-transient receptor potential (TRP) ion channels. Here, we propose a mechanism for the integration of this molecular information. In our model, amplification arises due to proximity to a dynamical bifurcation, separating a regime with frequent and regular action potentials (APs), from a regime where APs are irregular and infrequent. Near the transition, AP frequency can have an extremely sharp dependence on temperature, naturally accounting for the thousand-fold amplification. Furthermore, close to the bifurcation, most of the information about temperature available in the TRP channels' kinetics can be read out from the times between consecutive APs even in the presence of readout noise. A key model prediction is that the coefficient of variation in the distribution of interspike times decreases with AP frequency, and quantitative comparison with experiments indeed suggests that nerve fibers of snakes are located very close to the bifurcation. While proximity to such bifurcation points typically requires fine-tuning of parameters, we propose that having feedback act from the order parameter (AP frequency) onto the control parameter robustly maintains the system in the vicinity of the bifurcation. This robustness suggests that similar feedback mechanisms might be found in other sensory systems which also need to detect tiny signals in a varying environment.


Assuntos
Crotalinae , Canais de Potencial de Receptor Transitório , Animais , Serpentes/fisiologia , Temperatura , Potenciais de Ação
2.
Biometrics ; 80(3)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39248121

RESUMO

Recent years have witnessed a rise in the popularity of information integration without sharing of raw data. By leveraging and incorporating summary information from external sources, internal studies can achieve enhanced estimation efficiency and prediction accuracy. However, a noteworthy challenge in utilizing summary-level information is accommodating the inherent heterogeneity across diverse data sources. In this study, we delve into the issue of prior probability shift between two cohorts, wherein the difference of two data distributions depends on the outcome. We introduce a novel semi-parametric constrained optimization-based approach to integrate information within this framework, which has not been extensively explored in existing literature. Our proposed method tackles the prior probability shift by introducing the outcome-dependent selection function and effectively addresses the estimation uncertainty associated with summary information from the external source. Our approach facilitates valid inference even in the absence of a known variance-covariance estimate from the external source. Through extensive simulation studies, we observe the superiority of our method over existing ones, showcasing minimal estimation bias and reduced variance for both binary and continuous outcomes. We further demonstrate the utility of our method through its application in investigating risk factors related to essential hypertension, where the reduced estimation variability is observed after integrating summary information from an external data.


Assuntos
Simulação por Computador , Hipertensão Essencial , Probabilidade , Humanos , Modelos Estatísticos , Fatores de Risco , Hipertensão , Interpretação Estatística de Dados , Biometria/métodos
3.
Brain Cogn ; 178: 106166, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38733655

RESUMO

Although most category learning studies use feedback for training, little attention has been paid to how individuals utilize feedback implemented as gains or losses during categorization. We compared skilled categorization under three different conditions: Gain (earn points for correct answers), Gain and Loss (earn points for correct answers and lose points for wrong answers) and Correct or Wrong (accuracy feedback only). We also manipulated difficulty and point value, with near boundary stimuli having the highest number of points to win or lose, and stimuli far from the boundary having the lowest point value. We found that the tail of the caudate was sensitive to feedback condition, with highest activity when both Gain and Loss feedback were present and least activity when only Gain or accuracy feedback was present. We also found that activity across the caudate was affected by distance from the decision bound, with greatest activity for the near boundary high value stimuli, and lowest for far low value stimuli. Overall these results indicate that the tail of the caudate is sensitive not only to positive rewards but also to loss and punishment, consistent with recent animal research finding tail of the caudate activity in aversive learning.


Assuntos
Núcleo Caudado , Imageamento por Ressonância Magnética , Humanos , Núcleo Caudado/fisiologia , Masculino , Feminino , Adulto , Adulto Jovem , Recompensa , Retroalimentação Psicológica/fisiologia , Mapeamento Encefálico/métodos , Formação de Conceito/fisiologia
4.
Hum Factors ; 65(7): 1473-1490, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-34579591

RESUMO

OBJECTIVE: Examine the extent to which increasing information integration across displays in a simulated submarine command and control room can reduce operator workload, improve operator situation awareness, and improve team performance. BACKGROUND: In control rooms, the volume and number of sources of information are increasing, with the potential to overwhelm operator cognitive capacity. It is proposed that by distributing information to maximize relevance to each operator role (increasing information integration), it is possible to not only reduce operator workload but also improve situation awareness and team performance. METHOD: Sixteen teams of six novice participants were trained to work together to combine data from multiple sensor displays to build a tactical picture of surrounding contacts at sea. The extent that data from one display were available to operators at other displays was manipulated (information integration) between teams. Team performance was assessed as the accuracy of the generated tactical picture. RESULTS: Teams built a more accurate tactical picture, and individual team members had better situation awareness and lower workload, when provided with high compared with low information integration. CONCLUSION: A human-centered design approach to integrating information in command and control settings can result in lower workload, and enhanced situation awareness and team performance. APPLICATION: The design of modern command and control rooms, in which operators must fuse increasing volumes of complex data from displays, may benefit from higher information integration based on a human-centered design philosophy, and a fundamental understanding of the cognitive work that is carried out by operators.


Assuntos
Análise e Desempenho de Tarefas , Carga de Trabalho , Humanos , Carga de Trabalho/psicologia , Conscientização , Simulação por Computador , Navios
5.
Entropy (Basel) ; 25(9)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37761627

RESUMO

It has been shown that three-dimensional self-assembled multicellular structures derived from human pluripotent stem cells show electrical activity similar to EEG. More recently, neurons were successfully embedded in digital game worlds. The biologically inspired neural network (BNN), expressing human cortical cells, was able to show internal modification and learn the task at hand (predicting the trajectory of a digital ball while moving a digital paddle). In other words, the system allowed to read motor information and write sensory data into cell cultures. In this article, we discuss Neural Correlates of Consciousness (NCC) theories, and their capacity to predict or even allow for consciousness in a BNN. We found that Information Integration Theory (IIT) is the only NCC that offers the possibility for a BNN to show consciousness, since the Φ value in the BNN is >0. In other words, the recording of real-time neural activity responding to environmental stimuli. IIT argues that any system capable of integrating information will have some degree of phenomenal consciousness. We argue that the pattern of activity appearing in the BNN, with increased density of sensory information leading to better performance, implies that the BNN could be conscious. This may have profound implications from a psychological, philosophical, and ethical perspective.

6.
Brain ; 144(5): 1603-1614, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-33829262

RESUMO

An abnormality in inference, resulting in distorted internal models of the world, has been argued to be a common mechanism underlying the heterogeneous psychopathology in schizophrenia. However, findings have been mixed as to wherein the abnormality lies and have typically failed to find convincing relations to symptoms. The limited and inconsistent findings may have been due to methodological limitations of the experimental design, such as conflating other factors (e.g. comprehension) with the inferential process of interest, and a failure to adequately assess and model the key aspects of the inferential process. Here, we investigated probabilistic inference based on multiple sources of information using a new digital version of the beads task, framed in a social context. Thirty-five patients with schizophrenia or schizoaffective disorder with a wide range of symptoms and 40 matched healthy control subjects performed the task, where they guessed the colour of the next marble drawn from a jar based on a sample from the jar as well as the choices and the expressed confidence of four people, each with their own independent sample (which was hidden from participant view). We relied on theoretically motivated computational models to assess which model best captured the inferential process and investigated whether it could serve as a mechanistic model for both psychotic and negative symptoms. We found that 'circular inference' best described the inference process, where patients over-weighed and overcounted direct experience and under-weighed information from others. Crucially, overcounting of direct experience was uniquely associated with most psychotic and negative symptoms. In addition, patients with worse social cognitive function had more difficulties using others' confidence to inform their choices. This difficulty was related to worse real-world functioning. The findings could not be easily ascribed to differences in working memory, executive function, intelligence or antipsychotic medication. These results suggest hallucinations, delusions and negative symptoms could stem from a common underlying abnormality in inference, where directly experienced information is assigned an unreasonable weight and taken into account multiple times. By this, even unreliable first-hand experiences may gain disproportionate significance. The effect could lead to false perceptions (hallucinations), false beliefs (delusions) and deviant social behaviour (e.g. loss of interest in others, bizarre and inappropriate behaviour). This may be particularly problematic for patients with social cognitive deficits, as they may fail to make use of corrective information from others, ultimately leading to worse social functioning.


Assuntos
Psicologia do Esquizofrênico , Comportamento Social , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia
7.
Conscious Cogn ; 104: 103383, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35963081

RESUMO

The most widely endorsed philosophical and scientific theories of consciousness assume that it contributes a single functional capacity to an organism's information processing toolkit. However, conscious processes are a heterogeneous class of psychological phenomena supported by a variety of neurobiological mechanisms. This suggests a plurality of functional contributions of consciousness (FCCs), in the sense that conscious experience facilitates different functional capacities in different psychological domains. In this paper, I first develop a general methodological framework for isolating the psychological functions that are associated with conscious experience. I then use this to show that the leading accounts-Global Workspace Theories, Higher Order Thought Theory and Information Integration Theory-all fail to acknowledge this functional pluralism, which limits their applicability as theories of consciousness.


Assuntos
Cognição , Estado de Consciência , Humanos
8.
Entropy (Basel) ; 24(8)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36010760

RESUMO

Fatigue driving is one of the major factors that leads to traffic accidents. Long-term monotonous driving can easily cause a decrease in the driver's attention and vigilance, manifesting a fatigue effect. This paper proposes a means of revealing the effects of driving fatigue on the brain's information processing abilities, from the aspect of a directed brain network based on electroencephalogram (EEG) source signals. Based on current source density (CSD) data derived from EEG signals using source analysis, a directed brain network for fatigue driving was constructed by using a directed transfer function. As driving time increased, the average clustering coefficient as well as the average path length gradually increased; meanwhile, global efficiency gradually decreased for most rhythms, suggesting that deep driving fatigue enhances the brain's local information integration abilities while weakening its global abilities. Furthermore, causal flow analysis showed electrodes with significant differences between the awake state and the driving fatigue state, which were mainly distributed in several areas of the anterior and posterior regions, especially under the theta rhythm. It was also found that the ability of the anterior regions to receive information from the posterior regions became significantly worse in the driving fatigue state. These findings may provide a theoretical basis for revealing the underlying neural mechanisms of driving fatigue.

9.
Eur J Neurosci ; 54(9): 7141-7151, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34550613

RESUMO

Spatial integration during the brain's cognitive activity prompts changes in energy used by different neuroglial populations. Nevertheless, the organisation of such integration in 3D -brain activity remains undescribed from a quantitative standpoint. In response, we applied a cross-correlation between brain activity and integrative models, which yielded a deeper understanding of information integration in functional brain mapping. We analysed four datasets obtained via fundamentally different neuroimaging techniques (functional magnetic resonance imaging [fMRI] and positron emission tomography [PET]) and found that models of spatial integration with an increasing input to each step of integration were significantly more correlated with brain activity than models with a constant input to each step of integration. In addition, marking the voxels with the maximal correlation, we found exceptionally high intersubject consistency with the initial brain activity at the peaks. Our method demonstrated for the first time that the network of peaks of brain activity is organised strictly according to the models of spatial integration independent of neuroimaging techniques. The highest correlation with models integrating an increasing at each step input suggests that brain activity reflects a network of integrative processes where the results of integration in some neuroglial populations serve as an input to other neuroglial populations.


Assuntos
Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Neuroimagem
10.
Cereb Cortex ; 30(8): 4563-4580, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32219312

RESUMO

At any given moment, we experience a perceptual scene as a single whole and yet we may distinguish a variety of objects within it. This phenomenon instantiates two properties of conscious perception: integration and differentiation. Integration is the property of experiencing a collection of objects as a unitary percept and differentiation is the property of experiencing these objects as distinct from each other. Here, we evaluated the neural information dynamics underlying integration and differentiation of perceptual contents during bistable perception. Participants listened to a sequence of tones (auditory bistable stimuli) experienced either as a single stream (perceptual integration) or as two parallel streams (perceptual differentiation) of sounds. We computed neurophysiological indices of information integration and information differentiation with electroencephalographic and intracranial recordings. When perceptual alternations were endogenously driven, the integrated percept was associated with an increase in neural information integration and a decrease in neural differentiation across frontoparietal regions, whereas the opposite pattern was observed for the differentiated percept. However, when perception was exogenously driven by a change in the sound stream (no bistability), neural oscillatory power distinguished between percepts but information measures did not. We demonstrate that perceptual integration and differentiation can be mapped to theoretically motivated neural information signatures, suggesting a direct relationship between phenomenology and neurophysiology.


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Estimulação Acústica , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
11.
J Exp Child Psychol ; 210: 105198, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34098166

RESUMO

A key question in the developmental sciences is whether developmental differences are quantitative or qualitative. For example, does age increase the speed in processing a task (quantitative differences) or does age affect the way a task is processed (qualitative differences)? Until now, findings in the domain of decision making have been based on the assumption that developmental differences are either quantitative or qualitative. In the current study, we took a different approach in which we tested whether development is best described as being quantitative or qualitative. We administered a judgment version and a choice version of a decision-making task to a developmental sample (njudgment = 109 and nchoice = 137; Mage = 12.5 years, age range = 9-18). The task, the so-called Gambling Machine Task, required decisions between two options characterized by constant gains and probabilistic losses; these characteristics were known beforehand and thus did not need to be learned from experience. Data were analyzed by comparing the fit of quantitative and qualitative latent variable models, so-called multiple indicator multiple cause (MIMIC) models. Results indicated that individual differences in both judgment and choice tasks were quantitative and pertained to individual differences in "consideration of gains," that is, to what extent decisions were guided by gains. These differences were affected by age in the judgment version, but not in the choice version, of the task. We discuss implications for theories of decision making and discuss potential limitations and extensions. We also argue that the MIMIC approach is useful in other domains, for example, to test quantitative versus qualitative development of categorization, reasoning, math, and memory.


Assuntos
Tomada de Decisões , Jogo de Azar , Adolescente , Criança , Humanos , Julgamento , Matemática , Resolução de Problemas
12.
Sensors (Basel) ; 20(12)2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32560463

RESUMO

Integration of multiple, heterogeneous sensors is a challenging problem across a range of applications. Prominent among these are multi-target tracking, where one must combine observations from different sensor types in a meaningful and efficient way to track multiple targets. Because different sensors have differing error models, we seek a theoretically justified quantification of the agreement among ensembles of sensors, both overall for a sensor collection, and also at a fine-grained level specifying pairwise and multi-way interactions among sensors. We demonstrate that the theory of mathematical sheaves provides a unified answer to this need, supporting both quantitative and qualitative data. Furthermore, the theory provides algorithms to globalize data across the network of deployed sensors, and to diagnose issues when the data do not globalize cleanly. We demonstrate and illustrate the utility of sheaf-based tracking models based on experimental data of a wild population of black bears in Asheville, North Carolina. A measurement model involving four sensors deployed among the bears and the team of scientists charged with tracking their location is deployed. This provides a sheaf-based integration model which is small enough to fully interpret, but of sufficient complexity to demonstrate the sheaf's ability to recover a holistic picture of the locations and behaviors of both individual bears and the bear-human tracking system. A statistical approach was developed in parallel for comparison, a dynamic linear model which was estimated using a Kalman filter. This approach also recovered bear and human locations and sensor accuracies. When the observations are normalized into a common coordinate system, the structure of the dynamic linear observation model recapitulates the structure of the sheaf model, demonstrating the canonicity of the sheaf-based approach. However, when the observations are not so normalized, the sheaf model still remains valid.

13.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(3): 221-225, 2020 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-32621429

RESUMO

OBJECTIVE: This study introduces the feasibility study experience of intensive care clinical information management system in order to provide reference for the construction of intensive care clinical information management system in other hospitals. METHODS: Four kinds of mainstream intensive care clinical information management system software were used to evaluate the implementation effect of each software such as equipment integration, information integration and application function module, so as to explore the construction scheme of intensive care clinical information management system. RESULTS: The optimized construction scheme and comprehensive feasibility study report of intensive care clinical information management system were formed, which provided an objective basis for the final scheme design, demonstration, procurement and decision-making of the hospital. CONCLUSIONS: The trial and feasibility study of intensive care clinical information management system contribute to optimize the construction scheme.


Assuntos
Cuidados Críticos , Unidades de Terapia Intensiva , Estudos de Viabilidade , Humanos , Gestão da Informação , Software
14.
J Exp Child Psychol ; 188: 104673, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31430573

RESUMO

Adults outperform children on category learning that requires selective attention to individual dimensions (rule-based categories) due to their more highly developed working memory abilities, but much less is known about developmental differences in learning categories that require integration across multiple dimensions (information-integration categories). The current study investigated auditory information-integration category learning in 5- to 7-year-old children (n = 34) and 18- to 25-year-old adults (n = 35). Adults generally outperformed children during learning. However, some children learned the categories well and used strategies similar to those of adults, as assessed through decision-bound computational models. The results demonstrate that information-integration learning ability continues to develop throughout at least middle childhood. These results have implications for the development of mechanisms that contribute to speech category learning.


Assuntos
Formação de Conceito/fisiologia , Aprendizagem/fisiologia , Memória de Curto Prazo/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Inteligência/fisiologia , Masculino , Adulto Jovem
15.
Proc Natl Acad Sci U S A ; 113(50): 14444-14449, 2016 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-27911805

RESUMO

We often engage in two concurrent but unrelated activities, such as driving on a quiet road while listening to the radio. When we do so, does our brain split into functionally distinct entities? To address this question, we imaged brain activity with fMRI in experienced drivers engaged in a driving simulator while listening either to global positioning system instructions (integrated task) or to a radio show (split task). We found that, compared with the integrated task, the split task was characterized by reduced multivariate functional connectivity between the driving and listening networks. Furthermore, the integrated information content of the two networks, predicting their joint dynamics above and beyond their independent dynamics, was high in the integrated task and zero in the split task. Finally, individual subjects' ability to switch between high and low information integration predicted their driving performance across integrated and split tasks. This study raises the possibility that under certain conditions of daily life, a single brain may support two independent functional streams, a "functional split brain" similar to what is observed in patients with an anatomical split.


Assuntos
Condução de Veículo/psicologia , Lateralidade Funcional/fisiologia , Comportamento Multitarefa/fisiologia , Estimulação Acústica , Adulto , Simulação por Computador , Neuroimagem Funcional , Sistemas de Informação Geográfica , Humanos , Imageamento por Ressonância Magnética , Masculino , Modelos Neurológicos , Modelos Psicológicos , Análise Multivariada , Rede Nervosa/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
16.
Cogn Emot ; 33(2): 305-317, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29553877

RESUMO

In this research, we investigated whether appraisals of faces follow distinct rules of information integration under arousing versus non-arousing conditions. Support for this prediction was found in four experiments in which participants observed angry (and fearful) faces that were presented with a direct versus an averted gaze (Experiments 1a, b), on a red versus a grey background (Experiment 2), and after performing a motor exercise versus no exercise (Experiment 3). Under arousing conditions, participants' appraisals of faces reflected summation (i.e. extremely negative encounters were strengthened by moderately negative encounters) whereas, under non-arousing conditions, appraisals did not reflect summation (i.e. extremely negative encounters were weakened by moderately negative encounters) and could instead be accounted for by three alternative rules of information integration based on averaging, mere exposure, or the number of strong stimuli.


Assuntos
Ira/fisiologia , Nível de Alerta/fisiologia , Expressão Facial , Medo/psicologia , Fixação Ocular/fisiologia , Estimulação Luminosa/métodos , Adulto , Exercício Físico/psicologia , Medo/fisiologia , Feminino , Humanos , Masculino , Estudantes/psicologia , Adulto Jovem
17.
Sensors (Basel) ; 20(1)2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878091

RESUMO

Object recognition, which can be used in processes such as reconstruction of the environment map or the intelligent navigation of vehicles, is a necessary task in smart city environments. In this paper, we propose an architecture that integrates heterogeneously distributed information to recognize objects in intelligent environments. The architecture is based on the IoT/Industry 4.0 model to interconnect the devices, which are called smart resources. smart resources can process local sensor data and offer information to other devices as a service. These other devices can be located in the same operating range (the edge), in the same intranet (the fog), or on the Internet (the cloud). smart resources must have an intelligent layer in order to be able to process the information. A system with two smart resources equipped with different image sensors is implemented to validate the architecture. Our experiments show that the integration of information increases the certainty in the recognition of objects by 2-4%. Consequently, in intelligent environments, it seems appropriate to provide the devices with not only intelligence, but also capabilities to collaborate closely with other devices.

18.
Hum Factors ; 61(2): 169-190, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30335518

RESUMO

OBJECTIVE: To investigate whether manipulating the format of an automated decision aid's cues can improve participants' information integration strategies in a signal detection task. BACKGROUND: Automation-aided decision making is often suboptimal, falling well short of statistically ideal levels. The choice of format in which the cues from the aid are displayed may help users to better understand and integrate the aid's judgments with their own. METHOD: Participants performed a signal detection task that asked them to classify random dot images as either blue or orange dominant. They made their judgments either unaided or with assistance from a 93% reliable automated decision aid. The aid provided a binary judgment, along with an estimate of signal strength in the form of either a raw value, a likelihood ratio, or a confidence rating (Experiments 1 and 2) or a binary judgment along with either a verbal or verbal-visuospatial expression of confidence (Experiment 3). Aided sensitivity was benchmarked to the predictions of various statistical models of collaborative decision making. RESULTS AND CONCLUSION: Aided performance was suboptimal, matching the predictions of some of the least efficient models. Most importantly, performance was similar across cue formats. APPLICATION: Results indicate that changes to the format in which cues from a signal detection aid are rendered are unlikely to dramatically improve the efficiency of automation-aided decision making.


Assuntos
Automação , Percepção de Cores/fisiologia , Sinais (Psicologia) , Tomada de Decisões/fisiologia , Técnicas de Apoio para a Decisão , Reconhecimento Visual de Modelos/fisiologia , Detecção de Sinal Psicológico/fisiologia , Adulto , Humanos
19.
J Sci Food Agric ; 99(8): 3941-3949, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30701560

RESUMO

BACKGROUND: The shrivelled defect of walnuts has a serious effect on walnut quality and is a common internal defect of in-shell walnuts. However, only depending on a single detection technique such as machine vision to detect in-shell shrivelled walnuts is challenging. Meanwhile, the threshold has a great impact on the accuracy of the discrimination analysis. Therefore, the golden-section was used to search the optimal discrimination threshold and the information integration of force sensing and machine vision was used to identify the shrivelled walnut and the sound walnut. RESULTS: A discrimination model for in-shell shrivelled walnut based on information integration of force sensing and machine vision was built. The optimal threshold was determined as 0.3464 by the golden-section method, and the optimal threshold was used to discriminate the in-shell shrivelled walnut and the sound walnut. The discriminant accuracy of in-shell shrivelled and sound walnuts were 96.97% and 85.29%, respectively, and the total discriminant accuracy reached 93.00% based on the discrimination model. CONCLUSION: The results indicated the information integration of force sensing and machine vision based on the golden-section search optimal discrimination threshold is a potential method to discriminate shrivelled walnuts and sound walnuts, which also makes a basis for on-line detection of in-shell shrivelled walnut. © 2019 Society of Chemical Industry.


Assuntos
Análise de Alimentos/métodos , Juglans/química , Nozes/química , Fenômenos Biomecânicos , Análise Discriminante , Análise de Alimentos/instrumentação , Controle de Qualidade
20.
Entropy (Basel) ; 21(5)2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-33267238

RESUMO

Information integration theory has been developed to quantify consciousness. Since conscious thought requires the integration of information, the degree of this integration can be used as a neural correlate (Φ) with the intent to measure degree of consciousness. Previous research has shown that the ability to integrate information can be improved by Darwinian evolution. The value Φ can change over many generations, and complex tasks require systems with at least a minimum Φ . This work was done using simple animats that were able to remember previous sensory inputs, but were incapable of fundamental change during their lifetime: actions were predetermined or instinctual. Here, we are interested in changes to Φ due to lifetime learning (also known as neuroplasticity). During lifetime learning, the system adapts to perform a task and necessitates a functional change, which in turn could change Φ . One can find arguments to expect one of three possible outcomes: Φ might remain constant, increase, or decrease due to learning. To resolve this, we need to observe systems that learn, but also improve their ability to learn over the many generations that Darwinian evolution requires. Quantifying Φ over the course of evolution, and over the course of their lifetimes, allows us to investigate how the ability to integrate information changes. To measure Φ , the internal states of the system must be experimentally observable. However, these states are notoriously difficult to observe in a natural system. Therefore, we use a computational model that not only evolves virtual agents (animats), but evolves animats to learn during their lifetime. We use this approach to show that a system that improves its performance due to feedback learning increases its ability to integrate information. In addition, we show that a system's ability to increase Φ correlates with its ability to increase in performance. This suggests that systems that are very plastic regarding Φ learn better than those that are not.

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