974,853 research outputs found

    Explicit and Implicit Processes in Human Aversive Conditioning

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    The ability to adapt to a changing environment is central to an organism’s success. The process of associating two stimuli (as in associative conditioning) requires very little in the way of neural machinery. In fact, organisms with only a few hundred neurons show conditioning that is specific to an associated cue. This type of learning is commonly referred to as implicit learning. The learning can be performed in the absence of the subject’s ability to describe it. One example of learning that is thought to be implicit is delay conditioning. Delay conditioning consists of a single cue (a tone, for example) that starts before, and then overlaps with, an outcome (like a pain stimulus). In addition to associating sensory cues, humans routinely link abstract concepts with an outcome. This more complex learning is often described as explicit since subjects are able to describe the link between the stimulus and outcome. An example of conditioning that requires this type of knowledge is trace conditioning. Trace conditioning includes a separation of a few seconds between the cue and outcome. Explicit learning is often proposed to involve a separate system, but the degree of separation between implicit associations and explicit learning is still debated. We describe aversive conditioning experiments in human subjects used to study the degree of interaction that takes place between explicit and implicit systems. We do this in three ways. First, if a higher order task (in this case a working memory task) is performed during conditioning, it reduces not only explicit learning but also implicit learning. Second, we describe the area of the brain involved in explicit learning during conditioning and confirm that it is active during both trace and delay conditioning. Third, using functional magnetic resonance imaging (fMRI), we describe hemodynamic activity changes in perceptual areas of the brain that occur during delay conditioning and persist after the learned association has faded. From these studies, we conclude that there is a strong interaction between explicit and implicit learning systems, with one often directly changing the function of the other.</p

    Crowdfunding : psychological conditioning

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    "Crowdfunding" jest stosunkowo nowym pojęciem; to neologizm, który powstał w 2006 roku. Słowo składa się z dwóch terminów: crowd ("tłum") oraz funding ("finansowanie"). Crowdfunding funkcjonuje za pośrednictwem specjalnych platform i Internetu, wykorzystuje płatności online. Celem niniejszego artykułu jest zdefiniowanie crowdfundingu, a także opisanie jego modeli i wskazanie na motywacje psychologiczne związane z dziedziną crowdfundingu. Ponadto przedstawione zostały niektóre z ostatnich badań na jego temat, które wskazują na psychologiczne i socjologiczne determinanty zachowań w sieci.Crowdfunding is a relatively new term; it’s a neologism that has been brought to live in 2006. The word itself is a blend of two terms: ‘crowd’ and ‘funding’ and the background for that term is connected with ‘crowdsourcing’. Crowdfunding use special platforms, web and online payments. The aim of the paper is mainly related to defining crowdfunding, describing models of crowdfunding and indicating some of psychological motivations and conditions to operate in crowdfunding realm. The analysis provides a clear picture of crowdfunding models and psy- chological motivations to crowdfunding. What is more, some of the recent researches and case studies will be presented to show some of the particular crowdfunding activities

    Associative memory stored by functional novel pathway rather than modifications of preexisting neuronal pathways

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    Associative conditioning involves changes in the processing pathways activated by sensory information to link the conditioned stimulus (CS) to the conditioned behavior. Thus, conditioning can recruit neuronal elements to form new pathways for the processing of the CS and/or can change the strength of existing pathways. Using a behavioral and systems level electrophysiological approach on a tractable invertebrate circuit generating feeding in the mollusk Lymnaea stagnalis, we identified three independent pathways for the processing of the CS amyl acetate used in appetitive conditioning. Two of these pathways, one suppressing and the other stimulating feeding, mediate responses to the CS in naive animals. The effects ofthese two pathways on feeding behavior are unaltered by conditioning. In contrast, the CS response ofa third stimulatory pathway is significantly enhanced after conditioning, becoming an importantcontributor to the overall CS response. This is unusual because, in most of the previous examples in which naive animals already respond to the CS, memory formation results from changes in the strength of pathways that mediate the existing response. Here, we show that, in the molluscan feeding system, both modified and unmodified pathways are activated in parallel by the CS after conditioning, and it is their integration that results in the conditioned respons

    Relating Question Type to Panel Conditioning: A Comparison between Trained and Fresh Respondents

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    Panel conditioning arises if respondents are influenced by participation in previous surveys, such that their answers differ significantly from the answers of individuals who are interviewed for the first time. Having two panels—a trained one and a completely fresh one—created a unique opportunity for analysing panel conditioning effects. To determine which type of question is sensitive to panel conditioning, 981 trained respondents and 2809 fresh respondents answered nine questions with different question types. The results in this paper show that panel conditioning only arise in knowledge questions. Questions on attitudes, actual behaviour, or facts were not sensitive to panel conditioning. Panel conditioning in knowledge questions was restricted to less-known subjects (more difficult questions), suggesting a relation between panel conditioning and cognition.panel conditioning;re-interviewing;measurement error;panel surveys

    Depolarization-activated potentiation of the T fiber synapse in the blue crab

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    The blue crab T fiber synapse, associated with the stretch receptor of the swimming leg, has a nonspiking presynaptic element that mediates tonic transmission. This synapse was isolated and a voltage clamp circuit was used to control the membrane potential at the release sites. The dependence of transmitter release on extracellular calcium, [Ca]o, was studied over a range of 2.5-40 mM. A power relationship of 2.7 was obtained between excitatory postsynaptic potential (EPSP) rate of rise and [Ca]o. Brief presynaptic depolarizing steps, 5-10 ms, presented at 0.5 Hz activated EPSP's of constant amplitude. Inserting a 300-ms pulse (conditioning pulse) between these test pulses potentiated the subsequent test EPSPs. This depolarization-activated potentiation (DAP) lasted for 10-20 s and decayed with a single exponential time course. The decay time course remained invariant with test pulse frequencies ranging from 0.11 to 1.1 Hz. The magnitude and decay time course of DAP were independent of the test pulse amplitudes. The magnitude of DAP was a function of conditioning pulse amplitudes. Large conditioning pulses activated large potentiations, whereas the decay time constants were not changed. The DAP is a Ca-dependent process. When the amplitude of conditioning pulses approached the Ca equilibrium potential, the magnitude of potentiation decreased. Repeated application of conditioning pulses, at 2-s intervals, did not produce additional potentiation beyond the level activated by the first conditioning pulse. Comparison of the conditioning EPSP waveforms activated repetitively indicated that potentiation lasted transiently, 100 ms, during a prolonged release. Possible mechanisms of the potentiation are discussed in light of these new findings.The blue crab T fiber synapse, associated with the stretch receptor of the swimming leg, has a nonspiking presynaptic element that mediates tonic transmission. This synapse was isolated and a voltage clamp circuit was used to control the membrane potential at the release sites. The dependence of transmitter release on extracellular calcium, [Ca]o, was studied over a range of 2.5-40 mM. A power relationship of 2.7 was obtained between excitatory postsynaptic potential (EPSP) rate of rise and [Ca]o. Brief presynaptic depolarizing steps, 5-10 ms, presented at 0.5 Hz activated EPSP's of constant amplitude. Inserting a 300-ms pulse (conditioning pulse) between these test pulses potentiated the subsequent test EPSPs. This depolarization-activated potentiation (DAP) lasted for 10-20 s and decayed with a single exponential time course. The decay time course remained invariant with test pulse frequencies ranging from 0.11 to 1.1 Hz. The magnitude and decay time course of DAP were independent of the test pulse amplitudes. The magnitude of DAP was a function of conditioning pulse amplitudes. Large conditioning pulses activated large potentiations, whereas the decay time constants were not changed. The DAP is a Ca-dependent process. When the amplitude of conditioning pulses approached the Ca equilibrium potential, the magnitude of potentiation decreased. Repeated application of conditioning pulses, at 2-s intervals, did not produce additional potentiation beyond the level activated by the first conditioning pulse. Comparison of the conditioning EPSP waveforms activated repetitively indicated that potentiation lasted transiently, 100 ms, during a prolonged release. Possible mechanisms of the potentiation are discussed in light of these new findings.NS-07942 - NINDS NIH HHS; NS-13742 - NINDS NIH HH

    Evaluative conditioning as a symbolic phenomenon: on the relation between evaluative conditioning, evaluative conditioning via instructions, and persuasion

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    Evaluative conditioning (EC) is sometimes portrayed as a primitive way of changing attitudes that is fundamentally different from persuasion via arguments. We provide a new perspective on the nature of EC and its relation to persuasion by exploring the idea that stimulus pairings can function as a symbol that conveys the nature of the relation between stimuli. We put forward the concept of symbolic EC to refer to changes in liking that occur because stimulus pairings function as symbols. The idea of symbolic EC is consistent with at least some current theories of persuasion. It clarifies what EC research can add to the understanding of the origins of our preferences and has implications for how (symbolic and non-symbolic) EC can be established, the boundaries of EC research, and cognitive and functional models of EC
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