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Sample records for aversive visual learning

  1. Appetitive and aversive visual learning in freely moving Drosophila

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    Christopher Schnaitmann

    2010-03-01

    Full Text Available To compare appetitive and aversive visual memories of the fruit fly Drosophila melanogaster, we developed a new paradigm for classical conditioning. Adult flies are trained en masse to differentially associate one of two visual conditioned stimuli (blue and green light as conditioned stimuli or CS with an appetitive or aversive chemical substance (unconditioned stimulus or US. In a test phase, flies are given a choice between the paired and the unpaired visual stimuli. Associative memory is measured based on altered visual preference in the test. If a group of flies has, for example, received a sugar reward with green light, they show a significantly higher preference for the green stimulus during the test than another group of flies having received the same reward with blue light. We demonstrate critical parameters for the formation of visual appetitive memory, such as training repetition, order of reinforcement, starvation, and individual conditioning. Furthermore, we show that formic acid can act as an aversive chemical reinforcer, yielding weak, yet significant, aversive memory. These results provide a basis for future investigations into the cellular and molecular mechanisms underlying visual memory and perception in Drosophila.

  2. Aversive reinforcement improves visual discrimination learning in free-flying honeybees.

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    Aurore Avarguès-Weber

    Full Text Available BACKGROUND: Learning and perception of visual stimuli by free-flying honeybees has been shown to vary dramatically depending on the way insects are trained. Fine color discrimination is achieved when both a target and a distractor are present during training (differential conditioning, whilst if the same target is learnt in isolation (absolute conditioning, discrimination is coarse and limited to perceptually dissimilar alternatives. Another way to potentially enhance discrimination is to increase the penalty associated with the distractor. Here we studied whether coupling the distractor with a highly concentrated quinine solution improves color discrimination of both similar and dissimilar colors by free-flying honeybees. As we assumed that quinine acts as an aversive stimulus, we analyzed whether aversion, if any, is based on an aversive sensory input at the gustatory level or on a post-ingestional malaise following quinine feeding. METHODOLOGY/PRINCIPAL FINDINGS: We show that the presence of a highly concentrated quinine solution (60 mM acts as an aversive reinforcer promoting rejection of the target associated with it, and improving discrimination of perceptually similar stimuli but not of dissimilar stimuli. Free-flying bees did not use remote cues to detect the presence of quinine solution; the aversive effect exerted by this substance was mediated via a gustatory input, i.e. via a distasteful sensory experience, rather than via a post-ingestional malaise. CONCLUSION: The present study supports the hypothesis that aversion conditioning is important for understanding how and what animals perceive and learn. By using this form of conditioning coupled with appetitive conditioning in the framework of a differential conditioning procedure, it is possible to uncover discrimination capabilities that may remain otherwise unsuspected. We show, therefore, that visual discrimination is not an absolute phenomenon but can be modulated by experience.

  3. Overcoming Learning Aversion in Evaluating and Managing Uncertain Risks.

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    Cox, Louis Anthony Tony

    2015-10-01

    Decision biases can distort cost-benefit evaluations of uncertain risks, leading to risk management policy decisions with predictably high retrospective regret. We argue that well-documented decision biases encourage learning aversion, or predictably suboptimal learning and premature decision making in the face of high uncertainty about the costs, risks, and benefits of proposed changes. Biases such as narrow framing, overconfidence, confirmation bias, optimism bias, ambiguity aversion, and hyperbolic discounting of the immediate costs and delayed benefits of learning, contribute to deficient individual and group learning, avoidance of information seeking, underestimation of the value of further information, and hence needlessly inaccurate risk-cost-benefit estimates and suboptimal risk management decisions. In practice, such biases can create predictable regret in selection of potential risk-reducing regulations. Low-regret learning strategies based on computational reinforcement learning models can potentially overcome some of these suboptimal decision processes by replacing aversion to uncertain probabilities with actions calculated to balance exploration (deliberate experimentation and uncertainty reduction) and exploitation (taking actions to maximize the sum of expected immediate reward, expected discounted future reward, and value of information). We discuss the proposed framework for understanding and overcoming learning aversion and for implementing low-regret learning strategies using regulation of air pollutants with uncertain health effects as an example.

  4. Reappraising social insect behavior through aversive responsiveness and learning.

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    Edith Roussel

    Full Text Available BACKGROUND: The success of social insects can be in part attributed to their division of labor, which has been explained by a response threshold model. This model posits that individuals differ in their response thresholds to task-associated stimuli, so that individuals with lower thresholds specialize in this task. This model is at odds with findings on honeybee behavior as nectar and pollen foragers exhibit different responsiveness to sucrose, with nectar foragers having higher response thresholds to sucrose concentration. Moreover, it has been suggested that sucrose responsiveness correlates with responsiveness to most if not all other stimuli. If this is the case, explaining task specialization and the origins of division of labor on the basis of differences in response thresholds is difficult. METHODOLOGY: To compare responsiveness to stimuli presenting clear-cut differences in hedonic value and behavioral contexts, we measured appetitive and aversive responsiveness in the same bees in the laboratory. We quantified proboscis extension responses to increasing sucrose concentrations and sting extension responses to electric shocks of increasing voltage. We analyzed the relationship between aversive responsiveness and aversive olfactory conditioning of the sting extension reflex, and determined how this relationship relates to division of labor. PRINCIPAL FINDINGS: Sucrose and shock responsiveness measured in the same bees did not correlate, thus suggesting that they correspond to independent behavioral syndromes, a foraging and a defensive one. Bees which were more responsive to shock learned and memorized better aversive associations. Finally, guards were less responsive than nectar foragers to electric shocks, exhibiting higher tolerance to low voltage shocks. Consequently, foragers, which are more sensitive, were the ones learning and memorizing better in aversive conditioning. CONCLUSIONS: Our results constitute the first integrative

  5. Conditioned and Latent Inhibition in Taste-Aversion Learning: Clarifying the Role of Learned Safety

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    Best, Michael R.

    1975-01-01

    The following experiments are an attempt to clarify the role of learned safety by investigating the applicability of the concept of conditioned inhibition to a taste-aversion procedure and by differentiating its effects fromthose of latent inhibition. (Author)

  6. Contrasting role of octopamine in appetitive and aversive learning in the crab Chasmagnathus.

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    Laura Kaczer

    Full Text Available BACKGROUND: Biogenic amines are implicated in reinforcing associative learning. Octopamine (OA is considered the invertebrate counterpart of noradrenaline and several studies in insects converge on the idea that OA mediates the reward in appetitive conditioning. However, it is possible to assume that OA could have a different role in an aversive conditioning. METHODOLOGY/PRINCIPAL FINDINGS: Here we pharmacologically studied the participation of OA in two learning processes in the crab Chasmagnathus granulatus, one appetitive and one aversive. It is shown that the aversive memory is impaired by an OA injection applied immediately or 30 minutes after the last training trial. By contrast, the appetitive memory is blocked by OA antagonists epinastine and mianserine, but enhanced by OA when injected together with the supply of a minimum amount of reinforcement. Finally, double-learning experiments in which crabs are given the aversive and the appetitive learning either successively or simultaneously allow us to study the interaction between both types of learning and analyze the presumed action of OA. We found that the appetitive training offered immediately, but not one hour, after an aversive training has an amnesic effect on the aversive memory, mimicking the effect and the kinetic of an OA injection. CONCLUSIONS/SIGNIFICANCE: Our results demonstrate that the role of OA is divergent in two memory processes of opposite signs: on the one hand it would mediate the reinforcement in appetitive learning, and on the other hand it has a deleterious effect over aversive memory consolidation.

  7. Muscarinic ACh Receptors Contribute to Aversive Olfactory Learning in Drosophila

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    Silva, Bryon; Molina-Fernández, Claudia; Ugalde, María Beatriz; Tognarelli, Eduardo I.; Angel, Cristian; Campusano, Jorge M.

    2015-01-01

    The most studied form of associative learning in Drosophila consists in pairing an odorant, the conditioned stimulus (CS), with an unconditioned stimulus (US). The timely arrival of the CS and US information to a specific Drosophila brain association region, the mushroom bodies (MB), can induce new olfactory memories. Thus, the MB is considered a coincidence detector. It has been shown that olfactory information is conveyed to the MB through cholinergic inputs that activate acetylcholine (ACh) receptors, while the US is encoded by biogenic amine (BA) systems. In recent years, we have advanced our understanding on the specific neural BA pathways and receptors involved in olfactory learning and memory. However, little information exists on the contribution of cholinergic receptors to this process. Here we evaluate for the first time the proposition that, as in mammals, muscarinic ACh receptors (mAChRs) contribute to memory formation in Drosophila. Our results show that pharmacological and genetic blockade of mAChRs in MB disrupts olfactory aversive memory in larvae. This effect is not explained by an alteration in the ability of animals to respond to odorants or to execute motor programs. These results show that mAChRs in MB contribute to generating olfactory memories in Drosophila. PMID:26380118

  8. Neurobiological mechanisms underlying the blocking effect in aversive learning.

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    Eippert, Falk; Gamer, Matthias; Büchel, Christian

    2012-09-19

    Current theories of classical conditioning assume that learning depends on the predictive relationship between events, not just on their temporal contiguity. Here we employ the classic experiment substantiating this reasoning-the blocking paradigm-in combination with functional magnetic resonance imaging (fMRI) to investigate whether human amygdala responses in aversive learning conform to these assumptions. In accordance with blocking, we demonstrate that significantly stronger behavioral and amygdala responses are evoked by conditioned stimuli that are predictive of the unconditioned stimulus than by conditioned stimuli that have received the same pairing with the unconditioned stimulus, yet have no predictive value. When studying the development of this effect, we not only observed that it was related to the strength of previous conditioned responses, but also that predictive compared with nonpredictive conditioned stimuli received more overt attention, as measured by fMRI-concurrent eye tracking, and that this went along with enhanced amygdala responses. We furthermore observed that prefrontal regions play a role in the development of the blocking effect: ventromedial prefrontal cortex (subgenual anterior cingulate) only exhibited responses when conditioned stimuli had to be established as nonpredictive for an outcome, whereas dorsolateral prefrontal cortex also showed responses when conditioned stimuli had to be established as predictive. Most importantly, dorsolateral prefrontal cortex connectivity to amygdala flexibly switched between positive and negative coupling, depending on the requirements posed by predictive relationships. Together, our findings highlight the role of predictive value in explaining amygdala responses and identify mechanisms that shape these responses in human fear conditioning.

  9. Muscarinic ACh Receptors Contribute to Aversive Olfactory Learning in Drosophila

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    Bryon Silva

    2015-01-01

    Full Text Available The most studied form of associative learning in Drosophila consists in pairing an odorant, the conditioned stimulus (CS, with an unconditioned stimulus (US. The timely arrival of the CS and US information to a specific Drosophila brain association region, the mushroom bodies (MB, can induce new olfactory memories. Thus, the MB is considered a coincidence detector. It has been shown that olfactory information is conveyed to the MB through cholinergic inputs that activate acetylcholine (ACh receptors, while the US is encoded by biogenic amine (BA systems. In recent years, we have advanced our understanding on the specific neural BA pathways and receptors involved in olfactory learning and memory. However, little information exists on the contribution of cholinergic receptors to this process. Here we evaluate for the first time the proposition that, as in mammals, muscarinic ACh receptors (mAChRs contribute to memory formation in Drosophila. Our results show that pharmacological and genetic blockade of mAChRs in MB disrupts olfactory aversive memory in larvae. This effect is not explained by an alteration in the ability of animals to respond to odorants or to execute motor programs. These results show that mAChRs in MB contribute to generating olfactory memories in Drosophila.

  10. Aversive learning in honeybees revealed by the olfactory conditioning of the sting extension reflex.

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    Vanina Vergoz

    Full Text Available Invertebrates have contributed greatly to our understanding of associative learning because they allow learning protocols to be combined with experimental access to the nervous system. The honeybee Apis mellifera constitutes a standard model for the study of appetitive learning and memory since it was shown, almost a century ago, that bees learn to associate different sensory cues with a reward of sugar solution. However, up to now, no study has explored aversive learning in bees in such a way that simultaneous access to its neural bases is granted. Using odorants paired with electric shocks, we conditioned the sting extension reflex, which is exhibited by harnessed bees when subjected to a noxious stimulation. We show that this response can be conditioned so that bees learn to extend their sting in response to the odorant previously punished. Bees also learn to extend the proboscis to one odorant paired with sugar solution and the sting to a different odorant paired with electric shock, thus showing that they can master both appetitive and aversive associations simultaneously. Responding to the appropriate odorant with the appropriate response is possible because two different biogenic amines, octopamine and dopamine subserve appetitive and aversive reinforcement, respectively. While octopamine has been previously shown to substitute for appetitive reinforcement, we demonstrate that blocking of dopaminergic, but not octopaminergic, receptors suppresses aversive learning. Therefore, aversive learning in honeybees can now be accessed both at the behavioral and neural levels, thus opening new research avenues for understanding basic mechanisms of learning and memory.

  11. Dorsal hippocampal lesions impair blocking but not latent inhibition of taste aversion learning in rats.

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    Gallo, M; Cándido, A

    1995-06-01

    The aim of the present experiments was to study the effect of nonselective electrolytic lesions of the rat dorsal hippocampus on 2 learning phenomena: the L.J. Kamin (1969) blocking effect and latent inhibition of taste aversion learning. Bilateral dorsal hippocampal lesions selectively impaired blocking induced by 1 saccharin-lithium chloride pairing previous to 1 serial compound (saccharin-cider vinegar)-lithium pairing, but lesions had no effect on latent inhibition of a saline aversion, induced by 6 saline preexposures, in the same group of animals. Moreover, dorsal hippocampal lesions did not affect latent inhibition of saccharin-conditioned aversion induced by 1 or 6 preexposures. It is argued that blocking and latent inhibition of taste aversion learning do not share a common neural mechanism.

  12. Activation of nucleus accumbens NMDA receptors differentially affects appetitive or aversive taste learning and memory

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    Luis eNuñez-Jaramillo

    2012-04-01

    Full Text Available Taste memory depends on motivational and post-ingestional consequences; thus, it can be aversive (e.g., conditioned taste aversion, CTA if a novel, palatable taste is paired with visceral malaise, or it can be appetitive if no intoxication appears after novel taste consumption, and a taste preference is developed. The nucleus accumbens (NAc plays a role in hedonic reactivity to taste stimuli, and recent findings suggest that reward and aversion are differentially encoded by the activity of NAc neurons. The present study examined whether the requirement for NMDA receptors in the NAc core during rewarding appetitive taste learning differs from that during aversive taste conditioning, as well as during retrieval of appetitive versus aversive taste memory, using the taste preference or CTA model, respectively. Bilateral infusions of NMDA (1 μg/μl, 0.5 μl into the NAc core were performed before acquisition or before retrieval of taste preference or CTA. Activation of NMDA receptors before taste preference training or CTA acquisition did not alter memory formation. Furthermore, NMDA injections before aversive taste retrieval had no effect on taste memory; however, 24 h later, CTA extinction was significantly delayed. Also, NMDA injections, made before familiar appetitive memory retrieval, interrupted the development of taste preference and produced a preference delay 24 h later. These results suggest that memory formation for a novel taste produces neurochemical changes in the NAc core that have differential requirements for NMDA receptors during retrieval of appetitive or aversive memory.

  13. ABA, AAB and ABC Renewal in Taste Aversion Learning

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    Bernal-Gamboa, Rodolfo; Juarez, Yectivani; Gonzalez-Martin, Gabriela; Carranza, Rodrigo; Sanchez-Carrasco, Livia; Nieto, Javier

    2012-01-01

    Context renewal is identified when the conditioned response (CR) elicited by an extinguished conditioned stimulus (CS) reappears as a result of changing the contextual cues during the test. Two experiments were designed for testing contextual renewal in a conditioned taste aversion preparation. Experiment 1 assessed ABA and AAB context renewal,…

  14. Taste aversion learning and aging: a comparison with the effect of dorsal hippocampal lesions in rats.

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    Moron, I; Ballesteros, M A; Candido, A; Gallo, M

    2002-01-01

    The relationship between hippocampal function and aging was explored in Wistar rats using taste aversion learning by comparing the performance of adult dorsal hippocampal lesioned and fifteen-month-old intact rats with that of adult intact rats. In experiment 1 the conditioned blocking phenomenon was absent in the hippocampal and the aging rats. Unlike the adult intact rats, the hippocampal and aging rats were not impaired in acquiring a learned aversion to a cider vinegar solution (3 %) presented as a serial compound with a previously conditioned saccharin solution (0.1 %). In experiment 2 both the hippocampal and the aging rats developed reduced aversions to a saline solution (0.5 %) followed by an i.p. injection of lithium chloride (0.15 M; 2 % b.w.) if the taste solution was previously preexposed without consequences. This latent inhibition effect was similar to that seen in intact adult rats. In both experiments, the aging rats exhibited enhanced conventional learned taste aversions. It is concluded that aging is not a unitary process but induces both hippocampal dependent and hippocampal independent complex changes in the functioning of the neural circuits, implementing taste aversion learning.

  15. Flavor aversion learning induced by lithium chloride in reptiles but not in amphibians.

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    Paradis, Sébastien; Cabanac, Michel

    2004-07-30

    Flavor aversion learning occurs when digestive illness follows ingestion of a novel food. Such learning has been shown to exist in mammals and birds. In this experiment, we looked for flavor aversion learning in amphibians (Bufo paracnemis, Pachytriton breviceps) and reptiles (Basiliscus vitattus, B. basiliscus, Eumeces schneideri, Mabuya multifasciata). After intake of the novel food, the animals received i.p. injection of either lithium chloride (LiCl), an effective illness inducer, or a saline solution. A week later, the LiCl injection had not affected the food intake of the amphibians whereas in the lizards it had produced a strong aversion to the flavor of the novel food. These results are consistent with the hypothesis that specific mental capacities emerged with reptiles.

  16. The combination of appetitive and aversive reinforcers and the nature of their interaction during auditory learning.

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    Ilango, A; Wetzel, W; Scheich, H; Ohl, F W

    2010-03-31

    Learned changes in behavior can be elicited by either appetitive or aversive reinforcers. It is, however, not clear whether the two types of motivation, (approaching appetitive stimuli and avoiding aversive stimuli) drive learning in the same or different ways, nor is their interaction understood in situations where the two types are combined in a single experiment. To investigate this question we have developed a novel learning paradigm for Mongolian gerbils, which not only allows rewards and punishments to be presented in isolation or in combination with each other, but also can use these opposite reinforcers to drive the same learned behavior. Specifically, we studied learning of tone-conditioned hurdle crossing in a shuttle box driven by either an appetitive reinforcer (brain stimulation reward) or an aversive reinforcer (electrical footshock), or by a combination of both. Combination of the two reinforcers potentiated speed of acquisition, led to maximum possible performance, and delayed extinction as compared to either reinforcer alone. Additional experiments, using partial reinforcement protocols and experiments in which one of the reinforcers was omitted after the animals had been previously trained with the combination of both reinforcers, indicated that appetitive and aversive reinforcers operated together but acted in different ways: in this particular experimental context, punishment appeared to be more effective for initial acquisition and reward more effective to maintain a high level of conditioned responses (CRs). The results imply that learning mechanisms in problem solving were maximally effective when the initial punishment of mistakes was combined with the subsequent rewarding of correct performance.

  17. Coordinated activity of ventral tegmental neurons adapts to appetitive and aversive learning.

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    Yunbok Kim

    Full Text Available Our understanding of how value-related information is encoded in the ventral tegmental area (VTA is based mainly on the responses of individual putative dopamine neurons. In contrast to cortical areas, the nature of coordinated interactions between groups of VTA neurons during motivated behavior is largely unknown. These interactions can strongly affect information processing, highlighting the importance of investigating network level activity. We recorded the activity of multiple single units and local field potentials (LFP in the VTA during a task in which rats learned to associate novel stimuli with different outcomes. We found that coordinated activity of VTA units with either putative dopamine or GABA waveforms was influenced differently by rewarding versus aversive outcomes. Specifically, after learning, stimuli paired with a rewarding outcome increased the correlation in activity levels between unit pairs whereas stimuli paired with an aversive outcome decreased the correlation. Paired single unit responses also became more redundant after learning. These response patterns flexibly tracked the reversal of contingencies, suggesting that learning is associated with changing correlations and enhanced functional connectivity between VTA neurons. Analysis of LFP recorded simultaneously with unit activity showed an increase in the power of theta oscillations when stimuli predicted reward but not an aversive outcome. With learning, a higher proportion of putative GABA units were phase locked to the theta oscillations than putative dopamine units. These patterns also adapted when task contingencies were changed. Taken together, these data demonstrate that VTA neurons organize flexibly as functional networks to support appetitive and aversive learning.

  18. Effects of anticipatory anxiety and visual input on postural sway in an aversive situation.

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    Ishida, Mitsuo; Saitoh, Junko; Wada, Maki; Nagai, Masanori

    2010-04-19

    We have previously reported that state anxiety scores were positively correlated with postural sway while standing upright and gazing at a visual target (Ohno et al., 2004 [16]). The present study examines the effect of anticipatory anxiety and visual input on postural control in healthy individuals. An unpredictable aversive sound (100dB SPL) was delivered in order to induce anticipatory anxiety. Participants were asked to stand upright on a force plate with their eyes open and closed, and their center of pressure (COP) was measured. Analysis of the postural parameters revealed that the path lengths of the COP and the enveloped areas were greater in the anticipatory situation with the aversive sound than in the silent situation. Fast Fourier transform analysis showed that the frequency component related to vestibular inputs (0.1-1.0Hz) was increased during the anticipatory situation. The lower frequency (anticipatory anxiety in healthy participants amplified the sway regardless of whether the eyes were open or closed, and that the vestibular inputs greatly influenced the amplification of postural sway.

  19. Negative learning bias is associated with risk aversion in a genetic animal model of depression

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    Steven John Shabel

    2014-01-01

    Full Text Available The lateral habenula (LHb is activated by aversive stimuli and the omission of reward, inhibited by rewarding stimuli and is hyperactive in helpless rats – an animal model of depression. Here we test the hypothesis that congenital learned helpless (cLH rats are more sensitive to decreases in reward size and/or less sensitive to increases in reward than wild-type (WT control rats. Consistent with the hypothesis, we found that cLH rats were slower to switch preference between two responses after a small upshift in reward size on one of the responses but faster to switch their preference after a small downshift in reward size. cLH rats were also more risk-averse than WT rats – they chose a response delivering a constant amount of reward (safe response more often than a response delivering a variable amount of reward (risky response compared to WT rats. Interestingly, the level of bias towards negative events was associated with the rat’s level of risk aversion when compared across individual rats. cLH rats also showed impaired appetitive Pavlovian conditioning but more accurate responding in a two-choice sensory discrimination task. These results are consistent with a negative learning bias and risk aversion in cLH rats, suggesting abnormal processing of rewarding and aversive events in the LHb of cLH rats.

  20. Roles of octopaminergic and dopaminergic neurons in mediating reward and punishment signals in insect visual learning.

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    Unoki, Sae; Matsumoto, Yukihisa; Mizunami, Makoto

    2006-10-01

    Insects, like vertebrates, have considerable ability to associate visual, olfactory or other sensory signals with reward or punishment. Previous studies in crickets, honey bees and fruit-flies have suggested that octopamine (OA, invertebrate counterpart of noradrenaline) and dopamine (DA) mediate various kinds of reward and punishment signals in olfactory learning. However, whether the roles of OA and DA in mediating positive and negative reinforcing signals can be generalized to learning of sensory signals other than odors remained unknown. Here we first established a visual learning paradigm in which to associate a visual pattern with water reward or saline punishment for crickets and found that memory after aversive conditioning decayed much faster than that after appetitive conditioning. Then, we pharmacologically studied the roles of OA and DA in appetitive and aversive forms of visual learning. Crickets injected with epinastine or mianserin, OA receptor antagonists, into the hemolymph exhibited a complete impairment of appetitive learning to associate a visual pattern with water reward, but aversive learning with saline punishment was unaffected. By contrast, fluphenazine, chlorpromazine or spiperone, DA receptor antagonists, completely impaired aversive learning without affecting appetitive learning. The results demonstrate that OA and DA participate in reward and punishment conditioning in visual learning. This finding, together with results of previous studies on the roles of OA and DA in olfactory learning, suggests ubiquitous roles of the octopaminergic reward system and dopaminergic punishment system in insect learning.

  1. Travel Choice Inertia: The Joint Role of Risk Aversion and Learning

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    C.G. Chorus (Casper); B.G.C. Dellaert (Benedict)

    2010-01-01

    textabstractThis paper shows how travellers that are faced with a series of risky choices become behaviourally inert due to a combination of risk aversion and learning. Our theoretical analyses complement other studies that conceive inertia as resulting from the wish to save cognitive resources. We

  2. Aversive learning and generalization predict subclinical levels of anxiety : a six-month longitudinal study

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    Lenaert, Bert; Boddez, Yannick; Griffith, James W; Vervliet, Bram; Schruers, Koen; Hermans, Dirk

    2014-01-01

    The identification of premorbid markers of risk for psychopathology is one of the most important challenges for present-day psychiatric research. This study focuses on behavioral vulnerability factors that contribute to the development of anxiety. Little is known about the role of aversive learning

  3. Is avoiding an aversive outcome rewarding? Neural substrates of avoidance learning in the human brain.

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    Kim, Hackjin; Shimojo, Shinsuke; O'Doherty, John P

    2006-07-01

    Avoidance learning poses a challenge for reinforcement-based theories of instrumental conditioning, because once an aversive outcome is successfully avoided an individual may no longer experience extrinsic reinforcement for their behavior. One possible account for this is to propose that avoiding an aversive outcome is in itself a reward, and thus avoidance behavior is positively reinforced on each trial when the aversive outcome is successfully avoided. In the present study we aimed to test this possibility by determining whether avoidance of an aversive outcome recruits the same neural circuitry as that elicited by a reward itself. We scanned 16 human participants with functional MRI while they performed an instrumental choice task, in which on each trial they chose from one of two actions in order to either win money or else avoid losing money. Neural activity in a region previously implicated in encoding stimulus reward value, the medial orbitofrontal cortex, was found to increase, not only following receipt of reward, but also following successful avoidance of an aversive outcome. This neural signal may itself act as an intrinsic reward, thereby serving to reinforce actions during instrumental avoidance.

  4. Auditory-visual aversive stimuli modulate the conscious experience of fear.

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    Taffou, Marine; Guerchouche, Rachid; Drettakis, George; Viaud-Delmon, Isabelle

    2013-01-01

    In a natural environment, affective information is perceived via multiple senses, mostly audition and vision. However, the impact of multisensory information on affect remains relatively undiscovered. In this study, we investigated whether the auditory-visual presentation of aversive stimuli influences the experience of fear. We used the advantages of virtual reality to manipulate multisensory presentation and to display potentially fearful dog stimuli embedded in a natural context. We manipulated the affective reactions evoked by the dog stimuli by recruiting two groups of participants: dog-fearful and non-fearful participants. The sensitivity to dog fear was assessed psychometrically by a questionnaire and also at behavioral and subjective levels using a Behavioral Avoidance Test (BAT). Participants navigated in virtual environments, in which they encountered virtual dog stimuli presented through the auditory channel, the visual channel or both. They were asked to report their fear using Subjective Units of Distress. We compared the fear for unimodal (visual or auditory) and bimodal (auditory-visual) dog stimuli. Dog-fearful participants as well as non-fearful participants reported more fear in response to bimodal audiovisual compared to unimodal presentation of dog stimuli. These results suggest that fear is more intense when the affective information is processed via multiple sensory pathways, which might be due to a cross-modal potentiation. Our findings have implications for the field of virtual reality-based therapy of phobias. Therapies could be refined and improved by implicating and manipulating the multisensory presentation of the feared situations.

  5. Histone acetylation in the olfactory bulb of young rats facilitates aversive olfactory learning and synaptic plasticity.

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    Wang, Y-J; Okutani, F; Murata, Y; Taniguchi, M; Namba, T; Kaba, H

    2013-03-01

    Epigenetic mechanisms play an important role in memory formation and synaptic plasticity. Specifically, histone-associated heterochromatin undergoes changes in structure during the early stages of long-term memory formation. In keeping with the classical conditioning paradigm, young rats have been shown to exhibit aversion to an odor stimulus initially presented during foot shock. We previously showed that synaptic plasticity at the dendrodendritic synapses between mitral and granule cells in the olfactory bulb (OB) underlies this aversive olfactory learning. However, the epigenetic mechanisms involved are not well characterized. Therefore, we examined whether intrabulbar infusion of trichostatin A (TSA), a histone deacetylase inhibitor, facilitates olfactory learning in young rats. TSA infusion during odor-shock training enhanced a conditioned odor aversion in a dose-dependent manner and prolonged the learned aversion. Western blot and immunohistochemical analyses showed that the level of histone H4 acetylation significantly increased until 4 h after odor-shock training in both mitral and granule cells in the OB, whereas histone H3 acetylation returned to the control level at 2 h after the training. We also obtained evidence that TSA infusion elevated acetylation of histone H4 or H3. Furthermore, in vitro electrophysiological analysis using slices of the OB revealed that application of TSA significantly enhanced the long-term potentiation induced in synaptic transmission from mitral to granule cells at dendrodendritic synapses. Taken together, these results provide evidence that histone H4 and H3 acetylation in the OB is an epigenetic mechanism associated with aversive olfactory learning in young rats.

  6. Induction of aversive learning through thermogenetic activation of Kenyon cell ensembles in Drosophila.

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    Vasmer, David; Pooryasin, Atefeh; Riemensperger, Thomas; Fiala, André

    2014-01-01

    Drosophila represents a model organism to analyze neuronal mechanisms underlying learning and memory. Kenyon cells of the Drosophila mushroom body are required for associative odor learning and memory retrieval. But is the mushroom body sufficient to acquire and retrieve an associative memory? To answer this question we have conceived an experimental approach to bypass olfactory sensory input and to thermogenetically activate sparse and random ensembles of Kenyon cells directly. We found that if the artifical activation of Kenyon cell ensembles coincides with a salient, aversive stimulus learning was induced. The animals adjusted their behavior in a subsequent test situation and actively avoided reactivation of these Kenyon cells. Our results show that Kenyon cell activity in coincidence with a salient aversive stimulus can suffice to form an associative memory. Memory retrieval is characterized by a closed feedback loop between a behavioral action and the reactivation of sparse ensembles of Kenyon cells.

  7. Induction of aversive learning through thermogenetic activation of Kenyon cell ensembles in Drosophila

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    David eVasmer

    2014-05-01

    Full Text Available Drosophila represents a model organism to analyze neuronal mechanisms underlying learning and memory. Kenyon cells of the Drosophila mushroom body are required for associative odor learning and memory retrieval. But is the mushroom body sufficient to acquire and retrieve an associative memory? To answer this question we have conceived an experimental approach to bypass olfactory sensory input and to thermogenetically activate sparse and random ensembles of Kenyon cells directly. We found that if the artifical activation of Kenyon cell ensembles coincides with a salient, aversive stimulus learning was induced The animals adjusted their behavior in a subsequent test situation and actively avoided reactivation of these Kenyon cells. Our results show that Kenyon cell activity in coincidence with a salient aversive stimulus can suffice to form an associative memory. Memory retrieval is characterized by a closed feedback loop between a behavioral action and the reactivation of sparse ensembles of Kenyon cells.

  8. Visual Impediments to Learning

    Directory of Open Access Journals (Sweden)

    Noëlla Piquette, PhD

    2013-07-01

    Full Text Available Cognition, learning, and motor planning are dependent upon accurate encoding of stimuli from the environment. If there is an error in, or an impediment to, sensory perception, higher cognitive functions, such as reading, memory, emotional awareness, and impulse control can be affected. In schools, deficiencies of the visual process impede and impair reading acquisition and learning and influence other behavior. Children are affected by different types of functional impediments to eyesight and visual function. The degree to which children are impacted varies according to the depth and nature of the impediments present, and to some degree to socioeconomic status. Some children are at a greater disadvantage simply because of the greater visual demands of the neo-traditional classroom. These visual impediments to learning (VIL are rarely detected in common sight screenings and are associated with limited socioeconomic success and increased criminality. Significant VIL limit academic and life outcomes, with some ethnicities affected by a greater prevalence of reading-impairing impediments. This presents difficulties for various public agencies at all levels of government. To complicate matters further, children who are affected by vision difficulties will most often not report the problem, nor will VIL be detected during standard pediatric or psychoeducational assessment.VIL are described in brief, as is how they alter children’s academic outcomes, health, and behavior. A model of sufficient vision care in the prevention and management of most vision-related learning and behavioral difficulties is proposed. The position is advanced that ensuring a

  9. Virulent bacterial infection improves aversive learning performance in Drosophila melanogaster.

    Science.gov (United States)

    Babin, Aurélie; Kolly, Sylvain; Kawecki, Tadeusz J

    2014-10-01

    Virulent infections are expected to impair learning ability, either as a direct consequence of stressed physiological state or as an adaptive response that minimizes diversion of energy from immune defense. This prediction has been well supported for mammals and bees. Here, we report an opposite result in Drosophila melanogaster. Using an odor-mechanical shock conditioning paradigm, we found that intestinal infection with bacterial pathogens Pseudomonas entomophila or Erwinia c. carotovora improved flies' learning performance after a 1h retention interval. Infection with P. entomophila (but not E. c. carotovora) also improved learning performance after 5 min retention. No effect on learning performance was detected for intestinal infections with an avirulent GacA mutant of P. entomophila or for virulent systemic (hemocoel) infection with E. c. carotovora. Assays of unconditioned responses to odorants and shock do not support a major role for changes in general responsiveness to stimuli in explaining the changes in learning performance, although differences in their specific salience for learning cannot be excluded. Our results demonstrate that the effects of pathogens on learning performance in insects are less predictable than suggested by previous studies, and support the notion that immune stress can sometimes boost cognitive abilities.

  10. Bilateral tetrodotoxin blockade of the rat vestibular nuclei substitutes the natural unconditioned stimulus in taste aversion learning.

    Science.gov (United States)

    Ballesteros, M A; Gallo, M

    2000-02-04

    The aversive effects of bilateral transient blockade of the lateral vestibular nucleus caused by tetrodotoxin microinjections were tested using conditioned taste aversion in the first experiment. Male Wistar rats received tetrodotoxin injections (10 ng) after drinking a coffee solution (0.5%), either in the lateral vestibular nucleus (LVN), the parabrachial nucleus or the dopaminergic area A8. Two days later they drank a cider vinegar solution (3%) not followed by injections. In a later choice test, only the group receiving the injection in the lateral vestibular nucleus displayed a coffee aversion. In a second experiment the role of the peripheral vestibular symptoms induced by LVN inactivation on substituting the aversive stimulus was explored in the same behavioral task. Rats anesthetized (Pentobarbital, 25 mg/kg) before tetrodoxin LVN blockade, that did not show peripheral symptoms, did not develop learned aversions. The coffee preference ratios did not differ to those animals receiving only anesthesia or those that remained undisturbed. These results showed that the bilateral blockade of the vestibular nuclei may induce peripheral vestibular symptoms that that may substitute the aversive stimulus in taste aversion learning.

  11. Visual learning in multisensory environments.

    Science.gov (United States)

    Jacobs, Robert A; Shams, Ladan

    2010-04-01

    We study the claim that multisensory environments are useful for visual learning because nonvisual percepts can be processed to produce error signals that people can use to adapt their visual systems. This hypothesis is motivated by a Bayesian network framework. The framework is useful because it ties together three observations that have appeared in the literature: (a) signals from nonvisual modalities can "teach" the visual system; (b) signals from nonvisual modalities can facilitate learning in the visual system; and (c) visual signals can become associated with (or be predicted by) signals from nonvisual modalities. Experimental data consistent with each of these observations are reviewed.

  12. Gene Network Analysis in Amygdala following Taste Aversion Learning in Rats

    Directory of Open Access Journals (Sweden)

    Siva K. Panguluri

    2013-01-01

    Full Text Available Conditioned taste aversion (CTA is an adaptive behavior that benefits survival of animals including humans and also serves as a powerful model to study the neural mechanisms of learning. Memory formation is a necessary component of CTA learning and involves neural processing and regulation of gene expression in the amygdala. Many studies have been focused on the identification of intracellular signaling cascades involved in CTA, but not late responsive genes underlying the long-lasting behavioral plasticity. In this study, we explored in silico experiments to identify persistent changes in gene expression associated with CTA in rats. We used oligonucleotide microarrays to identify 248 genes in the amygdala regulated by CTA. Pathway Studio and IPA software analyses showed that the differentially expressed genes in the amygdala fall in diverse functional categories such as behavior, psychological disorders, nervous system development and function, and cell-to-cell signaling. Conditioned taste aversion is a complex behavioral trait which involves association of visceral and taste inputs, consolidation of taste and visceral information, memory formation, retrieval of stored information, and extinction phase. In silico analysis of differentially expressed genes is therefore necessary to manipulate specific phase/stage of CTA to understand the molecular insight.

  13. Patients with schizophrenia show increased aversion to angry faces in an associative learning task

    Science.gov (United States)

    Evans, Simon; Shergill, Sukhwinder S.; Chouhan, Viraj; Collier, Tracy; Averbeck, Bruno B.

    2012-01-01

    Background We were interested in examining the relationship between socially-relevant stimuli and decision processes in patients with schizophrenia. Methods We tested patients with schizophrenia and healthy controls on a stochastically-rewarded associative learning task. Participants had to determine through trial and error which of two faces was associated with a higher chance of reward. One face was angry, the other happy. Results Both patients and healthy controls were able to do the task at above-chance accuracy, and there was no significant difference in overall accuracy between groups. Both groups also reliably preferred the happy face, such that they selected it more often than the angry face on the basis of the same amount of positive vs. negative feedback. Interestingly, however, patients were significantly more averse to the angry face, such that they chose it less often than control participants when the reward feedback strongly supported the angry face as the best choice. Conclusions Patients show an increased aversion to angry faces, in a task in which they must learn to associate rewards with expressions. PMID:20961475

  14. Reflexive Learning through Visual Methods

    DEFF Research Database (Denmark)

    Frølunde, Lisbeth

    2014-01-01

    What. This chapter concerns how visual methods and visual materials can support visually oriented, collaborative, and creative learning processes in education. The focus is on facilitation (guiding, teaching) with visual methods in learning processes that are designerly or involve design. Visual...... methods are exemplified through two university classroom cases about collaborative idea generation processes. The visual methods and materials in the cases are photo elicitation using photo cards, and modeling with LEGO Serious Play sets. Why. The goal is to encourage the reader, whether student...... or professional, to facilitate with visual methods in a critical, reflective, and experimental way. The chapter offers recommendations for facilitating with visual methods to support playful, emergent designerly processes. The chapter also has a critical, situated perspective. Where. This chapter offers case...

  15. Aversiveness of sounds in phocid seals: psycho-physiological factors, learning processes and motivation.

    Science.gov (United States)

    Götz, Thomas; Janik, Vincent M

    2010-05-01

    Aversiveness of sounds and its underlying physiological mechanisms in mammals are poorly understood. In this study we tested the influence of psychophysical parameters, motivation and learning processes on the aversiveness of anthropogenic underwater noise in phocid seals (Halichoerus grypus and Phoca vitulina). We compared behavioural responses of seals to playbacks of sounds based on a model of sensory unpleasantness for humans, sounds from acoustic deterrent devices and sounds with assumed neutral properties in different contexts of food motivation. In a captive experiment with food presentation, seals habituated quickly to all sound types presented at normalised received levels of 146 dB re. 1 microPa (r.m.s., root mean square). However, the fast habituation of avoidance behaviour was also accompanied by a weak sensitisation process affecting dive times and place preference in the pool. Experiments in the wild testing animals without food presentation revealed differential responses of seals to different sound types. We observed avoidance behaviour at received levels of 135-144 dB re. 1 microPa (sensation levels of 59-79 dB). In this experiment, sounds maximised for 'roughness' perceived as unpleasant by humans also caused the strongest avoidance responses in seals, suggesting that sensory pleasantness may be the result of auditory processing that is not restricted to humans. Our results highlight the importance of considering the effects of acoustic parameters other than the received level as well as animal motivation and previous experience when assessing the impacts of anthropogenic noise on animals.

  16. Learning from Balance Sheet Visualization

    Science.gov (United States)

    Tanlamai, Uthai; Soongswang, Oranuj

    2011-01-01

    This exploratory study examines alternative visuals and their effect on the level of learning of balance sheet users. Executive and regular classes of graduate students majoring in information technology in business were asked to evaluate the extent of acceptance and enhanced capability of these alternative visuals toward their learning…

  17. Anxious individuals have difficulty learning the causal statistics of aversive environments.

    Science.gov (United States)

    Browning, Michael; Behrens, Timothy E; Jocham, Gerhard; O'Reilly, Jill X; Bishop, Sonia J

    2015-04-01

    Statistical regularities in the causal structure of the environment enable us to predict the probable outcomes of our actions. Environments differ in the extent to which action-outcome contingencies are stable or volatile. Difficulty in being able to use this information to optimally update outcome predictions might contribute to the decision-making difficulties seen in anxiety. We tested this using an aversive learning task manipulating environmental volatility. Human participants low in trait anxiety matched updating of their outcome predictions to the volatility of the current environment, as predicted by a Bayesian model. Individuals with high trait anxiety showed less ability to adjust updating of outcome expectancies between stable and volatile environments. This was linked to reduced sensitivity of the pupil dilatory response to volatility, potentially indicative of altered norepinephrinergic responsivity to changes in this aspect of environmental information.

  18. Oxytocin Decreases Aversion to Angry Faces in an Associative Learning Task

    Science.gov (United States)

    Evans, Simon; Shergill, Sukhwinder S; Averbeck, Bruno B

    2010-01-01

    Social and financial considerations are often integrated when real life decisions are made, and recent studies have provided evidence that similar brain networks are engaged when either social or financial information is integrated. Other studies, however, have suggested that the neuropeptide oxytocin can specifically affect social behaviors, which would suggest separable mechanisms at the pharmacological level. Thus, we examined the hypothesis that oxytocin would specifically affect social and not financial information in a decision making task, in which participants learned which of the two faces, one smiling and the other angry or sad, was most often being rewarded. We found that oxytocin specifically decreased aversion to angry faces, without affecting integration of positive or negative financial feedback or choices related to happy vs sad faces. PMID:20844475

  19. Social signals and aversive learning in honey bee drones and workers

    Directory of Open Access Journals (Sweden)

    Arian Avalos

    2017-01-01

    Full Text Available The dissemination of information is a basic element of group cohesion. In honey bees (Apis mellifera Linnaeus 1758, like in other social insects, the principal method for colony-wide information exchange is communication via pheromones. This medium of communication allows multiple individuals to conduct tasks critical to colony survival. Social signaling also establishes conflict at the level of the individual who must trade-off between attending to the immediate environment or the social demand. In this study we examined this conflict by challenging highly social worker honey bees, and less social male drone honey bees undergoing aversive training by presenting them with a social stress signal (isopentyl acetate, IPA. We utilized IPA exposure methods that caused lower learning performance in appetitive learning in workers. Exposure to isopentyl acetate (IPA did not affect performance of drones and had a dose-specific effect on worker response, with positive effects diminishing at higher IPA doses. The IPA effects are specific because non-social cues, such as the odor cineole, improve learning performance in drones, and social homing signals (geraniol did not have a discernible effect on drone or worker performance. We conclude that social signals do generate conflict and that response to them is dependent on signal relevance to the individual as well as the context. We discuss the effect of social signal on learning both related to its social role and potential evolutionary history.

  20. Social signals and aversive learning in honey bee drones and workers

    Science.gov (United States)

    Pérez, Eddie; Vallejo, Lianna; Pérez, María E.; Abramson, Charles I.; Giray, Tugrul

    2017-01-01

    ABSTRACT The dissemination of information is a basic element of group cohesion. In honey bees (Apis mellifera Linnaeus 1758), like in other social insects, the principal method for colony-wide information exchange is communication via pheromones. This medium of communication allows multiple individuals to conduct tasks critical to colony survival. Social signaling also establishes conflict at the level of the individual who must trade-off between attending to the immediate environment or the social demand. In this study we examined this conflict by challenging highly social worker honey bees, and less social male drone honey bees undergoing aversive training by presenting them with a social stress signal (isopentyl acetate, IPA). We utilized IPA exposure methods that caused lower learning performance in appetitive learning in workers. Exposure to isopentyl acetate (IPA) did not affect performance of drones and had a dose-specific effect on worker response, with positive effects diminishing at higher IPA doses. The IPA effects are specific because non-social cues, such as the odor cineole, improve learning performance in drones, and social homing signals (geraniol) did not have a discernible effect on drone or worker performance. We conclude that social signals do generate conflict and that response to them is dependent on signal relevance to the individual as well as the context. We discuss the effect of social signal on learning both related to its social role and potential evolutionary history. PMID:27895050

  1. Social signals and aversive learning in honey bee drones and workers.

    Science.gov (United States)

    Avalos, Arian; Pérez, Eddie; Vallejo, Lianna; Pérez, María E; Abramson, Charles I; Giray, Tugrul

    2017-01-15

    The dissemination of information is a basic element of group cohesion. In honey bees (Apis mellifera Linnaeus 1758), like in other social insects, the principal method for colony-wide information exchange is communication via pheromones. This medium of communication allows multiple individuals to conduct tasks critical to colony survival. Social signaling also establishes conflict at the level of the individual who must trade-off between attending to the immediate environment or the social demand. In this study we examined this conflict by challenging highly social worker honey bees, and less social male drone honey bees undergoing aversive training by presenting them with a social stress signal (isopentyl acetate, IPA). We utilized IPA exposure methods that caused lower learning performance in appetitive learning in workers. Exposure to isopentyl acetate (IPA) did not affect performance of drones and had a dose-specific effect on worker response, with positive effects diminishing at higher IPA doses. The IPA effects are specific because non-social cues, such as the odor cineole, improve learning performance in drones, and social homing signals (geraniol) did not have a discernible effect on drone or worker performance. We conclude that social signals do generate conflict and that response to them is dependent on signal relevance to the individual as well as the context. We discuss the effect of social signal on learning both related to its social role and potential evolutionary history.

  2. Rules and mechanisms of punishment learning in honey bees: the aversive conditioning of the sting extension response.

    Science.gov (United States)

    Tedjakumala, Stevanus Rio; Giurfa, Martin

    2013-08-15

    Honeybees constitute established model organisms for the study of appetitive learning and memory. In recent years, the establishment of the technique of olfactory conditioning of the sting extension response (SER) has yielded new insights into the rules and mechanisms of aversive learning in insects. In olfactory SER conditioning, a harnessed bee learns to associate an olfactory stimulus as the conditioned stimulus with the noxious stimulation of an electric shock as the unconditioned stimulus. Here, we review the multiple aspects of honeybee aversive learning that have been uncovered using Pavlovian conditioning of the SER. From its behavioral principles and sensory variants to its cellular bases and implications for understanding social organization, we present the latest advancements in the study of punishment learning in bees and discuss its perspectives in order to define future research avenues and necessary improvements. The studies presented here underline the importance of studying honeybee learning not only from an appetitive but also from an aversive perspective, in order to uncover behavioral and cellular mechanisms of individual and social plasticity.

  3. Caenorhabditis elegans employs innate and learned aversion in response to bacterial toxic metabolites tambjamine and violacein

    Science.gov (United States)

    Ballestriero, Francesco; Nappi, Jadranka; Zampi, Giuseppina; Bazzicalupo, Paolo; Di Schiavi, Elia; Egan, Suhelen

    2016-01-01

    Bacteriovorus eukaryotes such as nematodes are one of the major natural predators of bacteria. In their defense bacteria have evolved a number of strategies to avoid predation, including the production of deterrent or toxic metabolites, however little is known regarding the response of predators towards such bacterial defenses. Here we use the nematode C. elegans as a model to study a predators’ behavioral response towards two toxic bacterial metabolites, tambjamine YP1 and violacein. We found that C. elegans displays an innate avoidance behavior towards tambjamine YP1, however requires previous exposure to violacein before learning to avoid this metabolite. The learned avoidance of violacein is specific, reversible, is mediated via the nematode olfactory apparatus (aversive olfactory learning) and is reduced in the absence of the neurotransmitter serotonin. These multiple strategies to evade bacterial toxic metabolites represent a valuable behavioral adaptation allowing bacteriovorus predators to distinguish between good and bad food sources, thus contributing to the understanding of microbial predator-prey interactions. PMID:27384057

  4. Reactivation of an aversive memory modulates learning strategy preference in male rats.

    Science.gov (United States)

    Hawley, Wayne R; Grissom, Elin M; Patel, Jessica M; Hodges, Kelly S; Dohanich, Gary P

    2013-01-01

    Reminders of an aversive event adversely impact retrieval of hippocampus-dependent memories and exacerbate stress-induced levels of anxiety. Interestingly, stress and anxiety shift control over learning away from the hippocampus and toward the striatum. The aims of the current study were to determine whether spatial memory and learning strategy are impacted by reminders of a stressor. Adult male Long-Evans rats (N = 47) were subjected to an inhibitory avoidance (IA) training trial in which 32 rats were exposed (3 s) to a single inescapable electrical footshock (0.6 mA). Prior to the retention trial of a Y-maze task and the probe trials of two different learning strategy tasks, some of the rats that were exposed to the footshock (n = 17) were reminded of the stressor on an IA retrieval trial. Both groups of rats exposed to the initial stressor exhibited hypoactivity, but no impairment in spatial memory, on the Y-maze task conducted 1 week after exposure to the footshock. One month after exposure to footshock, both groups of rats exposed to the initial stressor tended to prefer a striatum-dependent learning strategy on a water T-maze task. However, 2 months after exposure to footshock, only shocked rats that were reminded of the stressor exhibited a preference for a striatum-dependent learning strategy on a visible-platform water maze task, which corresponded with lower levels of activity in an open field. The results indicate that reminders of a stressor perpetuate the deleterious effects of stress on affective and cognitive processes.

  5. Differential effects of wake promoting drug Modafinil in aversive learning paradigms

    Directory of Open Access Journals (Sweden)

    Bharanidharan eShanmugasundaram

    2015-08-01

    Full Text Available Modafinil (MO an inhibitor of the dopamine transporter was initially approved to treat narcolepsy, a sleep related disorder in humans. One interesting side-effect of this drug, which emerged from preclinical and clinical studies, is the facilitation of cognitive performance. So far, this was primarily shown in appetitive learning paradigms, but it is yet unclear whether MO exerts a more general cognitive enhancement effect. Thus, the aim of the present study in rats was to extend these findings by testing the effects of MO in two aversive paradigms, Pavlovian fear conditioning (FC and the operant two-way active avoidance (TWA learning paradigms. We discovered a differential, task-dependent effect of MO. In the FC paradigm MO treated rats showed a dose-dependent enhancement of fear memory compared to vehicle treated rats, indicated by increased context-related freezing. Cue related fear memory remained unaffected. In the TWA paradigm MO induced a slight, but significant decrease of avoidance responses compared to vehicle treated animals, while the number of escape reactions during the acquisition of the TWA task remained unaffected. These findings expand the knowledge in the regulation of cognitive abilities and may contribute to the understanding of the contraindicative effects of MO in anxiety related mental disorders.

  6. Aversive and non-reward learning in the fire-bellied toad using familiar and unfamiliar prey stimuli

    Institute of Scientific and Technical Information of China (English)

    Ursula DICKE; Antje HEIDORN; Gerhard ROTH

    2011-01-01

    The present study investigated how snapping behavior toward familiar and unfamiliar prey is modified by reward omission and aversive conditioning in the fure-bellied toad Bombina orientalis.Toads were trained to snap at cricket images by rewarding them with live crickets.The task was learned,and the learning criterion (10 snapping responses within 2 minutes) was reached in all individuals investigated.Subsequent reward omission did not alter the frequency of snapping to the familiar cricket stimulus.Snapping decreased only in some individuals,when a mild foot shock was applied at snapping.However,at presentation of images of hitherto unfamiliar meal worms and foot-shock application at snapping to the stimulus,the majority of toads diminished snapping significantly.Snapping responses decreased more rapidly,when snapping at meal worms was not rewarded or a footshock was applied uncorrelated to the presentation of or snapping at meal worms.These results demonstrate that in toads familiarity and unfamiliarity of prey stimuli are important factors in aversive learning,because well-trained responses to familiar stimuli become immune against reward omission.Furthermore,at presentation of unfamiliar stimuli,omission of reward and uncorrelated footshock had a stronger aversive effect than correlated footshock [Current Zoology 57 (6):709-716,2011 ].

  7. A Window on the Study of Aversive Instrumental Learning: Strains, Performance, Neuroendocrine and Immunologic Systems

    Directory of Open Access Journals (Sweden)

    Caroline Cruz Oliveira

    2016-08-01

    Full Text Available The avoidance response is present in pathological anxiety and interferes with normal daily functions. The aim of this article is to shed light on performance markers of active avoidance (AA using two different rat strains, Sprague-Dawley (SD and Wistar. Specifically, good and poor performers were evaluated regarding anxiety traits exhibited in the elevated plus maze (EPM and corticosterone levels and motor activity in the open field test. In addition, the plasma levels of Interleukin-6 (IL-6, Interleukin-1Beta (IL-1beta, Nerve Growth Factor Beta (NGF-beta, Tumor Necrosis Factor-Alpha (TNF-alpha and cytokine-induced neutrophil chemoattractant 1 (CINC-1 were compared in the good and poor performers to better understand the role of the immunologic system in aversive learning. Behavioral criteria were employed to identify subpopulations of SD and Wistar rats based on their behavioral scores during a two-way AA test. The animals were tested for anxiety-like behavior in the EPM and motor activity in the open-field test. Plasma corticosterone levels were measured at the end of the avoidance test. Cytokine levels of IL-6, IL-1beta, NGF-beta, TNF-alpha and CINC-1 were measured in the plasma of the Wistar rats. Sixty-six percent of the Wistar rats and 35% of the SD rats exhibited a poor performance. This feature was associated with a decrease in anxiety-like behavior in the EPM. The poor and good performers exhibited lower levels of corticosterone compared with the control animals, which suggests that training alters corticosterone levels, thereby leading to hypocortisolism, independent of the performance. The CINC-1 levels were increased in the poor performers, which reinforces the role of immunologic system activation in learning deficits. Our study provides a better understanding of the complex interactions that underlie neuroimmune consequences and their implications for performance.

  8. Dictionary learning in visual computing

    CERN Document Server

    Zhang, Qiang

    2015-01-01

    The last few years have witnessed fast development on dictionary learning approaches for a set of visual computing tasks, largely due to their utilization in developing new techniques based on sparse representation. Compared with conventional techniques employing manually defined dictionaries, such as Fourier Transform and Wavelet Transform, dictionary learning aims at obtaining a dictionary adaptively from the data so as to support optimal sparse representation of the data. In contrast to conventional clustering algorithms like K-means, where a data point is associated with only one cluster c

  9. Instructed knowledge shapes feedback-driven aversive learning in striatum and orbitofrontal cortex, but not the amygdala.

    Science.gov (United States)

    Atlas, Lauren Y; Doll, Bradley B; Li, Jian; Daw, Nathaniel D; Phelps, Elizabeth A

    2016-05-12

    Socially-conveyed rules and instructions strongly shape expectations and emotions. Yet most neuroscientific studies of learning consider reinforcement history alone, irrespective of knowledge acquired through other means. We examined fear conditioning and reversal in humans to test whether instructed knowledge modulates the neural mechanisms of feedback-driven learning. One group was informed about contingencies and reversals. A second group learned only from reinforcement. We combined quantitative models with functional magnetic resonance imaging and found that instructions induced dissociations in the neural systems of aversive learning. Responses in striatum and orbitofrontal cortex updated with instructions and correlated with prefrontal responses to instructions. Amygdala responses were influenced by reinforcement similarly in both groups and did not update with instructions. Results extend work on instructed reward learning and reveal novel dissociations that have not been observed with punishments or rewards. Findings support theories of specialized threat-detection and may have implications for fear maintenance in anxiety.

  10. Heat perception and aversive learning in honey bees: putative involvement of the thermal/chemical sensor AmHsTRPA

    Directory of Open Access Journals (Sweden)

    Pierre eJunca

    2015-11-01

    Full Text Available The recent development of the olfactory conditioning of the sting extension response (SER has provided new insights into the mechanisms of aversive learning in honeybees. However, until now, very little information has been obtained concerning US detection and perception in this aversive conditioning. In the initial version of SER conditioning, bees learned to associate an odor CS with an electric shock US. Recently, we proposed a modified version of SER conditioning, in which thermal stimulation with a heated probe is used as US. This procedure has the advantage of allowing topical US applications virtually everywhere on the honeybee body. In this study, we made use of this possibility and mapped thermal responsiveness on the honeybee body, by measuring workers' SER after applying heat on 41 different structures. We then show that bees can learn the CS-US association even when the heat US is applied on body structures that are not prominent sensory organs, here the vertex (back of the head and the ventral abdomen. Next, we used a neuropharmalogical approach to evaluate the potential role of a recently described Transient Receptor Potential (TRP channel, HsTRPA, on peripheral heat detection by bees. First, we applied HsTRPA activators

  11. Electric shock for aversion training of jumping spiders: towards an arachnid model of avoidance learning.

    Science.gov (United States)

    Peckmezian, Tina; Taylor, Phillip W

    2015-04-01

    Electric shock is used widely as an aversive stimulus in conditioning experiments, yet little attention has been given to its physiological effects and their consequences for bioassays. In the present study, we provide a detailed characterization of how electric shock affects the mobility and behaviour of Servaea incana, a jumping spider. We begin with four mobility assays and then narrow our focus to a single effective assay with which we assess performance and behaviour. Based on our findings, we suggest a voltage range that may be employed as an aversive stimulus while minimizing decrements in physical performance and other aspects of behaviour. Additionally, we outline a novel method for constructing electric shock platforms that overcome some of the constraints of traditional methods while being highly effective and easily modifiable to suit the study animal and experimental context. Finally, as a demonstration of the viability of our aversive stimulus in a passive avoidance conditioning task, we successfully train spiders to associate a dark compartment with electric shock. Future research using electric shock as an aversive stimulus with terrestrial invertebrates such as spiders and insects may benefit from the flexible and reliable methods outlined in the present study.

  12. Potentiation of the early visual response to learned danger signals in adults and adolescents.

    Science.gov (United States)

    Levita, Liat; Howsley, Philippa; Jordan, Jeff; Johnston, Pat

    2015-02-01

    The reinforcing effects of aversive outcomes on avoidance behaviour are well established. However, their influence on perceptual processes is less well explored, especially during the transition from adolescence to adulthood. Using electroencephalography, we examined whether learning to actively or passively avoid harm can modulate early visual responses in adolescents and adults. The task included two avoidance conditions, active and passive, where two different warning stimuli predicted the imminent, but avoidable, presentation of an aversive tone. To avoid the aversive outcome, participants had to learn to emit an action (active avoidance) for one of the warning stimuli and omit an action for the other (passive avoidance). Both adults and adolescents performed the task with a high degree of accuracy. For both adolescents and adults, increased N170 event-related potential amplitudes were found for both the active and the passive warning stimuli compared with control conditions. Moreover, the potentiation of the N170 to the warning stimuli was stable and long lasting. Developmental differences were also observed; adolescents showed greater potentiation of the N170 component to danger signals. These findings demonstrate, for the first time, that learned danger signals in an instrumental avoidance task can influence early visual sensory processes in both adults and adolescents.

  13. Visual Learning in Application of Integration

    Science.gov (United States)

    Bt Shafie, Afza; Barnachea Janier, Josefina; Bt Wan Ahmad, Wan Fatimah

    Innovative use of technology can improve the way how Mathematics should be taught. It can enhance student's learning the concepts through visualization. Visualization in Mathematics refers to us of texts, pictures, graphs and animations to hold the attention of the learners in order to learn the concepts. This paper describes the use of a developed multimedia courseware as an effective tool for visual learning mathematics. The focus is on the application of integration which is a topic in Engineering Mathematics 2. The course is offered to the foundation students in the Universiti Teknologi of PETRONAS. Questionnaire has been distributed to get a feedback on the visual representation and students' attitudes towards using visual representation as a learning tool. The questionnaire consists of 3 sections: Courseware Design (Part A), courseware usability (Part B) and attitudes towards using the courseware (Part C). The results showed that students demonstrated the use of visual representation has benefited them in learning the topic.

  14. How Infants Learn About the Visual World

    OpenAIRE

    Johnson, Scott P.

    2010-01-01

    The visual world of adults consists of objects at various distances, partly occluding one another, substantial and stable across space and time. The visual world of young infants, in contrast, is often fragmented and unstable, consisting not of coherent objects but rather surfaces that move in unpredictable ways. Evidence from computational modeling and from experiments with human infants highlights three kinds of learning that contribute to infants' knowledge of the visual world: learning vi...

  15. Knockout crickets for the study of learning and memory: Dopamine receptor Dop1 mediates aversive but not appetitive reinforcement in crickets.

    Science.gov (United States)

    Awata, Hiroko; Watanabe, Takahito; Hamanaka, Yoshitaka; Mito, Taro; Noji, Sumihare; Mizunami, Makoto

    2015-11-02

    Elucidation of reinforcement mechanisms in associative learning is an important subject in neuroscience. In mammals, dopamine neurons are thought to play critical roles in mediating both appetitive and aversive reinforcement. Our pharmacological studies suggested that octopamine and dopamine neurons mediate reward and punishment, respectively, in crickets, but recent studies in fruit-flies concluded that dopamine neurons mediates both reward and punishment, via the type 1 dopamine receptor Dop1. To resolve the discrepancy between studies in different insect species, we produced Dop1 knockout crickets using the CRISPR/Cas9 system and found that they are defective in aversive learning with sodium chloride punishment but not appetitive learning with water or sucrose reward. The results suggest that dopamine and octopamine neurons mediate aversive and appetitive reinforcement, respectively, in crickets. We suggest unexpected diversity in neurotransmitters mediating appetitive reinforcement between crickets and fruit-flies, although the neurotransmitter mediating aversive reinforcement is conserved. This study demonstrates usefulness of the CRISPR/Cas9 system for producing knockout animals for the study of learning and memory.

  16. Genetic Dissection of Aversive Associative Olfactory Learning and Memory in Drosophila Larvae.

    Directory of Open Access Journals (Sweden)

    Annekathrin Widmann

    2016-10-01

    Full Text Available Memory formation is a highly complex and dynamic process. It consists of different phases, which depend on various neuronal and molecular mechanisms. In adult Drosophila it was shown that memory formation after aversive Pavlovian conditioning includes-besides other forms-a labile short-term component that consolidates within hours to a longer-lasting memory. Accordingly, memory formation requires the timely controlled action of different neuronal circuits, neurotransmitters, neuromodulators and molecules that were initially identified by classical forward genetic approaches. Compared to adult Drosophila, memory formation was only sporadically analyzed at its larval stage. Here we deconstruct the larval mnemonic organization after aversive olfactory conditioning. We show that after odor-high salt conditioning larvae form two parallel memory phases; a short lasting component that depends on cyclic adenosine 3'5'-monophosphate (cAMP signaling and synapsin gene function. In addition, we show for the first time for Drosophila larvae an anesthesia resistant component, which relies on radish and bruchpilot gene function, protein kinase C activity, requires presynaptic output of mushroom body Kenyon cells and dopamine function. Given the numerical simplicity of the larval nervous system this work offers a unique prospect for studying memory formation of defined specifications, at full-brain scope with single-cell, and single-synapse resolution.

  17. Searching for learning-dependent changes in the antennal lobe: simultaneous recording of neural activity and aversive olfactory learning in honeybees

    Directory of Open Access Journals (Sweden)

    Edith Roussel

    2010-09-01

    Full Text Available Plasticity in the honeybee brain has been studied using the appetitive olfactory conditioning of the proboscis extension reflex, in which a bee learns the association between an odor and a sucrose reward. In this framework, coupling behavioral measurements of proboscis extension and invasive recordings of neural activity has been difficult because proboscis movements usually introduce brain movements that affect physiological preparations. Here we took advantage of a new conditioning protocol, the aversive olfactory conditioning of the sting extension reflex, which does not generate this problem. We achieved the first simultaneous recordings of conditioned sting extension responses and calcium imaging of antennal lobe activity, thus revealing on-line processing of olfactory information during conditioning trials. Based on behavioral output we distinguished learners and non-learners and analyzed possible learning-dependent changes in antennal lobe activity. We did not find differences between glomerular responses to the CS+ and the CS- in learners. Unexpectedly, we found that during conditioning trials non-learners exhibited a progressive decrease in physiological responses to odors, irrespective of their valence. This effect could neither be attributed to a fitness problem nor to abnormal dye bleaching. We discuss the absence of learning-induced changes in the antennal lobe of learners and the decrease in calcium responses found in non-learners. Further studies will have to extend the search for functional plasticity related to aversive learning to other brain areas and to look on a broader range of temporal scales

  18. Dissociation of the associative and visceral sensory components of taste aversion learning by tetrodotoxin inactivation of the parabrachial nucleus in rats.

    Science.gov (United States)

    Ballesteros, M A; González, F; Morón, I; DeBrugada, I; Cándido, A; Gallo, M

    2002-04-12

    The parabrachial nucleus (PBN) has been proposed as the associative site for conditioned taste aversion. Previous evidence has shown that functional blockade of the PBN by tetrodotoxin (TTX) produces retrograde disruption of lithium-induced taste aversions in rats. However, given the PBN role in processing visceral cues and the long duration of the lithium-induced aversive effects, an interpretation based on lithium chloride processing deficits can not be ruled out. The aim of the present study was to use the unconditioned stimulus (US) pre-exposure phenomenon to explore the effect of PBN inactivation by intracerebral TTX microinjections on visceral processing. Three intraperitoneal (i.p.) lithium chloride injections (0.15 M; 2% b.w.) applied before the conditioning session, but not isotonic saline i.p. injections, interfered with the acquisition of a learned aversion to a cider vinegar solution (3%) in cannulated control rats. Bilateral PBN inactivation by TTX (10 ng) applied immediately after each LiCl injections disrupted the US pre-exposure effect, thus confirming its sensory role. However, PBN inactivation 30 min after LiCl injections did not interfere with the US pre-exposure effect, in spite of the fact that an identically timed PBN blockade after the acquisition trial disrupted the acquisition of taste aversions. These results stand for the associative role of PBN in taste aversion learning induced by lithium chloride, independent of its sensory role. It is concluded that PBN activity is required after the conditioning trial for the taste-visceral association to take place.

  19. Heat Perception and Aversive Learning in Honey Bees: Putative Involvement of the Thermal/Chemical Sensor AmHsTRPA.

    Science.gov (United States)

    Junca, Pierre; Sandoz, Jean-Christophe

    2015-01-01

    The recent development of the olfactory conditioning of the sting extension response (SER) has provided new insights into the mechanisms of aversive learning in honeybees. Until now, very little information has been gained concerning US detection and perception. In the initial version of SER conditioning, bees learned to associate an odor CS with an electric shock US. Recently, we proposed a modified version of SER conditioning, in which thermal stimulation with a heated probe is used as US. This procedure has the advantage of allowing topical US applications virtually everywhere on the honeybee body. In this study, we made use of this possibility and mapped thermal responsiveness on the honeybee body, by measuring workers' SER after applying heat on 41 different structures. We then show that bees can learn the CS-US association even when the heat US is applied on body structures that are not prominent sensory organs, here the vertex (back of the head) and the ventral abdomen. Next, we used a neuropharmalogical approach to evaluate the potential role of a recently described Transient Receptor Potential (TRP) channel, HsTRPA, on peripheral heat detection by bees. First, we applied HsTRPA activators to assess if such activation is sufficient for triggering SER. Second, we injected HsTRPA inhibitors to ask whether interfering with this TRP channel affects SER triggered by heat. These experiments suggest that HsTRPA may be involved in heat detection by bees, and represent a potential peripheral detection system in thermal SER conditioning.

  20. Learning QlikView data visualization

    CERN Document Server

    Pover, Karl

    2013-01-01

    A practical and fast-paced guide that gives you all the information you need to start developing charts from your data.Learning QlikView Data Visualization is for anybody interested in performing powerful data analysis and crafting insightful data visualization, independent of any previous knowledge of QlikView. Experience with spreadsheet software will help you understand QlikView functions.

  1. Digital media Experiences for Visual Learning

    DEFF Research Database (Denmark)

    Buhl, Mie

    2013-01-01

    Visual learning is a topic for didactic studies in all levels of educaion, brought about by an increasing use of digital meida- digital media give rise to discussions of how learning expereienes come about from various media ressources that generate new learning situations. new situations call...... for new tools and new theoretical approaches with which to understand them. the article argues that the current phase of social practices and technological development makes it difficult to disitnguish between experience with digital media and mediated experiences, because of the use of renegotiation og...... both possibilites of technology and the nature of the content it facilitates. the discussion comes in three parts: 1. the alteration of visual representations in contemporary teaching and learning brought about by digital interfaces, 2. the functions af visual experience in learning processes brought...

  2. NF-kappaB activity affects learning in aversive tasks: possible actions via modulation of the stress axis.

    Science.gov (United States)

    Lehmann, Michael L; Brachman, Rebecca A; Listwak, Samuel J; Herkenham, Miles

    2010-08-01

    The role of altered activity of nuclear factor kappaB (NF-kappaB) in specific aspects of motivated behavior and learning and memory was examined in mice lacking the p50 subunit of the NF-kappaB/rel transcription factor family. Nfkb1-deficient mice are unable to produce p50 and show specific susceptibilities to infections and inflammatory challenges, but the behavioral phenotype of such mice has been largely unexamined, owing in large part to the lack of understanding of the role of NF-kappaB in nervous system function. Here we show that Nfkb1 (p50) knockout mice more rapidly learned to find the hidden platform in the Morris water maze than did wildtype mice. The rise in plasma corticosterone levels after the maze test was greater in p50 knockout than in wildtype mice. In the less stressful Barnes maze, which tests similar kinds of spatial learning, the p50 knockout mice performed similarly to control mice. Adrenalectomy with corticosterone replacement eliminated the differences between p50 knockout and wildtype mice in the water maze. Knockout mice showed increased levels of basal anxiety in the open-field and light/dark box tests, suggesting that their enhanced escape latency in the water maze was due to activation of the stress (hypothalamic-pituitary-adrenal) axis leading to elevated corticosterone production by strongly but not mildly anxiogenic stimuli. The results suggest that, as in the immune system, p50 in the nervous system normally serves to dampen NF-kappaB-mediated intracellular activities, which are manifested physiologically through elevated stress responses to aversive stimuli and behaviorally in the facilitated escape performance in learning tasks.

  3. Juvenile hormone enhances aversive learning performance in 2-day old worker honey bees while reducing their attraction to queen mandibular pheromone.

    Science.gov (United States)

    McQuillan, H James; Nakagawa, Shinichi; Mercer, Alison R

    2014-01-01

    Previous studies have shown that exposing young worker bees (Apis mellifera) to queen mandibular pheromone (QMP) reduces their aversive learning performance, while enhancing their attraction to QMP. As QMP has been found to reduce the rate of juvenile hormone (JH) synthesis in worker bees, we examined whether aversive learning in 2-day old workers exposed to QMP from the time of adult emergence could be improved by injecting JH (10 µg in a 2 µl volume) into the haemolymph. We examined in addition, the effects of JH treatment on worker attraction to QMP, and on the levels of expression of amine receptor genes in the antennae, as well as in the mushroom bodies of the brain. We found that memory acquisition and 1-hour memory recall were enhanced by JH. In contrast, JH treatment reduced the bees' attraction towards a synthetic strip impregnated with QMP (Bee Boost). Levels of expression of the dopamine receptor gene Amdop1 were significantly lower in the mushroom bodies of JH-treated bees than in bees treated with vehicle alone (acetone diluted with bee ringer). Expression of the octopamine receptor gene, Amoa1, in this brain region was also affected by JH treatment, and in the antennae, Amoa1 transcript levels were significantly lower in JH-treated bees compared to controls. The results of this study suggest that QMP's effects on JH synthesis may contribute to reducing aversive learning performance and enhancing attraction to QMP in young worker bees.

  4. Learning Enhancement through Visual Training.

    Science.gov (United States)

    Getz, Donald J.

    1980-01-01

    A study involving 120 second-grade students with deficiencies in visual perceptual skills was designed to determine the effects of a vision training program on reading test performance. Students receiving vision training did significantly better in tests measuring reading comprehension and word recognition skills than did students who did not…

  5. Locomotor sequence learning in visually guided walking.

    Science.gov (United States)

    Choi, Julia T; Jensen, Peter; Nielsen, Jens Bo

    2016-04-01

    Voluntary limb modifications must be integrated with basic walking patterns during visually guided walking. In this study we tested whether voluntary gait modifications can become more automatic with practice. We challenged walking control by presenting visual stepping targets that instructed subjects to modify step length from one trial to the next. Our sequence learning paradigm is derived from the serial reaction-time (SRT) task that has been used in upper limb studies. Both random and ordered sequences of step lengths were used to measure sequence-specific and sequence-nonspecific learning during walking. In addition, we determined how age (i.e., healthy young adults vs. children) and biomechanical factors (i.e., walking speed) affected the rate and magnitude of locomotor sequence learning. The results showed that healthy young adults (age 24 ± 5 yr,n= 20) could learn a specific sequence of step lengths over 300 training steps. Younger children (age 6-10 yr,n= 8) had lower baseline performance, but their magnitude and rate of sequence learning were the same compared with those of older children (11-16 yr,n= 10) and healthy adults. In addition, learning capacity may be more limited at faster walking speeds. To our knowledge, this is the first study to demonstrate that spatial sequence learning can be integrated with a highly automatic task such as walking. These findings suggest that adults and children use implicit knowledge about the sequence to plan and execute leg movement during visually guided walking.

  6. Aversive Olfactory Learning and Associative Long-Term Memory in "Caenorhabditis elegans"

    Science.gov (United States)

    Amano, Hisayuki; Maruyama, Ichiro N.

    2011-01-01

    The nematode "Caenorhabditis elegans" ("C. elegans") adult hermaphrodite has 302 invariant neurons and is suited for cellular and molecular studies on complex behaviors including learning and memory. Here, we have developed protocols for classical conditioning of worms with 1-propanol, as a conditioned stimulus (CS), and hydrochloride (HCl) (pH…

  7. Learning adaptive metric for robust visual tracking.

    Science.gov (United States)

    Jiang, Nan; Liu, Wenyu; Wu, Ying

    2011-08-01

    Matching the visual appearances of the target over consecutive image frames is the most critical issue in video-based object tracking. Choosing an appropriate distance metric for matching determines its accuracy and robustness, and thus significantly influences the tracking performance. Most existing tracking methods employ fixed pre-specified distance metrics. However, this simple treatment is problematic and limited in practice, because a pre-specified metric does not likely to guarantee the closest match to be the true target of interest. This paper presents a new tracking approach that incorporates adaptive metric learning into the framework of visual object tracking. Collecting a set of supervised training samples on-the-fly in the observed video, this new approach automatically learns the optimal distance metric for more accurate matching. The design of the learned metric ensures that the closest match is very likely to be the true target of interest based on the supervised training. Such a learned metric is discriminative and adaptive. This paper substantializes this new approach in a solid case study of adaptive-metric differential tracking, and obtains a closed-form analytical solution to motion estimation and visual tracking. Moreover, this paper extends the basic linear distance metric learning method to a more powerful nonlinear kernel metric learning method. Extensive experiments validate the effectiveness of the proposed approach, and demonstrate the improved performance of the proposed new tracking method.

  8. Novelty, but not operant aversive learning, enhances Fos and Egr-1 expression in the medial prefrontal cortex and hippocampal areas of rats.

    Science.gov (United States)

    Yochiy, Angélica; Britto, Luiz R G; Hunziker, Maria H L

    2012-12-01

    Immediate early genes (IEG) are presumed to be activated in response to stress, novelty, and learning. Evidence supports the involvement of prefrontal and hippocampal areas in stress and learning, but also in the detection of novel events. This study examined whether a previous experience with shocks changes the pattern of Fos and Egr-1 expression in the medial prefrontal cortex (mPFC), the hippocampal cornus ammonis 1 (CA1), and dentate gyrus (DG) of adult male Wistar rats that learned to escape in an operant aversive test. Subjects previously exposed to inescapable footshocks that learned to escape from shocks were assigned to the treated group (EXP). Subjects from Group Novelty (NOV) rested undisturbed during treatment and also learned to escape in the test. The nonshock group (NSH) rested undisturbed in both sessions. Standard immunohistochemistry procedures were used to detect the proteins in brain sections. The results show that a previous experience with shocks changed the pattern of IEG expression, then demonstrating c-fos and egr-1 induction as experience-dependent events. Compared with NSH and EXP an enhanced Fos expression was detected in the mPFC and CA1 subfield of Group NOV, which also exhibited increased Egr-1 expression in the mPFC and DG in comparison to NSH. No differences were found in the DG for Fos, or in the CA1 for Egr-1. Novelty, and not the operant aversive escape learning, seems to have generated IEG induction. The results suggest novel stimuli as a possible confounding factor in studies on Fos and/or Egr-1 expression in aversive conditions.

  9. Learning the way to blood: first evidence of dual olfactory conditioning in a blood-sucking insect, Rhodnius prolixus. II. Aversive learning.

    Science.gov (United States)

    Vinauger, Clément; Buratti, Laura; Lazzari, Claudio R

    2011-09-15

    After having demonstrated that blood-sucking bugs are able to associate a behaviourally neutral odour (L-lactic acid) with positive reinforcement (i.e. appetitive conditioning) in the first part of this study, we tested whether these insects were also able to associate the same odour with a negative reinforcement (i.e. aversive conditioning). Learned aversion to host odours has been repeatedly suggested as a determinant for the distribution of disease vectors among host populations. Nevertheless, no experimental evidence has been obtained so far. Adapting a classical conditioning approach to our haematophagous model, we trained larvae of Rhodnius prolixus to associate L-lactic acid, an odour perceived by bugs but behaviourally neutral when presented alone, with a mechanical perturbation (i.e. negative reinforcement). Naive bugs and bugs exposed to CS, punishment, or CS and punishment without contingency remained indifferent to the presence of an air stream loaded with L-lactic acid (random orientation on a locomotion compensator), whereas the groups previously exposed to the contingency CS-punishment were significantly repelled by L-lactic acid. In a companion paper, the opposite, i.e. attraction, was induced in bugs exposed to the contingency of the same odour with a positive reinforcement. These constitute the first pieces of evidence of olfactory conditioning in triatomine bugs and the first demonstration that the same host odour can be used by insects that are disease vectors to learn to recognize either a host to feed on or a potentially defensive one. The orientation mechanism during repulsion is also discussed in light of our results.

  10. Learning Sorting Algorithms through Visualization Construction

    Science.gov (United States)

    Cetin, Ibrahim; Andrews-Larson, Christine

    2016-01-01

    Recent increased interest in computational thinking poses an important question to researchers: What are the best ways to teach fundamental computing concepts to students? Visualization is suggested as one way of supporting student learning. This mixed-method study aimed to (i) examine the effect of instruction in which students constructed…

  11. Right Hemisphere Dominance in Visual Statistical Learning

    Science.gov (United States)

    Roser, Matthew E.; Fiser, Jozsef; Aslin, Richard N.; Gazzaniga, Michael S.

    2011-01-01

    Several studies report a right hemisphere advantage for visuospatial integration and a left hemisphere advantage for inferring conceptual knowledge from patterns of covariation. The present study examined hemispheric asymmetry in the implicit learning of new visual feature combinations. A split-brain patient and normal control participants viewed…

  12. Learned image representations for visual recognition

    DEFF Research Database (Denmark)

    Larsen, Anders Boesen Lindbo

    This thesis addresses the problem of extracting image structures for representing images effectively in order to solve visual recognition tasks. Problems from diverse research areas (medical imaging, material science and food processing) have motivated large parts of the methodological development....... The solutions are inspired by and extend state-of-the-art techniques for describing and learning image content. More specifically, the thesis explores two approaches to constructing image representations, namely feature engineering and feature learning. In the feature engineering approach, we devise a new image...... the ability to learn high-level concepts in images of faces. The thesis argues in favor of learning features and presents new methods for domains with limited amounts of labeled data allowing feature learning to be applied more broadly....

  13. Visual and Verbal Learning in a Genetic Metabolic Disorder

    Science.gov (United States)

    Spilkin, Amy M.; Ballantyne, Angela O.; Trauner, Doris A.

    2009-01-01

    Visual and verbal learning in a genetic metabolic disorder (cystinosis) were examined in the following three studies. The goal of Study I was to provide a normative database and establish the reliability and validity of a new test of visual learning and memory (Visual Learning and Memory Test; VLMT) that was modeled after a widely used test of…

  14. Learning sorting algorithms through visualization construction

    Science.gov (United States)

    Cetin, Ibrahim; Andrews-Larson, Christine

    2016-01-01

    Recent increased interest in computational thinking poses an important question to researchers: What are the best ways to teach fundamental computing concepts to students? Visualization is suggested as one way of supporting student learning. This mixed-method study aimed to (i) examine the effect of instruction in which students constructed visualizations on students' programming achievement and students' attitudes toward computer programming, and (ii) explore how this kind of instruction supports students' learning according to their self-reported experiences in the course. The study was conducted with 58 pre-service teachers who were enrolled in their second programming class. They expect to teach information technology and computing-related courses at the primary and secondary levels. An embedded experimental model was utilized as a research design. Students in the experimental group were given instruction that required students to construct visualizations related to sorting, whereas students in the control group viewed pre-made visualizations. After the instructional intervention, eight students from each group were selected for semi-structured interviews. The results showed that the intervention based on visualization construction resulted in significantly better acquisition of sorting concepts. However, there was no significant difference between the groups with respect to students' attitudes toward computer programming. Qualitative data analysis indicated that students in the experimental group constructed necessary abstractions through their engagement in visualization construction activities. The authors of this study argue that the students' active engagement in the visualization construction activities explains only one side of students' success. The other side can be explained through the instructional approach, constructionism in this case, used to design instruction. The conclusions and implications of this study can be used by researchers and

  15. Transfer learning for visual categorization: a survey.

    Science.gov (United States)

    Shao, Ling; Zhu, Fan; Li, Xuelong

    2015-05-01

    Regular machine learning and data mining techniques study the training data for future inferences under a major assumption that the future data are within the same feature space or have the same distribution as the training data. However, due to the limited availability of human labeled training data, training data that stay in the same feature space or have the same distribution as the future data cannot be guaranteed to be sufficient enough to avoid the over-fitting problem. In real-world applications, apart from data in the target domain, related data in a different domain can also be included to expand the availability of our prior knowledge about the target future data. Transfer learning addresses such cross-domain learning problems by extracting useful information from data in a related domain and transferring them for being used in target tasks. In recent years, with transfer learning being applied to visual categorization, some typical problems, e.g., view divergence in action recognition tasks and concept drifting in image classification tasks, can be efficiently solved. In this paper, we survey state-of-the-art transfer learning algorithms in visual categorization applications, such as object recognition, image classification, and human action recognition.

  16. Visual quality assessment by machine learning

    CERN Document Server

    Xu, Long; Kuo, C -C Jay

    2015-01-01

    The book encompasses the state-of-the-art visual quality assessment (VQA) and learning based visual quality assessment (LB-VQA) by providing a comprehensive overview of the existing relevant methods. It delivers the readers the basic knowledge, systematic overview and new development of VQA. It also encompasses the preliminary knowledge of Machine Learning (ML) to VQA tasks and newly developed ML techniques for the purpose. Hence, firstly, it is particularly helpful to the beginner-readers (including research students) to enter into VQA field in general and LB-VQA one in particular. Secondly, new development in VQA and LB-VQA particularly are detailed in this book, which will give peer researchers and engineers new insights in VQA.

  17. Visualizing output for a data learning algorithm

    Science.gov (United States)

    Carson, Daniel; Graham, James; Ternovskiy, Igor

    2016-05-01

    This paper details the process we went through to visualize the output for our data learning algorithm. We have been developing a hierarchical self-structuring learning algorithm based around the general principles of the LaRue model. One example of a proposed application of this algorithm would be traffic analysis, chosen because it is conceptually easy to follow and there is a significant amount of already existing data and related research material with which to work with. While we choose the tracking of vehicles for our initial approach, it is by no means the only target of our algorithm. Flexibility is the end goal, however, we still need somewhere to start. To that end, this paper details our creation of the visualization GUI for our algorithm, the features we included and the initial results we obtained from our algorithm running a few of the traffic based scenarios we designed.

  18. Master's Thesis : Deep Learning for Visual Recognition

    OpenAIRE

    Cadène, Rémi; Thome, Nicolas; Cord, Matthieu

    2016-01-01

    The goal of our research is to develop methods advancing automatic visual recognition. In order to predict the unique or multiple labels associated to an image, we study different kind of Deep Neural Networks architectures and methods for supervised features learning. We first draw up a state-of-the-art review of the Convolutional Neural Networks aiming to understand the history behind this family of statistical models, the limit of modern architectures and the novel techniques currently used...

  19. Informal interprofessional learning: visualizing the clinical workplace.

    Science.gov (United States)

    Wagter, Judith Martine; van de Bunt, Gerhard; Honing, Marina; Eckenhausen, Marina; Scherpbier, Albert

    2012-05-01

    Daily collaboration of senior doctors, residents and nurses involves a major potential for sharing knowledge between professionals. Therefore, more attention needs to be paid to informal learning to create strategies and appropriate conditions for enhancing and effectuating informal learning in the workplace. The aim of this study is to visualize and describe patterns of informal interprofessional learning relations among staff in complex care. Questionnaires with four network questions - recognized as indicators of informal learning in the clinical workplace - were handed out to intensive and medium care unit (ICU/MCU) staff members (N = 108), of which 77% were completed and returned. Data were analyzed using social network analysis and Mokken scale analysis. Densities, tie strength and reciprocity of the four networks created show MCU and ICU nurses as subgroups within the ward and reveal central but relatively one-sided relations of senior doctors with nurses and residents. Based on the analyses, we formulated a scale of intensity of informal learning relations that can be used to understand and stimulate informal interprofessional learning.

  20. Learning style, judgements of learning, and learning of verbal and visual information.

    Science.gov (United States)

    Knoll, Abby R; Otani, Hajime; Skeel, Reid L; Van Horn, K Roger

    2016-09-13

    The concept of learning style is immensely popular despite the lack of evidence showing that learning style influences performance. This study tested the hypothesis that the popularity of learning style is maintained because it is associated with subjective aspects of learning, such as judgements of learning (JOLs). Preference for verbal and visual information was assessed using the revised Verbalizer-Visualizer Questionnaire (VVQ). Then, participants studied a list of word pairs and a list of picture pairs, making JOLs (immediate, delayed, and global) while studying each list. Learning was tested by cued recall. The results showed that higher VVQ verbalizer scores were associated with higher immediate JOLs for words, and higher VVQ visualizer scores were associated with higher immediate JOLs for pictures. There was no association between VVQ scores and recall or JOL accuracy. As predicted, learning style was associated with subjective aspects of learning but not objective aspects of learning.

  1. The relevance of visual information on learning sounds in infancy

    NARCIS (Netherlands)

    S.M.M. ter Schure

    2016-01-01

    Newborn infants are sensitive to combinations of visual and auditory speech. Does this ability to match sounds and sights affect how infants learn the sounds of their native language? And are visual articulations the only type of visual information that can influence sound learning? This dissertatio

  2. Learning STEM Through Integrative Visual Representations

    Science.gov (United States)

    Virk, Satyugjit Singh

    Previous cognitive models of memory have not comprehensively taken into account the internal cognitive load of chunking isolated information and have emphasized the external cognitive load of visual presentation only. Under the Virk Long Term Working Memory Multimedia Model of cognitive load, drawing from the Cowan model, students presented with integrated animations of the key neural signal transmission subcomponents where the interrelationships between subcomponents are visually and verbally explicit, were hypothesized to perform significantly better on free response and diagram labeling questions, than students presented with isolated animations of these subcomponents. This is because the internal attentional cognitive load of chunking these concepts is greatly reduced and hence the overall cognitive load is less for the integrated visuals group than the isolated group, despite the higher external load for the integrated group of having the interrelationships between subcomponents presented explicitly. Experiment 1 demonstrated that integrating the subcomponents of the neuron significantly enhanced comprehension of the interconnections between cellular subcomponents and approached significance for enhancing comprehension of the layered molecular correlates of the cellular structures and their interconnections. Experiment 2 corrected time on task confounds from Experiment 1 and focused on the cellular subcomponents of the neuron only. Results from the free response essay subcomponent subscores did demonstrate significant differences in favor of the integrated group as well as some evidence from the diagram labeling section. Results from free response, short answer and What-If (problem solving), and diagram labeling detailed interrelationship subscores demonstrated the integrated group did indeed learn the extra material they were presented with. This data demonstrating the integrated group learned the extra material they were presented with provides some initial

  3. Reduced palatability in lithium- and activity-based, but not in amphetamine-based, taste aversion learning.

    Science.gov (United States)

    Dwyer, Dominic M; Boakes, Robert A; Hayward, Andrew J

    2008-10-01

    Conditioned taste aversions (CTA) based on lithium chloride (Experiment 1), amphetamine (Experiment 2), and wheel running (Experiment 3) were examined using the analysis of the microstructure of licking to measure the palatability of the taste serving as the conditioned stimulus (CS). Pairing saccharin with amphetamine reduced saccharin intake without reducing the size of licking clusters, initial lick rate, or the distribution of inter-lick intervals (ILIs) within a cluster. By contrast, pairing saccharin with lithium or wheel-running reduced saccharin intake as well as lick cluster size, initial lick rate, and the distribution of ILIs within a cluster. As lick cluster size, initial lick rate, and ILI distribution can be used as indices of stimulus palatability, the current results indicate that taste aversions based on either lithium or activity reduced the palatability of the CS. This suggests that aversions based on both lithium and wheel running involve conditioned nausea to the CS taste. The absence of similar changes in licking microstructure with amphetamine-based CTA is consistent with other evidence indicating this does not involve nausea.

  4. Visual feature learning in artificial grammar classification.

    Science.gov (United States)

    Chang, Grace Y; Knowlton, Barbara J

    2004-05-01

    The Artificial Grammar Learning task has been used extensively to assess individuals' implicit learning capabilities. Previous work suggests that participants implicitly acquire rule-based knowledge as well as exemplar-specific knowledge in this task. This study investigated whether exemplar-specific knowledge acquired in this task is based on the visual features of the exemplars. When a change in the font and case occurred between study and test, there was no effect on sensitivity to grammatical rules in classification judgments. However, such a change did virtually eliminate sensitivity to training frequencies of letter bigrams and trigrams (chunk strength) in classification judgments. Performance of a secondary task during study eliminated this font sensitivity and generally reduced the contribution of chunk strength knowledge. The results are consistent with the idea that perceptual fluency makes a contribution to artificial grammar judgments.

  5. Perceptual Learning in Children With Visual Impairment Improves Near Visual Acuity

    NARCIS (Netherlands)

    Huurneman, Bianca; Boonstra, F. Nienke; Cox, Ralf F. A.; van Rens, Ger; Cillessen, Antonius H. N.

    2013-01-01

    PURPOSE. This study investigated whether visual perceptual learning can improve near visual acuity and reduce foveal crowding effects in four-to nine-year-old children with visual impairment. METHODS. Participants were 45 children with visual impairment and 29 children with normal vision. Children w

  6. Learning without knowing: subliminal visual feedback facilitates ballistic motor learning

    DEFF Research Database (Denmark)

    Lundbye-Jensen, Jesper; Leukel, Christian; Nielsen, Jens Bo

    During daily life we are constantly bombarded by sensory input providing information on the state of our body and the surrounding world. Although we do not consciously perceive all sensory inputs, these may nevertheless have consequences for our future behavior (e.g. Goodale and Milner...... was on the screen during learning. Despite of this, there was a significantly larger learning effect in the subliminal 13-26 ms group compared to the subliminal 0 ms group. In conclusion, the results demonstrate that in addition to supraliminal feedback, subliminal feedback, which was not consciously perceived...... by the learner, indeed facilitated ballistic motor learning. This effect likely relates to multiple (conscious versus unconscious) processing of visual feedback and to the specific neural circuitries involved in optimization of ballistic motor performance....

  7. Supporting curriculum development by visualizing a continuous learning pathway

    NARCIS (Netherlands)

    Schoonenboom, Judith; Oud, Wil

    2006-01-01

    Please, cite this publication as: Schoonenboom, J., & Oud, W. (2006). Supporting curriculum development by visualizing a continuous learning pathway. Proceedings of International Workshop in Learning Networks for Lifelong Competence Development, TENCompetence Conference. March 30th-31st, Sofia, Bulg

  8. Ambiguity aversion in rhesus macaques

    Directory of Open Access Journals (Sweden)

    Benjamin eHayden

    2010-09-01

    Full Text Available People generally prefer risky options, which have fully specified outcome probabilities, to ambiguous options, which have unspecified probabilities. This preference, formalized in economics, is strong enough that people will reliably prefer a risky option to an ambiguous option with a greater expected value. Explanations for ambiguity aversion often invoke uniquely human faculties like language, self-justification, or a desire to avoid public embarrassment. Challenging these ideas, here we demonstrate that a preference for unambiguous options is shared with rhesus macaques. We trained four monkeys to choose between pairs of options that both offered explicitly cued probabilities of large and small juice outcomes. We then introduced occasional trials where one of the options was obscured and examined their resulting preferences; we ran humans in a parallel experiment on a nearly identical task. We found that monkeys reliably preferred risky options to ambiguous ones, even when this bias was costly, closely matching the behavior of humans in the analogous task. Notably, ambiguity aversion varied parametrically with the extent of ambiguity. As expected, ambiguity aversion gradually declined as monkeys learned the underlying probability distribution of rewards. These data indicate that ambiguity aversion reflects fundamental cognitive biases shared with other animals rather than uniquely human factors guiding decisions.

  9. Computation and Learning in Visual Development

    Directory of Open Access Journals (Sweden)

    M Nardini

    2014-08-01

    Full Text Available In a special issue marking 30 years since the publication of Marr's Vision (Perception 41:9, 2012, Poggio proposed an update to Marr's influential “levels of understanding” framework. As well as understanding which algorithms are used for computations such as stereo or object recognition, we also need to understand how observers learn these algorithms, and how this learning is accomplished by neural circuits. I will describe research that addresses this problem in the domain of cue combination. In the last decade, linear cue combination has emerged as a common principle in visual and multisensory processing. In very many tasks, a computational goal (to minimise sensory uncertainty is achieved by the algorithm of weighted averaging. This framework provides a good description of observers' behaviour when combining sensory estimates (e.g. multiple depth cues. However, research has repeatedly shown that the computations carried out by developing perceptual systems – up to 8 years or later in humans – are not those leading to uncertainty reduction via weighted averaging. I will describe results showing how developing and mature perceptual systems differ in their computations when combining sensory cues, and outline two key problems for current and future research: 1. understanding the reorganisation of neural information processing that underlies these computational changes, and 2. understanding the learning mechanisms by which we acquire cue combination abilities through perceptual experience.

  10. Mechanisms of attention for appetitive and aversive outcomes in Pavlovian conditioning.

    Science.gov (United States)

    Austin, A J; Duka, T

    2010-11-12

    Different mechanisms of attention controlling learning have been proposed in appetitive and aversive conditioning. The aim of the present study was to compare attention and learning in a Pavlovian conditioning paradigm using visual stimuli of varying predictive value of either monetary reward (appetitive conditioning; 10p or 50p) or blast of white noise (aversive conditioning; 97 dB or 102 dB). Outcome values were matched across the two conditions with regard to their emotional significance. Sixty-four participants were allocated to one of the four conditions matched for age and gender. All participants underwent a discriminative learning task using pairs of visual stimuli that signalled a 100%, 50%, or 0% probability of receiving an outcome. Learning was measured using a 9-point Likert scale of expectancy of the outcome, while attention using an eyetracker device. Arousal and emotional conditioning were also evaluated. Dwell time was greatest for the full predictor in the noise groups, while in the money groups attention was greatest for the partial predictor over the other two predictors. The progression of learning was the same for both groups. These findings suggest that in aversive conditioning attention is driven by the predictive salience of the stimulus while in appetitive conditioning attention is error-driven, when emotional value of the outcome is comparable.

  11. Flexible Visual Statistical Learning: Transfer across Space and Time

    Science.gov (United States)

    Turk-Browne, Nicholas B.; Scholl, Brian J.

    2009-01-01

    The environment contains considerable information that is distributed across space and time, and the visual system is remarkably sensitive to such information via the operation of visual statistical learning (VSL). Previous VSL studies have focused on establishing what kinds of statistical relationships can be learned but have not fully explored…

  12. Extending the Engagement Taxonomy: Software Visualization and Collaborative Learning

    Science.gov (United States)

    Myller, Niko; Bednarik, Roman; Sutinen, Erkki; Ben-Ari, Mordechai

    2009-01-01

    As collaborative learning in general, and pair programming in particular, has become widely adopted in computer science education, so has the use of pedagogical visualization tools for facilitating collaboration. However, there is little theory on collaborative learning with visualization, and few studies on their effect on each other. We build on…

  13. Development of Visualization of Learning Outcomes Using Curriculum Mapping

    Science.gov (United States)

    Ikuta, Takashi; Gotoh, Yasushi

    2012-01-01

    Niigata University has started to develop the Niigata University Bachelor Assessment System (NBAS). The objective is to have groups of teachers belonging to educational programs discuss whether visualized learning outcomes are comprehensible. Discussions based on teachers' subjective judgments showed in general that visualized learning outcomes…

  14. The Effects of Realism in Learning with Dynamic Visualizations

    Science.gov (United States)

    Scheiter, Katharina; Gerjets, Peter; Huk, Thomas; Imhof, Birgit; Kammerer, Yvonne

    2009-01-01

    Two experiments are reported that investigated the relative effectiveness of a realistic dynamic visualization as opposed to a schematic visualization for learning about cell replication (mitosis). In Experiment 1, 37 university students watched either realistic or schematic visualizations. Students' subjective task demands ratings as well as…

  15. Colouring the Gaps in Learning Design: Aesthetics and the Visual in Learning

    Science.gov (United States)

    Carroll, Fiona; Kop, Rita

    2016-01-01

    The visual is a dominant mode of information retrieval and understanding however, the focus on the visual dimension of Technology Enhanced Learning (TEL) is still quite weak in relation to its predominant focus on usability. To accommodate the future needs of the visual learner, designers of e-learning environments should advance the current…

  16. Self-paced model learning for robust visual tracking

    Science.gov (United States)

    Huang, Wenhui; Gu, Jason; Ma, Xin; Li, Yibin

    2017-01-01

    In visual tracking, learning a robust and efficient appearance model is a challenging task. Model learning determines both the strategy and the frequency of model updating, which contains many details that could affect the tracking results. Self-paced learning (SPL) has recently been attracting considerable interest in the fields of machine learning and computer vision. SPL is inspired by the learning principle underlying the cognitive process of humans, whose learning process is generally from easier samples to more complex aspects of a task. We propose a tracking method that integrates the learning paradigm of SPL into visual tracking, so reliable samples can be automatically selected for model learning. In contrast to many existing model learning strategies in visual tracking, we discover the missing link between sample selection and model learning, which are combined into a single objective function in our approach. Sample weights and model parameters can be learned by minimizing this single objective function. Additionally, to solve the real-valued learning weight of samples, an error-tolerant self-paced function that considers the characteristics of visual tracking is proposed. We demonstrate the robustness and efficiency of our tracker on a recent tracking benchmark data set with 50 video sequences.

  17. Jointly Learning Visually Correlated Dictionaries for Large-Scale Visual Recognition Applications.

    Science.gov (United States)

    Ning Zhou; Jianping Fan

    2014-04-01

    Learning discriminative dictionaries for image content representation plays a critical role in visual recognition. In this paper, we present a joint dictionary learning (JDL) algorithm which exploits the inter-category visual correlations to learn more discriminative dictionaries. Given a group of visually correlated categories, JDL simultaneously learns one common dictionary and multiple category-specific dictionaries to explicitly separate the shared visual atoms from the category-specific ones. The problem of JDL is formulated as a joint optimization with a discrimination promotion term according to the Fisher discrimination criterion. A visual tree method is developed to cluster a large number of categories into a set of disjoint groups, so that each of them contains a reasonable number of visually correlated categories. The process of image category clustering helps JDL to learn better dictionaries for classification by ensuring that the categories in the same group are of strong visual correlations. Also, it makes JDL to be computationally affordable in large-scale applications. Three classification schemes are adopted to make full use of the dictionaries learned by JDL for visual content representation in the task of image categorization. The effectiveness of the proposed algorithms has been evaluated using two image databases containing 17 and 1,000 categories, respectively.

  18. Complexity and competition in appetitive and aversive neural circuits

    Directory of Open Access Journals (Sweden)

    Crista L. Barberini

    2012-11-01

    Full Text Available Decision-making often involves using sensory cues to predict possible rewarding or punishing reinforcement outcomes before selecting a course of action. Recent work has revealed complexity in how the brain learns to predict rewards and punishments. Analysis of neural signaling during and after learning in the amygdala and orbitofrontal cortex, two brain areas that process appetitive and aversive stimuli, reveals a dynamic relationship between appetitive and aversive circuits. Specifically, the relationship between signaling in appetitive and aversive circuits in these areas shifts as a function of learning. Furthermore, although appetitive and aversive circuits may often drive opposite behaviors – approaching or avoiding reinforcement depending upon its valence – these circuits can also drive similar behaviors, such as enhanced arousal or attention; these processes also may influence choice behavior. These data highlight the formidable challenges ahead in dissecting how appetitive and aversive neural circuits interact to produce a complex and nuanced range of behaviors.

  19. Implicit learning increases preference for predictive visual display.

    Science.gov (United States)

    Ogawa, Hirokazu; Watanabe, Katsumi

    2011-08-01

    We investigated whether implicit learning in a visual search task would influence preferences for visual stimuli. Participants performed a contextual cueing task in which they searched for visual targets, the locations of which were either predicted or not predicted by the positioning of distractors. The speed with which participants located the targets increased across trials more rapidly for predictive displays than for non-predictive displays, consistent with contextual cueing. Participants were subsequently asked to rate the "goodness" of visual displays. The rating results showed that they preferred predictive displays to both non-predictive and novel displays. The participants did not recognize predictive displays any more frequently than they did non-predictive or novel displays. These results suggest that contextual cueing occurred implicitly and that the implicit learning of visual layouts promotes a preference for visual layouts that are predictive of target location.

  20. Mining visual collocation patterns via self-supervised subspace learning.

    Science.gov (United States)

    Yuan, Junsong; Wu, Ying

    2012-04-01

    Traditional text data mining techniques are not directly applicable to image data which contain spatial information and are characterized by high-dimensional visual features. It is not a trivial task to discover meaningful visual patterns from images because the content variations and spatial dependence in visual data greatly challenge most existing data mining methods. This paper presents a novel approach to coping with these difficulties for mining visual collocation patterns. Specifically, the novelty of this work lies in the following new contributions: 1) a principled solution to the discovery of visual collocation patterns based on frequent itemset mining and 2) a self-supervised subspace learning method to refine the visual codebook by feeding back discovered patterns via subspace learning. The experimental results show that our method can discover semantically meaningful patterns efficiently and effectively.

  1. Learning from Chemical Visualizations: Comparing Generation and Selection

    Science.gov (United States)

    Zhang, Zhihui Helen; Linn, Marcia C.

    2013-01-01

    Dynamic visualizations can make unseen phenomena such as chemical reactions visible but students need guidance to benefit from them. This study explores the value of generating drawings versus selecting among alternatives to guide students to learn chemical reactions from a dynamic visualization of hydrogen combustion as part of an online inquiry…

  2. Attentional Modulation in Visual Cortex Is Modified during Perceptual Learning

    Science.gov (United States)

    Bartolucci, Marco; Smith, Andrew T.

    2011-01-01

    Practicing a visual task commonly results in improved performance. Often the improvement does not transfer well to a new retinal location, suggesting that it is mediated by changes occurring in early visual cortex, and indeed neuroimaging and neurophysiological studies both demonstrate that perceptual learning is associated with altered activity…

  3. Images in Language: Metaphors and Metamorphoses. Visual Learning. Volume 1

    Science.gov (United States)

    Benedek, Andras, Ed.; Nyiri, Kristof, Ed.

    2011-01-01

    Learning and teaching are faced with radically new challenges in today's rapidly changing world and its deeply transformed communicational environment. We are living in an era of images. Contemporary visual technology--film, video, interactive digital media--is promoting but also demanding a new approach to education: the age of visual learning…

  4. Visual teaching and learning in the fields of engineering

    Directory of Open Access Journals (Sweden)

    Kyvete S. Shatri

    2015-11-01

    Full Text Available Engineering education today is faced with numerous demands that are closely connected with a globalized economy. One of these requirements is to draw the engineers of the future, who are characterized with: strong analytical skills, creativity, ingenuity, professionalism, intercultural communication and leadership. To achieve this effective teaching methods should be used to facilitate and enhance the learning of students and their performance in general, making them able to cope with market demands of a globalized economy. One of these methods is the visualization as a very important method that increases the learning of students. A visual approach in science and in engineering also increases communication, critical thinking and provides analytical approach to various problems. Therefore, this research is aimed to investigate the effect of the use of visualization in the process of teaching and learning in engineering fields and encourage teachers and students to use visual methods for teaching and learning. The results of this research highlight the positive effect that the use of visualization has in the learning process of students and their overall performance. In addition, innovative teaching methods have a good effect in the improvement of the situation. Visualization motivates students to learn, making them more cooperative and developing their communication skills.

  5. Tool-Based Curricula and Visual Learning

    Directory of Open Access Journals (Sweden)

    Dragica Vasileska

    2013-12-01

    Full Text Available In the last twenty years nanotechnology hasrevolutionized the world of information theory, computers andother important disciplines, such as medicine, where it hascontributed significantly in the creation of more sophisticateddiagnostic tools. Therefore, it is important for people working innanotechnology to better understand basic concepts to be morecreative and productive. To further foster the progress onNanotechnology in the USA, the National Science Foundation hascreated the Network for Computational Nanotechnology (NCNand the dissemination of all the information from member andnon-member participants of the NCN is enabled by thecommunity website www.nanoHUB.org. nanoHUB’s signatureservices online simulation that enables the operation ofsophisticated research and educational simulation engines with acommon browser. No software installation or local computingpower is needed. The simulation tools as well as nano-conceptsare augmented by educational materials, assignments, and toolbasedcurricula, which are assemblies of tools that help studentsexcel in a particular area.As elaborated later in the text, it is the visual mode of learningthat we are exploiting in achieving faster and better results withstudents that go through simulation tool-based curricula. Thereare several tool based curricula already developed on thenanoHUB and undergoing further development, out of which fiveare directly related to nanoelectronics. They are: ABACUS –device simulation module; ACUTE – Computational Electronicsmodule; ANTSY – bending toolkit; and AQME – quantummechanics module. The methodology behind tool-based curriculais discussed in details. Then, the current status of each module ispresented, including user statistics and student learningindicatives. Particular simulation tool is explored further todemonstrate the ease by which students can grasp information.Representative of Abacus is PN-Junction Lab; representative ofAQME is PCPBT tool; and

  6. The Contribution of Visualization to Learning Computer Architecture

    Science.gov (United States)

    Yehezkel, Cecile; Ben-Ari, Mordechai; Dreyfus, Tommy

    2007-01-01

    This paper describes a visualization environment and associated learning activities designed to improve learning of computer architecture. The environment, EasyCPU, displays a model of the components of a computer and the dynamic processes involved in program execution. We present the results of a research program that analysed the contribution of…

  7. Visual Descriptor Learning for Predicting Grasping Affordances

    DEFF Research Database (Denmark)

    Thomsen, Mikkel Tang

    2016-01-01

    consisting of surface features was performed. Dimensions in the visual space were varied and the effects were evaluated with the task of grasping unknown object. The evaluation was performed using a novel probabilistic grasp prediction approach based on neighbourhood analysis. The resulting success...... by the task of grasping unknown objects given visual sensor information. The contributions from this thesis stem from three works that all relate to the task of grasping unknown objects but with particular focus on the visual representation part of the problem. First an investigation of a visual feature space......-rates for predicting grasps were between 75% and 90% depending on the object class. The investigations also provided insights into the importance of selecting a proper visual feature space when utilising it for predicting affordances. As a consequence of the gained insights, a semi-local surface feature, the Sliced...

  8. Visual associative learning in restrained honey bees with intact antennae.

    Directory of Open Access Journals (Sweden)

    Scott E Dobrin

    Full Text Available A restrained honey bee can be trained to extend its proboscis in response to the pairing of an odor with a sucrose reward, a form of olfactory associative learning referred to as the proboscis extension response (PER. Although the ability of flying honey bees to respond to visual cues is well-established, associative visual learning in restrained honey bees has been challenging to demonstrate. Those few groups that have documented vision-based PER have reported that removing the antennae prior to training is a prerequisite for learning. Here we report, for a simple visual learning task, the first successful performance by restrained honey bees with intact antennae. Honey bee foragers were trained on a differential visual association task by pairing the presentation of a blue light with a sucrose reward and leaving the presentation of a green light unrewarded. A negative correlation was found between age of foragers and their performance in the visual PER task. Using the adaptations to the traditional PER task outlined here, future studies can exploit pharmacological and physiological techniques to explore the neural circuit basis of visual learning in the honey bee.

  9. Closed-Loop Learning of Visual Control Policies

    CERN Document Server

    Jodogne, S R; 10.1613/jair.2110

    2011-01-01

    In this paper we present a general, flexible framework for learning mappings from images to actions by interacting with the environment. The basic idea is to introduce a feature-based image classifier in front of a reinforcement learning algorithm. The classifier partitions the visual space according to the presence or absence of few highly informative local descriptors that are incrementally selected in a sequence of attempts to remove perceptual aliasing. We also address the problem of fighting overfitting in such a greedy algorithm. Finally, we show how high-level visual features can be generated when the power of local descriptors is insufficient for completely disambiguating the aliased states. This is done by building a hierarchy of composite features that consist of recursive spatial combinations of visual features. We demonstrate the efficacy of our algorithms by solving three visual navigation tasks and a visual version of the classical Car on the Hill control problem.

  10. Context generalization in Drosophila visual learning requires the mushroom bodies

    Science.gov (United States)

    Liu, Li; Wolf, Reinhard; Ernst, Roman; Heisenberg, Martin

    1999-08-01

    The world is permanently changing. Laboratory experiments on learning and memory normally minimize this feature of reality, keeping all conditions except the conditioned and unconditioned stimuli as constant as possible. In the real world, however, animals need to extract from the universe of sensory signals the actual predictors of salient events by separating them from non-predictive stimuli (context). In principle, this can be achieved ifonly those sensory inputs that resemble the reinforcer in theirtemporal structure are taken as predictors. Here we study visual learning in the fly Drosophila melanogaster, using a flight simulator,, and show that memory retrieval is, indeed, partially context-independent. Moreover, we show that the mushroom bodies, which are required for olfactory but not visual or tactile learning, effectively support context generalization. In visual learning in Drosophila, it appears that a facilitating effect of context cues for memory retrieval is the default state, whereas making recall context-independent requires additional processing.

  11. Loss Aversion and Individual Characteristics

    DEFF Research Database (Denmark)

    Hjorth, Katrine; Fosgerau, Mogens

    2011-01-01

    Many studies have shown that loss aversion affects the valuation of non-market goods. Using stated choice data, this paper presents an empirical investigation of how individual-level loss aversion varies with observable personal characteristics and with the choice context. We investigate loss...... aversion with respect to travel time and money, and find significant loss aversion in both dimensions. The degree of loss aversion in the time dimension is larger than in the money dimension, and depends on age and education. Subjects tend to be more loss averse when the reference is well established....

  12. The medial orbitofrontal cortex encodes a general unsigned value signal during anticipation of both appetitive and aversive events.

    Science.gov (United States)

    Metereau, Elise; Dreher, Jean-Claude

    2015-02-01

    The medial orbitofrontal cortex (mOFC)/ventromedial prefrontal cortex (vmPFC) has been proposed to signal the expected value of rewards when learning stimuli-rewards associations. Yet, it is still unclear whether identical or distinct orbitofrontal cortex regions encode expected rewards and punishments at the time of the cue during appetitive and aversive classical conditioning. Moreover, it is unknown whether anticipation of different types of positive and negative reinforcers differentially influence specific orbitofrontal cortex regions. To answer these questions, this study investigated whether the human mOFC/vmPFC region encodes a general unsigned anticipatory value signal for different types of rewards and punishments (responding in a positive fashion in anticipation of both appetitive and aversive events) or a signed expected value signal (responding positively in anticipation of rewards and negatively in anticipation of punishments) when learning cue-outcomes associations. Using a model-based fMRI approach implementing a reinforcement learning model to compute the expected values of two types of rewards (pleasant juice, monetary gain) and two types of punishments (aversive juice, aversive picture), we found that mOFC/vmPFC activity correlated positively with the expected value of the cues, in anticipation of both rewards and punishments. This finding indicates that the mOFC/vmPFC encodes a general unsigned anticipatory value signal, regardless of reinforcers valence (positive/negative) and types (gustatory, visual).

  13. Visual Feature Learning in Artificial Grammar Classification

    Science.gov (United States)

    Chang, Grace Y.; Knowlton, Barbara J.

    2004-01-01

    The Artificial Grammar Learning task has been used extensively to assess individuals' implicit learning capabilities. Previous work suggests that participants implicitly acquire rule-based knowledge as well as exemplar-specific knowledge in this task. This study investigated whether exemplar-specific knowledge acquired in this task is based on the…

  14. Locomotor sequence learning in visually guided walking

    DEFF Research Database (Denmark)

    Choi, Julia T; Jensen, Peter; Nielsen, Jens Bo

    2016-01-01

    at faster walking speeds. To our knowledge, this is the first study to demonstrate that spatial sequence learning can be integrated with a highly automatic task like walking. These findings suggest that adults and children use implicit knowledge about the sequence to plan and execute leg movement during...... walking. In addition, we determined how age (i.e., healthy young adults vs. children) and biomechanical factors (i.e., walking speed) affected the rate and magnitude of locomotor sequence learning. The results showed that healthy young adults (age 24 ± 5 years, N = 20) could learn a specific sequence...... of step lengths over 300 training steps. Younger children (age 6-10 years, N = 8) have lower baseline performance, but their magnitude and rate of sequence learning was the same compared to older children (11-16 years, N = 10) and healthy adults. In addition, learning capacity may be more limited...

  15. Audiovisual Association Learning in the Absence of Primary Visual Cortex.

    Science.gov (United States)

    Seirafi, Mehrdad; De Weerd, Peter; Pegna, Alan J; de Gelder, Beatrice

    2015-01-01

    Learning audiovisual associations is mediated by the primary cortical areas; however, recent animal studies suggest that such learning can take place even in the absence of the primary visual cortex. Other studies have demonstrated the involvement of extra-geniculate pathways and especially the superior colliculus (SC) in audiovisual association learning. Here, we investigated such learning in a rare human patient with complete loss of the bilateral striate cortex. We carried out an implicit audiovisual association learning task with two different colors of red and purple (the latter color known to minimally activate the extra-genicular pathway). Interestingly, the patient learned the association between an auditory cue and a visual stimulus only when the unseen visual stimulus was red, but not when it was purple. The current study presents the first evidence showing the possibility of audiovisual association learning in humans with lesioned striate cortex. Furthermore, in line with animal studies, it supports an important role for the SC in audiovisual associative learning.

  16. Multisensory Training can Promote or Impede Visual Perceptual Learning of Speech Stimuli: Visual-Tactile versus Visual-Auditory Training

    Directory of Open Access Journals (Sweden)

    Silvio P Eberhardt

    2014-10-01

    Full Text Available In a series of studies we have been investigating how multisensory training affects unisensory perceptual learning with speech stimuli. Previously, we reported that Aaudiovisual training with speech stimuli can promote auditory-only perceptual learning in normal-hearing adults but can impede learning in congenitally deaf adults with late-acquired cochlear implants. Here, impeder and promoter effects were sought in normal-hearing adults who participated in lipreading training. In Experiment 1, visual-only (VO training on paired associations between CVCVC nonsense word videos and nonsense pictures demonstrated that VO words could be learned to a high level of accuracy even by poor lipreaders. In Experiment 2, visual-auditory (VA training in the same paradigm but with the addition of synchronous vocoded acoustic speech impeded VO learning of the stimuli in the paired-associates paradigm. In Experiment 3, the vocoded auditory-only (AO stimuli were shown to be less informative than the VO speech. Experiment 4 combined vibrotactile speech stimuli with the visual stimuli during training. Vibrotactile stimuli were shown to promote visual perceptual learning in participants whose training scores were similar. In Experiment 5, no-training controls were used to show that training with visual speech carried over to consonant identification of untrained CVCVC stimuli but not to lipreading words in sentences. Across this and previous studies, multisensory training effects depended on the functional relationship between pathways engaged during training. Two principles are proposed to account for stimulus effects: (1 Stimuli presented to the trainee’s primary perceptual pathway will impede learning by a lower-rank pathway. (2 Stimuli presented to the trainee’s lower rank perceptual pathway will promote learning by a higher-rank pathway. The mechanisms supporting these principles are discussed in light of multisensory reverse hierarchy theory.

  17. Fragment-based learning of visual object categories.

    Science.gov (United States)

    Hegdé, Jay; Bart, Evgeniy; Kersten, Daniel

    2008-04-22

    When we perceive a visual object, we implicitly or explicitly associate it with a category we know. It is known that the visual system can use local, informative image fragments of a given object, rather than the whole object, to classify it into a familiar category. How we acquire informative fragments has remained unclear. Here, we show that human observers acquire informative fragments during the initial learning of categories. We created new, but naturalistic, classes of visual objects by using a novel "virtual phylogenesis" (VP) algorithm that simulates key aspects of how biological categories evolve. Subjects were trained to distinguish two of these classes by using whole exemplar objects, not fragments. We hypothesized that if the visual system learns informative object fragments during category learning, then subjects must be able to perform the newly learned categorization by using only the fragments as opposed to whole objects. We found that subjects were able to successfully perform the classification task by using each of the informative fragments by itself, but not by using any of the comparable, but uninformative, fragments. Our results not only reveal that novel categories can be learned by discovering informative fragments but also introduce and illustrate the use of VP as a versatile tool for category-learning research.

  18. Hyperspecificity in Visual Implicit Learning: Learning of Spatial Layout Is Contingent on Item Identity

    Science.gov (United States)

    Jiang, Yuhong; Song, Joo-Hyun

    2005-01-01

    Humans conduct visual search faster when the same display is presented for a 2nd time, showing implicit learning of repeated displays. This study examines whether learning of a spatial layout transfers to other layouts that are occupied by items of new shapes or colors. The authors show that spatial context learning is sometimes contingent on item…

  19. Visual and Spatial Modes in Science Learning

    Science.gov (United States)

    Ramadas, Jayashree

    2009-01-01

    This paper surveys some major trends from research on visual and spatial thinking coming from cognitive science, developmental psychology, science literacy, and science studies. It explores the role of visualisation in creativity, in building mental models, and in the communication of scientific ideas, in order to place these findings in the…

  20. Visual discrimination learning with an iPad-equipped apparatus.

    Science.gov (United States)

    Leising, Kenneth J; Wolf, Joshua E; Ruprecht, Chad M

    2013-02-01

    Visual discrimination tasks are commonly used to assess visual learning and memory in non-human animals. The current experiments explored the suitability of an iPad (Apple, Cupertino, California), as a low-cost alternative touchscreen for visual discrimination tasks. In Experiment 1, rats were trained with patterned black-and-white stimuli in a successive non-match to sample procedure. Rats successfully interacted with the iPad but failed to learn to withhold responding on trials in which the sample matched the comparison. Experiment 2 used the same patterned stimuli, but the procedure was simplified to a successive discrimination procedure and we explored the use of procedures known to facilitate discrimination learning. Rats that received training with differential outcomes and a differential reinforcement of other behavior schedule successfully acquired the task. In Experiment 3, the same rats were tested in a simultaneous discrimination task and we explored the use of a correction and non-correction method during acquisition. Rats that failed to learn the discrimination in the previous experiment, improved while trained with the correction method. These experiments support the use of the iPad in visual discrimination tasks and inform future studies investigating learning and memory within a touchscreen-equipped (iPad or other) apparatus.

  1. A feedback neural circuit for calibrating aversive memory strength.

    Science.gov (United States)

    Ozawa, Takaaki; Ycu, Edgar A; Kumar, Ashwani; Yeh, Li-Feng; Ahmed, Touqeer; Koivumaa, Jenny; Johansen, Joshua P

    2017-01-01

    Aversive experiences powerfully regulate memory formation, and memory strength is proportional to the intensity of these experiences. Inhibition of the neural circuits that convey aversive signals when they are predicted by other sensory stimuli is hypothesized to set associative memory strength. However, the neural circuit mechanisms that produce this predictive inhibition to regulate memory formation are unknown. Here we show that predictive sensory cues recruit a descending feedback circuit from the central amygdala that activates a specific population of midbrain periaqueductal gray pain-modulatory neurons to control aversive memory strength. Optogenetic inhibition of this pathway disinhibited predicted aversive responses in lateral amygdala neurons, which store fear memories, resulting in the resetting of fear learning levels. These results reveal a control mechanism for calibrating learning signals to adaptively regulate the strength of behavioral learning. Dysregulation of this circuit could contribute to psychiatric disorders associated with heightened fear responsiveness.

  2. Deep Learning Driven Visual Path Prediction From a Single Image

    Science.gov (United States)

    Huang, Siyu; Li, Xi; Zhang, Zhongfei; He, Zhouzhou; Wu, Fei; Liu, Wei; Tang, Jinhui; Zhuang, Yueting

    2016-12-01

    Capabilities of inference and prediction are significant components of visual systems. In this paper, we address an important and challenging task of them: visual path prediction. Its goal is to infer the future path for a visual object in a static scene. This task is complicated as it needs high-level semantic understandings of both the scenes and motion patterns underlying video sequences. In practice, cluttered situations have also raised higher demands on the effectiveness and robustness of the considered models. Motivated by these observations, we propose a deep learning framework which simultaneously performs deep feature learning for visual representation in conjunction with spatio-temporal context modeling. After that, we propose a unified path planning scheme to make accurate future path prediction based on the analytic results of the context models. The highly effective visual representation and deep context models ensure that our framework makes a deep semantic understanding of the scene and motion pattern, consequently improving the performance of the visual path prediction task. In order to comprehensively evaluate the model's performance on the visual path prediction task, we construct two large benchmark datasets from the adaptation of video tracking datasets. The qualitative and quantitative experimental results show that our approach outperforms the existing approaches and owns a better generalization capability.

  3. Appetitive vs. Aversive Conditioning in Humans

    Directory of Open Access Journals (Sweden)

    Marta eAndreatta

    2015-05-01

    Full Text Available In classical conditioning, an initially neutral stimulus (conditioned stimulus, CS becomes associated with a biologically salient event (unconditioned stimulus, US, which might be pain (aversive conditioning or food (appetitive conditioning. After a few associations, the CS is able to initiate either defensive or consummatory responses, respectively. Contrary to aversive conditioning, appetitive conditioning is rarely investigated in humans, although its importance for normal and pathological behaviors (e.g., obesity, addiction is undeniable. The present study intents to translate animal findings on appetitive conditioning to humans using food as an US. Thirty-three participants were investigated between 8 am and 10 am without breakfast in order to assure that they felt hungry. During two acquisition phases, one geometrical shape (avCS+ predicted an aversive US (painful electric shock, another shape (appCS+ predicted an appetitive US (chocolate or salty pretzel according to the participants’ preference, and a third shape (CS- predicted neither US. In an extinction phase, these three shapes plus a novel shape (NEW were presented again without US delivery. Valence and arousal ratings as well as startle and skin conductance (SCR responses were collected as learning indices. We found successful aversive and appetitive conditioning. On the one hand, the avCS+ was rated as more negative and more arousing than the CS- and induced startle potentiation and enhanced SCR. On the other hand, the appCS+ was rated more positive than the CS- and induced startle attenuation and larger SCR. In summary, we successfully confirmed animal findings in (hungry humans by demonstrating appetitive learning and normal aversive learning

  4. Motor sequence learning occurs despite disrupted visual and proprioceptive feedback

    Directory of Open Access Journals (Sweden)

    Boyd Lara A

    2008-07-01

    Full Text Available Abstract Background Recent work has demonstrated the importance of proprioception for the development of internal representations of the forces encountered during a task. Evidence also exists for a significant role for proprioception in the execution of sequential movements. However, little work has explored the role of proprioceptive sensation during the learning of continuous movement sequences. Here, we report that the repeated segment of a continuous tracking task can be learned despite peripherally altered arm proprioception and severely restricted visual feedback regarding motor output. Methods Healthy adults practiced a continuous tracking task over 2 days. Half of the participants experienced vibration that altered proprioception of shoulder flexion/extension of the active tracking arm (experimental condition and half experienced vibration of the passive resting arm (control condition. Visual feedback was restricted for all participants. Retention testing was conducted on a separate day to assess motor learning. Results Regardless of vibration condition, participants learned the repeated segment demonstrated by significant improvements in accuracy for tracking repeated as compared to random continuous movement sequences. Conclusion These results suggest that with practice, participants were able to use residual afferent information to overcome initial interference of tracking ability related to altered proprioception and restricted visual feedback to learn a continuous motor sequence. Motor learning occurred despite an initial interference of tracking noted during acquisition practice.

  5. Per-Sample Multiple Kernel Approach for Visual Concept Learning

    Directory of Open Access Journals (Sweden)

    Ling-Yu Duan

    2010-01-01

    Full Text Available Learning visual concepts from images is an important yet challenging problem in computer vision and multimedia research areas. Multiple kernel learning (MKL methods have shown great advantages in visual concept learning. As a visual concept often exhibits great appearance variance, a canonical MKL approach may not generate satisfactory results when a uniform kernel combination is applied over the input space. In this paper, we propose a per-sample multiple kernel learning (PS-MKL approach to take into account intraclass diversity for improving discrimination. PS-MKL determines sample-wise kernel weights according to kernel functions and training samples. Kernel weights as well as kernel-based classifiers are jointly learned. For efficient learning, PS-MKL employs a sample selection strategy. Extensive experiments are carried out over three benchmarking datasets of different characteristics including Caltech101, WikipediaMM, and Pascal VOC'07. PS-MKL has achieved encouraging performance, comparable to the state of the art, which has outperformed a canonical MKL.

  6. Per-Sample Multiple Kernel Approach for Visual Concept Learning

    Directory of Open Access Journals (Sweden)

    Tian Yonghong

    2010-01-01

    Full Text Available Abstract Learning visual concepts from images is an important yet challenging problem in computer vision and multimedia research areas. Multiple kernel learning (MKL methods have shown great advantages in visual concept learning. As a visual concept often exhibits great appearance variance, a canonical MKL approach may not generate satisfactory results when a uniform kernel combination is applied over the input space. In this paper, we propose a per-sample multiple kernel learning (PS-MKL approach to take into account intraclass diversity for improving discrimination. PS-MKL determines sample-wise kernel weights according to kernel functions and training samples. Kernel weights as well as kernel-based classifiers are jointly learned. For efficient learning, PS-MKL employs a sample selection strategy. Extensive experiments are carried out over three benchmarking datasets of different characteristics including Caltech101, WikipediaMM, and Pascal VOC'07. PS-MKL has achieved encouraging performance, comparable to the state of the art, which has outperformed a canonical MKL.

  7. Speech Analysis and Visual Image: Language Learning

    Science.gov (United States)

    Loo, Alfred; Chung, C. W.; Lam, Alan

    2016-01-01

    Students will speak a second language with an accent if they learn the language after the age of six. It does not matter how motivated and clever they are, the accent will not go away. Only a few gifted students can speak a second language flawlessly. The exact reasons for this phenomenon are unknown. Although a large number of hypotheses have…

  8. Visual word learning in adults with dyslexia

    Directory of Open Access Journals (Sweden)

    Rosa Kit Wan Kwok

    2014-05-01

    Full Text Available We investigated word learning in university and college students with a diagnosis of dyslexia and in typically-reading controls. Participants read aloud short (4-letter and longer (7-letter nonwords as quickly as possible. The nonwords were repeated across 10 blocks, using a different random order in each block. Participants returned 7 days later and repeated the experiment. Accuracy was high in both groups. The dyslexics were substantially slower than the controls at reading the nonwords throughout the experiment. They also showed a larger length effect, indicating less effective decoding skills. Learning was demonstrated by faster reading of the nonwords across repeated presentations and by a reduction in the difference in reading speeds between shorter and longer nonwords. The dyslexics required more presentations of the nonwords before the length effect became non-significant, only showing convergence in reaction times between shorter and longer items in the second testing session where controls achieved convergence part-way through the first session. Participants also completed a psychological test battery assessing reading and spelling, vocabulary, phonological awareness, working memory, nonverbal ability and motor speed. The dyslexics performed at a similar level to the controls on nonverbal ability but significantly less well on all the other measures. Regression analyses found that decoding ability, measured as the speed of reading aloud nonwords when they were presented for the first time, was predicted by a composite of word reading and spelling scores (‘literacy’. Word learning was assessed in terms of the improvement in naming speeds over 10 blocks of training. Learning was predicted by vocabulary and working memory scores, but not by literacy, phonological awareness, nonverbal ability or motor speed. The results show that young dyslexic adults have problems both in pronouncing novel words and in learning new written words.

  9. Learning to Predict Sequences of Human Visual Fixations.

    Science.gov (United States)

    Jiang, Ming; Boix, Xavier; Roig, Gemma; Xu, Juan; Van Gool, Luc; Zhao, Qi

    2016-06-01

    Most state-of-the-art visual attention models estimate the probability distribution of fixating the eyes in a location of the image, the so-called saliency maps. Yet, these models do not predict the temporal sequence of eye fixations, which may be valuable for better predicting the human eye fixations, as well as for understanding the role of the different cues during visual exploration. In this paper, we present a method for predicting the sequence of human eye fixations, which is learned from the recorded human eye-tracking data. We use least-squares policy iteration (LSPI) to learn a visual exploration policy that mimics the recorded eye-fixation examples. The model uses a different set of parameters for the different stages of visual exploration that capture the importance of the cues during the scanpath. In a series of experiments, we demonstrate the effectiveness of using LSPI for combining multiple cues at different stages of the scanpath. The learned parameters suggest that the low-level and high-level cues (semantics) are similarly important at the first eye fixation of the scanpath, and the contribution of high-level cues keeps increasing during the visual exploration. Results show that our approach obtains the state-of-the-art performances on two challenging data sets: 1) OSIE data set and 2) MIT data set.

  10. Perceptual learning modifies the functional specializations of visual cortical areas.

    Science.gov (United States)

    Chen, Nihong; Cai, Peng; Zhou, Tiangang; Thompson, Benjamin; Fang, Fang

    2016-05-17

    Training can improve performance of perceptual tasks. This phenomenon, known as perceptual learning, is strongest for the trained task and stimulus, leading to a widely accepted assumption that the associated neuronal plasticity is restricted to brain circuits that mediate performance of the trained task. Nevertheless, learning does transfer to other tasks and stimuli, implying the presence of more widespread plasticity. Here, we trained human subjects to discriminate the direction of coherent motion stimuli. The behavioral learning effect substantially transferred to noisy motion stimuli. We used transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) to investigate the neural mechanisms underlying the transfer of learning. The TMS experiment revealed dissociable, causal contributions of V3A (one of the visual areas in the extrastriate visual cortex) and MT+ (middle temporal/medial superior temporal cortex) to coherent and noisy motion processing. Surprisingly, the contribution of MT+ to noisy motion processing was replaced by V3A after perceptual training. The fMRI experiment complemented and corroborated the TMS finding. Multivariate pattern analysis showed that, before training, among visual cortical areas, coherent and noisy motion was decoded most accurately in V3A and MT+, respectively. After training, both kinds of motion were decoded most accurately in V3A. Our findings demonstrate that the effects of perceptual learning extend far beyond the retuning of specific neural populations for the trained stimuli. Learning could dramatically modify the inherent functional specializations of visual cortical areas and dynamically reweight their contributions to perceptual decisions based on their representational qualities. These neural changes might serve as the neural substrate for the transfer of perceptual learning.

  11. Visual Speech Perception in Children with Language Learning Impairments

    Science.gov (United States)

    Knowland, Victoria C. P.; Evans, Sam; Snell, Caroline; Rosen, Stuart

    2016-01-01

    Purpose: The purpose of the study was to assess the ability of children with developmental language learning impairments (LLIs) to use visual speech cues from the talking face. Method: In this cross-sectional study, 41 typically developing children (mean age: 8 years 0 months, range: 4 years 5 months to 11 years 10 months) and 27 children with…

  12. Developing Visualization Support System for Teaching/Learning Database Normalization

    Science.gov (United States)

    Folorunso, Olusegun; Akinwale, AdioTaofeek

    2010-01-01

    Purpose: In tertiary institution, some students find it hard to learn database design theory, in particular, database normalization. The purpose of this paper is to develop a visualization tool to give students an interactive hands-on experience in database normalization process. Design/methodology/approach: The model-view-controller architecture…

  13. Multiple Learning Strategies Project. Medical Assistant. Visually Impaired. [Vol. 1.

    Science.gov (United States)

    Varney, Beverly; And Others

    This instructional package, one of two designed for visually impaired students, focuses on the vocational area of medical assistant. Contained in this document are twelve learning modules organized into five units: language; receptioning; asepsis; supplies and equipment maintenance; and diagnostic tests. Each module, printed in block type,…

  14. Multiple Learning Strategies Project. Dietetic Assistant. Visually Impaired. [Vol 1.

    Science.gov (United States)

    Mackinnon, Barbara; And Others

    This instructional package is one of two designed for visually impaired students on the vocational area of dietetic assistant. The forty-seven learning modules are organized into three units: nutrition; menu planning and food ordering; and housekeeping and safety. Each module, printed in large block type, includes these elements: a performance…

  15. Deep Learning Driven Visual Path Prediction from a Single Image.

    Science.gov (United States)

    Huang, Siyu; Li, Xi; Zhang, Zhongfei; He, Zhouzhou; Wu, Fei; Liu, Wei; Tang, Jinhui; Zhuang, Yueting

    2016-09-26

    Capabilities of inference and prediction are significant components of visual systems. Visual path prediction is an important and challenging task among them, with the goal to infer the future path of a visual object in a static scene. This task is complicated as it needs high-level semantic understandings of both the scenes and underlying motion patterns in video sequences. In practice, cluttered situations have also raised higher demands on the effectiveness and robustness of models. Motivated by these observations, we propose a deep learning framework which simultaneously performs deep feature learning for visual representation in conjunction with spatio-temporal context modeling. After that, a unified path planning scheme is proposed to make accurate path prediction based on the analytic results returned by the deep context models. The highly effective visual representation and deep context models ensure that our framework makes a deep semantic understanding of the scenes and motion patterns, consequently improving the performance on visual path prediction task. In experiments, we extensively evaluate the model's performance by constructing two large benchmark datasets from the adaptation of video tracking datasets. The qualitative and quantitative experimental results show that our approach outperforms the state-of-the-art approaches and owns a better generalization capability.

  16. Removing label ambiguity in learning-based visual saliency estimation.

    Science.gov (United States)

    Li, Jia; Xu, Dong; Gao, Wen

    2012-04-01

    Visual saliency is a useful clue to depict visually important image/video contents in many multimedia applications. In visual saliency estimation, a feasible solution is to learn a "feature-saliency" mapping model from the user data obtained by manually labeling activities or eye-tracking devices. However, label ambiguities may also arise due to the inaccurate and inadequate user data. To process the noisy training data, we propose a multi-instance learning to rank approach for visual saliency estimation. In our approach, the correlations between various image patches are incorporated into an ordinal regression framework. By iteratively refining a ranking model and relabeling the image patches with respect to their mutual correlations, the label ambiguities can be effectively removed from the training data. Consequently, visual saliency can be effectively estimated by the ranking model, which can pop out real targets and suppress real distractors. Extensive experiments on two public image data sets show that our approach outperforms 11 state-of-the-art methods remarkably in visual saliency estimation.

  17. Repetitive Transcranial Direct Current Stimulation Induced Excitability Changes of Primary Visual Cortex and Visual Learning Effects-A Pilot Study.

    Science.gov (United States)

    Sczesny-Kaiser, Matthias; Beckhaus, Katharina; Dinse, Hubert R; Schwenkreis, Peter; Tegenthoff, Martin; Höffken, Oliver

    2016-01-01

    Studies on noninvasive motor cortex stimulation and motor learning demonstrated cortical excitability as a marker for a learning effect. Transcranial direct current stimulation (tDCS) is a non-invasive tool to modulate cortical excitability. It is as yet unknown how tDCS-induced excitability changes and perceptual learning in visual cortex correlate. Our study aimed to examine the influence of tDCS on visual perceptual learning in healthy humans. Additionally, we measured excitability in primary visual cortex (V1). We hypothesized that anodal tDCS would improve and cathodal tDCS would have minor or no effects on visual learning. Anodal, cathodal or sham tDCS were applied over V1 in a randomized, double-blinded design over four consecutive days (n = 30). During 20 min of tDCS, subjects had to learn a visual orientation-discrimination task (ODT). Excitability parameters were measured by analyzing paired-stimulation behavior of visual-evoked potentials (ps-VEP) and by measuring phosphene thresholds (PTs) before and after the stimulation period of 4 days. Compared with sham-tDCS, anodal tDCS led to an improvement of visual discrimination learning (p visual perceptual learning and increased cortical excitability. tDCS is a promising tool to alter V1 excitability and, hence, perceptual visual learning.

  18. Online multiple kernel similarity learning for visual search.

    Science.gov (United States)

    Xia, Hao; Hoi, Steven C H; Jin, Rong; Zhao, Peilin

    2014-03-01

    Recent years have witnessed a number of studies on distance metric learning to improve visual similarity search in content-based image retrieval (CBIR). Despite their successes, most existing methods on distance metric learning are limited in two aspects. First, they usually assume the target proximity function follows the family of Mahalanobis distances, which limits their capacity of measuring similarity of complex patterns in real applications. Second, they often cannot effectively handle the similarity measure of multimodal data that may originate from multiple resources. To overcome these limitations, this paper investigates an online kernel similarity learning framework for learning kernel-based proximity functions which goes beyond the conventional linear distance metric learning approaches. Based on the framework, we propose a novel online multiple kernel similarity (OMKS) learning method which learns a flexible nonlinear proximity function with multiple kernels to improve visual similarity search in CBIR. We evaluate the proposed technique for CBIR on a variety of image data sets in which encouraging results show that OMKS outperforms the state-of-the-art techniques significantly.

  19. Two-stage perceptual learning to break visual crowding.

    Science.gov (United States)

    Zhu, Ziyun; Fan, Zhenzhi; Fang, Fang

    2016-01-01

    When a target is presented with nearby flankers in the peripheral visual field, it becomes harder to identify, which is referred to as crowding. Crowding sets a fundamental limit of object recognition in peripheral vision, preventing us from fully appreciating cluttered visual scenes. We trained adult human subjects on a crowded orientation discrimination task and investigated whether crowding could be completely eliminated by training. We discovered a two-stage learning process with this training task. In the early stage, when the target and flankers were separated beyond a certain distance, subjects acquired a relatively general ability to break crowding, as evidenced by the fact that the breaking of crowding could transfer to another crowded orientation, even a crowded motion stimulus, although the transfer to the opposite visual hemi-field was weak. In the late stage, like many classical perceptual learning effects, subjects' performance gradually improved and showed specificity to the trained orientation. We also found that, when the target and flankers were spaced too finely, training could only reduce, rather than completely eliminate, the crowding effect. This two-stage learning process illustrates a learning strategy for our brain to deal with the notoriously difficult problem of identifying peripheral objects in clutter. The brain first learned to solve the "easy and general" part of the problem (i.e., improving the processing resolution and segmenting the target and flankers) and then tackle the "difficult and specific" part (i.e., refining the representation of the target).

  20. Visual Complexity in Orthographic Learning: Modeling Learning across Writing System Variations

    Science.gov (United States)

    Chang, Li-Yun; Plaut, David C.; Perfetti, Charles A.

    2016-01-01

    The visual complexity of orthographies varies across writing systems. Prior research has shown that complexity strongly influences the initial stage of reading development: the perceptual learning of grapheme forms. This study presents a computational simulation that examines the degree to which visual complexity leads to grapheme learning…

  1. Impact of feature saliency on visual category learning.

    Science.gov (United States)

    Hammer, Rubi

    2015-01-01

    People have to sort numerous objects into a large number of meaningful categories while operating in varying contexts. This requires identifying the visual features that best predict the 'essence' of objects (e.g., edibility), rather than categorizing objects based on the most salient features in a given context. To gain this capacity, visual category learning (VCL) relies on multiple cognitive processes. These may include unsupervised statistical learning, that requires observing multiple objects for learning the statistics of their features. Other learning processes enable incorporating different sources of supervisory information, alongside the visual features of the categorized objects, from which the categorical relations between few objects can be deduced. These deductions enable inferring that objects from the same category may differ from one another in some high-saliency feature dimensions, whereas lower-saliency feature dimensions can best differentiate objects from distinct categories. Here I illustrate how feature saliency affects VCL, by also discussing kinds of supervisory information enabling reflective categorization. Arguably, principles debated here are often being ignored in categorization studies.

  2. Pre-School Age Visually Impaired Children's Motives for Learning

    OpenAIRE

    Gudonis, Vytautas

    2015-01-01

    The article presents longitudinal data of the survey of 212 Šiauliai Petras Avižonis Visual Centre’s 6–7-year-old pre-school children’s motives to attend school. A brief theoretical analysis of significance of motives for learning in child’s development is displayed. Analysing research results, a positive experience on development of positive motives for school attendance in pre-school age children attending Šiauliai Petras Avižonis Visual Centre is rendered in a generalising way.

  3. Preexposure to Salty and Sour Taste Enhances Conditioned Taste Aversion to Novel Sucrose

    Science.gov (United States)

    Flores, Veronica L.; Moran, Anan; Bernstein, Max; Katz, Donald B.

    2016-01-01

    Conditioned taste aversion (CTA) is an intensively studied single-trial learning paradigm whereby animals are trained to avoid a taste that has been paired with malaise. Many factors influence the strength of aversion learning; prominently studied among these is taste novelty--the fact that preexposure to the taste conditioned stimulus (CS)…

  4. Shirking, Monitoring, and Risk Aversion

    OpenAIRE

    2014-01-01

    This paper studies the effect of risk aversion on effort under different monitoring schemes. It uses a theoretical model which relaxes the assumption of agents being risk neutral, and investigates changes of effort as monitoring varies. The predictions of the theoretical model are tested using an original experimental setting where the level of risk aversion is measured and monitoring rates vary exogenously. Our results show that shirking decreases with risk aversion, being female, and monito...

  5. Bootstrap Learning and Visual Processing Management on Mobile Robots

    Directory of Open Access Journals (Sweden)

    Mohan Sridharan

    2010-01-01

    Full Text Available A central goal of robotics and AI is to enable a team of robots to operate autonomously in the real world and collaborate with humans over an extended period of time. Though developments in sensor technology have resulted in the deployment of robots in specific applications the ability to accurately sense and interact with the environment is still missing. Key challenges to the widespread deployment of robots include the ability to learn models of environmental features based on sensory inputs, bootstrap off of the learned models to detect and adapt to environmental changes, and autonomously tailor the sensory processing to the task at hand. This paper summarizes a comprehensive effort towards such bootstrap learning, adaptation, and processing management using visual input. We describe probabilistic algorithms that enable a mobile robot to autonomously plan its actions to learn models of color distributions and illuminations. The learned models are used to detect and adapt to illumination changes. Furthermore, we describe a probabilistic sequential decision-making approach that autonomously tailors the visual processing to the task at hand. All algorithms are fully implemented and tested on robot platforms in dynamic environments.

  6. 3D Visualization of Machine Learning Algorithms with Astronomical Data

    Science.gov (United States)

    Kent, Brian R.

    2016-01-01

    We present innovative machine learning (ML) methods using unsupervised clustering with minimum spanning trees (MSTs) to study 3D astronomical catalogs. Utilizing Python code to build trees based on galaxy catalogs, we can render the results with the visualization suite Blender to produce interactive 360 degree panoramic videos. The catalogs and their ML results can be explored in a 3D space using mobile devices, tablets or desktop browsers. We compare the statistics of the MST results to a number of machine learning methods relating to optimization and efficiency.

  7. Signaled two-way avoidance learning using electrical stimulation of the inferior colliculus as negative reinforcement: effects of visual and auditory cues as warning stimuli

    Directory of Open Access Journals (Sweden)

    A.C. Troncoso

    1998-03-01

    Full Text Available The inferior colliculus is a primary relay for the processing of auditory information in the brainstem. The inferior colliculus is also part of the so-called brain aversion system as animals learn to switch off the electrical stimulation of this structure. The purpose of the present study was to determine whether associative learning occurs between aversion induced by electrical stimulation of the inferior colliculus and visual and auditory warning stimuli. Rats implanted with electrodes into the central nucleus of the inferior colliculus were placed inside an open-field and thresholds for the escape response to electrical stimulation of the inferior colliculus were determined. The rats were then placed inside a shuttle-box and submitted to a two-way avoidance paradigm. Electrical stimulation of the inferior colliculus at the escape threshold (98.12 ± 6.15 (A, peak-to-peak was used as negative reinforcement and light or tone as the warning stimulus. Each session consisted of 50 trials and was divided into two segments of 25 trials in order to determine the learning rate of the animals during the sessions. The rats learned to avoid the inferior colliculus stimulation when light was used as the warning stimulus (13.25 ± 0.60 s and 8.63 ± 0.93 s for latencies and 12.5 ± 2.04 and 19.62 ± 1.65 for frequencies in the first and second halves of the sessions, respectively, P0.05 in both cases. Taken together, the present results suggest that rats learn to avoid the inferior colliculus stimulation when light is used as the warning stimulus. However, this learning process does not occur when the neutral stimulus used is an acoustic one. Electrical stimulation of the inferior colliculus may disturb the signal transmission of the stimulus to be conditioned from the inferior colliculus to higher brain structures such as amygdala

  8. Influence of visual observational conditions on tongue motor learning

    DEFF Research Database (Denmark)

    Kothari, Mohit; Liu, Xuimei; Baad-Hansen, Lene;

    2016-01-01

    To investigate the impact of visual observational conditions on performance during a standardized tongue-protrusion training (TPT) task and to evaluate subject-based reports of helpfulness, disturbance, pain, and fatigue due to the observational conditions on 0-10 numerical rating scales. Forty...... regarding the level of disturbance, pain or fatigue. Self-observation of tongue-training facilitated behavioral aspects of tongue motor learning compared with model-observation but not compared with control....

  9. Perceptual learning reconfigures the effects of visual adaptation.

    Science.gov (United States)

    McGovern, David P; Roach, Neil W; Webb, Ben S

    2012-09-26

    Our sensory experiences over a range of different timescales shape our perception of the environment. Two particularly striking short-term forms of plasticity with manifestly different time courses and perceptual consequences are those caused by visual adaptation and perceptual learning. Although conventionally treated as distinct forms of experience-dependent plasticity, their neural mechanisms and perceptual consequences have become increasingly blurred, raising the possibility that they might interact. To optimize our chances of finding a functionally meaningful interaction between learning and adaptation, we examined in humans the perceptual consequences of learning a fine discrimination task while adapting the neurons that carry most information for performing this task. Learning improved discriminative accuracy to a level that ultimately surpassed that in an unadapted state. This remarkable improvement came at a price: adapting directions that before learning had little effect elevated discrimination thresholds afterward. The improvements in discriminative accuracy grew quickly and surpassed unadapted levels within the first few training sessions, whereas the deterioration in discriminative accuracy had a different time course. This learned reconfiguration of adapted discriminative accuracy occurred without a concomitant change to the characteristic perceptual biases induced by adaptation, suggesting that the system was still in an adapted state. Our results point to a functionally meaningful push-pull interaction between learning and adaptation in which a gain in sensitivity in one adapted state is balanced by a loss of sensitivity in other adapted states.

  10. Learning Visual Representations for Perception-Action Systems

    DEFF Research Database (Denmark)

    Piater, Justus; Jodogne, Sebastien; Detry, Renaud;

    2011-01-01

    We discuss vision as a sensory modality for systems that effect actions in response to perceptions. While the internal representations informed by vision may be arbitrarily complex, we argue that in many cases it is advantageous to link them rather directly to action via learned mappings. These a......We discuss vision as a sensory modality for systems that effect actions in response to perceptions. While the internal representations informed by vision may be arbitrarily complex, we argue that in many cases it is advantageous to link them rather directly to action via learned mappings....... These arguments are illustrated by two examples of our own work. First, our RLVC algorithm performs reinforcement learning directly on the visual input space. To make this very large space manageable, RLVC interleaves the reinforcement learner with a supervised classification algorithm that seeks to split...... perceptual states so as to reduce perceptual aliasing. This results in an adaptive discretization of the perceptual space based on the presence or absence of visual features. Its extension RLJC also handles continuous action spaces. In contrast to the minimalistic visual representations produced by RLVC...

  11. Feature saliency and feedback information interactively impact visual category learning.

    Science.gov (United States)

    Hammer, Rubi; Sloutsky, Vladimir; Grill-Spector, Kalanit

    2015-01-01

    Visual category learning (VCL) involves detecting which features are most relevant for categorization. VCL relies on attentional learning, which enables effectively redirecting attention to object's features most relevant for categorization, while 'filtering out' irrelevant features. When features relevant for categorization are not salient, VCL relies also on perceptual learning, which enables becoming more sensitive to subtle yet important differences between objects. Little is known about how attentional learning and perceptual learning interact when VCL relies on both processes at the same time. Here we tested this interaction. Participants performed VCL tasks in which they learned to categorize novel stimuli by detecting the feature dimension relevant for categorization. Tasks varied both in feature saliency (low-saliency tasks that required perceptual learning vs. high-saliency tasks), and in feedback information (tasks with mid-information, moderately ambiguous feedback that increased attentional load, vs. tasks with high-information non-ambiguous feedback). We found that mid-information and high-information feedback were similarly effective for VCL in high-saliency tasks. This suggests that an increased attentional load, associated with the processing of moderately ambiguous feedback, has little effect on VCL when features are salient. In low-saliency tasks, VCL relied on slower perceptual learning; but when the feedback was highly informative participants were able to ultimately attain the same performance as during the high-saliency VCL tasks. However, VCL was significantly compromised in the low-saliency mid-information feedback task. We suggest that such low-saliency mid-information learning scenarios are characterized by a 'cognitive loop paradox' where two interdependent learning processes have to take place simultaneously.

  12. Analysis and Visualization of Relations in eLearning

    Science.gov (United States)

    Dráždilová, Pavla; Obadi, Gamila; Slaninová, Kateřina; Martinovič, Jan; Snášel, Václav

    The popularity of eLearning systems is growing rapidly; this growth is enabled by the consecutive development in Internet and multimedia technologies. Web-based education became wide spread in the past few years. Various types of learning management systems facilitate development of Web-based courses. Users of these courses form social networks through the different activities performed by them. This chapter focuses on searching the latent social networks in eLearning systems data. These data consist of students activity records wherein latent ties among actors are embedded. The social network studied in this chapter is represented by groups of students who have similar contacts and interact in similar social circles. Different methods of data clustering analysis can be applied to these groups, and the findings show the existence of latent ties among the group members. The second part of this chapter focuses on social network visualization. Graphical representation of social network can describe its structure very efficiently. It can enable social network analysts to determine the network degree of connectivity. Analysts can easily determine individuals with a small or large amount of relationships as well as the amount of independent groups in a given network. When applied to the field of eLearning, data visualization simplifies the process of monitoring the study activities of individuals or groups, as well as the planning of educational curriculum, the evaluation of study processes, etc.

  13. Learning indoor robot navigation using visual and sensorimotor map information.

    Science.gov (United States)

    Yan, Wenjie; Weber, Cornelius; Wermter, Stefan

    2013-01-01

    As a fundamental research topic, autonomous indoor robot navigation continues to be a challenge in unconstrained real-world indoor environments. Although many models for map-building and planning exist, it is difficult to integrate them due to the high amount of noise, dynamics, and complexity. Addressing this challenge, this paper describes a neural model for environment mapping and robot navigation based on learning spatial knowledge. Considering that a person typically moves within a room without colliding with objects, this model learns the spatial knowledge by observing the person's movement using a ceiling-mounted camera. A robot can plan and navigate to any given position in the room based on the acquired map, and adapt it based on having identified possible obstacles. In addition, salient visual features are learned and stored in the map during navigation. This anchoring of visual features in the map enables the robot to find and navigate to a target object by showing an image of it. We implement this model on a humanoid robot and tests are conducted in a home-like environment. Results of our experiments show that the learned sensorimotor map masters complex navigation tasks.

  14. Visual and Experiential Learning Opportunities through Geospatial Data

    Science.gov (United States)

    Gardiner, N.; Bulletins, S.

    2007-12-01

    Global observation data from satellites are essential for both research and education about Earth's climate because they help convey the temporal and spatial scales inherent to the subject, which are beyond most people's experience. Experts in the development of visualizations using spatial data distinguish the process of learning through data exploration from the process of learning by absorbing a story told from beginning to end. The former requires the viewer to absorb complex spatial and temporal dynamics inherent to visualized data and therefore is a process best undertaken by those familiar with the data and processes represented. The latter requires that the viewer understand the intended presentation of concepts, so story telling can be employed to educate viewers with varying backgrounds and familiarity with a given subject. Three examples of climate science education, drawn from the current science program Science Bulletins (American Museum of Natural History, New York, USA), demonstrate the power of visualized global earth observations for climate science education. The first example seeks to explain the potential for sea level rise on a global basis. A short feature film includes the visualized, projected effects of sea level rise at local to global scales; this visualization complements laboratory and field observations of glacier retreat and paleoclimatic reconstructions based on fossilized coral reef analysis, each of which is also depicted in the film. The narrative structure keeps learners focused on discrete scientific concepts. The second example utilizes half-hourly cloud observations to demonstrate weather and climate patterns to audiences on a global basis. Here, the scientific messages are qualitatively simpler, but the viewer must deduce his own complex visual understanding of the visualized data. Finally, we present plans for distributing climate science education products via mediated public events whereby participants learn from climate

  15. Effects of subdiaphragmatic vagotomy on the acquisition of a radiation-induced conditioned taste aversion

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, W.A.; Rabin, B.M.; Lee, J.

    1987-01-01

    The effect of subdiaphragmatic vagotomy on the acquisition of a radiation-induced taste aversion was examined to assess the importance of the vagus nerve in transmitting information on the peripheral toxicity of radiation to the brain. Vagotomy had no effect on taste aversion learning, consistent with reports using other toxins. The data support the involvement of a blood-borne factor in the acquisition of taste aversion induced by ionizing radiation.

  16. Integration of Neurobiological and Computational Analyses of the Neural Network Essentials for Conditioned Taste Aversion

    Science.gov (United States)

    1991-04-29

    insular cortex lesions on the conditioned taste aversion, passive avoidance, and neophobia in the rat using the excitotoxin ibotenic acid. Behavioral...Psychology .1, 5-6, 1973. Fitzgerald, R. E. and Burton, M. J. Neophobia and conditioned taste aversion deficits in the rat produced by undercutting temporal...1967. Nachman, M. and Ashe, J. H. Effects of basolateral amygdala lesions on neophobia , learned taste aversions, and sodium appetite in rats. Journal of

  17. The strength of aversive and appetitive associations and maladaptive behaviors.

    Science.gov (United States)

    Itzhak, Yossef; Perez-Lanza, Daniel; Liddie, Shervin

    2014-08-01

    Certain maladaptive behaviors are thought to be acquired through classical Pavlovian conditioning. Exaggerated fear response, which can develop through Pavlovian conditioning, is associated with acquired anxiety disorders such as post-traumatic stress disorders (PTSDs). Inflated reward-seeking behavior, which develops through Pavlovian conditioning, underlies some types of addictive behavior (e.g., addiction to drugs, food, and gambling). These maladaptive behaviors are dependent on associative learning and the development of long-term memory (LTM). In animal models, an aversive reinforcer (fear conditioning) encodes an aversive contextual and cued LTM. On the other hand, an appetitive reinforcer results in conditioned place preference (CPP) that encodes an appetitive contextual LTM. The literature on weak and strong associative learning pertaining to the development of aversive and appetitive LTM is relatively scarce; thus, this review is particularly focused on the strength of associative learning. The strength of associative learning is dependent on the valence of the reinforcer and the salience of the conditioned stimulus that ultimately sways the strength of the memory trace. Our studies suggest that labile (weak) aversive and appetitive LTM may share similar signaling pathways, whereas stable (strong) aversive and appetitive LTM is mediated through different pathways. In addition, we provide some evidence suggesting that extinction of aversive fear memory and appetitive drug memory is likely to be mediated through different signaling molecules. We put forward the importance of studies aimed to investigate the molecular mechanisms underlying the development of weak and strong memories (aversive and appetitive), which would ultimately help in the development of targeted pharmacotherapies for the management of maladaptive behaviors that arise from classical Pavlovian conditioning.

  18. Visual Tracking Based on Extreme Learning Machine and Sparse Representation

    Directory of Open Access Journals (Sweden)

    Baoxian Wang

    2015-10-01

    Full Text Available The existing sparse representation-based visual trackers mostly suffer from both being time consuming and having poor robustness problems. To address these issues, a novel tracking method is presented via combining sparse representation and an emerging learning technique, namely extreme learning machine (ELM. Specifically, visual tracking can be divided into two consecutive processes. Firstly, ELM is utilized to find the optimal separate hyperplane between the target observations and background ones. Thus, the trained ELM classification function is able to remove most of the candidate samples related to background contents efficiently, thereby reducing the total computational cost of the following sparse representation. Secondly, to further combine ELM and sparse representation, the resultant confidence values (i.e., probabilities to be a target of samples on the ELM classification function are used to construct a new manifold learning constraint term of the sparse representation framework, which tends to achieve robuster results. Moreover, the accelerated proximal gradient method is used for deriving the optimal solution (in matrix form of the constrained sparse tracking model. Additionally, the matrix form solution allows the candidate samples to be calculated in parallel, thereby leading to a higher efficiency. Experiments demonstrate the effectiveness of the proposed tracker.

  19. Visual tracking based on extreme learning machine and sparse representation.

    Science.gov (United States)

    Wang, Baoxian; Tang, Linbo; Yang, Jinglin; Zhao, Baojun; Wang, Shuigen

    2015-10-22

    The existing sparse representation-based visual trackers mostly suffer from both being time consuming and having poor robustness problems. To address these issues, a novel tracking method is presented via combining sparse representation and an emerging learning technique, namely extreme learning machine (ELM). Specifically, visual tracking can be divided into two consecutive processes. Firstly, ELM is utilized to find the optimal separate hyperplane between the target observations and background ones. Thus, the trained ELM classification function is able to remove most of the candidate samples related to background contents efficiently, thereby reducing the total computational cost of the following sparse representation. Secondly, to further combine ELM and sparse representation, the resultant confidence values (i.e., probabilities to be a target) of samples on the ELM classification function are used to construct a new manifold learning constraint term of the sparse representation framework, which tends to achieve robuster results. Moreover, the accelerated proximal gradient method is used for deriving the optimal solution (in matrix form) of the constrained sparse tracking model. Additionally, the matrix form solution allows the candidate samples to be calculated in parallel, thereby leading to a higher efficiency. Experiments demonstrate the effectiveness of the proposed tracker.

  20. Neurofeedback in Learning Disabled Children: Visual versus Auditory Reinforcement.

    Science.gov (United States)

    Fernández, Thalía; Bosch-Bayard, Jorge; Harmony, Thalía; Caballero, María I; Díaz-Comas, Lourdes; Galán, Lídice; Ricardo-Garcell, Josefina; Aubert, Eduardo; Otero-Ojeda, Gloria

    2016-03-01

    Children with learning disabilities (LD) frequently have an EEG characterized by an excess of theta and a deficit of alpha activities. NFB using an auditory stimulus as reinforcer has proven to be a useful tool to treat LD children by positively reinforcing decreases of the theta/alpha ratio. The aim of the present study was to optimize the NFB procedure by comparing the efficacy of visual (with eyes open) versus auditory (with eyes closed) reinforcers. Twenty LD children with an abnormally high theta/alpha ratio were randomly assigned to the Auditory or the Visual group, where a 500 Hz tone or a visual stimulus (a white square), respectively, was used as a positive reinforcer when the value of the theta/alpha ratio was reduced. Both groups had signs consistent with EEG maturation, but only the Auditory Group showed behavioral/cognitive improvements. In conclusion, the auditory reinforcer was more efficacious in reducing the theta/alpha ratio, and it improved the cognitive abilities more than the visual reinforcer.

  1. Visual Literacy and Biochemistry Learning: The role of external representations

    Directory of Open Access Journals (Sweden)

    V.J.S.V. Santos

    2011-04-01

    Full Text Available Visual Literacy can bedefined as people’s ability to understand, use, think, learn and express themselves through external representations (ER in a given subject. This research aims to investigate the development of abilities of ERs reading and interpretation by students from a Biochemistry graduate course of theFederal University of São João Del-Rei. In this way, Visual Literacy level was  assessed using a questionnaire validatedin a previous educational research. This diagnosis questionnaire was elaborated according to six visual abilitiesidentified as essential for the study of the metabolic pathways. The initial statistical analysis of data collectedin this study was carried out using ANOVA method. Results obtained showed that the questionnaire used is adequate for the research and indicated that the level of Visual Literacy related to the metabolic processes increased significantly with the progress of the students in the graduation course. There was also an indication of a possible interference in the student’s performancedetermined by the cutoff punctuation in the university selection process.

  2. Local matrix learning in clustering and applications for manifold visualization.

    Science.gov (United States)

    Arnonkijpanich, Banchar; Hasenfuss, Alexander; Hammer, Barbara

    2010-05-01

    Electronic data sets are increasing rapidly with respect to both, size of the data sets and data resolution, i.e. dimensionality, such that adequate data inspection and data visualization have become central issues of data mining. In this article, we present an extension of classical clustering schemes by local matrix adaptation, which allows a better representation of data by means of clusters with an arbitrary spherical shape. Unlike previous proposals, the method is derived from a global cost function. The focus of this article is to demonstrate the applicability of this matrix clustering scheme to low-dimensional data embedding for data inspection. The proposed method is based on matrix learning for neural gas and manifold charting. This provides an explicit mapping of a given high-dimensional data space to low dimensionality. We demonstrate the usefulness of this method for data inspection and manifold visualization.

  3. Learning Analytics: A Case Study of the Process of Design of Visualizations

    Science.gov (United States)

    Olmos, Martin; Corrin, Linda

    2012-01-01

    The ability to visualize student engagement and experience data provides valuable opportunities for learning support and curriculum design. With the rise of the use of learning analytics to provide "actionable intelligence" on students' learning, the challenge is to create visualizations of the data, which are clear and useful to the…

  4. Appetitive-aversive interactions in Pavlovian fear conditioning.

    Science.gov (United States)

    Nasser, Helen M; McNally, Gavan P

    2012-06-01

    The existence of value coding and salience coding neurons in the mammalian brain, including in habenula and ventral tegmental area, has sparked considerable interest in the interactions that occur between Pavlovian appetitive and aversive conditioning. Here we studied these appetitive-aversive interactions at the behavioral level by assessing the learning that occurs when a Pavlovian appetitive conditioned stimulus (conditional stimulus, CS) serves as a CS for shock in Pavlovian fear conditioning. A Pavlovian appetitive CS was retarded in the rate at which it could be transformed into a fear CS (counterconditioning), but the presence of the appetitive CS augmented fear learning to a concurrently presented neutral CS (superconditioning). Retardation of fear learning was not alleviated by manipulations designed to restore the associability of the appetitive CS before fear conditioning but was alleviated by manipulations designed to increase the aversive quality of the shock unconditioned stimulus (US). These findings are consistent with opponent interactions between the appetitive and aversive motivational systems and provide a behavioral approach for assessing the neural correlates of these appetitive-aversive interactions.

  5. Investigation of anabolic steroids in two taste aversion paradigms.

    Science.gov (United States)

    Ganesan, R; Rosellini, R A; Svare, B

    1993-02-01

    The aversive effects of estradiol have been studied in two different taste aversion paradigms. A similar investigation was undertaken for the anabolic-androgenic steroids, nandralone and testosterone cypionate, using Rockland-Swiss mice. Experiments 1 and 2 used the brief exposure of a novel saccharin solution as the conditioned stimulus for taste aversion learning, and showed that anabolic steroids (1 mg) do not induce taste aversions. Instead, these hormones induced a small non-contingent increase in saccharin preference. Experiment 3 showed that daily nandralone administration (1 mg/day) had a greater anabolic effect than the same dose of testosterone cypionate. Experiment 4 paired the continuous exposure to a novel diet with daily nandralone injections, and showed that steroid treatment increased intake of the novel diet. When the novel diet was subsequently presented with the familiar diet in a two-choice preference test, there was no indication that an aversion was conditioned to the novel target diet. On the contrary, nandralone treatment significantly increased the preference for the novel diet. These experiments show that anabolic-androgenic steroids do not have aversive effects in mice, and that they may have positive consequences.

  6. Summarize to learn: summarization and visualization of text for ubiquitous learning

    DEFF Research Database (Denmark)

    Chongtay, Rocio; Last, Mark; Verbeke, Mathias;

    2013-01-01

    Visualizations can stand in many relations to texts – and, as research into learning with pictures has shown, they can become particularly valuable when they transform the contents of the text (rather than just duplicate its message or structure it). But what kinds of transformations can be parti...

  7. Using E-Learning Portfolio Technology To Support Visual Art Learning

    Directory of Open Access Journals (Sweden)

    Greer Jones-Woodham

    2009-08-01

    Full Text Available Inspired by self-directed learning (SDL theories, this paper uses learning portfolios as a reflective practice to improve student learning and develop personal responsibility, growth and autonomy in learning in a Visual Arts course. Students use PowerPoint presentations to demonstrate their concepts by creating folders that are linked to e-portfolios on the University website. This paper establishes the role of learning e-portfolios to improve teaching and learning as a model of reflection, collaboration and documentation in the making of art as a self-directed process. These portfolios link students' creative thinking to their conceptual frameworks. They also establish a process of inquiry using journals to map students' processes through their reflections and peer feedback. This practice argues that learning e-portfolios in studio art not only depends on a set of objectives whose means are justified by an agreed end but also depends on a practice that engages students' reflection about their actions while in their art- making practice. Using the principles of the maker as the intuitive and reflective practitioner, the making as the process in which the learning e-portfolios communicate the process and conceptual frameworks of learning and the eventual product, and the made as evidence of that learning in light of progress made, this paper demonstrates that learning-in-action and reflecting-in and-on-action are driven by self-direction. With technology, students bring their learning context to bear with the use of SDL. Students' use of PowerPoint program technology in making their portfolios is systematic and builds on students' competencies as this process guides students' beliefs and actions about their work that is based on theory and concepts in response to a visual culture that is Trinidad and Tobago. Students' self–directed art-making process as a self directed learning, models the process of articulated learning. Communicating about

  8. Conditioned taste aversion, drugs of abuse and palatability

    Science.gov (United States)

    Lin, Jian-You; Arthurs, Joe; Reilly, Steve

    2014-01-01

    LIN, J.-Y., J. Arthurs and S. Reilly. Conditioned taste aversion: Palatability and drugs of abuse. NEUROSCI BIOBEHAV REV XX(x) XXX-XXX, 2014. – We consider conditioned taste aversion to involve a learned reduction in the palatability of a taste (and hence in amount consumed) based on the association that develops when a taste experience is followed by gastrointestinal malaise. The present article evaluates the well-established finding that drugs of abuse, at doses that are otherwise considered rewarding and self-administered, cause intake suppression. Our recent work using lick pattern analysis shows that drugs of abuse also cause a palatability downshift and, therefore, support conditioned taste aversion learning. PMID:24813806

  9. Robust Visual Tracking via Sparsity-Induced Subspace Learning.

    Science.gov (United States)

    Sui, Yao; Zhang, Shunli; Zhang, Li

    2015-12-01

    Target representation is a necessary component for a robust tracker. However, during tracking, many complicated factors may make the accumulated errors in the representation significantly large, leading to tracking drift. This paper aims to improve the robustness of target representation to avoid the influence of the accumulated errors, such that the tracker only acquires the information that facilitates tracking and ignores the distractions. We observe that the locally mutual relations between the feature observations of temporally obtained targets are beneficial to the subspace representation in visual tracking. Thus, we propose a novel subspace learning algorithm for visual tracking, which imposes joint row-wise sparsity structure on the target subspace to adaptively exclude distractive information. The sparsity is induced by exploiting the locally mutual relations between the feature observations during learning. To this end, we formulate tracking as a subspace sparsity inducing problem. A large number of experiments on various challenging video sequences demonstrate that our tracker outperforms many other state-of-the-art trackers.

  10. Fluoxetine does not enhance visual perceptual learning and triazolam specifically impairs learning transfer

    Directory of Open Access Journals (Sweden)

    Alice Kitty Lagas

    2016-10-01

    Full Text Available The selective serotonin reuptake inhibitor fluoxetine significantly enhances adult visual cortex plasticity within the rat. This effect is related to decreased gamma-aminobutyric acid (GABA mediated inhibition and identifies fluoxetine as a potential agent for enhancing plasticity in the adult human brain. We tested the hypothesis that fluoxetine would enhance visual perceptual learning of a motion direction discrimination (MDD task in humans. We also investigated 1 the effect of fluoxetine on visual and motor cortex excitability and 2 the impact of increased GABA mediated inhibition following a single dose of triazolam on post-training MDD task performance. Within a double blind, placebo controlled design, 20 healthy adult participants completed a 19-day course of fluoxetine (n = 10, 20mg per day or placebo (n = 10. Participants were trained on the MDD task over the final five days of fluoxetine administration. Accuracy for the trained MDD stimulus and an untrained MDD stimulus configuration was assessed before and after training, after triazolam and one week after triazolam. Motor and visual cortex excitability was measured using transcranial magnetic stimulation. Fluoxetine did not enhance the magnitude or rate of perceptual learning and full transfer of learning to the untrained stimulus was observed for both groups. After training was complete, trazolam had no effect on trained task performance but significantly impaired untrained task performance. No consistent effects of fluoxetine on cortical excitability were observed. The results do not support the hypothesis that fluoxetine can enhance learning in humans. However, the specific effect of triazolam on MDD task performance for the untrained stimulus suggests that learning and learning transfer relay on dissociable neural mechanisms.

  11. Fluoxetine Does Not Enhance Visual Perceptual Learning and Triazolam Specifically Impairs Learning Transfer

    Science.gov (United States)

    Lagas, Alice K.; Black, Joanna M.; Byblow, Winston D.; Fleming, Melanie K.; Goodman, Lucy K.; Kydd, Robert R.; Russell, Bruce R.; Stinear, Cathy M.; Thompson, Benjamin

    2016-01-01

    The selective serotonin reuptake inhibitor fluoxetine significantly enhances adult visual cortex plasticity within the rat. This effect is related to decreased gamma-aminobutyric acid (GABA) mediated inhibition and identifies fluoxetine as a potential agent for enhancing plasticity in the adult human brain. We tested the hypothesis that fluoxetine would enhance visual perceptual learning of a motion direction discrimination (MDD) task in humans. We also investigated (1) the effect of fluoxetine on visual and motor cortex excitability and (2) the impact of increased GABA mediated inhibition following a single dose of triazolam on post-training MDD task performance. Within a double blind, placebo controlled design, 20 healthy adult participants completed a 19-day course of fluoxetine (n = 10, 20 mg per day) or placebo (n = 10). Participants were trained on the MDD task over the final 5 days of fluoxetine administration. Accuracy for the trained MDD stimulus and an untrained MDD stimulus configuration was assessed before and after training, after triazolam and 1 week after triazolam. Motor and visual cortex excitability were measured using transcranial magnetic stimulation. Fluoxetine did not enhance the magnitude or rate of perceptual learning and full transfer of learning to the untrained stimulus was observed for both groups. After training was complete, trazolam had no effect on trained task performance but significantly impaired untrained task performance. No consistent effects of fluoxetine on cortical excitability were observed. The results do not support the hypothesis that fluoxetine can enhance learning in humans. However, the specific effect of triazolam on MDD task performance for the untrained stimulus suggests that learning and learning transfer rely on dissociable neural mechanisms. PMID:27807412

  12. The influence of attention, learning, and motivation on visual search.

    Science.gov (United States)

    Dodd, Michael D; Flowers, John H

    2012-01-01

    The 59th Annual Nebraska Symposium on Motivation (The Influence of Attention, Learning, and Motivation on Visual Search) took place April 7-8, 2011, on the University of Nebraska-Lincoln campus. The symposium brought together leading scholars who conduct research related to visual search at a variety levels for a series of talks, poster presentations, panel discussions, and numerous additional opportunities for intellectual exchange. The Symposium was also streamed online for the first time in the history of the event, allowing individuals from around the world to view the presentations and submit questions. The present volume is intended to both commemorate the event itself and to allow our speakers additional opportunity to address issues and current research that have since arisen. Each of the speakers (and, in some cases, their graduate students and post docs) has provided a chapter which both summarizes and expands on their original presentations. In this chapter, we sought to a) provide additional context as to how the Symposium came to be, b) discuss why we thought that this was an ideal time to organize a visual search symposium, and c) to briefly address recent trends and potential future directions in the field. We hope you find the volume both enjoyable and informative, and we thank the authors who have contributed a series of engaging chapters.

  13. Alcohol reduces aversion to ambiguity

    Science.gov (United States)

    Tyszka, Tadeusz; Macko, Anna; Stańczak, Maciej

    2015-01-01

    Several years ago, Cohen et al. (1958) demonstrated that under the influence of alcohol drivers became more risk prone, although their risk perception remained unchanged. Research shows that ambiguity aversion is to some extent positively correlated with risk aversion, though not very highly (Camerer and Weber, 1992). The question addressed by the present research is whether alcohol reduces ambiguity aversion. Our research was conducted in a natural setting (a restaurant bar), where customers with differing levels of alcohol intoxication were offered a choice between a risky and an ambiguous lottery. We found that alcohol reduced ambiguity aversion and that the effect occurred in men but not women. We interpret these findings in terms of the risk-as-value hypothesis, according to which, people in Western culture tend to value risk, and suggest that alcohol consumption triggers adherence to socially and culturally valued patterns of conduct different for men and women. PMID:25642202

  14. Alcohol reduces aversion to ambiguity

    Directory of Open Access Journals (Sweden)

    Tadeusz eTyszka

    2015-01-01

    Full Text Available Several years ago, Cohen, Dearnaley, and Hansel [1] demonstrated that under the influence of alcohol drivers became more risk prone, although their risk perception remained unchanged. Research shows that ambiguity aversion is to some extent positively correlated with risk aversion, though not very highly [2]. The question addressed by the present research is whether alcohol reduces ambiguity aversion. Our research was conducted in a natural setting (a restaurant bar, where customers with differing levels of alcohol intoxication were offered a choice between a risky and an ambiguous lottery. We found that alcohol reduced ambiguity aversion and that the effect occurred in men but not women. We interpret these findings in terms of the risk-as-value hypothesis, according to which, people in Western culture tend to value risk, and suggest that alcohol consumption triggers adherence to socially and culturally valued patterns of conduct different for men and women.

  15. Can Teachers Learn to Cope with Our Visual Society?

    Science.gov (United States)

    Oxford, Jacqulinn; Moore, David M.

    1979-01-01

    Outlines a concentrated in-service visual training program which incorporates (1) perceptual effects of visual stimuli, (2) synthetic and natural stimuli, (3) non-verbal stimuli, (4) pictorial communication, (5) visual persuasion, and (6) creative visualization. (Author/CMV)

  16. Differential Effects of Music and Video Gaming During Breaks on Auditory and Visual Learning.

    Science.gov (United States)

    Liu, Shuyan; Kuschpel, Maxim S; Schad, Daniel J; Heinz, Andreas; Rapp, Michael A

    2015-11-01

    The interruption of learning processes by breaks filled with diverse activities is common in everyday life. This study investigated the effects of active computer gaming and passive relaxation (rest and music) breaks on auditory versus visual memory performance. Young adults were exposed to breaks involving (a) open eyes resting, (b) listening to music, and (c) playing a video game, immediately after memorizing auditory versus visual stimuli. To assess learning performance, words were recalled directly after the break (an 8:30 minute delay) and were recalled and recognized again after 7 days. Based on linear mixed-effects modeling, it was found that playing the Angry Birds video game during a short learning break impaired long-term retrieval in auditory learning but enhanced long-term retrieval in visual learning compared with the music and rest conditions. These differential effects of video games on visual versus auditory learning suggest specific interference of common break activities on learning.

  17. Summarize to learn: summarization and visualization of text for ubiquitous learning

    DEFF Research Database (Denmark)

    Chongtay, Rocio; Last, Mark; Verbeke, Mathias;

    2013-01-01

    Visualizations can stand in many relations to texts – and, as research into learning with pictures has shown, they can become particularly valuable when they transform the contents of the text (rather than just duplicate its message or structure it). But what kinds of transformations can...... be particularly helpful in the learning process? In this paper, we argue that interacting with, and creating, summaries of texts is a key transformation technique, and we investigate how textual and graphical summarization approaches, as well as automatic and manual summarization, can complement one another...

  18. Fixed-Rank Representation for Unsupervised Visual Learning

    CERN Document Server

    Liu, Risheng; De la Torre, Fernando; Su, Zhixun

    2012-01-01

    Subspace clustering and feature extraction are two of the most extensive unsupervised visual learning tasks in computer vision and pattern recognition. In this paper, we pose these two problems in a unified framework, named fixed-rank representation (FRR). For subspace clustering, our first contribution is to show that, when the data is clean, we can efficiently solve FRR in closed-form and the global optimal solution to FRR can exactly recover the multiple subspace structure. Furthermore, we prove that under some suitable conditions, even with insufficient observations, the memberships of data points still can be exactly recovered by FRR. In the case that the data is corrupted by noises and outliers, a sparse regularization is introduced to achieve robustness for FRR. For feature extraction, we provide some new insights to understand existing methods, which lead to a new approach for robust feature extraction. As a non-trivial byproduct, a fast numerical solver is developed for FRR. Experimental results on b...

  19. Visually Impaired People with Learning Difficulties: Their Education from 1900 to 1970--Policy, Practice and Experience

    Science.gov (United States)

    French, Sally

    2008-01-01

    By means of documentary evidence and six in-depth interviews, this paper traces policy and practice relating to the education of visually impaired children with learning difficulties from 1900 to 1970. It reveals that if visually impaired children with learning difficulties were given an education at all, their needs were not usually met and they…

  20. Supporting Multimedia Learning with Visual Signalling and Animated Pedagogical Agent: Moderating Effects of Prior Knowledge

    Science.gov (United States)

    Johnson, A. M.; Ozogul, G.; Reisslein, M.

    2015-01-01

    An experiment examined the effects of visual signalling to relevant information in multiple external representations and the visual presence of an animated pedagogical agent (APA). Students learned electric circuit analysis using a computer-based learning environment that included Cartesian graphs, equations and electric circuit diagrams. The…

  1. Changes of the Prefrontal EEG (Electroencephalogram) Activities According to the Repetition of Audio-Visual Learning.

    Science.gov (United States)

    Kim, Yong-Jin; Chang, Nam-Kee

    2001-01-01

    Investigates the changes of neuronal response according to a four time repetition of audio-visual learning. Obtains EEG data from the prefrontal (Fp1, Fp2) lobe from 20 subjects at the 8th grade level. Concludes that the habituation of neuronal response shows up in repetitive audio-visual learning and brain hemisphericity can be changed by…

  2. How Spatial Abilities and Dynamic Visualizations Interplay When Learning Functional Anatomy with 3D Anatomical Models

    Science.gov (United States)

    Berney, Sandra; Bétrancourt, Mireille; Molinari, Gaëlle; Hoyek, Nady

    2015-01-01

    The emergence of dynamic visualizations of three-dimensional (3D) models in anatomy curricula may be an adequate solution for spatial difficulties encountered with traditional static learning, as they provide direct visualization of change throughout the viewpoints. However, little research has explored the interplay between learning material…

  3. A Visual Haptic System for Children with Learning Disabilities: Software and Hardware Design Considerations

    Science.gov (United States)

    Subrahmaniyan, Neeraja; Krishnaswamy, Swetha; Chowriappa, Ashirwad; Srimathveeravalli, Govindarajan; Bisantz, Ann; Shriber, Linda; Kesavadas, Thenkurussi

    2012-01-01

    Research has shown that children with learning disabilities exhibit considerable challenges with visual motor integration. While there are specialized Occupational Therapy interventions aimed at visual motor integration, computer games and virtual toys have now become increasingly popular, forming an integral part of children's learning and play.…

  4. Neural Network Machine Learning and Dimension Reduction for Data Visualization

    Science.gov (United States)

    Liles, Charles A.

    2014-01-01

    Neural network machine learning in computer science is a continuously developing field of study. Although neural network models have been developed which can accurately predict a numeric value or nominal classification, a general purpose method for constructing neural network architecture has yet to be developed. Computer scientists are often forced to rely on a trial-and-error process of developing and improving accurate neural network models. In many cases, models are constructed from a large number of input parameters. Understanding which input parameters have the greatest impact on the prediction of the model is often difficult to surmise, especially when the number of input variables is very high. This challenge is often labeled the "curse of dimensionality" in scientific fields. However, techniques exist for reducing the dimensionality of problems to just two dimensions. Once a problem's dimensions have been mapped to two dimensions, it can be easily plotted and understood by humans. The ability to visualize a multi-dimensional dataset can provide a means of identifying which input variables have the highest effect on determining a nominal or numeric output. Identifying these variables can provide a better means of training neural network models; models can be more easily and quickly trained using only input variables which appear to affect the outcome variable. The purpose of this project is to explore varying means of training neural networks and to utilize dimensional reduction for visualizing and understanding complex datasets.

  5. Application of visual cryptography for learning in optics and photonics

    Science.gov (United States)

    Mandal, Avikarsha; Wozniak, Peter; Vauderwange, Oliver; Curticapean, Dan

    2016-09-01

    In the age data digitalization, important applications of optics and photonics based sensors and technology lie in the field of biometrics and image processing. Protecting user data in a safe and secure way is an essential task in this area. However, traditional cryptographic protocols rely heavily on computer aided computation. Secure protocols which rely only on human interactions are usually simpler to understand. In many scenarios development of such protocols are also important for ease of implementation and deployment. Visual cryptography (VC) is an encryption technique on images (or text) in which decryption is done by human visual system. In this technique, an image is encrypted into number of pieces (known as shares). When the printed shares are physically superimposed together, the image can be decrypted with human vision. Modern digital watermarking technologies can be combined with VC for image copyright protection where the shares can be watermarks (small identification) embedded in the image. Similarly, VC can be used for improving security of biometric authentication. This paper presents about design and implementation of a practical laboratory experiment based on the concept of VC for a course in media engineering. Specifically, our contribution deals with integration of VC in different schemes for applications like digital watermarking and biometric authentication in the field of optics and photonics. We describe theoretical concepts and propose our infrastructure for the experiment. Finally, we will evaluate the learning outcome of the experiment, performed by the students.

  6. Smart-system of distance learning of visually impaired people based on approaches of artificial intelligence

    Science.gov (United States)

    Samigulina, Galina A.; Shayakhmetova, Assem S.

    2016-11-01

    Research objective is the creation of intellectual innovative technology and information Smart-system of distance learning for visually impaired people. The organization of the available environment for receiving quality education for visually impaired people, their social adaptation in society are important and topical issues of modern education.The proposed Smart-system of distance learning for visually impaired people can significantly improve the efficiency and quality of education of this category of people. The scientific novelty of proposed Smart-system is using intelligent and statistical methods of processing multi-dimensional data, and taking into account psycho-physiological characteristics of perception and awareness learning information by visually impaired people.

  7. Learning about Locomotion Patterns from Visualizations: Effects of Presentation Format and Realism

    Science.gov (United States)

    Imhof, Birgit; Scheiter, Katharina; Gerjets, Peter

    2011-01-01

    The rapid development of computer graphics technology has made possible an easy integration of dynamic visualizations into computer-based learning environments. This study examines the relative effectiveness of dynamic visualizations, compared either to sequentially or simultaneously presented static visualizations. Moreover, the degree of realism…

  8. How Temporal and Spatial Aspects of Presenting Visualizations Affect Learning about Locomotion Patterns

    Science.gov (United States)

    Imhof, Birgit; Scheiter, Katharina; Edelmann, Jorg; Gerjets, Peter

    2012-01-01

    Two studies investigated the effectiveness of dynamic and static visualizations for a perceptual learning task (locomotion pattern classification). In Study 1, seventy-five students viewed either dynamic, static-sequential, or static-simultaneous visualizations. For tasks of intermediate difficulty, dynamic visualizations led to better…

  9. Lying aversion and prosocial behaviour

    CERN Document Server

    Biziou-van-Pol, Laura; Novaro, Arianna; Liberman, Andrés Occhipinti; Capraro, Valerio

    2015-01-01

    The focus of this paper is the moral conflict between lying aversion and prosociality. What does telling a white lie signal about a person's prosocial tendencies? How does believing a possibly untruthful message signal about a listener's prosocial tendencies? To answer these questions, we conducted a 2x3 experiment. In the first stage we measured altruistic tendencies using a Dictator Game and cooperative tendencies using a Prisoner's dilemma. In the second stage, we used a sender-receiver game to measure aversion to telling a Pareto white lie (i.e., a lie that helps both the liar and the listener), aversion to telling an altruistic white lie (i.e., a lie that helps the listener at the expense of the liar), and skepticism towards believing a possibly untruthful message. We found three major results: (i) both altruism and cooperation are positively correlated with aversion to telling a Pareto white lie; (ii) neither altruism nor cooperation are significantly correlated with aversion to telling an altruistic wh...

  10. An examination of ambiguity aversion

    Directory of Open Access Journals (Sweden)

    L. Robin Keller

    2007-12-01

    Full Text Available Ambiguity aversion has been widely observed in individuals' judgments. Using scenarios that are typical in decision analysis, we investigate ambiguity aversion for pairs of individuals. We examine risky and cautious shifts from individuals' original judgments to their judgments when they are paired up in dyads. In our experiment the participants were first asked to specify individually their willingness-to-pay for six monetary gambles. They were then paired at random into dyads, and were asked to specify their willingness-to-pay amount for the same gambles. The dyad's willingness-to-pay amount was to be shared equally by the two individuals. Of the six gambles in our experiment, one involved no ambiguity and the remaining five involved different degrees of ambiguity. We found that dyads exhibited risk aversion as well as ambiguity aversion. The majority of the dyads exhibited a cautious shift in the face of ambiguity, stating a smaller willingness-to-pay than the two individuals' average. Our study thus confirms the persistence of ambiguity aversion in a group setting and demonstrates the predominance of cautious shifts for dyads.

  11. Visual error augmentation enhances learning in three dimensions.

    Science.gov (United States)

    Sharp, Ian; Huang, Felix; Patton, James

    2011-09-02

    Because recent preliminary evidence points to the use of Error augmentation (EA) for motor learning enhancements, we visually enhanced deviations from a straight line path while subjects practiced a sensorimotor reversal task, similar to laparoscopic surgery. Our study asked 10 healthy subjects in two groups to perform targeted reaching in a simulated virtual reality environment, where the transformation of the hand position matrix was a complete reversal--rotated 180 degrees about an arbitrary axis (hence 2 of the 3 coordinates are reversed). Our data showed that after 500 practice trials, error-augmented-trained subjects reached the desired targets more quickly and with lower error (differences of 0.4 seconds and 0.5 cm Maximum Perpendicular Trajectory deviation) when compared to the control group. Furthermore, the manner in which subjects practiced was influenced by the error augmentation, resulting in more continuous motions for this group and smaller errors. Even with the extreme sensory discordance of a reversal, these data further support that distorted reality can promote more complete adaptation/learning when compared to regular training. Lastly, upon removing the flip all subjects quickly returned to baseline rapidly within 6 trials.

  12. Visual error augmentation enhances learning in three dimensions

    Directory of Open Access Journals (Sweden)

    Huang Felix

    2011-09-01

    Full Text Available Abstract Because recent preliminary evidence points to the use of Error augmentation (EA for motor learning enhancements, we visually enhanced deviations from a straight line path while subjects practiced a sensorimotor reversal task, similar to laparoscopic surgery. Our study asked 10 healthy subjects in two groups to perform targeted reaching in a simulated virtual reality environment, where the transformation of the hand position matrix was a complete reversal--rotated 180 degrees about an arbitrary axis (hence 2 of the 3 coordinates are reversed. Our data showed that after 500 practice trials, error-augmented-trained subjects reached the desired targets more quickly and with lower error (differences of 0.4 seconds and 0.5 cm Maximum Perpendicular Trajectory deviation when compared to the control group. Furthermore, the manner in which subjects practiced was influenced by the error augmentation, resulting in more continuous motions for this group and smaller errors. Even with the extreme sensory discordance of a reversal, these data further support that distorted reality can promote more complete adaptation/learning when compared to regular training. Lastly, upon removing the flip all subjects quickly returned to baseline rapidly within 6 trials.

  13. Sensorimotor Learning of Acupuncture Needle Manipulation Using Visual Feedback.

    Directory of Open Access Journals (Sweden)

    Won-Mo Jung

    Full Text Available Humans can acquire a wide variety of motor skills using sensory feedback pertaining to discrepancies between intended and actual movements. Acupuncture needle manipulation involves sophisticated hand movements and represents a fundamental skill for acupuncturists. We investigated whether untrained students could improve their motor performance during acupuncture needle manipulation using visual feedback (VF.Twenty-one untrained medical students were included, randomly divided into concurrent (n = 10 and post-trial (n = 11 VF groups. Both groups were trained in simple lift/thrusting techniques during session 1, and in complicated lift/thrusting techniques in session 2 (eight training trials per session. We compared the motion patterns and error magnitudes of pre- and post-training tests.During motion pattern analysis, both the concurrent and post-trial VF groups exhibited greater improvements in motion patterns during the complicated lifting/thrusting session. In the magnitude error analysis, both groups also exhibited reduced error magnitudes during the simple lifting/thrusting session. For the training period, the concurrent VF group exhibited reduced error magnitudes across all training trials, whereas the post-trial VF group was characterized by greater error magnitudes during initial trials, which gradually reduced during later trials.Our findings suggest that novices can improve the sophisticated hand movements required for acupuncture needle manipulation using sensorimotor learning with VF. Use of two types of VF can be beneficial for untrained students in terms of learning how to manipulate acupuncture needles, using either automatic or cognitive processes.

  14. Differences in risk aversion between young and older adults

    Directory of Open Access Journals (Sweden)

    Albert SM

    2012-02-01

    Full Text Available Steven M Albert1, John Duffy21Department of Behavioral and Community Health Sciences, 2Department of Economics, University of Pittsburgh, Pittsburgh, PA, USAAbstract: Research on decision-making strategies among younger and older adults suggests that older adults may be more risk averse than younger people in the case of potential losses. These results mostly come from experimental studies involving gambling paradigms. Since these paradigms involve substantial demands on memory and learning, differences in risk aversion or other features of decision making attributed to age may in fact reflect age-related declines in cognitive abilities. In the current study, older and younger adults completed a simpler, paired lottery choice task used in the experimental economics literature to elicit risk aversion. A similar approach was used to elicit participants' discount rates. The older adult group was more risk averse than the younger (P < 0.05 and had a higher discount rate (15.6%–21.0% versus 10.3%–15.5%, P < 0.01, indicating lower expected utility from future income. Risk aversion and implied discount rates were weakly correlated. It may be valuable to investigate developmental changes in neural correlates of decision making across the lifespan.Keywords: aging, decision making, risk, time preference, behavioral economics

  15. Aversive counterconditioning attenuates reward signalling in the ventral striatum

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    Anne Marije Kaag

    2016-08-01

    Full Text Available Appetitive conditioning refers to the process of learning cue-reward associations and is mediated by the mesocorticolimbic system. Appetitive conditioned responses are difficult to extinguish, especially for highly salient rewards such as food and drugs. We investigate whether aversive counterconditioning can alter reward reinstatement in the ventral striatum in healthy volunteers using functional Magnetic Resonance Imaging (fMRI. In the initial conditioning phase, two different stimuli were reinforced with a monetary reward. In the subsequent counterconditioning phase, one of these stimuli was paired with an aversive shock to the wrist. In the following extinction phase, none of the stimuli were reinforced. In the final reinstatement phase, reward was reinstated by informing the participants that the monetary gain could be doubled. Our fMRI data revealed that reward signalling in the ventral striatum and ventral tegmental area following reinstatement was smaller for the stimulus that was counterconditioned with an electrical shock, compared to the non-counterconditioned stimulus. A functional connectivity analysis showed that aversive counterconditioning strengthened striatal connectivity with the hippocampus and insula. These results suggest that reward signalling in the ventral striatum can be attenuated through aversive counterconditioning, possibly by concurrent retrieval of the aversive association through enhanced connectivity with hippocampus and insula.

  16. Pitch enhancement facilitates word learning across visual contexts

    Directory of Open Access Journals (Sweden)

    Piera eFilippi

    2014-12-01

    Full Text Available This study investigates word-learning using a new model that integrates three processes: a extracting a word out of a continuous sound sequence, b inferring its referential meanings in context, c mapping the segmented word onto its broader intended referent, such as other objects of the same semantic category, and to novel utterances. Previous work has examined the role of statistical learning and/or of prosody in each of these processes separately. Here, we combine these strands of investigation into a single experimental approach, in which participants viewed a photograph belonging to one of three semantic categories while hearing a complex, five-syllable utterance containing a one-syllable target word. Six between-subjects conditions were tested with 20 adult participants each. In condition 1, the only cue to word-meaning mapping was the co-occurrence of word and referents. This statistical cue was present in all conditions. In condition 2, the target word was sounded at a higher pitch. In condition 3, random one-syllable words were sounded at a higher pitch, creating an inconsistent cue. In condition 4, the duration of the target word was lengthened. In conditions 5 and 6, an extraneous acoustic cue and a visual cue were associated with the target word, respectively. Performance in this word-learning task was significantly higher than that observed with simple co-occurrence only when pitch prominence consistently marked the target word. We discuss implications for the intentional value of pitch marking as well as the relevance of our findings to language acquisition and language evolution.

  17. Deep generative learning of location-invariant visual word recognition.

    Science.gov (United States)

    Di Bono, Maria Grazia; Zorzi, Marco

    2013-01-01

    It is widely believed that orthographic processing implies an approximate, flexible coding of letter position, as shown by relative-position and transposition priming effects in visual word recognition. These findings have inspired alternative proposals about the representation of letter position, ranging from noisy coding across the ordinal positions to relative position coding based on open bigrams. This debate can be cast within the broader problem of learning location-invariant representations of written words, that is, a coding scheme abstracting the identity and position of letters (and combinations of letters) from their eye-centered (i.e., retinal) locations. We asked whether location-invariance would emerge from deep unsupervised learning on letter strings and what type of intermediate coding would emerge in the resulting hierarchical generative model. We trained a deep network with three hidden layers on an artificial dataset of letter strings presented at five possible retinal locations. Though word-level information (i.e., word identity) was never provided to the network during training, linear decoding from the activity of the deepest hidden layer yielded near-perfect accuracy in location-invariant word recognition. Conversely, decoding from lower layers yielded a large number of transposition errors. Analyses of emergent internal representations showed that word selectivity and location invariance increased as a function of layer depth. Word-tuning and location-invariance were found at the level of single neurons, but there was no evidence for bigram coding. Finally, the distributed internal representation of words at the deepest layer showed higher similarity to the representation elicited by the two exterior letters than by other combinations of two contiguous letters, in agreement with the hypothesis that word edges have special status. These results reveal that the efficient coding of written words-which was the model's learning objective

  18. Deep generative learning of location-invariant visual word recognition

    Directory of Open Access Journals (Sweden)

    Maria Grazia eDi Bono

    2013-09-01

    Full Text Available It is widely believed that orthographic processing implies an approximate, flexible coding of letter position, as shown by relative-position and transposition priming effects in visual word recognition. These findings have inspired alternative proposals about the representation of letter position, ranging from noisy coding across the ordinal positions to relative position coding based on open bigrams. This debate can be cast within the broader problem of learning location-invariant representations of written words, that is, a coding scheme abstracting the identity and position of letters (and combinations of letters from their eye-centred (i.e., retinal locations. We asked whether location-invariance would emerge from deep unsupervised learning on letter strings and what type of intermediate coding would emerge in the resulting hierarchical generative model. We trained a deep network with three hidden layers on an artificial dataset of letter strings presented at five possible retinal locations. Though word-level information (i.e., word identity was never provided to the network during training, linear decoding from the activity of the deepest hidden layer yielded near-perfect accuracy in location-invariant word recognition. Conversely, decoding from lower layers yielded a large number of transposition errors. Analyses of emergent internal representations showed that word selectivity and location invariance increased as a function of layer depth. Conversely, there was no evidence for bigram coding. Finally, the distributed internal representation of words at the deepest layer showed higher similarity to the representation elicited by the two exterior letters than by other combinations of two contiguous letters, in agreement with the hypothesis that word edges have special status. These results reveal that the efficient coding of written words – which was the model’s learning objective – is largely based on letter-level information.

  19. Aversive behavior induced by optogenetic inactivation of ventral tegmental area dopamine neurons is mediated by dopamine D2 receptors in the nucleus accumbens.

    Science.gov (United States)

    Danjo, Teruko; Yoshimi, Kenji; Funabiki, Kazuo; Yawata, Satoshi; Nakanishi, Shigetada

    2014-04-29

    Dopamine (DA) transmission from the ventral tegmental area (VTA) is critical for controlling both rewarding and aversive behaviors. The transient silencing of DA neurons is one of the responses to aversive stimuli, but its consequences and neural mechanisms regarding aversive responses and learning have largely remained elusive. Here, we report that optogenetic inactivation of VTA DA neurons promptly down-regulated DA levels and induced up-regulation of the neural activity in the nucleus accumbens (NAc) as evaluated by Fos expression. This optogenetic suppression of DA neuron firing immediately evoked aversive responses to the previously preferred dark room and led to aversive learning toward the optogenetically conditioned place. Importantly, this place aversion was abolished by knockdown of dopamine D2 receptors but not by that of D1 receptors in the NAc. Silencing of DA neurons in the VTA was thus indispensable for inducing aversive responses and learning through dopamine D2 receptors in the NAc.

  20. You see what you have learned. Evidence for an interrelation of associative learning and visual selective attention.

    Science.gov (United States)

    Feldmann-Wüstefeld, Tobias; Uengoer, Metin; Schubö, Anna

    2015-11-01

    Besides visual salience and observers' current intention, prior learning experience may influence deployment of visual attention. Associative learning models postulate that observers pay more attention to stimuli previously experienced as reliable predictors of specific outcomes. To investigate the impact of learning experience on deployment of attention, we combined an associative learning task with a visual search task and measured event-related potentials of the EEG as neural markers of attention deployment. In the learning task, participants categorized stimuli varying in color/shape with only one dimension being predictive of category membership. In the search task, participants searched a shape target while disregarding irrelevant color distractors. Behavioral results showed that color distractors impaired performance to a greater degree when color rather than shape was predictive in the learning task. Neurophysiological results show that the amplified distraction was due to differential attention deployment (N2pc). Experiment 2 showed that when color was predictive for learning, color distractors captured more attention in the search task (ND component) and more suppression of color distractor was required (PD component). The present results thus demonstrate that priority in visual attention is biased toward predictive stimuli, which allows learning experience to shape selection. We also show that learning experience can overrule strong top-down control (blocked tasks, Experiment 3) and that learning experience has a longer-term effect on attention deployment (tasks on two successive days, Experiment 4).

  1. Exploring Antecedents of Performance Differences on Visual and Verbal Test Items: Learning Styles versus Aptitude

    Science.gov (United States)

    Bacon, Donald R.; Hartley, Steven W.

    2015-01-01

    Many educators and researchers have suggested that some students learn more effectively with visual stimuli (e.g., pictures, graphs), whereas others learn more effectively with verbal information (e.g., text) (Felder & Brent, 2005). In two studies, the present research seeks to improve popular self-reported (indirect) learning style measures…

  2. Efficacy of Simulation-Based Learning of Electronics Using Visualization and Manipulation

    Science.gov (United States)

    Chen, Yu-Lung; Hong, Yu-Ru; Sung, Yao-Ting; Chang, Kuo-En

    2011-01-01

    Software for simulation-based learning of electronics was implemented to help learners understand complex and abstract concepts through observing external representations and exploring concept models. The software comprises modules for visualization and simulative manipulation. Differences in learning performance of using the learning software…

  3. Mobile Learning and the Visual Web, Oh My! Nutrition Education in the 21st Century

    Science.gov (United States)

    Schuster, Ellen

    2012-01-01

    Technology is rapidly changing how our program participants learn in school and for their personal improvement. Extension educators who deliver nutrition program will want to be aware of the technology trends that are driving these changes. Blended learning, mobile learning, the visual Web, and the gamification of health are approaches to consider…

  4. The Role of Visual Learning in Improving Students' High-Order Thinking Skills

    Science.gov (United States)

    Raiyn, Jamal

    2016-01-01

    Various concepts have been introduced to improve students' analytical thinking skills based on problem based learning (PBL). This paper introduces a new concept to increase student's analytical thinking skills based on a visual learning strategy. Such a strategy has three fundamental components: a teacher, a student, and a learning process. The…

  5. Neural correlates of context-dependent feature conjunction learning in visual search tasks.

    Science.gov (United States)

    Reavis, Eric A; Frank, Sebastian M; Greenlee, Mark W; Tse, Peter U

    2016-06-01

    Many perceptual learning experiments show that repeated exposure to a basic visual feature such as a specific orientation or spatial frequency can modify perception of that feature, and that those perceptual changes are associated with changes in neural tuning early in visual processing. Such perceptual learning effects thus exert a bottom-up influence on subsequent stimulus processing, independent of task-demands or endogenous influences (e.g., volitional attention). However, it is unclear whether such bottom-up changes in perception can occur as more complex stimuli such as conjunctions of visual features are learned. It is not known whether changes in the efficiency with which people learn to process feature conjunctions in a task (e.g., visual search) reflect true bottom-up perceptual learning versus top-down, task-related learning (e.g., learning better control of endogenous attention). Here we show that feature conjunction learning in visual search leads to bottom-up changes in stimulus processing. First, using fMRI, we demonstrate that conjunction learning in visual search has a distinct neural signature: an increase in target-evoked activity relative to distractor-evoked activity (i.e., a relative increase in target salience). Second, we demonstrate that after learning, this neural signature is still evident even when participants passively view learned stimuli while performing an unrelated, attention-demanding task. This suggests that conjunction learning results in altered bottom-up perceptual processing of the learned conjunction stimuli (i.e., a perceptual change independent of the task). We further show that the acquired change in target-evoked activity is contextually dependent on the presence of distractors, suggesting that search array Gestalts are learned. Hum Brain Mapp 37:2319-2330, 2016. © 2016 Wiley Periodicals, Inc.

  6. Distinct midbrain and habenula pathways are involved in processing aversive events in humans.

    Science.gov (United States)

    Hennigan, Kelly; D'Ardenne, Kimberlee; McClure, Samuel M

    2015-01-01

    Emerging evidence implicates the midbrain dopamine system and its interactions with the lateral habenula in processing aversive information and learning to avoid negative outcomes. We examined neural responses to unexpected, aversive events using methods specialized for imaging the midbrain and habenula in humans. Robust activation to aversive relative to neutral events was observed in the habenula and two regions within the ventral midbrain: one located within the ventral tegmental area (VTA) and the other in the substantia nigra (SN). Aversive processing increased functional connectivity between the VTA and the habenula, putamen, and medial prefrontal cortex, whereas the SN exhibited a different pattern of functional connectivity. Our findings provide evidence for a network comprising the VTA and SN, the habenula, and mesocorticolimbic structures that supports processing aversive events in humans.

  7. Optimal portfolio choice under loss aversion

    NARCIS (Netherlands)

    A.B. Berkelaar (Arjan); R.R.P. Kouwenberg (Roy)

    2000-01-01

    textabstractProspect theory and loss aversion play a dominant role in behavioral finance. In this paper we derive closed-form solutions for optimal portfolio choice under loss aversion. When confronted with gains a loss averse investor behaves similar to a portfolio insurer. When confronted with los

  8. Aversive racism in Spain: testing the theory

    NARCIS (Netherlands)

    Wojcieszak, M.

    2015-01-01

    This study applies the aversive racism framework to Spain and tests whether aversive racism depends on intergroup contact. Relying on a 3 (qualifications) by 3 (ethnicity) experiment, this study finds that aversive racism is especially pronounced against the Mexican job applicant, and emerges among

  9. Aversive Stimulation -- Criteria for Application.

    Science.gov (United States)

    O'Donnell, Patrick A.; Ohlson, Glenn A.

    Criteria for applying aversive stimulation with severely handicapped children are examined, and practical and ethical issues are considered. Factors seen to influence punishment outcomes include timing, intensity, and schedule of reinforcement. Suggested is the need for further research on the comparative effectiveness of positive and negative…

  10. Enhancing mobile phones for people with visual impairments through haptic icons: the effect of learning processes.

    Science.gov (United States)

    Galdón, Pedro Maria; Madrid, R Ignacio; De La Rubia-Cuestas, Ernesto J; Diaz-Estrella, Antonio; Gonzalez, Lourdes

    2013-01-01

    We report the results of a study on the learnability ofhaptic icons used in a system for incoming-call identification in mobile phones. The aim was to explore the feasibility of using haptic icons to create new assistive technologies for people with visual impairments. We compared the performance and satisfaction of users with different visual capacities (visually impaired vs. sighted) and using different learning processes (unimodal vs. multimodal). A better recognition rate and user experience were observed for the visually impaired than for sighted users and for multimodal rather than unimodal learning processes.

  11. Genotypic influence on aversive conditioning in honeybees, using a novel thermal reinforcement procedure.

    Science.gov (United States)

    Junca, Pierre; Carcaud, Julie; Moulin, Sibyle; Garnery, Lionel; Sandoz, Jean-Christophe

    2014-01-01

    In Pavlovian conditioning, animals learn to associate initially neutral stimuli with positive or negative outcomes, leading to appetitive and aversive learning respectively. The honeybee (Apis mellifera) is a prominent invertebrate model for studying both versions of olfactory learning and for unraveling the influence of genotype. As a queen bee mates with about 15 males, her worker offspring belong to as many, genetically-different patrilines. While the genetic dependency of appetitive learning is well established in bees, it is not the case for aversive learning, as a robust protocol was only developed recently. In the original conditioning of the sting extension response (SER), bees learn to associate an odor (conditioned stimulus - CS) with an electric shock (unconditioned stimulus - US). This US is however not a natural stimulus for bees, which may represent a potential caveat for dissecting the genetics underlying aversive learning. We thus first tested heat as a potential new US for SER conditioning. We show that thermal stimulation of several sensory structures on the bee's body triggers the SER, in a temperature-dependent manner. Moreover, heat applied to the antennae, mouthparts or legs is an efficient US for SER conditioning. Then, using microsatellite analysis, we analyzed heat sensitivity and aversive learning performances in ten worker patrilines issued from a naturally inseminated queen. We demonstrate a strong influence of genotype on aversive learning, possibly indicating the existence of a genetic determinism of this capacity. Such determinism could be instrumental for efficient task partitioning within the hive.

  12. Genotypic influence on aversive conditioning in honeybees, using a novel thermal reinforcement procedure.

    Directory of Open Access Journals (Sweden)

    Pierre Junca

    Full Text Available In Pavlovian conditioning, animals learn to associate initially neutral stimuli with positive or negative outcomes, leading to appetitive and aversive learning respectively. The honeybee (Apis mellifera is a prominent invertebrate model for studying both versions of olfactory learning and for unraveling the influence of genotype. As a queen bee mates with about 15 males, her worker offspring belong to as many, genetically-different patrilines. While the genetic dependency of appetitive learning is well established in bees, it is not the case for aversive learning, as a robust protocol was only developed recently. In the original conditioning of the sting extension response (SER, bees learn to associate an odor (conditioned stimulus - CS with an electric shock (unconditioned stimulus - US. This US is however not a natural stimulus for bees, which may represent a potential caveat for dissecting the genetics underlying aversive learning. We thus first tested heat as a potential new US for SER conditioning. We show that thermal stimulation of several sensory structures on the bee's body triggers the SER, in a temperature-dependent manner. Moreover, heat applied to the antennae, mouthparts or legs is an efficient US for SER conditioning. Then, using microsatellite analysis, we analyzed heat sensitivity and aversive learning performances in ten worker patrilines issued from a naturally inseminated queen. We demonstrate a strong influence of genotype on aversive learning, possibly indicating the existence of a genetic determinism of this capacity. Such determinism could be instrumental for efficient task partitioning within the hive.

  13. A real-time articulatory visual feedback approach with target presentation for second language pronunciation learning.

    Science.gov (United States)

    Suemitsu, Atsuo; Dang, Jianwu; Ito, Takayuki; Tiede, Mark

    2015-10-01

    Articulatory information can support learning or remediating pronunciation of a second language (L2). This paper describes an electromagnetic articulometer-based visual-feedback approach using an articulatory target presented in real-time to facilitate L2 pronunciation learning. This approach trains learners to adjust articulatory positions to match targets for a L2 vowel estimated from productions of vowels that overlap in both L1 and L2. Training of Japanese learners for the American English vowel /æ/ that included visual training improved its pronunciation regardless of whether audio training was also included. Articulatory visual feedback is shown to be an effective method for facilitating L2 pronunciation learning.

  14. Drosophila Mushroom Bodies Are Dispensable for Visual, Tactile, and Motor Learning

    Science.gov (United States)

    Wolf, Reinhard; Wittig, Tobias; Liu, Li; Wustmann, Gerold; Eyding, Dirk; Heisenberg, Martin

    1998-01-01

    A total of 18 associative learning/memory tests have been applied to Drosophila melanogaster flies lacking mushroom bodies. Only in paradigms involving chemosensory cues as conditioned stimuli have flies been found to be compromised by a block in the mushroom body pathway. Among the learning tasks not requiring these structures are a case of motor learning (yaw torque/heat), a test of the fly’s spatial orientation in total darkness, conditioned courtship suppression by mated females, and nine different examples of visual learning. The latter used the reinforcers of heat, visual oscillations, mechanical shaking, or sucrose, and as conditioned stimuli, color, intensity contrast, as well as stationary and moving visual patterns. No forms of consolidated memory have been tested in mushroom body-less flies. With respect to short-term memory the mushroom bodies of Drosophila are specially required for chemosensory learning tasks, but not for associative learning and memory in general. PMID:10454381

  15. The effect of emotional state on the learning of visual skills

    Directory of Open Access Journals (Sweden)

    Caroline E. Mills

    2014-02-01

    Full Text Available The findings of the present study suggest that anxiety, to some extent, influences the learning of focusing, tracking and vergence. Curiosity, on the other hand, did not influence the learning of any of the visual skills under investigation in the present study. Good visual skills are essential components in achieving educational, economic and social success, and independence. A need has been identified to determine whether the visual skills of students can be improved through sports vision exercises, and whether the potential benefits derived from these sports vision exercises could be influenced by emotional states such as anxiety and curiosity. Since little research has been conducted on the relationship between the learning of visual skills and the presence of these two emotional states, one needs to determine the extent to which anxiety and curiosity affect the learning of visual skills. For the purposes of this study, a quantitative research methodology was used. A quasi-experimental approach was employed to collect data on visual skills and the effects of sports vision exercises on these visual skills. The sample consisted of second-year physiology students (n = 204 and included students of genders, various ethnicities, and ages ranging from 18 to 27 years of age. Anxiety and curiosity were measured by using the State-Trait Personality Inventory (STPI, whilst the visual skills of the participants were measured by using a battery of visual skills tests. The results proved that sports vision exercises can improve some visual skills. It should, however, be noted that anxiety levels must be controlled when administering this training. The findings of the present study suggest that anxiety, to some extent, negatively influences the learning of focusing, tracking and vergence. Curiosity on the other hand did not influence the learning of any of the visual skills under investigation in the present study.

  16. Tiger salamanders' (Ambystoma tigrinum) response learning and usage of visual cues.

    Science.gov (United States)

    Kundey, Shannon M A; Millar, Roberto; McPherson, Justin; Gonzalez, Maya; Fitz, Aleyna; Allen, Chadbourne

    2016-05-01

    We explored tiger salamanders' (Ambystoma tigrinum) learning to execute a response within a maze as proximal visual cue conditions varied. In Experiment 1, salamanders learned to turn consistently in a T-maze for reinforcement before the maze was rotated. All learned the initial task and executed the trained turn during test, suggesting that they learned to demonstrate the reinforced response during training and continued to perform it during test. In a second experiment utilizing a similar procedure, two visual cues were placed consistently at the maze junction. Salamanders were reinforced for turning towards one cue. Cue placement was reversed during test. All learned the initial task, but executed the trained turn rather than turning towards the visual cue during test, evidencing response learning. In Experiment 3, we investigated whether a compound visual cue could control salamanders' behaviour when it was the only cue predictive of reinforcement in a cross-maze by varying start position and cue placement. All learned to turn in the direction indicated by the compound visual cue, indicating that visual cues can come to control their behaviour. Following training, testing revealed that salamanders attended to stimuli foreground over background features. Overall, these results suggest that salamanders learn to execute responses over learning to use visual cues but can use visual cues if required. Our success with this paradigm offers the potential in future studies to explore salamanders' cognition further, as well as to shed light on how features of the tiger salamanders' life history (e.g. hibernation and metamorphosis) impact cognition.

  17. Neural Activations during Visual Sequence Learning Leave a Trace in Post-Training Spontaneous EEG

    OpenAIRE

    2013-01-01

    Recent EEG studies have shown that implicit learning involving specific cortical circuits results in an enduring local trace manifested as local changes in spectral power. Here we used a well characterized visual sequence learning task and high density-(hd-)EEG recording to determine whether also declarative learning leaves a post-task, local change in the resting state oscillatory activity in the areas involved in the learning process. Thus, we recorded hd-EEG in normal subjects before, duri...

  18. A mouse model of visual perceptual learning reveals alterations in neuronal coding and dendritic spine density in the visual cortex

    Directory of Open Access Journals (Sweden)

    Yan eWang

    2016-03-01

    Full Text Available Visual perceptual learning (VPL can improve spatial vision in normally sighted and visually impaired individuals. Although previous studies of humans and large animals have explored the neural basis of VPL, elucidation of the underlying cellular and molecular mechanisms remains a challenge. Owing to the advantages of molecular genetic and optogenetic manipulations, the mouse is a promising model for providing a mechanistic understanding of VPL. Here, we thoroughly evaluated the effects and properties of VPL on spatial vision in C57BL/6J mice using a two-alternative, forced-choice visual water task. Briefly, the mice underwent prolonged training at near the individual threshold of contrast or spatial frequency (SF for pattern discrimination or visual detection for 35 consecutive days. Following training, the contrast-threshold trained mice showed an 87% improvement in contrast sensitivity (CS and a 55% gain in visual acuity (VA. Similarly, the SF-threshold trained mice exhibited comparable and long-lasting improvements in VA and significant gains in CS over a wide range of SFs. Furthermore, learning largely transferred across eyes and stimulus orientations. Interestingly, learning could transfer from a pattern discrimination task to a visual detection task, but not vice versa. We validated that this VPL fully restored VA in adult amblyopic mice and old mice. Taken together, these data indicate that mice, as a species, exhibit reliable VPL. Intrinsic signal optical imaging revealed that mice with perceptual training had higher cut-off SFs in primary visual cortex (V1 than those without perceptual training. Moreover, perceptual training induced an increase in the dendritic spine density in layer 2/3 pyramidal neurons of V1. These results indicated functional and structural alterations in V1 during VPL. Overall, our VPL mouse model will provide a platform for investigating the neurobiological basis of VPL.

  19. Visualization

    OpenAIRE

    Balon, Andreja

    1990-01-01

    The present thesis entails the field of visualization which is divided into visualization along traditional lines and visualization in computer science. As the psychological aspect of image is of vital importance for visualization, it is shortly described in the beginning. Visualization in computer science is divided into three main fields: scientific visualization, program visualization and visual programming. An explanation and examples of approach to applications are given for each field....

  20. Contrasting Effects of Histone Deacetylase Inhibitors on Reward and Aversive Olfactory Memories in the Honey Bee

    Directory of Open Access Journals (Sweden)

    Gabrielle A Lockett

    2014-06-01

    Full Text Available Much of what we have learnt from rodent models about the essential role of epigenetic processes in brain plasticity has made use of aversive learning, yet the role of histone acetylation in aversive memory in the honey bee, a popular invertebrate model for both memory and epigenetics, was previously unknown. We examined the effects of histone deacetylase (HDAC inhibition on both aversive and reward olfactory associative learning in a discrimination proboscis extension reflex (PER assay. We report that treatment with the HDAC inhibitors APHA compound 8 (C8, phenylbutyrate (PB or sodium butyrate (NaB impaired discrimination memory due to impairment of aversive memory in a dose-dependent manner, while simultaneously having no effect on reward memory. Treatment with C8 1 h before training, 1 h after training or 1 h before testing, impaired aversive but not reward memory at test. C8 treatment 1 h before training also improved aversive but not reward learning during training. PB treatment only impaired aversive memory at test when administered 1 h after training, suggesting an effect on memory consolidation specifically. Specific impairment of aversive memory (but not reward memory by HDAC inhibiting compounds was robust, reproducible, occurred following treatment with three drugs targeting the same mechanism, and is likely to be genuinely due to alterations to memory as sucrose sensitivity and locomotion were unaffected by HDAC inhibitor treatment. This pharmacological dissection of memory highlights the involvement of histone acetylation in aversive memory in the honey bee, and expands our knowledge of epigenetic control of neural plasticity in invertebrates.

  1. Two different motor learning mechanisms contribute to learning reaching movements in a rotated visual environment.

    Science.gov (United States)

    Chu, Virginia Way Tong; Sanger, Terence David

    2014-01-01

    Practice of movement in virtual-reality and other artificially altered environments has been proposed as a method for rehabilitation following neurological injury and for training new skills in healthy humans.  For such training to be useful, there must be transfer of learning from the artificial environment to the performance of desired skills in the natural environment.  Therefore an important assumption of such methods is that practice in the altered environment engages the same learning and plasticity mechanisms that are required for skill performance in the natural environment.  We test the hypothesis that transfer of learning may fail because the learning and plasticity mechanism that adapts to the altered environment is different from the learning mechanism required for improvement of motor skill.  In this paper, we propose that a model that separates skill learning and environmental adaptation is necessary to explain the learning and aftereffects that are observed in virtual reality experiments.  In particular, we studied the condition where practice in the altered environment should lead to correct skill performance in the original environment. Our 2-mechanism model predicts that aftereffects will still be observed when returning to the original environment, indicating a lack of skill transfer from the artificial environment to the original environment. To illustrate the model prediction, we tested 10 healthy participants on the interaction between a simple overlearned motor skill (straight hand movements to targets in different directions) and an artificially altered visuomotor environment (rotation of visual feedback of the results of movement).  As predicted by the models, participants show adaptation to the altered environment and after-effects on return to the baseline environment even when practice in the altered environment should have led to correct skill performance.  The presence of aftereffect under all conditions that involved changes in

  2. Learning Enhances Sensory and Multiple Non-sensory Representations in Primary Visual Cortex.

    Science.gov (United States)

    Poort, Jasper; Khan, Adil G; Pachitariu, Marius; Nemri, Abdellatif; Orsolic, Ivana; Krupic, Julija; Bauza, Marius; Sahani, Maneesh; Keller, Georg B; Mrsic-Flogel, Thomas D; Hofer, Sonja B

    2015-06-17

    We determined how learning modifies neural representations in primary visual cortex (V1) during acquisition of a visually guided behavioral task. We imaged the activity of the same layer 2/3 neuronal populations as mice learned to discriminate two visual patterns while running through a virtual corridor, where one pattern was rewarded. Improvements in behavioral performance were closely associated with increasingly distinguishable population-level representations of task-relevant stimuli, as a result of stabilization of existing and recruitment of new neurons selective for these stimuli. These effects correlated with the appearance of multiple task-dependent signals during learning: those that increased neuronal selectivity across the population when expert animals engaged in the task, and those reflecting anticipation or behavioral choices specifically in neuronal subsets preferring the rewarded stimulus. Therefore, learning engages diverse mechanisms that modify sensory and non-sensory representations in V1 to adjust its processing to task requirements and the behavioral relevance of visual stimuli.

  3. The DeepTree Exhibit: Visualizing the Tree of Life to Facilitate Informal Learning.

    Science.gov (United States)

    Block, F; Horn, M S; Phillips, B C; Diamond, J; Evans, E M; Shen, Chia

    2012-12-01

    In this paper, we present the DeepTree exhibit, a multi-user, multi-touch interactive visualization of the Tree of Life. We developed DeepTree to facilitate collaborative learning of evolutionary concepts. We will describe an iterative process in which a team of computer scientists, learning scientists, biologists, and museum curators worked together throughout design, development, and evaluation. We present the importance of designing the interactions and the visualization hand-in-hand in order to facilitate active learning. The outcome of this process is a fractal-based tree layout that reduces visual complexity while being able to capture all life on earth; a custom rendering and navigation engine that prioritizes visual appeal and smooth fly-through; and a multi-user interface that encourages collaborative exploration while offering guided discovery. We present an evaluation showing that the large dataset encouraged free exploration, triggers emotional responses, and facilitates visitor engagement and informal learning.

  4. Reduction in the retinotopic early visual cortex with normal aging and magnitude of perceptual learning.

    Science.gov (United States)

    Chang, Li-Hung; Yotsumoto, Yuko; Salat, David H; Andersen, George J; Watanabe, Takeo; Sasaki, Yuka

    2015-01-01

    Although normal aging is known to reduce cortical structures globally, the effects of aging on local structures and functions of early visual cortex are less understood. Here, using standard retinotopic mapping and magnetic resonance imaging morphologic analyses, we investigated whether aging affects areal size of the early visual cortex, which were retinotopically localized, and whether those morphologic measures were associated with individual performance on visual perceptual learning. First, significant age-associated reduction was found in the areal size of V1, V2, and V3. Second, individual ability of visual perceptual learning was significantly correlated with areal size of V3 in older adults. These results demonstrate that aging changes local structures of the early visual cortex, and the degree of change may be associated with individual visual plasticity.

  5. Sparse representation, modeling and learning in visual recognition theory, algorithms and applications

    CERN Document Server

    Cheng, Hong

    2015-01-01

    This unique text/reference presents a comprehensive review of the state of the art in sparse representations, modeling and learning. The book examines both the theoretical foundations and details of algorithm implementation, highlighting the practical application of compressed sensing research in visual recognition and computer vision. Topics and features: provides a thorough introduction to the fundamentals of sparse representation, modeling and learning, and the application of these techniques in visual recognition; describes sparse recovery approaches, robust and efficient sparse represen

  6. Learning visual balance from large-scale datasets of aesthetically highly rated images

    Science.gov (United States)

    Jahanian, Ali; Vishwanathan, S. V. N.; Allebach, Jan P.

    2015-03-01

    The concept of visual balance is innate for humans, and influences how we perceive visual aesthetics and cognize harmony. Although visual balance is a vital principle of design and taught in schools of designs, it is barely quantified. On the other hand, with emergence of automantic/semi-automatic visual designs for self-publishing, learning visual balance and computationally modeling it, may escalate aesthetics of such designs. In this paper, we present how questing for understanding visual balance inspired us to revisit one of the well-known theories in visual arts, the so called theory of "visual rightness", elucidated by Arnheim. We define Arnheim's hypothesis as a design mining problem with the goal of learning visual balance from work of professionals. We collected a dataset of 120K images that are aesthetically highly rated, from a professional photography website. We then computed factors that contribute to visual balance based on the notion of visual saliency. We fitted a mixture of Gaussians to the saliency maps of the images, and obtained the hotspots of the images. Our inferred Gaussians align with Arnheim's hotspots, and confirm his theory. Moreover, the results support the viability of the center of mass, symmetry, as well as the Rule of Thirds in our dataset.

  7. A Comparison of the Sexual Learning Experiences of Visually Impaired and Sighted Women.

    Science.gov (United States)

    Welbourne, Ann; And Others

    1983-01-01

    A comparison of the sexual learning experiences of 39 visually impaired women with a matched group of sighted women revealed that visually impaired women had significantly lower sex knowledge scores and obtained their information at a somewhat later age. (Author/CL)

  8. Visual Hybrid Development Learning System (VHDLS) Framework for Children with Autism

    Science.gov (United States)

    Banire, Bilikis; Jomhari, Nazean; Ahmad, Rodina

    2015-01-01

    The effect of education on children with autism serves as a relative cure for their deficits. As a result of this, they require special techniques to gain their attention and interest in learning as compared to typical children. Several studies have shown that these children are visual learners. In this study, we proposed a Visual Hybrid…

  9. Preparing Content-Rich Learning Environments with VPython and Excel, Controlled by Visual Basic for Applications

    Science.gov (United States)

    Prayaga, Chandra

    2008-01-01

    A simple interface between VPython and Microsoft (MS) Office products such as Word and Excel, controlled by Visual Basic for Applications, is described. The interface allows the preparation of content-rich, interactive learning environments by taking advantage of the three-dimensional (3D) visualization capabilities of VPython and the GUI…

  10. HD-MTL: Hierarchical Deep Multi-Task Learning for Large-Scale Visual Recognition.

    Science.gov (United States)

    Fan, Jianping; Zhao, Tianyi; Kuang, Zhenzhong; Zheng, Yu; Zhang, Ji; Yu, Jun; Peng, Jinye

    2017-02-09

    In this paper, a hierarchical deep multi-task learning (HD-MTL) algorithm is developed to support large-scale visual recognition (e.g., recognizing thousands or even tens of thousands of atomic object classes automatically). First, multiple sets of multi-level deep features are extracted from different layers of deep convolutional neural networks (deep CNNs), and they are used to achieve more effective accomplishment of the coarseto- fine tasks for hierarchical visual recognition. A visual tree is then learned by assigning the visually-similar atomic object classes with similar learning complexities into the same group, which can provide a good environment for determining the interrelated learning tasks automatically. By leveraging the inter-task relatedness (inter-class similarities) to learn more discriminative group-specific deep representations, our deep multi-task learning algorithm can train more discriminative node classifiers for distinguishing the visually-similar atomic object classes effectively. Our hierarchical deep multi-task learning (HD-MTL) algorithm can integrate two discriminative regularization terms to control the inter-level error propagation effectively, and it can provide an end-to-end approach for jointly learning more representative deep CNNs (for image representation) and more discriminative tree classifier (for large-scale visual recognition) and updating them simultaneously. Our incremental deep learning algorithms can effectively adapt both the deep CNNs and the tree classifier to the new training images and the new object classes. Our experimental results have demonstrated that our HD-MTL algorithm can achieve very competitive results on improving the accuracy rates for large-scale visual recognition.

  11. Risk aversion and religious behaviour

    DEFF Research Database (Denmark)

    Nielsen, Jytte Seested; Bech, Mickael; Christensen, Kaare

    2017-01-01

    Economics offers an analytical framework to consider human behaviour including religious behaviour. Within the realm of Expected Utility Theory, religious belief and activity could be interpreted as an insurance both for current life events and for afterlife rewards. Based on that framework, we...... and religious behaviour is driven by the subgroup of individuals who believe in an afterlife. In addition, when re-analysing our results using panel data analyses which cancel out shared factors among twin pairs, we find that the correlation found between risk aversion and religious behaviour is no longer...... significant indicating that other factors might explain differences in religious behaviour. Caution is needed in the interpretation of our results as the insignificant association between risk aversion and religious behaviour in the panel data analyses potentially might be due to measurement error causing...

  12. Formation of 17-18 yrs age girl students’ visual performance by means of visual training at stage of adaptation to learning loads

    Directory of Open Access Journals (Sweden)

    Bondarenko S.V.

    2015-04-01

    Full Text Available Purpose: substantiation of health related training influence of basketball and volleyball elements on functional state of 1 st year students’ visual analyzers in period of adaptation to learning loads with expressed visual component. Material: in experiment 29 students of 17-18 year age without visual pathologies participated. Indicators of visual performance were determined by correction table of Tagayeva and processed by Weston methodic. Accommodative function was tested by method of mechanical proximetry. Results: the authors worked out and tested two programs of visual training. Influence of visual trainings on visual performance’s main components (quickness, quality, integral indicators was studied as well as eye’s accommodative function (by dynamic of position of the nearest point of clear vision. Conclusions: Application of visual trainings at physical education classes permits to improve indicators of visual analyzer’s performance as well as minimize negative influence of intensive learning loads on eye’ accommodative function.

  13. The cerebellum and visual perceptual learning: evidence from a motion extrapolation task.

    Science.gov (United States)

    Deluca, Cristina; Golzar, Ashkan; Santandrea, Elisa; Lo Gerfo, Emanuele; Eštočinová, Jana; Moretto, Giuseppe; Fiaschi, Antonio; Panzeri, Marta; Mariotti, Caterina; Tinazzi, Michele; Chelazzi, Leonardo

    2014-09-01

    Visual perceptual learning is widely assumed to reflect plastic changes occurring along the cerebro-cortical visual pathways, including at the earliest stages of processing, though increasing evidence indicates that higher-level brain areas are also involved. Here we addressed the possibility that the cerebellum plays an important role in visual perceptual learning. Within the realm of motor control, the cerebellum supports learning of new skills and recalibration of motor commands when movement execution is consistently perturbed (adaptation). Growing evidence indicates that the cerebellum is also involved in cognition and mediates forms of cognitive learning. Therefore, the obvious question arises whether the cerebellum might play a similar role in learning and adaptation within the perceptual domain. We explored a possible deficit in visual perceptual learning (and adaptation) in patients with cerebellar damage using variants of a novel motion extrapolation, psychophysical paradigm. Compared to their age- and gender-matched controls, patients with focal damage to the posterior (but not the anterior) cerebellum showed strongly diminished learning, in terms of both rate and amount of improvement over time. Consistent with a double-dissociation pattern, patients with focal damage to the anterior cerebellum instead showed more severe clinical motor deficits, indicative of a distinct role of the anterior cerebellum in the motor domain. The collected evidence demonstrates that a pure form of slow-incremental visual perceptual learning is crucially dependent on the intact cerebellum, bearing the notion that the human cerebellum acts as a learning device for motor, cognitive and perceptual functions. We interpret the deficit in terms of an inability to fine-tune predictive models of the incoming flow of visual perceptual input over time. Moreover, our results suggest a strong dissociation between the role of different portions of the cerebellum in motor versus

  14. Leverage Aversion and Risk Parity

    DEFF Research Database (Denmark)

    Asness, Clifford; Frazzini, Andrea; Heje Pedersen, Lasse

    2012-01-01

    The authors show that leverage aversion changes the predictions of modern portfolio theory: Safer assets must offer higher risk-adjusted returns than riskier assets. Consuming the high risk-adjusted returns of safer assets requires leverage, creating an opportunity for investors with the ability...... to apply leverage. Risk parity portfolios exploit this opportunity by equalizing the risk allocation across asset classes, thus overweighting safer assets relative to their weight in the market portfolio....

  15. Medial prefrontal cortex dopamine controls the persistent storage of aversive memories

    OpenAIRE

    María Carolina Gonzalez; Cecilia Paula Kramar; Micol eTomaiuolo; Cynthia eKatche; Noelia eWeisstaub; Martín eCammarota; Jorge Horacio Medina

    2014-01-01

    Medial prefrontal cortex (mPFC) is essential for initial memory processing and expression but its involvement in persistent memory storage has seldom been studied. Using the hippocampus dependent inhibitory avoidance learning task and the hippocampus-independent conditioned taste aversion paradigm together with specific dopamine receptor agonists and antagonists we found that persistence but not formation of long-term aversive memories requires dopamine D1/D5 receptors activation in mPFC imme...

  16. Will Dyscalculics Be Benefitted by Dint of Visual Learning?

    Science.gov (United States)

    Kumar, S. Praveen; Raja, B. William Dharma

    2009-01-01

    Not all children are made the same. Learning disabilities like dyslexia, dysgraphia or dyscalculia are either not understood or ignored in schools. As a result, the schoolchildren suffer for no fault of theirs and they lag behind in their course of learning. They may find it difficult to achieve the basic skills of learning such as reading,…

  17. GreedEx: A Visualization Tool for Experimentation and Discovery Learning of Greedy Algorithms

    Science.gov (United States)

    Velazquez-Iturbide, J. A.; Debdi, O.; Esteban-Sanchez, N.; Pizarro, C.

    2013-01-01

    Several years ago we presented an experimental, discovery-learning approach to the active learning of greedy algorithms. This paper presents GreedEx, a visualization tool developed to support this didactic method. The paper states the design goals of GreedEx, makes explicit the major design decisions adopted, and describes its main characteristics…

  18. Density of Visual Input Enhancement and Grammar Learning: A Research Proposal

    Science.gov (United States)

    Tran, Thu Hoang

    2009-01-01

    Research in the field of second language acquisition (SLA) has been done to ascertain the effectiveness of visual input enhancement (VIE) on grammar learning. However, one issue remains unexplored: the effects of VIE density on grammar learning. This paper presents a research proposal to investigate the effects of the density of VIE on English…

  19. Blended Learning in the Visual Communications Classroom: Student Reflections on a Multimedia Course

    Science.gov (United States)

    George-Palilonis, Jennifer; Filak, Vincent

    2009-01-01

    Advances in digital technology and a rapidly evolving media landscape continue to dramatically change teaching and learning. Among these changes is the emergence of multimedia teaching and learning tools, online degree programs, and hybrid classes that blend traditional and digital content delivery. At the same time, visual communication programs…

  20. Reliability and Validity of the Rey Visual Design Learning Test in Primary School Children

    NARCIS (Netherlands)

    Wilhelm, P.

    2004-01-01

    The Rey Visual Design Learning Test (Rey, 1964, in Spreen & Strauss, 1991) assesses immediate memory span, new learning and recognition for non-verbal material. Three studies are presented that focused on the reliability and validity of the RVDLT in primary school children. Test-retest reliability a

  1. Visual Learning: A Learner Centered Approach to Enhance English Language Teaching

    Science.gov (United States)

    Philominraj, Andrew; Jeyabalan, David; Vidal-Silva, Christian

    2017-01-01

    This article presents an empirical study carried out among the students of higher secondary schools to find out how English language learning occurs naturally in an environment where learners are encouraged by an appropriate method such as visual learning. The primary data was collected from 504 students with different pretested questionnaires. A…

  2. Web-Based Interactive 3D Visualization as a Tool for Improved Anatomy Learning

    Science.gov (United States)

    Petersson, Helge; Sinkvist, David; Wang, Chunliang; Smedby, Orjan

    2009-01-01

    Despite a long tradition, conventional anatomy education based on dissection is declining. This study tested a new virtual reality (VR) technique for anatomy learning based on virtual contrast injection. The aim was to assess whether students value this new three-dimensional (3D) visualization method as a learning tool and what value they gain…

  3. Dissociable Learning Processes Underlie Human Pain Conditioning.

    Science.gov (United States)

    Zhang, Suyi; Mano, Hiroaki; Ganesh, Gowrishankar; Robbins, Trevor; Seymour, Ben

    2016-01-11

    Pavlovian conditioning underlies many aspects of pain behavior, including fear and threat detection [1], escape and avoidance learning [2], and endogenous analgesia [3]. Although a central role for the amygdala is well established [4], both human and animal studies implicate other brain regions in learning, notably ventral striatum and cerebellum [5]. It remains unclear whether these regions make different contributions to a single aversive learning process or represent independent learning mechanisms that interact to generate the expression of pain-related behavior. We designed a human parallel aversive conditioning paradigm in which different Pavlovian visual cues probabilistically predicted thermal pain primarily to either the left or right arm and studied the acquisition of conditioned Pavlovian responses using combined physiological recordings and fMRI. Using computational modeling based on reinforcement learning theory, we found that conditioning involves two distinct types of learning process. First, a non-specific "preparatory" system learns aversive facial expressions and autonomic responses such as skin conductance. The associated learning signals-the learned associability and prediction error-were correlated with fMRI brain responses in amygdala-striatal regions, corresponding to the classic aversive (fear) learning circuit. Second, a specific lateralized system learns "consummatory" limb-withdrawal responses, detectable with electromyography of the arm to which pain is predicted. Its related learned associability was correlated with responses in ipsilateral cerebellar cortex, suggesting a novel computational role for the cerebellum in pain. In conclusion, our results show that the overall phenotype of conditioned pain behavior depends on two dissociable reinforcement learning circuits.

  4. An Interactive Approach to Learning and Teaching in Visual Arts Education

    Directory of Open Access Journals (Sweden)

    Zlata Tomljenović

    2015-09-01

    Full Text Available The present research focuses on modernising the approach to learning and teaching the visual arts in teaching practice, as well as examining the performance of an interactive approach to learning and teaching in visual arts classes with the use of a combination of general and specific (visual arts teaching methods. The study uses quantitative analysis of data on the basis of results obtained from a pedagogical experiment. The subjects of the research were 285 second- and fourth-grade students from four primary schools in the city of Rijeka, Croatia. Paintings made by the students in the initial and final stage of the pedagogical experiment were evaluated. The research results confirmed the hypotheses about the positive effect of interactive approaches to learning and teaching on the following variables: (1 knowledge and understanding of visual arts terms, (2 abilities and skills in the use of art materials and techniques within the framework of planned painting tasks, and (3 creativity in solving visual arts problems. The research results can help shape an optimised model for the planning and performance of visual arts education, and provide guidelines for planning professional development and the further professional education of teachers, with the aim of establishing more efficient learning and teaching of the visual arts in primary school.

  5. Blended learning promoting new developments for Nordic master programs in visual studies and art education

    DEFF Research Database (Denmark)

    Buhl, Mie; Ejsing-Duun, Stine

    2015-01-01

    This paper presents and discusses a blended course design in the international Nordic Visual Studies and Art Education (NoVA) master’s program developed and conducted by four Nordic partners. We examine a particular course - Visual cultures and aesthetics in digital communication and learning...... (Ejsing-Duun & Buhl forthcoming). The blended learning course VCAD involved a combination of face-to-face teaching with usage of location-based and mobile activities involving i-nigma, Instagram, and Pinterest, which comprised their learning materials and platforms. Furthermore, the course included online......-activities subordinate to the particular objectives of a specific discipline....

  6. Using Gephi to visualize online course participation: a Social Learning Analytics approach

    Directory of Open Access Journals (Sweden)

    Ángel Hernández-García

    2014-12-01

    Social learning analytics provides tools and methods for extracting information that is useful for improving the learning process. This case study shows how instructors and course coordinators can use the tool Gephi to generate relevant information that would otherwise be difficult to gain. Analysis of empirical data from a cross-curricular course with 656 students proves the usefulness of Gephi for social learning analytics studies and demonstrates how the tool can provide relevant indicators of student activity and engagement. The study also discusses the potential of social learning analytics for improving online instruction via learning data visualization.

  7. Phenylthiocarbamide produces conditioned taste aversions in mice.

    Science.gov (United States)

    St John, Steven J; Pour, Lindsay; Boughter, John D

    2005-06-01

    Previous work has demonstrated that SWR/J (SW) mice avoid phenylthiocarbamide (PTC) to a greater degree than C3HeB/FeJ mice in 48 h, two-bottle preference tests given in ascending series. The authors hypothesized, based also on previous work, that SW mice might form a conditioned taste aversion over time due to the toxic properties of PTC. We directly tested this hypothesis by attempting to condition a taste aversion to sucrose by injections of PTC. In experiment 1, PTC was nearly as effective as a strong dose of LiCl in reducing sucrose drinking. In experiment 2, the sucrose aversions were parametrically modified by both sucrose concentration and PTC dose, a hallmark of conditioned taste aversion. We conclude that PTC can cause a conditioned taste aversion and discuss the importance of considering toxic effects of aversive tastants when analyzing behavioral strain differences.

  8. Isolating Visual and Proprioceptive Components of Motor Sequence Learning in ASD.

    Science.gov (United States)

    Sharer, Elizabeth A; Mostofsky, Stewart H; Pascual-Leone, Alvaro; Oberman, Lindsay M

    2016-05-01

    In addition to defining impairments in social communication skills, individuals with autism spectrum disorder (ASD) also show impairments in more basic sensory and motor skills. Development of new skills involves integrating information from multiple sensory modalities. This input is then used to form internal models of action that can be accessed when both performing skilled movements, as well as understanding those actions performed by others. Learning skilled gestures is particularly reliant on integration of visual and proprioceptive input. We used a modified serial reaction time task (SRTT) to decompose proprioceptive and visual components and examine whether patterns of implicit motor skill learning differ in ASD participants as compared with healthy controls. While both groups learned the implicit motor sequence during training, healthy controls showed robust generalization whereas ASD participants demonstrated little generalization when visual input was constant. In contrast, no group differences in generalization were observed when proprioceptive input was constant, with both groups showing limited degrees of generalization. The findings suggest, when learning a motor sequence, individuals with ASD tend to rely less on visual feedback than do healthy controls. Visuomotor representations are considered to underlie imitative learning and action understanding and are thereby crucial to social skill and cognitive development. Thus, anomalous patterns of implicit motor learning, with a tendency to discount visual feedback, may be an important contributor in core social communication deficits that characterize ASD. Autism Res 2016, 9: 563-569. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

  9. Motivation versus aversive processing during perception.

    Science.gov (United States)

    Padmala, Srikanth; Pessoa, Luiz

    2014-06-01

    Reward facilitates performance and boosts cognitive performance across many tasks. At the same time, negative affective stimuli interfere with performance when they are not relevant to the task at hand. Yet, the investigation of how reward and negative stimuli impact perception and cognition has taken place in a manner that is largely independent of each other. How reward and negative emotion simultaneously contribute to behavioral performance is currently poorly understood. The aim of the present study was to investigate how the simultaneous manipulation of positive motivational processing (here manipulated via reward) and aversive processing (here manipulated via negative picture viewing) influence behavior during a perceptual task. We tested 2 competing hypotheses about the impact of reward on negative picture viewing. On the one hand, suggestions about the automaticity of emotional processing predict that negative picture interference would be relatively immune to reward. On the other, if affective visual processing is not obligatory, as we have argued in the past, reward may counteract the deleterious effect of more potent negative pictures. We found that reward counteracted the effect of potent, negative distracters during a visual discrimination task. Thus, when sufficiently motivated, participants were able to reduce the deleterious impact of bodily mutilation stimuli.

  10. Comparison of dependent measures used to quantify radiation-induced taste aversion

    Energy Technology Data Exchange (ETDEWEB)

    Spector, A.C.; Smith, J.C.; Hollander, G.R. (Florida State Univ., Tallahassee (USA). Dept. of Psychology)

    1981-11-01

    Several commonly used measures of conditioned taste aversion were compared under a variety of experimental conditions. In the first experiment an aversion to a saccharin solution (0.1%) was conditioned by pairing this taste substance with a single 100 R exposure to Cobalt-60. Comparisons were performed between the following measures: a short-term single-bottle test, a 22-hour two-bottle preference test, a measure quantifying recovery from the aversion along with other measures derived from these tests. Appropriate control groups received saccharin and sham exposure, water and sham exposure, and water and radiation exposure in order to measure both neophobia and enhanced neophobia. In Experiment 2 the total whole body radiation exposure used to condition the taste aversion was varied in different groups from 50 to 300 R exposures and the effect on conditioning was measured using the dependent variables described in Experiment 1. In Experiment 3 radiation-induced taste aversion was studied in rats which had prior exposures to the saccharin solution. In all three studies it was shown that different interpretations result from measuring the conditioned aversion with the different dependent variables commonly used, and several measures are needed to give a fair and accurate description of learned taste aversion.

  11. Ambiguity Aversion and the Criminal Process

    OpenAIRE

    Uzi Segal; Alex Stein

    2005-01-01

    This is the first article to examine the effects of ambiguity aversion on the criminal process. Ambiguity aversion is a person’s rational attitude towards probability's indeterminacy. When a person is averse towards such ambiguities, he increases the probability of the unfavorable outcome to reflect that fear. This observation is particularly true about a criminal defendant who faces a jury trial. Neither the defendant nor the prosecution knows whether the jury will convict the defendant. The...

  12. Mirror reversal and visual rotation are learned and consolidated via separate mechanisms: recalibrating or learning de novo?

    Science.gov (United States)

    Telgen, Sebastian; Parvin, Darius; Diedrichsen, Jörn

    2014-10-01

    Motor learning tasks are often classified into adaptation tasks, which involve the recalibration of an existing control policy (the mapping that determines both feedforward and feedback commands), and skill-learning tasks, requiring the acquisition of new control policies. We show here that this distinction also applies to two different visuomotor transformations during reaching in humans: Mirror-reversal (left-right reversal over a mid-sagittal axis) of visual feedback versus rotation of visual feedback around the movement origin. During mirror-reversal learning, correct movement initiation (feedforward commands) and online corrections (feedback responses) were only generated at longer latencies. The earliest responses were directed into a nonmirrored direction, even after two training sessions. In contrast, for visual rotation learning, no dependency of directional error on reaction time emerged, and fast feedback responses to visual displacements of the cursor were immediately adapted. These results suggest that the motor system acquires a new control policy for mirror reversal, which initially requires extra processing time, while it recalibrates an existing control policy for visual rotations, exploiting established fast computational processes. Importantly, memory for visual rotation decayed between sessions, whereas memory for mirror reversals showed offline gains, leading to better performance at the beginning of the second session than in the end of the first. With shifts in time-accuracy tradeoff and offline gains, mirror-reversal learning shares common features with other skill-learning tasks. We suggest that different neuronal mechanisms underlie the recalibration of an existing versus acquisition of a new control policy and that offline gains between sessions are a characteristic of latter.

  13. Inequality Aversion and Reciprocity in Moonlighting Games

    Directory of Open Access Journals (Sweden)

    Dirk Engelmann

    2010-10-01

    Full Text Available We study behavior in a moonlighting game with unequal initial endowments. In this game, predictions for second-mover behavior based on inequality aversion are in contrast to reciprocity. We find that inequality aversion explains only few observations. The comparison to a treatment with equal endowments supports the conclusion that behavior is better captured by intuitive notions of reciprocity than by inequality aversion. Extending the model by allowing for alternative reference points promises better performance, but leads to other problems. We conclude that the fact that inequality aversion often works as a good short-hand for reciprocity is driven by biased design choices.

  14. THE ROLE OF VISUAL VOCABULARY IN THE PROCESS OF LEARNING ITALIAN FOR SPECIFIC PURPOSE

    Directory of Open Access Journals (Sweden)

    Mirella Pederzoli

    2015-03-01

    Full Text Available The use of visual material does not imply necessarily the comprehension of the message included in it. It is necessary to go deeper, identifying the meaning enclosed into an expression using a visual code. In a formative context this aspect is even more relevant because the usage of visual material is growing due to also the new technologies applied to education. Therefore, this article highlights the main characteristics of a visual material for second languages acquisition, that is the visual vocabulary. First of all, the topic will be introduced through a semiotic overview about the usage of pictures in learning, underlining the process through which the meaning is spread across visual material. Indeed, the investigation of meaning-making includes the study of sign processes – that is semiosis – like analogy, metaphor, symbolism, likeness, etc., all aspects that characterize a linguistic code and a visual code too. Then, a literature review focuses on the main studies concerning the teaching and learning of vocabulary in a second language, especially in the field of the French lexicography. Finally, considering the characteristics of the visual material from a semiotic perspective, the final paragraph provides an example of a visual vocabulary of Italian as second language. This vocabulary is thought for foreign workers in the field of tourism and hosting that need to learn Italian for specific purpose. Thus, considering the proficiency level of that type of learners (A2, according to the CEFR and their limitation in terms of time spent for learning, the vocabulary represents an effective support material in the process of learning and retaining vocabulary and fixed expressions. Therefore, this article aims at contributing to the debate over the usage of visual material in the context of learning and teaching a second language, due to the fact that nowadays the society offers us a wide range of visual stimuli. Thus, as users or designers

  15. Neural systems underlying aversive conditioning in humans with primary and secondary reinforcers

    Directory of Open Access Journals (Sweden)

    Mauricio R Delgado

    2011-05-01

    Full Text Available Money is a secondary reinforcer commonly used across a range of disciplines in experimental paradigms investigating reward learning and decision-making. The effectiveness of monetary reinforcers during aversive learning and its neural basis, however, remains a topic of debate. Specifically, it is unclear if the initial acquisition of aversive representations of monetary losses depends on similar neural systems as more traditional aversive conditioning that involves primary reinforcers. This study contrasts the efficacy of a biologically defined primary reinforcer (shock and a socially defined secondary reinforcer (money during aversive learning and its associated neural circuitry. During a two-part experiment, participants first played a gambling game where wins and losses were based on performance to gain an experimental bank. Participants were then exposed to two separate aversive conditioning sessions. In one session, a primary reinforcer (mild shock served as an unconditioned stimulus (US and was paired with one of two colored squares, the conditioned stimuli (CS+ and CS-, respectively. In another session, a secondary reinforcer (loss of money served as the US and was paired with one of two different CS. Skin conductance responses were greater for CS+ compared to CS- trials irrespective of type of reinforcer. Neuroimaging results revealed that the striatum, a region typically linked with reward-related processing, was found to be involved in the acquisition of aversive conditioned response irrespective of reinforcer type. In contrast, the amygdala was involved during aversive conditioning with primary reinforcers, as suggested by both an exploratory fMRI analysis and a follow-up case study with a patient with bilateral amygdala damage. Taken together, these results suggest that learning about potential monetary losses may depend on reinforcement learning related systems, rather than on typical structures involved in more biologically based

  16. Changes in visual object recognition precede the shape bias in early noun learning

    Directory of Open Access Journals (Sweden)

    Meagan N Yee

    2012-12-01

    Full Text Available Two of the most formidable skills that characterize human beings are language and our prowess in visual object recognition. They may also be developmentally intertwined. Two experiments, a large sample cross-sectional study and a smaller sample 6-month longitudinal study of 18- 24 month olds tested a hypothesized developmental link between changes in the visual object representation and noun learning. Previous findings in visual object recognition indicate that children’s ability to recognize common basic level categories from sparse structural shape representations of object shape emerges between the ages of 18 and 24 months, is related to noun vocabulary size, and is lacking in children with language delay. Other research shows that in artificial noun learning tasks, during this same developmental period, young children systematically generalize object names by shape, that this shape bias predicts future noun learning, and is lacking in children with language delay. The two experiments examine the developmental relation between visual object recognition and the shape bias for the first time. The results show that developmental changes in visual object recognition systematically preceded the emergence of the shape bias. The results suggest a developmental pathway in which early changes in visual object recognition that are themselves linked to category learning enable the discovery of higher-order regularities in category structure and thus the shape bias in novel noun learning tasks. The proposed developmental pathway has implications for understanding the role of specific experience in the development of both visual object recognition and the shape bias in early noun learning.

  17. The effect of learning on the function of monkey extrastriate visual cortex.

    Directory of Open Access Journals (Sweden)

    Gregor Rainer

    2004-02-01

    Full Text Available One of the most remarkable capabilities of the adult brain is its ability to learn and continuously adapt to an ever-changing environment. While many studies have documented how learning improves the perception and identification of visual stimuli, relatively little is known about how it modifies the underlying neural mechanisms. We trained monkeys to identify natural images that were degraded by interpolation with visual noise. We found that learning led to an improvement in monkeys' ability to identify these indeterminate visual stimuli. We link this behavioral improvement to a learning-dependent increase in the amount of information communicated by V4 neurons. This increase was mediated by a specific enhancement in neural activity. Our results reveal a mechanism by which learning increases the amount of information that V4 neurons are able to extract from the visual environment. This suggests that V4 plays a key role in resolving indeterminate visual inputs by coordinated interaction between bottom-up and top-down processing streams.

  18. Online multi-modal robust non-negative dictionary learning for visual tracking.

    Science.gov (United States)

    Zhang, Xiang; Guan, Naiyang; Tao, Dacheng; Qiu, Xiaogang; Luo, Zhigang

    2015-01-01

    Dictionary learning is a method of acquiring a collection of atoms for subsequent signal representation. Due to its excellent representation ability, dictionary learning has been widely applied in multimedia and computer vision. However, conventional dictionary learning algorithms fail to deal with multi-modal datasets. In this paper, we propose an online multi-modal robust non-negative dictionary learning (OMRNDL) algorithm to overcome this deficiency. Notably, OMRNDL casts visual tracking as a dictionary learning problem under the particle filter framework and captures the intrinsic knowledge about the target from multiple visual modalities, e.g., pixel intensity and texture information. To this end, OMRNDL adaptively learns an individual dictionary, i.e., template, for each modality from available frames, and then represents new particles over all the learned dictionaries by minimizing the fitting loss of data based on M-estimation. The resultant representation coefficient can be viewed as the common semantic representation of particles across multiple modalities, and can be utilized to track the target. OMRNDL incrementally learns the dictionary and the coefficient of each particle by using multiplicative update rules to respectively guarantee their non-negativity constraints. Experimental results on a popular challenging video benchmark validate the effectiveness of OMRNDL for visual tracking in both quantity and quality.

  19. Online multi-modal robust non-negative dictionary learning for visual tracking.

    Directory of Open Access Journals (Sweden)

    Xiang Zhang

    Full Text Available Dictionary learning is a method of acquiring a collection of atoms for subsequent signal representation. Due to its excellent representation ability, dictionary learning has been widely applied in multimedia and computer vision. However, conventional dictionary learning algorithms fail to deal with multi-modal datasets. In this paper, we propose an online multi-modal robust non-negative dictionary learning (OMRNDL algorithm to overcome this deficiency. Notably, OMRNDL casts visual tracking as a dictionary learning problem under the particle filter framework and captures the intrinsic knowledge about the target from multiple visual modalities, e.g., pixel intensity and texture information. To this end, OMRNDL adaptively learns an individual dictionary, i.e., template, for each modality from available frames, and then represents new particles over all the learned dictionaries by minimizing the fitting loss of data based on M-estimation. The resultant representation coefficient can be viewed as the common semantic representation of particles across multiple modalities, and can be utilized to track the target. OMRNDL incrementally learns the dictionary and the coefficient of each particle by using multiplicative update rules to respectively guarantee their non-negativity constraints. Experimental results on a popular challenging video benchmark validate the effectiveness of OMRNDL for visual tracking in both quantity and quality.

  20. Adaptive learning in a compartmental model of visual cortex - how feedback enables stable category learning and refinement

    Directory of Open Access Journals (Sweden)

    Georg eLayher

    2014-12-01

    Full Text Available The categorization of real world objects is often reflected in the similarity of their visual appearances. Such categories of objects do not necessarily form disjunct sets of objects, neither semantically nor visually. The relationship between categories can often be described in terms of a hierarchical structure. For instance, tigers and leopards build two separate mammalian categories, but both belong to the category of felines. In other words, tigers and leopards are subcategories of the category Felidae. In the last decades, the unsupervised learning of categories of visual input stimuli has been addressed by numerous approaches in machine learning as well as in the computational neurosciences. However, the question of what kind of mechanisms might be involved in the process of subcategory learning, or category refinement, remains a topic of active investigation. We propose a recurrent computational network architecture for the unsupervised learning of categorial and subcategorial visual input representations. During learning, the connection strengths of bottom-up weights from input to higher-level category representations are adapted according to the input activity distribution. In a similar manner, top-down weights learn to encode the characteristics of a specific stimulus category. Feedforward and feedback learning in combination realize an associative memory mechanism, enabling the selective top-down propagation of a category's feedback weight distribution. We suggest that the difference between the expected input encoded in the projective field of a category node and the current input pattern controls the amplification of feedforward-driven representations. Large enough differences trigger the recruitment of new representational resources and the establishment of (sub- category representations. We demonstrate the temporal evolution of such learning and show how the approach successully establishes category and subcategory

  1. Medial prefrontal cortex dopamine controls the persistent storage of aversive memories

    Science.gov (United States)

    Gonzalez, María C.; Kramar, Cecilia P.; Tomaiuolo, Micol; Katche, Cynthia; Weisstaub, Noelia; Cammarota, Martín; Medina, Jorge H.

    2014-01-01

    Medial prefrontal cortex (mPFC) is essential for initial memory processing and expression but its involvement in persistent memory storage has seldom been studied. Using the hippocampus dependent inhibitory avoidance learning task and the hippocampus-independent conditioned taste aversion paradigm together with specific dopamine receptor agonists and antagonists we found that persistence but not formation of long-term aversive memories requires dopamine D1/D5 receptors activation in mPFC immediately after training and, depending on the task, between 6 and 12 h later. Our results indicate that besides its well-known participation in retrieval and early consolidation, mPFC also modulates the endurance of long-lasting aversive memories regardless of whether formation of the aversive mnemonic trace requires the participation of the hippocampus. PMID:25506318

  2. Medial prefrontal cortex dopamine controls the persistent storage of aversive memories

    Directory of Open Access Journals (Sweden)

    María Carolina Gonzalez

    2014-11-01

    Full Text Available Medial prefrontal cortex (mPFC is essential for initial memory processing and expression but its involvement in persistent memory storage has seldom been studied. Using the hippocampus dependent inhibitory avoidance learning task and the hippocampus-independent conditioned taste aversion paradigm together with specific dopamine receptor agonists and antagonists we found that persistence but not formation of long-tem aversive memories requires dopamine D1/D5 receptors activation in mPFC immediately after training and, depending on the task, between 6 and 12 hour later. Our results indicate that besides its well-known participation in retrieval and early consolidation, mPFC also modulates the endurance of long-lasting aversive memories regardless of whether formation of the aversive mnemonic trace requires the participation of the hippocampus.

  3. Lateral Habenula determines long-term storage of aversive memories

    Science.gov (United States)

    Tomaiuolo, Micol; Gonzalez, Carolina; Medina, Jorge H.; Piriz, Joaquin

    2014-01-01

    The Lateral Habenula (LHb) is a small brain structure that codifies negative motivational value and has been related to major depression. It has been shown recently that LHb activation is sufficient to induce aversive associative learning; however the key question about whether LHb activation is required for an aversive memory to be formed has not been addressed. In this article we studied the function of the LHb in memory formation using the Inhibitory Avoidance task (IA). We found that LHb inactivation during IA training does not disrupt memory when assessed 24 h after, but abolishes it 7 days later, indicating that LHb activity during memory acquisition is not necessary for memory formation, but regulates its temporal stability. These effects suggest that LHb inactivation modifies subjective perception of the training experience. PMID:24860453

  4. Lateral Habenula determines long-term storage of aversive memories.

    Directory of Open Access Journals (Sweden)

    Micol eTomaiuolo

    2014-05-01

    Full Text Available The Lateral Habenula (LHb is a small brain structure that codifies negative motivational value and has been related to major depression. It has been shown recently that LHb activation is sufficient to induce aversive associative learning; however the key question about whether LHb activation is required for an aversive memory to be formed has not been addressed. In this article we studied the function of the LHb in memory formation using the Inhibitory Avoidance task (IA. We found that LHb inactivation during IA training does not disrupt memory when assessed 24 hours after, but abolishes it 7 days later, indicating that LHb activity during memory acquisition is not necessary for memory formation, but regulates its temporal stability. These effects suggest that LHb inactivation modifies subjective perception of the training experience.

  5. Assessing learning preferences of dental students using visual, auditory, reading-writing, and kinesthetic questionnaire

    Directory of Open Access Journals (Sweden)

    Darshana Bennadi

    2015-01-01

    Full Text Available Introduction: Educators of the health care profession (teachers are committed in preparing future health care providers, but are facing many challenges in transmitting their ever expanding knowledge to the students. This study was done to focus on different learning styles among dental students. Aim: To assess different learning preferences among dental students. Materials and Methods: This is a descriptive cross-sectional questionnaire study using visual, auditory, reading-writing, and kinesthetic questionnaire among dental students. Results: Majority 75.8% of the students preferred multimodal learning style. Multimodal learning was common among clinical students. No statistical significant difference of learning styles in relation to gender (P > 0.05. Conclusion: In the present study, majority of students preferred multimodal learning preference. Knowledge about the learning style preference of different profession can help to enhance the teaching method for the students.

  6. Differential Endocannabinoid Regulation of Extinction in Appetitive and Aversive Barnes Maze Tasks

    Science.gov (United States)

    Harloe, John P.; Thorpe, Andrew J.; Lichtman, Aron H.

    2008-01-01

    CB[subscript 1] receptor-compromised animals show profound deficits in extinguishing learned behavior from aversive conditioning tasks, but display normal extinction learning in appetitive operant tasks. However, it is difficult to discern whether the differential involvement of the endogenous cannabinoid system on extinction results from the…

  7. New perspectives on e-learning for the blind and severely visually impaired

    Directory of Open Access Journals (Sweden)

    Linder, Roland

    2006-11-01

    Full Text Available In the late 90s different options has been established for media supported learning, so-called e-learning. The underlying mechanisms provide an appropriate platform for a novel learning environment that might help the blind and severely visually impaired. The options represent visual information provided by tactile analogies. A haptic device is used, i.e., a hardware device that helps present tactile information. The haptic device can generate a tactile representation of geometric objects and physical bodies. This can be provided with or without visual information and/or a teacher’s instructions. Respective requirements have been met by developing the prototypical software make2Dhaptic. In this paper applications of the haptic device and make2Dhaptic in combination with histological slides are discussed. The results of initial tests are promising.

  8. In Light of Visual Arts – A knowledge transfer partnership project as experiential learning

    Directory of Open Access Journals (Sweden)

    Ming-hoi Lai

    2013-10-01

    Full Text Available Knowledge transfer between universities and the commercial sector is becoming more prevalent, and different processes have been adopted to facilitate the transfer of knowledge. The ‘In Light of Visual Arts’ project aimed to facilitate knowledge exchange in relation to an innovative concept, the ‘eco-philosophy of light’, between the lighting industry and the arts and cultural sector through an Informal Learning approach. Young visual artists, light designers and lighting technicians were encouraged to explore and exchange experiences in the areas of visual communication, art appreciation and art archiving to create practical lighting solutions. This project offers a feasible framework for the enhancement of artistic training through knowledge sharing, for the benefit of the participants themselves and, in turn, academia, industry and the community. Keywords: informal learning, experiential learning, knowledge transfer, art education, interdisciplinary study

  9. Risk Aversion, Price Uncertainty and Irreversible Investments

    NARCIS (Netherlands)

    van den Goorbergh, R.W.J.; Huisman, K.J.M.; Kort, P.M.

    2003-01-01

    This paper generalizes the theory of irreversible investment under uncertainty by allowing for risk averse investors in the absence of com-plete markets.Until now this theory has only been developed in the cases of risk neutrality, or risk aversion in combination with complete markets.Within a gener

  10. Deep Cross Residual Learning for Multitask Visual Recognition

    OpenAIRE

    2016-01-01

    Residual learning has recently surfaced as an effective means of constructing very deep neural networks for object recognition. However, current incarnations of residual networks do not allow for the modeling and integration of complex relations between closely coupled recognition tasks or across domains. Such problems are often encountered in multimedia applications involving large-scale content recognition. We propose a novel extension of residual learning for deep networks that enables int...

  11. Visual intelligence using neural-symbolic learning and reasoning

    NARCIS (Netherlands)

    Penning, H.L.H. de

    2011-01-01

    The DARPA Mind’s Eye program seeks to develop in machines a capability that currently exists only in animals: visual intelligence. This short paper describes the initial results of a Neural-Symbolic approach for action recognition and description to be demonstrated at the 7th international workshop

  12. Enhancing the Teaching and Learning of Mathematical Visual Images

    Science.gov (United States)

    Quinnell, Lorna

    2014-01-01

    The importance of mathematical visual images is indicated by the introductory paragraph in the Statistics and Probability content strand of the Australian Curriculum, which draws attention to the importance of learners developing skills to analyse and draw inferences from data and "represent, summarise and interpret data and undertake…

  13. Posttraining transcranial magnetic stimulation of striate cortex disrupts consolidation early in visual skill learning.

    Science.gov (United States)

    De Weerd, Peter; Reithler, Joel; van de Ven, Vincent; Been, Marin; Jacobs, Christianne; Sack, Alexander T

    2012-02-01

    Practice-induced improvements in skilled performance reflect "offline " consolidation processes extending beyond daily training sessions. According to visual learning theories, an early, fast learning phase driven by high-level areas is followed by a late, asymptotic learning phase driven by low-level, retinotopic areas when higher resolution is required. Thus, low-level areas would not contribute to learning and offline consolidation until late learning. Recent studies have challenged this notion, demonstrating modified responses to trained stimuli in primary visual cortex (V1) and offline activity after very limited training. However, the behavioral relevance of modified V1 activity for offline consolidation of visual skill memory in V1 after early training sessions remains unclear. Here, we used neuronavigated transcranial magnetic stimulation (TMS) directed to a trained retinotopic V1 location to test for behaviorally relevant consolidation in human low-level visual cortex. Applying TMS to the trained V1 location within 45 min of the first or second training session strongly interfered with learning, as measured by impaired performance the next day. The interference was conditional on task context and occurred only when training in the location targeted by TMS was followed by training in a second location before TMS. In this condition, high-level areas may become coupled to the second location and uncoupled from the previously trained low-level representation, thereby rendering consolidation vulnerable to interference. Our data show that, during the earliest phases of skill learning in the lowest-level visual areas, a behaviorally relevant form of consolidation exists of which the robustness is controlled by high-level, contextual factors.

  14. Visual Literacy Skills of Students in College-Level Biology: Learning Outcomes Following Digital or Hand-Drawing Activities

    Science.gov (United States)

    Bell, Justine C.

    2014-01-01

    To test the claim that digital learning tools enhance the acquisition of visual literacy in this generation of biology students, a learning intervention was carried out with 33 students enrolled in an introductory college biology course. This study compared learning outcomes following two types of learning tools: a traditional drawing activity, or…

  15. Gains following perceptual learning are closely linked to the initial visual acuity.

    Science.gov (United States)

    Yehezkel, Oren; Sterkin, Anna; Lev, Maria; Levi, Dennis M; Polat, Uri

    2016-04-28

    The goal of the present study was to evaluate the dependence of perceptual learning gains on initial visual acuity (VA), in a large sample of subjects with a wide range of VAs. A large sample of normally sighted and presbyopic subjects (N = 119; aged 40 to 63) with a wide range of uncorrected near visual acuities (VA, -0.12 to 0.8 LogMAR), underwent perceptual learning. Training consisted of detecting briefly presented Gabor stimuli under spatial and temporal masking conditions. Consistent with previous findings, perceptual learning induced a significant improvement in near VA and reading speed under conditions of limited exposure duration. Our results show that the improvements in VA and reading speed observed following perceptual learning are closely linked to the initial VA, with only a minor fraction of the observed improvement that may be attributed to the additional sessions performed by those with the worse VA.

  16. Implementing an Android Tool for Visually Impaired Students of E-Learning

    Directory of Open Access Journals (Sweden)

    Alana Da Silva Luna

    2016-04-01

    Full Text Available This article aims to describe the process of learning and development of an educational tool designed for mobile devices (smartphones with Android technology. In summary, the application was developed based on the virtual learning environment Moodle and aims to develop a learning environment that supports the visually impaired students of e-learning, allowing them to ask questions, discuss and share ideas through forums and use chat rooms in real time. The fundamental purpose of this application is to cooperate with scientific knowledge in the sense that this is a representation of technological advance on the accessibility tools in distance education mode and provide comfort, flexibility and accessibility for the visually impaired students, realizing that education should always be inclusive.

  17. Statistical learning of visual transitions in monkey inferotemporal cortex.

    Science.gov (United States)

    Meyer, Travis; Olson, Carl R

    2011-11-29

    One of the most fundamental functions of the brain is to predict upcoming events on the basis of the recent past. A closely related function is to signal when a prediction has been violated. The identity of the brain regions that mediate these functions is not known. We set out to determine whether they are implemented at the level of single neurons in the visual system. We gave monkeys prolonged exposure to pairs of images presented in fixed sequence so that each leading image became a strong predictor for the corresponding trailing image. We then monitored the responses of neurons in the inferotemporal cortex to image sequences that obeyed or violated the transitional rules imposed during training. Inferotemporal neurons exhibited a transitional surprise effect, responding much more strongly to unpredicted transitions than to predicted transitions. Thus, neurons even in the visual system make experience-based predictions and react when they fail.

  18. Learning arm/hand coordination with an altered visual input.

    Science.gov (United States)

    Iftime Nielsen, Simona Denisia; Dosen, Strahinja; Popović, Mirjana B; Popović, Dejan B

    2010-01-01

    The focus of this study was to test a novel tool for the analysis of motor coordination with an altered visual input. The altered visual input was created using special glasses that presented the view as recorded by a video camera placed at various positions around the subject. The camera was positioned at a frontal (F), lateral (L), or top (T) position with respect to the subject. We studied the differences between the arm-end (wrist) trajectories while grasping an object between altered vision (F, L, and T conditions) and normal vision (N) in ten subjects. The outcome measures from the analysis were the trajectory errors, the movement parameters, and the time of execution. We found substantial trajectory errors and an increased execution time at the baseline of the study. We also found that trajectory errors decreased in all conditions after three days of practice with the altered vision in the F condition only for 20 minutes per day, suggesting that recalibration of the visual systems occurred relatively quickly. These results indicate that this recalibration occurs via movement training in an altered condition. The results also suggest that recalibration is more difficult to achieve for altered vision in the F and L conditions compared to the T condition. This study has direct implications on the design of new rehabilitation systems.

  19. Perceptual learning of basic visual features remains task specific with Training-Plus-Exposure (TPE) training.

    Science.gov (United States)

    Cong, Lin-Juan; Wang, Ru-Jie; Yu, Cong; Zhang, Jun-Yun

    2016-01-01

    Visual perceptual learning is known to be specific to the trained retinal location, feature, and task. However, location and feature specificity can be eliminated by double-training or TPE training protocols, in which observers receive additional exposure to the transfer location or feature dimension via an irrelevant task besides the primary learning task Here we tested whether these new training protocols could even make learning transfer across different tasks involving discrimination of basic visual features (e.g., orientation and contrast). Observers practiced a near-threshold orientation (or contrast) discrimination task. Following a TPE training protocol, they also received exposure to the transfer task via performing suprathreshold contrast (or orientation) discrimination in alternating blocks of trials in the same sessions. The results showed no evidence for significant learning transfer to the untrained near-threshold contrast (or orientation) discrimination task after discounting the pretest effects and the suprathreshold practice effects. These results thus do not support a hypothetical task-independent component in perceptual learning of basic visual features. They also set the boundary of the new training protocols in their capability to enable learning transfer.

  20. Cholinergic enhancement augments magnitude and specificity of visual perceptual learning in healthy humans.

    Science.gov (United States)

    Rokem, Ariel; Silver, Michael A

    2010-10-12

    Learning through experience underlies the ability to adapt to novel tasks and unfamiliar environments. However, learning must be regulated so that relevant aspects of the environment are selectively encoded. Acetylcholine (ACh) has been suggested to regulate learning by enhancing the responses of sensory cortical neurons to behaviorally relevant stimuli. In this study, we increased synaptic levels of ACh in the brains of healthy human subjects with the cholinesterase inhibitor donepezil (trade name: Aricept) and measured the effects of this cholinergic enhancement on visual perceptual learning. Each subject completed two 5 day courses of training on a motion direction discrimination task, once while ingesting 5 mg of donepezil before every training session and once while placebo was administered. We found that cholinergic enhancement augmented perceptual learning for stimuli having the same direction of motion and visual field location used during training. In addition, perceptual learning with donepezil was more selective to the trained direction of motion and visual field location. These results, combined with previous studies demonstrating an increase in neuronal selectivity following cholinergic enhancement, suggest a possible mechanism by which ACh augments neural plasticity by directing activity to populations of neurons that encode behaviorally relevant stimulus features.

  1. Socio-cognitive profiles for visual learning in young and older adults

    Directory of Open Access Journals (Sweden)

    Julie eChristian

    2015-06-01

    Full Text Available It is common wisdom that practice makes perfect; but why do some adults learn better than others? Here, we investigate individuals’ cognitive and social profiles to test which variables account for variability in learning ability across the lifespan. In particular, we focused on visual learning using tasks that test the ability to inhibit distractors and select task-relevant features. We tested the ability of young and older adults to improve through training in the discrimination of visual global forms embedded in a cluttered background. Further, we used a battery of cognitive tasks and psycho-social measures to examine which of these variables predict training-induced improvement in perceptual tasks and may account for individual variability in learning ability. Using partial least squares regression modelling, we show that visual learning is influenced by cognitive (i.e. cognitive inhibition, attention and social (strategic and deep learning factors rather than an individual’s age alone. Further, our results show that independent of age, strong learners rely on cognitive factors such as attention, while weaker learners use more general cognitive strategies. Our findings suggest an important role for higher-cognitive circuits involving executive functions that contribute to our ability to improve in perceptual tasks after training across the lifespan.

  2. Health Security and Risk Aversion.

    Science.gov (United States)

    Herington, Jonathan

    2016-09-01

    Health security has become a popular way of justifying efforts to control catastrophic threats to public health. Unfortunately, there has been little analysis of the concept of health security, nor the relationship between health security and other potential aims of public health policy. In this paper I develop an account of health security as an aversion to risky policy options. I explore three reasons for thinking risk avoidance is a distinctly worthwhile aim of public health policy: (i) that security is intrinsically valuable, (ii) that it is necessary for social planning and (iii) that it is an appropriate response to decision-making in contexts of very limited information. Striking the right balance between securing and maximizing population health thus requires a substantive, and hitherto unrecognized, value judgment. Finally, I critically evaluate the current health security agenda in light of this new account of the concept and its relationship to the other aims of public health policy.

  3. Visualizing learner activities with a virtual learning environment

    DEFF Research Database (Denmark)

    Eskildsen, Søren; Rodil, Kasper; Rehm, Matthias

    2012-01-01

    This paper presents how to gain insights into children’s navigation of an interactive virtual learning environment and how that would benefit their educators. A prototype for logging user information as quantifiable data has been developed and deployed in an in-situ evaluation of the system...

  4. Perceptual Organization of Visual Structure Requires a Flexible Learning Mechanism

    Science.gov (United States)

    Aslin, Richard N.

    2011-01-01

    Bhatt and Quinn (2011) provide a compelling and comprehensive review of empirical evidence that supports the operation of principles of perceptual organization in young infants. They also have provided a comprehensive list of experiences that could serve to trigger the learning of at least some of these principles of perceptual organization, and…

  5. Limited Rank Matrix Learning, discriminative dimension reduction and visualization

    NARCIS (Netherlands)

    Bunte, Kerstin; Schneider, Petra; Hammer, Barbara; Schleif, Frank-Michael; Villmann, Thomas; Biehl, Michael

    2012-01-01

    We present an extension of the recently introduced Generalized Matrix Learning Vector Quantization algorithm. In the original scheme, adaptive square matrices of relevance factors parameterize a discriminative distance measure. We extend the scheme to matrices of limited rank corresponding to low-di

  6. Visualization of Processes in Self-Learning Systems

    NARCIS (Netherlands)

    Peters, Gabriele; Bunte, Kerstin; Strickert, Marc; Biehl, Michael; Villmann, Thomas

    2012-01-01

    One aspect of self-organizing systems is their desired ability to be self-learning, i.e., to be able to adapt dynamically to conditions in their environment. This quality is awkward especially if it comes to applications in security or safety-sensitive areas. Here a step towards more trustful system

  7. Visualization of Learning Scenarios with UML4LD

    Science.gov (United States)

    Laforcade, Pierre

    2007-01-01

    Present Educational Modelling Languages are used to formally specify abstract learning scenarios in a machine-interpretable format. Current tooling does not provide teachers/designers with some graphical facilities to help them in reusing existent scenarios. They need human-readable representations. This paper discusses the UML4LD experimental…

  8. Learning a New Selection Rule in Visual and Frontal Cortex

    NARCIS (Netherlands)

    van der Togt, Chris; Stănişor, Liviu; Pooresmaeili, Arezoo; Albantakis, Larissa; Deco, Gustavo; Roelfsema, Pieter R

    2016-01-01

    How do you make a decision if you do not know the rules of the game? Models of sensory decision-making suggest that choices are slow if evidence is weak, but they may only apply if the subject knows the task rules. Here, we asked how the learning of a new rule influences neuronal activity in the vis

  9. Robust visual tracking via multi-task sparse learning

    KAUST Repository

    Zhang, Tianzhu

    2012-06-01

    In this paper, we formulate object tracking in a particle filter framework as a multi-task sparse learning problem, which we denote as Multi-Task Tracking (MTT). Since we model particles as linear combinations of dictionary templates that are updated dynamically, learning the representation of each particle is considered a single task in MTT. By employing popular sparsity-inducing p, q mixed norms (p D; 1), we regularize the representation problem to enforce joint sparsity and learn the particle representations together. As compared to previous methods that handle particles independently, our results demonstrate that mining the interdependencies between particles improves tracking performance and overall computational complexity. Interestingly, we show that the popular L 1 tracker [15] is a special case of our MTT formulation (denoted as the L 11 tracker) when p q 1. The learning problem can be efficiently solved using an Accelerated Proximal Gradient (APG) method that yields a sequence of closed form updates. As such, MTT is computationally attractive. We test our proposed approach on challenging sequences involving heavy occlusion, drastic illumination changes, and large pose variations. Experimental results show that MTT methods consistently outperform state-of-the-art trackers. © 2012 IEEE.

  10. Learning Program for Enhancing Visual Literacy for Non-Design Students Using a CMS to Share Outcomes

    Science.gov (United States)

    Ariga, Taeko; Watanabe, Takashi; Otani, Toshio; Masuzawa, Toshimitsu

    2016-01-01

    This study proposes a basic learning program for enhancing visual literacy using an original Web content management system (Web CMS) to share students' outcomes in class as a blog post. It seeks to reinforce students' understanding and awareness of the design of visual content. The learning program described in this research focuses on to address…

  11. Comparison of Learning Disabled Children's Performance on Bender Visual-Motor Gestalt Test and Beery's Developmental Test of Visual Motor Integration.

    Science.gov (United States)

    Skeen, Judith A.; And Others

    1982-01-01

    A comparison was made of the performance of 30 learning-disabled students on the Bender Visual-Motor Gestalt Test and the Beery Developmental Test of Visual Motor Integration. A significant correlation of -.72 was obtained. No significant difference was found in estimations of age equivalents. (Author)

  12. Reconsideration of Serial Visual Reversal Learning in Octopus (Octopus vulgaris) from a Methodological Perspective

    Science.gov (United States)

    Bublitz, Alexander; Weinhold, Severine R.; Strobel, Sophia; Dehnhardt, Guido; Hanke, Frederike D.

    2017-01-01

    Octopuses (Octopus vulgaris) are generally considered to possess extraordinary cognitive abilities including the ability to successfully perform in a serial reversal learning task. During reversal learning, an animal is presented with a discrimination problem and after reaching a learning criterion, the signs of the stimuli are reversed: the former positive becomes the negative stimulus and vice versa. If an animal improves its performance over reversals, it is ascribed advanced cognitive abilities. Reversal learning has been tested in octopus in a number of studies. However, the experimental procedures adopted in these studies involved pre-training on the new positive stimulus after a reversal, strong negative reinforcement or might have enabled secondary cueing by the experimenter. These procedures could have all affected the outcome of reversal learning. Thus, in this study, serial visual reversal learning was revisited in octopus. We trained four common octopuses (O. vulgaris) to discriminate between 2-dimensional stimuli presented on a monitor in a simultaneous visual discrimination task and reversed the signs of the stimuli each time the animals reached the learning criterion of ≥80% in two consecutive sessions. The animals were trained using operant conditioning techniques including a secondary reinforcer, a rod that was pushed up and down the feeding tube, which signaled the correctness of a response and preceded the subsequent primary reinforcement of food. The experimental protocol did not involve negative reinforcement. One animal completed four reversals and showed progressive improvement, i.e., it decreased its errors to criterion the more reversals it experienced. This animal developed a generalized response strategy. In contrast, another animal completed only one reversal, whereas two animals did not learn to reverse during the first reversal. In conclusion, some octopus individuals can learn to reverse in a visual task demonstrating behavioral

  13. The voice of the visual : visual learning strategies for problem analysis, social dialogue and mediated participation

    NARCIS (Netherlands)

    Witteveen, L.M.

    2009-01-01

    The changing needs for innovative learning strategies in the life sciences results from the growing complexity of societal issues. Nowadays, complex societal issues are also called ‘wicked problems.’ Wicked problems are problems that do not have one single solution that is right or wrong, good or ba

  14. Reading speed in the peripheral visual field of older adults: Does it benefit from perceptual learning?

    Science.gov (United States)

    Yu, Deyue; Cheung, Sing-Hang; Legge, Gordon E; Chung, Susana T L

    2010-04-21

    Enhancing reading ability in peripheral vision is important for the rehabilitation of people with central-visual-field loss from age-related macular degeneration (AMD). Previous research has shown that perceptual learning, based on a trigram letter-recognition task, improved peripheral reading speed among normally-sighted young adults (Chung, Legge, & Cheung, 2004). Here we ask whether the same happens in older adults in an age range more typical of the onset of AMD. Eighteen normally-sighted subjects, aged 55-76years, were randomly assigned to training or control groups. Visual-span profiles (plots of letter-recognition accuracy as a function of horizontal letter position) and RSVP reading speeds were measured at 10 degrees above and below fixation during pre- and post-tests for all subjects. Training consisted of repeated measurements of visual-span profiles at 10 degrees below fixation, in four daily sessions. The control subjects did not receive any training. Perceptual learning enlarged the visual spans in both trained (lower) and untrained (upper) visual fields. Reading speed improved in the trained field by 60% when the trained print size was used. The training benefits for these older subjects were weaker than the training benefits for young adults found by Chung et al. Despite the weaker training benefits, perceptual learning remains a potential option for low-vision reading rehabilitation among older adults.

  15. Joint learning and weighting of visual vocabulary for bag-of-feature based tissue classification

    KAUST Repository

    Wang, Jim Jing-Yan

    2013-12-01

    Automated classification of tissue types of Region of Interest (ROI) in medical images has been an important application in Computer-Aided Diagnosis (CAD). Recently, bag-of-feature methods which treat each ROI as a set of local features have shown their power in this field. Two important issues of bag-of-feature strategy for tissue classification are investigated in this paper: the visual vocabulary learning and weighting, which are always considered independently in traditional methods by neglecting the inner relationship between the visual words and their weights. To overcome this problem, we develop a novel algorithm, Joint-ViVo, which learns the vocabulary and visual word weights jointly. A unified objective function based on large margin is defined for learning of both visual vocabulary and visual word weights, and optimized alternately in the iterative algorithm. We test our algorithm on three tissue classification tasks: classifying breast tissue density in mammograms, classifying lung tissue in High-Resolution Computed Tomography (HRCT) images, and identifying brain tissue type in Magnetic Resonance Imaging (MRI). The results show that Joint-ViVo outperforms the state-of-art methods on tissue classification problems. © 2013 Elsevier Ltd.

  16. Visual-Motor Learning Using Haptic Devices: How Best to Train Surgeons?

    Directory of Open Access Journals (Sweden)

    Oscar Giles

    2012-05-01

    Full Text Available Laparoscopic surgery has revolutionised medicine but requires surgeons to learn new visual-motor mappings. The optimal method for training surgeons is unknown. For instance, it may be easier to learn planar movements when training is constrained to a plane, since this forces the surgeon to develop an appropriate perceptual-motor map. In contrast, allowing the surgeon to move without constraints could improve performance because this provides greater experience of the control dynamics of the device. In order to test between these alternatives, we created an experimental tool that connected a commercially available robotic arm with specialised software that presents visual stimuli and objectively records kinematics. Participants were given the task of generating a series of aiming movements to move a visual cursor to a series of targets. The actions required movement along a horizontal plane, whereas the visual display was a screen positioned perpendicular to this plane (ie, vertically. One group (n=8 received training where the force field constrained their movement to the correct plane of action, whilst a second group (n=8 trained without constraints. On test trials (after training the unconstrained group showed better performance, as indexed by reduced movement duration and reduced path length. These results show that participants who explored the entire action space had an advantage, which highlights the importance of experiencing the full dynamics of a control device and the action space when learning a new visual-motor mapping.

  17. Social influences on inequity aversion in children.

    Directory of Open Access Journals (Sweden)

    Katherine McAuliffe

    Full Text Available Adults and children are willing to sacrifice personal gain to avoid both disadvantageous and advantageous inequity. These two forms of inequity aversion follow different developmental trajectories, with disadvantageous inequity aversion emerging around 4 years and advantageous inequity aversion emerging around 8 years. Although inequity aversion is assumed to be specific to situations where resources are distributed among individuals, the role of social context has not been tested in children. Here, we investigated the influence of two aspects of social context on inequity aversion in 4- to 9-year-old children: (1 the role of the experimenter distributing rewards and (2 the presence of a peer with whom rewards could be shared. Experiment 1 showed that children rejected inequity at the same rate, regardless of whether the experimenter had control over reward allocations. This indicates that children's decisions are based upon reward allocations between themselves and a peer and are not attempts to elicit more favorable distributions from the experimenter. Experiment 2 compared rejections of unequal reward allocations in children interacting with or without a peer partner. When faced with a disadvantageous distribution, children frequently rejected a smaller reward when a larger reward was visible, even if no partner would obtain the larger reward. This suggests that nonsocial factors partly explain disadvantageous inequity rejections. However, rejections of disadvantageous distributions were higher when the larger amount would go to a peer, indicating that social context enhances disadvantageous inequity aversion. By contrast, children rejected advantageous distributions almost exclusively in the social context. Therefore, advantageous inequity aversion appears to be genuinely social, highlighting its potential relevance for the development of fairness concerns. By comparing social and nonsocial factors, this study provides a detailed picture of

  18. The Challenges of Educating the Visually Impaired and Quality Assurance in Tertiary Institutions of Learning in Nigeria

    Science.gov (United States)

    Omede, Andrew A.

    2015-01-01

    This paper focused on the challenges in educating the visually impaired and modalities for ensuring quality assurance in tertiary institutions of learning in Nigeria. It examined the global challenges in the higher educational system and made it clear that the visually impaired are those with visual problems be it partial, low vision, or total…

  19. An Issue of Learning: The Effect of Visual Split Attention in Classes for Deaf and Hard of Hearing Students

    Science.gov (United States)

    Mather, Susan M.; Clark, M. Diane

    2012-01-01

    One of the ongoing challenges teachers of students who are deaf or hard of hearing face is managing the visual split attention implicit in multimedia learning. When a teacher presents various types of visual information at the same time, visual learners have no choice but to divide their attention among those materials and the teacher and…

  20. Learning from data: recognizing glaucomatous defect patterns and detecting progression from visual field measurements.

    Science.gov (United States)

    Yousefi, Siamak; Goldbaum, Michael H; Balasubramanian, Madhusudhanan; Medeiros, Felipe A; Zangwill, Linda M; Liebmann, Jeffrey M; Girkin, Christopher A; Weinreb, Robert N; Bowd, Christopher

    2014-07-01

    A hierarchical approach to learn from visual field data was adopted to identify glaucomatous visual field defect patterns and to detect glaucomatous progression. The analysis pipeline included three stages, namely, clustering, glaucoma boundary limit detection, and glaucoma progression detection testing. First, cross-sectional visual field tests collected from each subject were clustered using a mixture of Gaussians and model parameters were estimated using expectation maximization. The visual field clusters were further estimated to recognize glaucomatous visual field defect patterns by decomposing each cluster into several axes. The glaucoma visual field defect patterns along each axis then were identified. To derive a definition of progression, the longitudinal visual fields of stable glaucoma eyes on the abnormal cluster axes were projected and the slope was approximated using linear regression (LR) to determine the confidence limit of each axis. For glaucoma progression detection, the longitudinal visual fields of each eye on the abnormal cluster axes were projected and the slope was approximated by LR. Progression was assigned if the progression rate was greater than the boundary limit of the stable eyes; otherwise, stability was assumed. The proposed method was compared to a recently developed progression detection method and to clinically available glaucoma progression detection software. The clinical accuracy of the proposed pipeline was as good as or better than the currently available methods.

  1. Reading Authentic EFL Text Using Visualization and Advance Organizers in a Multimedia Learning Environment

    Science.gov (United States)

    Lin, Huifen; Chen, Tsuiping

    2007-01-01

    The purpose of this experimental study was to compare the effects of different types of computer-generated visuals (static versus animated) and advance organizers (descriptive versus question) in enhancing comprehension and retention of a content-based lesson for learning English as a Foreign Language (EFL). Additionally, the study investigated…

  2. Learning about Complex Multi-Stakeholder Issues: Assessing the Visual Problem Appraisal

    NARCIS (Netherlands)

    Witteveen, L.M.; Put, M.; Leeuwis, C.

    2010-01-01

    This paper presents an evaluation of the visual problem appraisal (VPA) learning environment in higher education. The VPA has been designed for the training of competences that are required in complex stakeholder settings in relation to sustainability issues. The design of VPA incorporates a diversi

  3. A Visual Approach to Helping Instructors Integrate, Document, and Refine Active Learning

    Science.gov (United States)

    Frey, Regina F.; Fisher, Beth A.; Solomon, Erin D.; Leonard, Denise A.; Mutambuki, Jacinta M.; Cohen, Cheryl A.; Luo, Jia; Pondugula, Santhi

    2016-01-01

    This article describes a visual approach to integrating observational data into self-evaluation and peer review of teaching, practices that can lead to adoption of evidence-based active-learning strategies in STEM. This approach was designed to be implemented for undergraduate courses across disciplines. The presentation of observational data in a…

  4. Project LMA: Learning Media Assessment of Students with Visual Impairments. Facilitator's Manual and Participant Workbook.

    Science.gov (United States)

    Koenig, Alan J.; Holbrook, M. Cay

    This document is comprised of the facilitator's manual and the participant's workbook for a 1- or 2-day workshop for inservice and preservice teachers on the process of learning media assessment (LMA) for students with visual impairments. The manual and workbook are intended for use in a complete program that also includes videotapes and…

  5. Meeting the Needs of Students with Coexisting Visual Impairments and Learning Disabilities

    Science.gov (United States)

    Jones, Beth A.; Hensley-Maloney, Lauren

    2015-01-01

    The coexistence of visual impairments and learning disabilities presents unique challenges. It is imperative that teachers be apprised of the characteristics of this population as well as instructional strategies targeted at meeting their unique needs. The authors highlight typical patterns of performance and provide suggestions for effective…

  6. Learning Visual Forward Models to Compensate for Self-Induced Image Motion.

    NARCIS (Netherlands)

    Ghadirzadeh, A.; Kootstra, G.W.; Maki, A.; Björkman, M.

    2014-01-01

    Predicting the sensory consequences of an agent's own actions is considered an important skill for intelligent behavior. In terms of vision, so-called visual forward models can be applied to learn such predictions. This is no trivial task given the high-dimensionality of sensory data and complex act

  7. Q Workshop: An Application of Q Methodology for Visualizing, Deliberating and Learning Contrasting Perspectives

    Science.gov (United States)

    Yoshizawa, Go; Iwase, Mineyo; Okumoto, Motoko; Tahara, Keiichiro; Takahashi, Shingo

    2016-01-01

    A value-centered approach to science, technology and society (STS) education illuminates the need of reflexive and relational learning through communication and public engagement. Visualization is a key to represent and compare mental models such as assumptions, background theories and value systems that tacitly shape our own understanding,…

  8. The Role of Visual Speech Information in Supporting Perceptual Learning of Degraded Speech

    Science.gov (United States)

    Wayne, Rachel V.; Johnsrude, Ingrid S.

    2012-01-01

    Following cochlear implantation, hearing-impaired listeners must adapt to speech as heard through their prosthesis. Visual speech information (VSI; the lip and facial movements of speech) is typically available in everyday conversation. Here, we investigate whether learning to understand a popular auditory simulation of speech as transduced by a…

  9. Enhancement of Online Robotics Learning Using Real-Time 3D Visualization Technology

    Directory of Open Access Journals (Sweden)

    Richard Chiou

    2010-06-01

    Full Text Available This paper discusses a real-time e-Lab Learning system based on the integration of 3D visualization technology with a remote robotic laboratory. With the emergence and development of the Internet field, online learning is proving to play a significant role in the upcoming era. In an effort to enhance Internet-based learning of robotics and keep up with the rapid progression of technology, a 3- Dimensional scheme of viewing the robotic laboratory has been introduced in addition to the remote controlling of the robots. The uniqueness of the project lies in making this process Internet-based, and remote robot operated and visualized in 3D. This 3D system approach provides the students with a more realistic feel of the 3D robotic laboratory even though they are working remotely. As a result, the 3D visualization technology has been tested as part of a laboratory in the MET 205 Robotics and Mechatronics class and has received positive feedback by most of the students. This type of research has introduced a new level of realism and visual communications to online laboratory learning in a remote classroom.

  10. Multivariate Gradient Analysis for Evaluating and Visualizing a Learning System Platform for Computer Programming

    Science.gov (United States)

    Mather, Richard

    2015-01-01

    This paper explores the application of canonical gradient analysis to evaluate and visualize student performance and acceptance of a learning system platform. The subject of evaluation is a first year BSc module for computer programming. This uses "Ceebot," an animated and immersive game-like development environment. Multivariate…

  11. Spatial Visualization as Mediating between Mathematics Learning Strategy and Mathematics Achievement among 8th Grade Students

    Science.gov (United States)

    Rabab'h, Belal; Veloo, Arsaythamby

    2015-01-01

    Jordanian 8th grade students revealed low achievement in mathematics through four periods (1999, 2003, 2007 & 2011) of Trends in International Mathematics and Science Study (TIMSS). This study aimed to determine whether spatial visualization mediates the affect of Mathematics Learning Strategies (MLS) factors namely mathematics attitude,…

  12. Visual Input Enhancement and Grammar Learning: A Meta-Analytic Review

    Science.gov (United States)

    Lee, Sang-Ki; Huang, Hung-Tzu

    2008-01-01

    Effects of pedagogical interventions with visual input enhancement on grammar learning have been investigated by a number of researchers during the past decade and a half. The present review delineates this research domain via a systematic synthesis of 16 primary studies (comprising 20 unique study samples) retrieved through an exhaustive…

  13. The Relationship between Visual Metaphor Comprehension and Recognition of Similarities in Children with Learning Disabilities

    Science.gov (United States)

    Mashal, Nira; Kasirer, Anat

    2012-01-01

    Previous studies have shown metaphoric comprehension deficits in children with learning disabilities. To understand metaphoric language, children must have enough semantic knowledge about the metaphorical terms and the ability to recognize similarity between two different domains. In the current study visual and verbal metaphor understanding was…

  14. The Effect of Learning Background and Imagery Cognitive Development on Visual Perception

    Science.gov (United States)

    Chiang, Shyh-Bao; Sun, Chun-Wang

    2013-01-01

    This research looked into the effect of how cognitive development toward imagery is formed through visual perception by means of a quantitative questionnaire. The main variable was the difference between the learning backgrounds of the interviewees. A two-way ANOVA mixed design was the statistical method used for the analysis of the 2 × 4 (2 by 4)…

  15. Building a Learning Readiness Program for the Mainstreamed Visually Impaired Child in Israel.

    Science.gov (United States)

    Wohl, Aryeh; Eshet, Shari

    1985-01-01

    The paper describes the beginnings of a total developmental language learning system for mainstreamed visually impaired children in Israel. The readiness program is divided into five sections: auditory perception and discrimination, tactile perception and discrimination and fine motor coordination, gross motor coordination, body image awareness,…

  16. Real-Time Data Display, Spatial Visualization Ability, and Learning Force and Motion Concepts

    Science.gov (United States)

    Kozhevnikov, Maria; Thornton, Ronald

    2006-01-01

    In this study, we examined how students' levels of spatial visualization ability interact with learning physics in a microcomputer-based laboratory (MBL) environment. Undergraduate students who had taken an introductory physics course based on MBL tools were pre- and posttested at the beginning and at the end of the semester on spatial…

  17. Visualization of agreement and discussion processes during computer-supported collaborative learning

    NARCIS (Netherlands)

    Janssen, J.J.H.M.; Erkens, G.; Kanselaar, G.

    2007-01-01

    This study examined the effects of the shared space (SS) on students’ behaviors in a computer-supported collaborative learning (CSCL) environment. The SS visualizes discussion and agreement during online discussions. It was hypothesized the SS would increase the media richness of the CSCL-environmen

  18. Music Learning through All the Channels: Combining Aural, Visual, and Kinesthetic Strategies to Develop Musical Understanding

    Science.gov (United States)

    Gault, Brent

    2005-01-01

    The article discusses music learning through aural, visual and kinesthetic strategies. Most general music teachers are aware of the contributions made to the profession by proponents of the Dalcroze, Kodaly, and Orff approaches to music instruction. It was claimed that students used one of the said strategies as their most efficient way to process…

  19. The ruler of inclusion in the process of people learning with visual disability.

    Science.gov (United States)

    Mafra, Eliane; Batiz, Eduardo Concepcion; Macedo, Marcelo

    2012-01-01

    The aim of this project is the development of a pedagogical tool that could address the needs related to the learning process of the blind and could also be used in the pedagogical process of people who are visually impaired. This project also has the objective of showing how the forms of the Ruler of Inclusion were planned in order to facilitate learning while addressing issues related to its safety, practicality and multifunctionality, aspects that are broached in a future work using descriptive, exploratory and phenomenological analyses to verify the understanding of the learning concepts applied to the ruler.

  20. Visual technology for the autonomous learning of mathematics

    Directory of Open Access Journals (Sweden)

    Helmut Linneweber‐Lammerskitten

    2010-07-01

    Full Text Available This paper describes a collaborative research and development project between the University of Applied Sciences Northwestern Switzerland and Rhodes University in South Africa. The project seeks to establish, disseminate and research the efficacy and use of short video clips designed specifically for the autonomous learning of mathematics. Specific to the South African context is our interest in capitalising on the ubiquity of cellphone technology and the autonomous affordances offered by mobile learning. This paper engages with a number of theoretical and pedagogical issues relating to the design, production and use of these video clips. Although the focus is specific to the contexts of South Africa and Switzerland, the discussion is of broad applicability.

  1. Visual feedback for a student learning language pronunciation

    OpenAIRE

    Fritzsche, Kenneth H

    1997-01-01

    Approved for public release; distribution is unlimited The learning of language pronunciation can be a frustrating and time consuming process. Traditional methods require feedback from another person, usually an instructor or another student, or use of a self assessment technique such as the listen record and compare technique. These techniques have flaws. Human factors such as self confidence, shyness, fatigue, hearing ability, vocal tract agility, and confidence in the instructors fairne...

  2. Robust visual tracking via structured multi-task sparse learning

    KAUST Repository

    Zhang, Tianzhu

    2012-11-09

    In this paper, we formulate object tracking in a particle filter framework as a structured multi-task sparse learning problem, which we denote as Structured Multi-Task Tracking (S-MTT). Since we model particles as linear combinations of dictionary templates that are updated dynamically, learning the representation of each particle is considered a single task in Multi-Task Tracking (MTT). By employing popular sparsity-inducing lp,q mixed norms (specifically p∈2,∞ and q=1), we regularize the representation problem to enforce joint sparsity and learn the particle representations together. As compared to previous methods that handle particles independently, our results demonstrate that mining the interdependencies between particles improves tracking performance and overall computational complexity. Interestingly, we show that the popular L1 tracker (Mei and Ling, IEEE Trans Pattern Anal Mach Intel 33(11):2259-2272, 2011) is a special case of our MTT formulation (denoted as the L11 tracker) when p=q=1. Under the MTT framework, some of the tasks (particle representations) are often more closely related and more likely to share common relevant covariates than other tasks. Therefore, we extend the MTT framework to take into account pairwise structural correlations between particles (e.g. spatial smoothness of representation) and denote the novel framework as S-MTT. The problem of learning the regularized sparse representation in MTT and S-MTT can be solved efficiently using an Accelerated Proximal Gradient (APG) method that yields a sequence of closed form updates. As such, S-MTT and MTT are computationally attractive. We test our proposed approach on challenging sequences involving heavy occlusion, drastic illumination changes, and large pose variations. Experimental results show that S-MTT is much better than MTT, and both methods consistently outperform state-of-the-art trackers. © 2012 Springer Science+Business Media New York.

  3. Risk Aversion Relates to Cognitive Ability

    DEFF Research Database (Denmark)

    Andersson, Ola; Holm, Håkan J.; Tyran, Jean-Robert Karl

    2016-01-01

    Recent experimental studies suggest that risk aversion is negatively related to cognitive ability. In this paper we report evidence that this relation might be spurious. We recruit a large subject pool drawn from the general Danish population for our experiment. By presenting subjects with choice...... tasks that vary the bias induced by random choices, we are able to generate both negative and positive correlations between risk aversion and cognitive ability. Structural estimation allowing for heterogeneity of noise yields no significant relation between risk aversion and cognitive ability. Our...... results suggest that cognitive ability is related to random decision making, rather than to risk preferences....

  4. Risk aversion relates to cognitive ability

    DEFF Research Database (Denmark)

    Andersson, Ola; Holm, Håkan J.; Tyran, Jean-Robert Karl

    Recent experimental studies suggest that risk aversion is negatively related to cognitive ability. In this paper we report evidence that this relation might be spurious. We recruit a large subject pool drawn from the general Danish population for our experiment. By presenting subjects with choice...... tasks that vary the bias induced by random choices, we are able to generate both negative and positive correlations between risk aversion and cognitive ability. Structural estimation allowing for heterogeneity of noise yields no significant relation between risk aversion and cognitive ability. Our...... results suggest that cognitive ability is related to random decision making rather than to risk preferences....

  5. Low-rank sparse learning for robust visual tracking

    KAUST Repository

    Zhang, Tianzhu

    2012-01-01

    In this paper, we propose a new particle-filter based tracking algorithm that exploits the relationship between particles (candidate targets). By representing particles as sparse linear combinations of dictionary templates, this algorithm capitalizes on the inherent low-rank structure of particle representations that are learned jointly. As such, it casts the tracking problem as a low-rank matrix learning problem. This low-rank sparse tracker (LRST) has a number of attractive properties. (1) Since LRST adaptively updates dictionary templates, it can handle significant changes in appearance due to variations in illumination, pose, scale, etc. (2) The linear representation in LRST explicitly incorporates background templates in the dictionary and a sparse error term, which enables LRST to address the tracking drift problem and to be robust against occlusion respectively. (3) LRST is computationally attractive, since the low-rank learning problem can be efficiently solved as a sequence of closed form update operations, which yield a time complexity that is linear in the number of particles and the template size. We evaluate the performance of LRST by applying it to a set of challenging video sequences and comparing it to 6 popular tracking methods. Our experiments show that by representing particles jointly, LRST not only outperforms the state-of-the-art in tracking accuracy but also significantly improves the time complexity of methods that use a similar sparse linear representation model for particles [1]. © 2012 Springer-Verlag.

  6. Parts-based stereoscopic image assessment by learning binocular manifold color visual properties

    Science.gov (United States)

    Xu, Haiyong; Yu, Mei; Luo, Ting; Zhang, Yun; Jiang, Gangyi

    2016-11-01

    Existing stereoscopic image quality assessment (SIQA) methods are mostly based on the luminance information, in which color information is not sufficiently considered. Actually, color is part of the important factors that affect human visual perception, and nonnegative matrix factorization (NMF) and manifold learning are in line with human visual perception. We propose an SIQA method based on learning binocular manifold color visual properties. To be more specific, in the training phase, a feature detector is created based on NMF with manifold regularization by considering color information, which not only allows parts-based manifold representation of an image, but also manifests localized color visual properties. In the quality estimation phase, visually important regions are selected by considering different human visual attention, and feature vectors are extracted by using the feature detector. Then the feature similarity index is calculated and the parts-based manifold color feature energy (PMCFE) for each view is defined based on the color feature vectors. The final quality score is obtained by considering a binocular combination based on PMCFE. The experimental results on LIVE I and LIVE Π 3-D IQA databases demonstrate that the proposed method can achieve much higher consistency with subjective evaluations than the state-of-the-art SIQA methods.

  7. The Effect of Visual and Etymological Treatments on Learning Decomposable Idioms among EFL Learners

    Directory of Open Access Journals (Sweden)

    Nassim Golaghaei

    2015-09-01

    Full Text Available The present study endeavors to investigate the impact of visual and etymological treatments on learning idioms among English language learners. Seventy-nine intermediate students at Rooz Academy Language School in Babol were selected from among a total number of 116 learners based on their performances on the Longman complete course for the TOEFL test to fulfill the purpose of the study. The students were then assigned into three experimental groups. Initially, a pre-test of idiomatic expressions including 48 idiomatic items was administered to the participants in all groups. During the instructional period, the groups were taught a group of abnormally decomposable idioms through different treatments, namely, visual, etymological, and a combination of visual-etymological elaboration. At the end of the instructional period, the participants in all groups were given a posttest which was the same as the pretest. The design of this study is quasi-experimental. The data obtained was analyzed using one-way ANOVA analysis. The results of data analysis revealed that the etymological treatment was more effective than visual aids on learning idioms among intermediate English language learners. However, the visual-etymological treatment was the most effective one. The findings of this study have implications for EFL teachers, students, and materials developers. Keywords: Visualization, Etymology, Idiom, Dual coding theory

  8. Visual one-shot learning as an 'anti-camouflage device': a novel morphing paradigm.

    Science.gov (United States)

    Ishikawa, Tetsuo; Mogi, Ken

    2011-09-01

    Once people perceive what is in the hidden figure such as Dallenbach's cow and Dalmatian, they seldom seem to come back to the previous state when they were ignorant of the answer. This special type of learning process can be accomplished in a short time, with the effect of learning lasting for a long time (visual one-shot learning). Although it is an intriguing cognitive phenomenon, the lack of the control of difficulty of stimuli presented has been a problem in research. Here we propose a novel paradigm to create new hidden figures systematically by using a morphing technique. Through gradual changes from a blurred and binarized two-tone image to a blurred grayscale image of the original photograph including objects in a natural scene, spontaneous one-shot learning can occur at a certain stage of morphing when a sufficient amount of information is restored to the degraded image. A negative correlation between confidence levels and reaction times is observed, giving support to the fluency theory of one-shot learning. The correlation between confidence ratings and correct recognition rates indicates that participants had an accurate introspective ability (metacognition). The learning effect could be tested later by verifying whether or not the target object was recognized quicker in the second exposure. The present method opens a way for a systematic production of "good" hidden figures, which can be used to demystify the nature of visual one-shot learning.

  9. Pattern identification or 3D visualization? How best to learn topographic map comprehension

    Science.gov (United States)

    Atit, Kinnari

    Science, Technology, Engineering, and Mathematics (STEM) experts employ many representations that novices find hard to use because they require a critical STEM skill, interpreting two-dimensional (2D) diagrams that represent three-dimensional (3D) information. The current research focuses on learning to interpret topographic maps. Understanding topographic maps requires knowledge of how to interpret the conventions of contour lines, and skill in visualizing that information in 3D (e.g. shape of the terrain). Novices find both tasks difficult. The present study compared two interventions designed to facilitate understanding for topographic maps to minimal text-only instruction. The 3D Visualization group received instruction using 3D gestures and models to help visualize three topographic forms. The Pattern Identification group received instruction using pointing and tracing gestures to help identify the contour patterns associated with the three topographic forms. The Text-based Instruction group received only written instruction explaining topographic maps. All participants then completed a measure of topographic map use. The Pattern Identification group performed better on the map use measure than participants in the Text-based Instruction group, but no significant difference was found between the 3D Visualization group and the other two groups. These results suggest that learning to identify meaningful contour patterns is an effective strategy for learning how to comprehend topographic maps. Future research should address if learning strategies for how to interpret the information represented on a diagram (e.g. identify patterns in the contour lines), before trying to visualize the information in 3D (e.g. visualize the 3D structure of the terrain), also facilitates students' comprehension of other similar types of diagrams.

  10. Anatomical substrates of visual and auditory miniature second-language learning.

    Science.gov (United States)

    Newman-Norlund, Roger D; Frey, Scott H; Petitto, Laura-Ann; Grafton, Scott T

    2006-12-01

    Longitudinal changes in brain activity during second language (L2) acquisition of a miniature finite-state grammar, named Wernickese, were identified with functional magnetic resonance imaging (fMRI). Participants learned either a visual sign language form or an auditory-verbal form to equivalent proficiency levels. Brain activity during sentence comprehension while hearing/viewing stimuli was assessed at low, medium, and high levels of proficiency in three separate fMRI sessions. Activation in the left inferior frontal gyrus (Broca's area) correlated positively with improving L2 proficiency, whereas activity in the right-hemisphere (RH) homologue was negatively correlated for both auditory and visual forms of the language. Activity in sequence learning areas including the premotor cortex and putamen also correlated with L2 proficiency. Modality-specific differences in the blood oxygenation level-dependent signal accompanying L2 acquisition were localized to the planum temporale (PT). Participants learning the auditory form exhibited decreasing reliance on bilateral PT sites across sessions. In the visual form, bilateral PT sites increased in activity between Session 1 and Session 2, then decreased in left PT activity from Session 2 to Session 3. Comparison of L2 laterality (as compared to L1 laterality) in auditory and visual groups failed to demonstrate greater RH lateralization for the visual versus auditory L2. These data establish a common role for Broca's area in language acquisition irrespective of the perceptual form of the language and suggest that L2s are processed similar to first languages even when learned after the "critical period." The right frontal cortex was not preferentially recruited by visual language after accounting for phonetic/structural complexity and performance.

  11. Real-Time Strategy Video Game Experience and Visual Perceptual Learning.

    Science.gov (United States)

    Kim, Yong-Hwan; Kang, Dong-Wha; Kim, Dongho; Kim, Hye-Jin; Sasaki, Yuka; Watanabe, Takeo

    2015-07-22

    Visual perceptual learning (VPL) is defined as long-term improvement in performance on a visual-perception task after visual experiences or training. Early studies have found that VPL is highly specific for the trained feature and location, suggesting that VPL is associated with changes in the early visual cortex. However, the generality of visual skills enhancement attributable to action video-game experience suggests that VPL can result from improvement in higher cognitive skills. If so, experience in real-time strategy (RTS) video-game play, which may heavily involve cognitive skills, may also facilitate VPL. To test this hypothesis, we compared VPL between RTS video-game players (VGPs) and non-VGPs (NVGPs) and elucidated underlying structural and functional neural mechanisms. Healthy young human subjects underwent six training sessions on a texture discrimination task. Diffusion-tensor and functional magnetic resonance imaging were performed before and after training. VGPs performed better than NVGPs in the early phase of training. White-matter connectivity between the right external capsule and visual cortex and neuronal activity in the right inferior frontal gyrus (IFG) and anterior cingulate cortex (ACC) were greater in VGPs than NVGPs and were significantly correlated with RTS video-game experience. In both VGPs and NVGPs, there was task-related neuronal activity in the right IFG, ACC, and striatum, which was strengthened after training. These results indicate that RTS video-game experience, associated with changes in higher-order cognitive functions and connectivity between visual and cognitive areas, facilitates VPL in early phases of training. The results support the hypothesis that VPL can occur without involvement of only visual areas. Significance statement: Although early studies found that visual perceptual learning (VPL) is associated with involvement of the visual cortex, generality of visual skills enhancement by action video-game experience

  12. A perceptual learning deficit in Chinese developmental dyslexia as revealed by visual texture discrimination training.

    Science.gov (United States)

    Wang, Zhengke; Cheng-Lai, Alice; Song, Yan; Cutting, Laurie; Jiang, Yuzheng; Lin, Ou; Meng, Xiangzhi; Zhou, Xiaolin

    2014-08-01

    Learning to read involves discriminating between different written forms and establishing connections with phonology and semantics. This process may be partially built upon visual perceptual learning, during which the ability to process the attributes of visual stimuli progressively improves with practice. The present study investigated to what extent Chinese children with developmental dyslexia have deficits in perceptual learning by using a texture discrimination task, in which participants were asked to discriminate the orientation of target bars. Experiment l demonstrated that, when all of the participants started with the same initial stimulus-to-mask onset asynchrony (SOA) at 300 ms, the threshold SOA, adjusted according to response accuracy for reaching 80% accuracy, did not show a decrement over 5 days of training for children with dyslexia, whereas this threshold SOA steadily decreased over the training for the control group. Experiment 2 used an adaptive procedure to determine the threshold SOA for each participant during training. Results showed that both the group of dyslexia and the control group attained perceptual learning over the sessions in 5 days, although the threshold SOAs were significantly higher for the group of dyslexia than for the control group; moreover, over individual participants, the threshold SOA negatively correlated with their performance in Chinese character recognition. These findings suggest that deficits in visual perceptual processing and learning might, in part, underpin difficulty in reading Chinese.

  13. Learning local appearances with sparse representation for robust and fast visual tracking.

    Science.gov (United States)

    Bai, Tianxiang; Li, You-Fu; Zhou, Xiaolong

    2015-04-01

    In this paper, we present a novel appearance model using sparse representation and online dictionary learning techniques for visual tracking. In our approach, the visual appearance is represented by sparse representation, and the online dictionary learning strategy is used to adapt the appearance variations during tracking. We unify the sparse representation and online dictionary learning by defining a sparsity consistency constraint that facilitates the generative and discriminative capabilities of the appearance model. An elastic-net constraint is enforced during the dictionary learning stage to capture the characteristics of the local appearances that are insensitive to partial occlusions. Hence, the target appearance is effectively recovered from the corruptions using the sparse coefficients with respect to the learned sparse bases containing local appearances. In the proposed method, the dictionary is undercomplete and can thus be efficiently implemented for tracking. Moreover, we employ a median absolute deviation based robust similarity metric to eliminate the outliers and evaluate the likelihood between the observations and the model. Finally, we integrate the proposed appearance model with the particle filter framework to form a robust visual tracking algorithm. Experiments on benchmark video sequences show that the proposed appearance model outperforms the other state-of-the-art approaches in tracking performance.

  14. From Agents to Continuous Change via Aesthetics: Learning Mechanics with Visual Agentbased Computational Modeling

    CERN Document Server

    Sengupta, Pratim; Wright, Mason

    2013-01-01

    Novice learners find motion as a continuous process of change challenging to understand. In this paper, we present a pedagogical approach based on agent-based, visual programming to address this issue. Integrating Logo programming with curricular science has been shown to be challenging in previous research on educational computing. We present a new Logo-based visual programming language - ViMAP - and, a sequence of learning activities involving programming and modeling, designed specifically to support seamless integration between programming and learning kinematics. We describe relevant affordances of the ViMAP environment that supports such seamless integration. We then present ViMAP-MoMo, a curricular unit designed in ViMAP for modeling kinematics, for a wide range of students (elementary - high school). The main contribution of this paper is that we describe in detail a sequence of learning activities in three phases, discuss the underlying rationale for each phase, and where relevant, report results in ...

  15. Estimation of mental effort in learning visual search by measuring pupil response.

    Directory of Open Access Journals (Sweden)

    Tatsuto Takeuchi

    Full Text Available Perceptual learning refers to the improvement of perceptual sensitivity and performance with training. In this study, we examined whether learning is accompanied by a release from mental effort on the task, leading to automatization of the learned task. For this purpose, we had subjects conduct a visual search for a target, defined by a combination of orientation and spatial frequency, while we monitored their pupil size. It is well known that pupil size reflects the strength of mental effort invested in a task. We found that pupil size increased rapidly as the learning proceeded in the early phase of training and decreased at the later phase to a level half of its maximum value. This result does not support the simple automatization hypothesis. Instead, it suggests that the mental effort and behavioral performance reflect different aspects of perceptual learning. Further, mental effort would be continued to be invested to maintain good performance at a later stage of training.

  16. Learned filters for object detection in multi-object visual tracking

    Science.gov (United States)

    Stamatescu, Victor; Wong, Sebastien; McDonnell, Mark D.; Kearney, David

    2016-05-01

    We investigate the application of learned convolutional filters in multi-object visual tracking. The filters were learned in both a supervised and unsupervised manner from image data using artificial neural networks. This work follows recent results in the field of machine learning that demonstrate the use learned filters for enhanced object detection and classification. Here we employ a track-before-detect approach to multi-object tracking, where tracking guides the detection process. The object detection provides a probabilistic input image calculated by selecting from features obtained using banks of generative or discriminative learned filters. We present a systematic evaluation of these convolutional filters using a real-world data set that examines their performance as generic object detectors.

  17. Enhanced extinction of aversive memories by high-frequency stimulation of the rat infralimbic cortex.

    Directory of Open Access Journals (Sweden)

    Mouna Maroun

    Full Text Available Electrical stimulation of the rodent medial prefrontal cortex (mPFC, including the infralimbic cortex (IL, immediately prior to or during fear extinction training facilitates extinction memory. Here we examined the effects of high-frequency stimulation (HFS of the rat IL either prior to conditioning or following retrieval of the conditioned memory, on extinction of Pavlovian fear and conditioned taste aversion (CTA. IL-HFS applied immediately after fear memory retrieval, but not three hours after retrieval or prior to conditioning, subsequently reduced freezing during fear extinction. Similarly, IL-HFS given immediately, but not three hours after, retrieval of a CTA memory reduced aversion during extinction. These data indicate that HFS of the IL may be an effective method for reducing both learned fear and learned aversion.

  18. Visual event-related potential studies supporting the validity of VARK learning styles' visual and read/write learners.

    Science.gov (United States)

    Thepsatitporn, Sarawin; Pichitpornchai, Chailerd

    2016-06-01

    The validity of learning styles needs supports of additional objective evidence. The identification of learning styles using subjective evidence from VARK questionnaires (where V is visual, A is auditory, R is read/write, and K is kinesthetic) combined with objective evidence from visual event-related potential (vERP) studies has never been investigated. It is questionable whether picture superiority effects exist in V learners and R learners. Thus, the present study aimed to investigate whether vERP could show the relationship between vERP components and VARK learning styles and to identify the existence of picture superiority effects in V learners and R learners. Thirty medical students (15 V learners and 15 R learners) performed recognition tasks with vERP and an intermediate-term memory (ITM) test. The results of within-group comparisons showed that pictures elicited larger P200 amplitudes than words at the occipital 2 site (P < 0.05) in V learners and at the occipital 1 and 2 sites (P < 0.05) in R learners. The between-groups comparison showed that P200 amplitudes elicited by pictures in V learners were larger than those of R learners at the parietal 4 site (P < 0.05). The ITM test result showed that a picture set showed distinctively more correct responses than that of a word set for both V learners (P < 0.001) and R learners (P < 0.01). In conclusion, the result indicated that the P200 amplitude at the parietal 4 site could be used to objectively distinguish V learners from R learners. A lateralization existed to the right brain (occipital 2 site) in V learners. The ITM test demonstrated the existence of picture superiority effects in both learners. The results revealed the first objective electrophysiological evidence partially supporting the validity of the subjective psychological VARK questionnaire study.

  19. Robust Visual Tracking Via Consistent Low-Rank Sparse Learning

    KAUST Repository

    Zhang, Tianzhu

    2014-06-19

    Object tracking is the process of determining the states of a target in consecutive video frames based on properties of motion and appearance consistency. In this paper, we propose a consistent low-rank sparse tracker (CLRST) that builds upon the particle filter framework for tracking. By exploiting temporal consistency, the proposed CLRST algorithm adaptively prunes and selects candidate particles. By using linear sparse combinations of dictionary templates, the proposed method learns the sparse representations of image regions corresponding to candidate particles jointly by exploiting the underlying low-rank constraints. In addition, the proposed CLRST algorithm is computationally attractive since temporal consistency property helps prune particles and the low-rank minimization problem for learning joint sparse representations can be efficiently solved by a sequence of closed form update operations. We evaluate the proposed CLRST algorithm against 14 state-of-the-art tracking methods on a set of 25 challenging image sequences. Experimental results show that the CLRST algorithm performs favorably against state-of-the-art tracking methods in terms of accuracy and execution time.

  20. Small Stakes Risk Aversion in the Laboratory

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Lau, Morten; Ross, Don

    the “risk aversion temperature” of the subject. We consider evidence from a simple design that tests this assumption. We find that the assumption is strikingly rejected for a large sample of subjects from a population of college students. However, we find that the assumption is not rejected for a large......Evidence of risk aversion in laboratory settings over small stakes leads to a priori implausible levels of risk aversion over large stakes under certain assumptions. One core assumption in standard statements of this calibration puzzle is that individuals define utility over terminal wealth...... all levels of wealth, or over a “sufficiently large” range of wealth. Although this second assumption if often viewed as self-evident from the vast experimental literature showing risk aversion over laboratory stakes, it actually requires that lab wealth be varied for a given subject as one takes...

  1. Neural activations during visual sequence learning leave a trace in post-training spontaneous EEG.

    Directory of Open Access Journals (Sweden)

    Clara Moisello

    Full Text Available Recent EEG studies have shown that implicit learning involving specific cortical circuits results in an enduring local trace manifested as local changes in spectral power. Here we used a well characterized visual sequence learning task and high density-(hd-EEG recording to determine whether also declarative learning leaves a post-task, local change in the resting state oscillatory activity in the areas involved in the learning process. Thus, we recorded hd-EEG in normal subjects before, during and after the acquisition of the order of a fixed spatial target sequence (VSEQ and during the presentation of targets in random order (VRAN. We first determined the temporal evolution of spectral changes during VSEQ and compared it to VRAN. We found significant differences in the alpha and theta bands in three main scalp regions, a right occipito-parietal (ROP, an anterior-frontal (AFr, and a right frontal (RFr area. The changes in frontal theta power during VSEQ were positively correlated with the learning rate. Further, post-learning EEG recordings during resting state revealed a significant increase in alpha power in ROP relative to a pre-learning baseline. We conclude that declarative learning is associated with alpha and theta changes in frontal and posterior regions that occur during the task, and with an increase of alpha power in the occipito-parietal region after the task. These post-task changes may represent a trace of learning and a hallmark of use-dependent plasticity.

  2. Unemployment Benefits, Risk Aversion, and Migration Incentives

    OpenAIRE

    Heitmüller, Axel

    2002-01-01

    With reference to the EU enlargement, a framework is derived which allows the study of the effect of unemployment benefits on the migration decision. While benefits simply increase the expected gain for risk neutral individuals, they work as an insurance device for risk averse migrants; the results for the two groups might differ. Thus, the migration decision is reformulated as monetary lottery and a utility function exhibiting constant relative risk aversion is applied. The model suggests in...

  3. Organization of neural systems for aversive information processing: pain, error, and punishment

    Directory of Open Access Journals (Sweden)

    Shunsuke eKobayashi

    2012-09-01

    Full Text Available The avoidance of aversive events is critically important for the survival of organisms. It has been proposed that the medial pain system, including the amygdala, periaqueductal gray (PAG, and anterior cingulate cortex (ACC, contains the neural circuitry that signals pain affect and negative value. This system appears to have multiple defense mechanisms, such as rapid stereotyped escape, aversive association learning, and cognitive adaptation. These defense mechanisms vary in speed and flexibility, reflecting different strategies of self-protection. Over the course of evolution, the medial pain system appears to have developed primitive, associative, and cognitive solutions for aversive avoidance. There may be a functional grading along the caudal-rostral axis, such that the amygdala-PAG system underlies automatic and autonomic responses, the amygdala-orbitofrontal system contributes to associative learning, and the ACC controls cognitive processes in cooperation with the lateral prefrontal cortex. A review of behavioral and physiological studies on the aversive system is presented, and a conceptual framework for understanding the neural organization of the aversive avoidance system is proposed.

  4. Network changes in the transition from initial learning to well-practiced visual categorization

    Directory of Open Access Journals (Sweden)

    Joseph M DeGutis

    2009-11-01

    Full Text Available Visual categorization is a remarkable ability that allows us to effortlessly identify objects and efficiently respond to our environment. The neural mechanisms of how visual categories become well-established are largely unknown. Studies of initial category learning implicate a network of regions that include inferior temporal cortex (ITC, medial temporal lobe (MTL, basal ganglia (BG, premotor cortex (PMC and prefrontal cortex (PFC. However, how these regions change with extended learning is poorly characterized. To understand the neural changes in the transition from initially learned to well-practiced categorization, we used functional MRI and compared brain activity and functional connectivity when subjects performed an initially learned categorization task (100 trials of training and a well-practiced task (4250 trials of training. We demonstrate that a similar network is implicated for initially learned and well-practiced categorization. Additionally, connectivity analyses reveal an increased coordination between ITC, MTL, and PMC when making category judgments during the well-practiced task. These results suggest that category learning involves an increased coordination between a distributed network of regions supporting retrieval and representation of categories.

  5. Network changes in the transition from initial learning to well-practiced visual categorization.

    Science.gov (United States)

    DeGutis, Joe; D'Esposito, Mark

    2009-01-01

    Visual categorization is a remarkable ability that allows us to effortlessly identify objects and efficiently respond to our environment. The neural mechanisms of how visual categories become well-established are largely unknown. Studies of initial category learning implicate a network of regions that include inferior temporal cortex (ITC), medial temporal lobe (MTL), basal ganglia (BG), premotor cortex (PMC) and prefrontal cortex (PFC). However, how these regions change with extended learning is poorly characterized. To understand the neural changes in the transition from initially learned to well-practiced categorization, we used functional MRI and compared brain activity and functional connectivity when subjects performed an initially learned categorization task (100 trials of training) and a well-practiced task (4250 trials of training). We demonstrate that a similar network is implicated for initially learned and well-practiced categorization. Additionally, connectivity analyses reveal an increased coordination between ITC, MTL, and PMC when making category judgments during the well-practiced task. These results suggest that category learning involves an increased coordination between a distributed network of regions supporting retrieval and representation of categories.

  6. Figure analysis: A teaching technique to promote visual literacy and active Learning.

    Science.gov (United States)

    Wiles, Amy M

    2016-07-01

    Learning often improves when active learning techniques are used in place of traditional lectures. For many of these techniques, however, students are expected to apply concepts that they have already grasped. A challenge, therefore, is how to incorporate active learning into the classroom of courses with heavy content, such as molecular-based biology courses. An additional challenge is that visual literacy is often overlooked in undergraduate science education. To address both of these challenges, a technique called figure analysis was developed and implemented in three different levels of undergraduate biology courses. Here, students learn content while gaining practice in interpreting visual information by discussing figures with their peers. Student groups also make connections between new and previously learned concepts on their own while in class. The instructor summarizes the material for the class only after students grapple with it in small groups. Students reported a preference for learning by figure analysis over traditional lecture, and female students in particular reported increased confidence in their analytical abilities. There is not a technology requirement for this technique; therefore, it may be utilized both in classrooms and in nontraditional spaces. Additionally, the amount of preparation required is comparable to that of a traditional lecture. © 2016 by The International Union of Biochemistry and Molecular Biology, 44(4):336-344, 2016.

  7. Explaining neural signals in human visual cortex with an associative learning model.

    Science.gov (United States)

    Jiang, Jiefeng; Schmajuk, Nestor; Egner, Tobias

    2012-08-01

    "Predictive coding" models posit a key role for associative learning in visual cognition, viewing perceptual inference as a process of matching (learned) top-down predictions (or expectations) against bottom-up sensory evidence. At the neural level, these models propose that each region along the visual processing hierarchy entails one set of processing units encoding predictions of bottom-up input, and another set computing mismatches (prediction error or surprise) between predictions and evidence. This contrasts with traditional views of visual neurons operating purely as bottom-up feature detectors. In support of the predictive coding hypothesis, a recent human neuroimaging study (Egner, Monti, & Summerfield, 2010) showed that neural population responses to expected and unexpected face and house stimuli in the "fusiform face area" (FFA) could be well-described as a summation of hypothetical face-expectation and -surprise signals, but not by feature detector responses. Here, we used computer simulations to test whether these imaging data could be formally explained within the broader framework of a mathematical neural network model of associative learning (Schmajuk, Gray, & Lam, 1996). Results show that FFA responses could be fit very closely by model variables coding for conditional predictions (and their violations) of stimuli that unconditionally activate the FFA. These data document that neural population signals in the ventral visual stream that deviate from classic feature detection responses can formally be explained by associative prediction and surprise signals.

  8. Objects Classification by Learning-Based Visual Saliency Model and Convolutional Neural Network

    Science.gov (United States)

    Li, Na; Yang, Yongjia

    2016-01-01

    Humans can easily classify different kinds of objects whereas it is quite difficult for computers. As a hot and difficult problem, objects classification has been receiving extensive interests with broad prospects. Inspired by neuroscience, deep learning concept is proposed. Convolutional neural network (CNN) as one of the methods of deep learning can be used to solve classification problem. But most of deep learning methods, including CNN, all ignore the human visual information processing mechanism when a person is classifying objects. Therefore, in this paper, inspiring the completed processing that humans classify different kinds of objects, we bring forth a new classification method which combines visual attention model and CNN. Firstly, we use the visual attention model to simulate the processing of human visual selection mechanism. Secondly, we use CNN to simulate the processing of how humans select features and extract the local features of those selected areas. Finally, not only does our classification method depend on those local features, but also it adds the human semantic features to classify objects. Our classification method has apparently advantages in biology. Experimental results demonstrated that our method made the efficiency of classification improve significantly. PMID:27803711

  9. Visual Statistical Learning Works after Binding the Temporal Sequences of Shapes and Spatial Positions

    Directory of Open Access Journals (Sweden)

    Osamu Watanabe

    2011-05-01

    Full Text Available The human visual system can acquire the statistical structures in temporal sequences of object feature changes, such as changes in shape, color, and its combination. Here we investigate whether the statistical learning for spatial position and shape changes operates separately or not. It is known that the visual system processes these two types of information separately; the spatial information is processed in the parietal cortex, whereas object shapes and colors are detected in the temporal pathway, and, after that, we perceive bound information in the two streams. We examined whether the statistical learning operates before or after binding the shape and the spatial information by using the “re-paired triplet” paradigm proposed by Turk-Browne, Isola, Scholl, and Treat (2008. The result showed that observers acquired combined sequences of shape and position changes, but no statistical information in individual sequence was obtained. This finding suggests that the visual statistical learning works after binding the temporal sequences of shapes and spatial structures and would operate in the higher-order visual system; this is consistent with recent ERP (Abla & Okanoya, 2009 and fMRI (Turk-Browne, Scholl, Chun, & Johnson, 2009 studies.

  10. Influence of visual observational conditions on tongue motor learning

    DEFF Research Database (Denmark)

    Kothari, Mohit; Liu, Xuimei; Baad-Hansen, Lene;

    2016-01-01

    feedback of their own TPT performance, Group 3: control group performed the TPT without any conditioning. There was no overall difference between groups but TPT performance increased over time. A significant group x time interaction indicated that the self-observation group performed significantly better...... than the model-observation group in the last 20 min of TPT. The subject-based reports of video helpfulness showed that the model-observation group rated the pre-recorded video as more helpful for TPT performance compared with the other groups but there was no significant difference between groups...... regarding the level of disturbance, pain or fatigue. Self-observation of tongue-training facilitated behavioral aspects of tongue motor learning compared with model-observation but not compared with control....

  11. Biologically Inspired Model for Visual Cognition Achieving Unsupervised Episodic and Semantic Feature Learning.

    Science.gov (United States)

    Qiao, Hong; Li, Yinlin; Li, Fengfu; Xi, Xuanyang; Wu, Wei

    2016-10-01

    Recently, many biologically inspired visual computational models have been proposed. The design of these models follows the related biological mechanisms and structures, and these models provide new solutions for visual recognition tasks. In this paper, based on the recent biological evidence, we propose a framework to mimic the active and dynamic learning and recognition process of the primate visual cortex. From principle point of view, the main contributions are that the framework can achieve unsupervised learning of episodic features (including key components and their spatial relations) and semantic features (semantic descriptions of the key components), which support higher level cognition of an object. From performance point of view, the advantages of the framework are as follows: 1) learning episodic features without supervision-for a class of objects without a prior knowledge, the key components, their spatial relations and cover regions can be learned automatically through a deep neural network (DNN); 2) learning semantic features based on episodic features-within the cover regions of the key components, the semantic geometrical values of these components can be computed based on contour detection; 3) forming the general knowledge of a class of objects-the general knowledge of a class of objects can be formed, mainly including the key components, their spatial relations and average semantic values, which is a concise description of the class; and 4) achieving higher level cognition and dynamic updating-for a test image, the model can achieve classification and subclass semantic descriptions. And the test samples with high confidence are selected to dynamically update the whole model. Experiments are conducted on face images, and a good performance is achieved in each layer of the DNN and the semantic description learning process. Furthermore, the model can be generalized to recognition tasks of other objects with learning ability.

  12. Learner differences and learning outcomes in an introductory biochemistry class: attitude toward images, visual cognitive skills, and learning approach.

    Science.gov (United States)

    Milner, Rachel E

    2014-01-01

    The practice of using images in teaching is widespread, and in science education images are used so extensively that some have argued they are now the "main vehicle of communication" (C. Ferreira, A. Arroio Problems Educ. 21st Century 2009, 16, 48-53). Although this phenomenon is especially notable in the field of biochemistry, we know little about the role and importance of images in communicating concepts to students in the classroom. This study reports the development of a scale to assess students' attitude toward biochemical images, particularly their willingness and ability to use the images to support their learning. In addition, because it is argued that images are central in the communication of biochemical concepts, we investigated three "learner differences" which might impact learning outcomes in this kind of classroom environment: attitude toward images, visual cognitive skills, and learning approach. Overall, the students reported a positive attitude toward the images, the majority agreeing that they liked images and considered them useful. However, the participants also reported that verbal explanations were more important than images in helping them to understand the concepts. In keeping with this we found that there was no relationship between learning outcomes and the students' self-reported attitude toward images or visual cognitive skills. In contrast, learning outcomes were significantly correlated with the students' self-reported approach to learning. These findings suggest that images are not necessarily the main vehicle of communication in a biochemistry classroom and that verbal explanations and encouragement of a deep learning approach are important considerations in improving our pedagogical approach.

  13. Nonvisual motor learning improves visual motion perception: evidence from violating the two-thirds power law.

    Science.gov (United States)

    Beets, I A M; Rösler, F; Fiehler, K

    2010-09-01

    Few studies have reported direct effects of motor learning on visual perception, especially when using novel movements for the motor system. Atypical motor behaviors that violate movement constraints provide an excellent opportunity to study action-to-perception transfer. In our study, we passively trained blindfolded participants on movements violating the 2/3 power law. Before and after motor training, participants performed a visual discrimination task in which they decided whether two consecutive movements were same or different. For motor training, we randomly assigned the participants to two motor training groups or a control group. The motor training group experienced either a weak or a strong elliptic velocity profile on a circular trajectory that matched one of the visual test stimuli. The control group was presented with linear trajectories unrelated to the viewed movements. After each training session, participants actively reproduced the movement to assess motor learning. The group trained on the strong elliptic velocity profile reproduced movements with increasing elliptic velocity profiles while circular geometry remained constant. Furthermore, both training groups improved in visual discrimination ability for the learned movement as well as for highly similar movements. Participants in the control group, however, did not show any improvements in the visual discrimination task nor did participants who did not acquire the trained movement. The present results provide evidence for a transfer from action to perception which generalizes to highly related movements and depends on the success of motor learning. Moreover, under specific conditions, it seems to be possible to acquire movements deviating from the 2/3 power law.

  14. Sustained Cortical and Subcortical Measures of Auditory and Visual Plasticity following Short-Term Perceptual Learning.

    Science.gov (United States)

    Lau, Bonnie K; Ruggles, Dorea R; Katyal, Sucharit; Engel, Stephen A; Oxenham, Andrew J

    2017-01-01

    Short-term training can lead to improvements in behavioral discrimination of auditory and visual stimuli, as well as enhanced EEG responses to those stimuli. In the auditory domain, fluency with tonal languages and musical training has been associated with long-term cortical and subcortical plasticity, but less is known about the effects of shorter-term training. This study combined electroencephalography (EEG) and behavioral measures to investigate short-term learning and neural plasticity in both auditory and visual domains. Forty adult participants were divided into four groups. Three groups trained on one of three tasks, involving discrimination of auditory fundamental frequency (F0), auditory amplitude modulation rate (AM), or visual orientation (VIS). The fourth (control) group received no training. Pre- and post-training tests, as well as retention tests 30 days after training, involved behavioral discrimination thresholds, steady-state visually evoked potentials (SSVEP) to the flicker frequencies of visual stimuli, and auditory envelope-following responses simultaneously evoked and measured in response to rapid stimulus F0 (EFR), thought to reflect subcortical generators, and slow amplitude modulation (ASSR), thought to reflect cortical generators. Enhancement of the ASSR was observed in both auditory-trained groups, not specific to the AM-trained group, whereas enhancement of the SSVEP was found only in the visually-trained group. No evidence was found for changes in the EFR. The results suggest that some aspects of neural plasticity can develop rapidly and may generalize across tasks but not across modalities. Behaviorally, the pattern of learning was complex, with significant cross-task and cross-modal learning effects.

  15. Decoding the future from past experience: learning shapes predictions in early visual cortex.

    Science.gov (United States)

    Luft, Caroline D B; Meeson, Alan; Welchman, Andrew E; Kourtzi, Zoe

    2015-05-01

    Learning the structure of the environment is critical for interpreting the current scene and predicting upcoming events. However, the brain mechanisms that support our ability to translate knowledge about scene statistics to sensory predictions remain largely unknown. Here we provide evidence that learning of temporal regularities shapes representations in early visual cortex that relate to our ability to predict sensory events. We tested the participants' ability to predict the orientation of a test stimulus after exposure to sequences of leftward- or rightward-oriented gratings. Using fMRI decoding, we identified brain patterns related to the observers' visual predictions rather than stimulus-driven activity. Decoding of predicted orientations following structured sequences was enhanced after training, while decoding of cued orientations following exposure to random sequences did not change. These predictive representations appear to be driven by the same large-scale neural populations that encode actual stimulus orientation and to be specific to the learned sequence structure. Thus our findings provide evidence that learning temporal structures supports our ability to predict future events by reactivating selective sensory representations as early as in primary visual cortex.

  16. Attention Cueing and Activity Equally Reduce False Alarm Rate in Visual-Auditory Associative Learning through Improving Memory.

    Science.gov (United States)

    Nikouei Mahani, Mohammad-Ali; Haghgoo, Hojjat Allah; Azizi, Solmaz; Nili Ahmadabadi, Majid

    2016-01-01

    In our daily life, we continually exploit already learned multisensory associations and form new ones when facing novel situations. Improving our associative learning results in higher cognitive capabilities. We experimentally and computationally studied the learning performance of healthy subjects in a visual-auditory sensory associative learning task across active learning, attention cueing learning, and passive learning modes. According to our results, the learning mode had no significant effect on learning association of congruent pairs. In addition, subjects' performance in learning congruent samples was not correlated with their vigilance score. Nevertheless, vigilance score was significantly correlated with the learning performance of the non-congruent pairs. Moreover, in the last block of the passive learning mode, subjects significantly made more mistakes in taking non-congruent pairs as associated and consciously reported lower confidence. These results indicate that attention and activity equally enhanced visual-auditory associative learning for non-congruent pairs, while false alarm rate in the passive learning mode did not decrease after the second block. We investigated the cause of higher false alarm rate in the passive learning mode by using a computational model, composed of a reinforcement learning module and a memory-decay module. The results suggest that the higher rate of memory decay is the source of making more mistakes and reporting lower confidence in non-congruent pairs in the passive learning mode.

  17. Perceptual learning of Gabor orientation identification in visual periphery: complete inter-ocular transfer of learning mechanisms.

    Science.gov (United States)

    Lu, Zhong-Lin; Chu, Wilson; Dosher, Barbara Anne; Lee, Sophia

    2005-09-01

    We combined the external noise paradigm, the Perceptual Template Model approach, and transfer tests to investigate the mechanisms and eye-specificity of perceptual learning of Gabor orientation in visual periphery. Coupled with a fixation task, discriminating a 5 from an S in a rapid small character string at fixation, contrast thresholds were estimated for each of eight external noise levels at two performance criteria using 3/1 and 2/1 staircases. Perceptual learning in one eye was measured over 10 practice sessions, followed by five sessions of practice in the new eye to assess transfer. We found that monocular learning improved performance (reduced contrast thresholds) with virtually equal magnitude across a wide range of external noise levels with no significant change in central task performance. Based on measurements of learning effects at two performance criterion levels, we identified a mixture of stimulus enhancement and external noise exclusion as the mechanism of perceptual learning underlying the observed improvements. Perceptual learning in the trained eye generalized completely to the untrained eye. We related the transfer patterns to known physiology and psychophysics on orientation direction coding.

  18. Glucocorticoids Enhance Taste Aversion Memory via Actions in the Insular Cortex and Basolateral Amygdala

    Science.gov (United States)

    Miranda, Maria Isabel; Quirarte, Gina L.; Rodriguez-Garcia, Gabriela; McGaugh, James L.; Roozendaal, Benno

    2008-01-01

    It is well established that glucocorticoid hormones strengthen the consolidation of hippocampus-dependent spatial and contextual memory. The present experiments investigated glucocorticoid effects on the long-term formation of conditioned taste aversion (CTA), an associative learning task that does not depend critically on hippocampal function.…

  19. Emotional reactivity and cognitive performance in aversively motivated tasks: a comparison between four rat strains

    NARCIS (Netherlands)

    Staay, van der F.J.; Schuurman, T.; Reenen, van C.G.; Korte, S.M.

    2009-01-01

    Background - Cognitive function might be affected by the subjects' emotional reactivity. We assessed whether behavior in different tests of emotional reactivity is correlated with performance in aversively motivated learning tasks, using four strains of rats generally considered to have a different

  20. Steroid Hormone (20-Hydroxyecdysone) Modulates the Acquisition of Aversive Olfactory Memories in Pollen Forager Honeybees

    Science.gov (United States)

    Geddes, Lisa H.; McQuillan, H. James; Aiken, Alastair; Vergoz, Vanina; Mercer, Alison R.

    2013-01-01

    Here, we examine effects of the steroid hormone, 20-hydroxyecdysone (20-E), on associative olfactory learning in the honeybee, "Apis mellifera." 20-E impaired the bees' ability to associate odors with punishment during aversive conditioning, but did not interfere with their ability to associate odors with a food reward (appetitive…

  1. Learning to learn during visual discrimination in group housed dwarf goats (Capra hircus).

    Science.gov (United States)

    Langbein, Jan; Siebert, Katrin; Nürnberg, Gerd; Manteuffel, Gerhard

    2007-11-01

    Using an automated learning device, we investigated "learning to learn" by dwarf goats (Capra hircus) in what was for them a familiar environment and normal social settings. Nine problems, each consisting of four discriminable black symbols, each with one S-super+ and three different S-super(-), were presented on a computer screen. Mean daily learning success improved over the course of the first four problems, and the improvement was maintained throughout the remaining five problems. The number of trials to reach the learning criterion decreased significantly beginning with problem four. Such results may be interpreted as evidence that the goats were developing a learning set. In the present case, the learning set appeared to have two components. One involved gaining familiarity and apparent understanding of the learning device and the basic requirements of the discrimination task. The second component involved learning potential error factors to be ignored, as well as learning commonalities that carried over from one problem to the next. Among the error factors, evidence of apparent preferences for specific symbols was seen, which had a predictable effect on performances.

  2. Different levels of food restriction reveal genotype-specific differences in learning a visual discrimination task.

    Directory of Open Access Journals (Sweden)

    Kalina Makowiecki

    Full Text Available In behavioural experiments, motivation to learn can be achieved using food rewards as positive reinforcement in food-restricted animals. Previous studies reduce animal weights to 80-90% of free-feeding body weight as the criterion for food restriction. However, effects of different degrees of food restriction on task performance have not been assessed. We compared learning task performance in mice food-restricted to 80 or 90% body weight (BW. We used adult wildtype (WT; C57Bl/6j and knockout (ephrin-A2⁻/⁻ mice, previously shown to have a reverse learning deficit. Mice were trained in a two-choice visual discrimination task with food reward as positive reinforcement. When mice reached criterion for one visual stimulus (80% correct in three consecutive 10 trial sets they began the reverse learning phase, where the rewarded stimulus was switched to the previously incorrect stimulus. For the initial learning and reverse phase of the task, mice at 90%BW took almost twice as many trials to reach criterion as mice at 80%BW. Furthermore, WT 80 and 90%BW groups significantly differed in percentage correct responses and learning strategy in the reverse learning phase, whereas no differences between weight restriction groups were observed in ephrin-A2⁻/⁻ mice. Most importantly, genotype-specific differences in reverse learning strategy were only detected in the 80%BW groups. Our results indicate that increased food restriction not only results in better performance and a shorter training period, but may also be necessary for revealing behavioural differences between experimental groups. This has important ethical and animal welfare implications when deciding extent of diet restriction in behavioural studies.

  3. Interacting Effects of Instructions and Presentation Rate on Visual Statistical Learning

    Directory of Open Access Journals (Sweden)

    Julie eBertels

    2015-11-01

    Full Text Available The statistical regularities of a sequence of visual shapes can be learned incidentally. Arciuli et al. (2014 recently argued that intentional instructions only improve learning at slow presentation rates as they favor the use of explicit strategies. The aim of the present study was (1 to test this assumption directly by investigating how instructions (incidental vs. intentional and presentation rate (fast vs. slow affect the acquisition of knowledge and (2 to examine how these factors influence the conscious vs. unconscious nature of the knowledge acquired. To this aim, we exposed participants to four triplets of shapes, presented sequentially in a pseudo-random order, and assessed their degree of learning in a subsequent completion task that integrated confidence judgments. Supporting Arciuli et al.’s claim, participant performance only benefited from intentional instructions at slow presentation rates. Moreover, informing participants beforehand about the existence of statistical regularities increased their explicit knowledge of the sequences, an effect that was not modulated by presentation speed. These results support that, although visual statistical learning can take place incidentally and, to some extent, outside conscious awareness, factors such as presentation rate and prior knowledge can boost learning of these regularities, presumably by favoring the acquisition of explicit knowledge.

  4. Learning to perform a new movement with robotic assistance: comparison of haptic guidance and visual demonstration

    Directory of Open Access Journals (Sweden)

    Reinkensmeyer DJ

    2006-08-01

    Full Text Available Abstract Background Mechanical guidance with a robotic device is a candidate technique for teaching people desired movement patterns during motor rehabilitation, surgery, and sports training, but it is unclear how effective this approach is as compared to visual demonstration alone. Further, little is known about motor learning and retention involved with either robot-mediated mechanical guidance or visual demonstration alone. Methods Healthy subjects (n = 20 attempted to reproduce a novel three-dimensional path after practicing it with mechanical guidance from a robot. Subjects viewed their arm as the robot guided it, so this "haptic guidance" training condition provided both somatosensory and visual input. Learning was compared to reproducing the movement following only visual observation of the robot moving along the path, with the hand in the lap (the "visual demonstration" training condition. Retention was assessed periodically by instructing the subjects to reproduce the path without robotic demonstration. Results Subjects improved in ability to reproduce the path following practice in the haptic guidance or visual demonstration training conditions, as evidenced by a 30–40% decrease in spatial error across 126 movement attempts in each condition. Performance gains were not significantly different between the two techniques, but there was a nearly significant trend for the visual demonstration condition to be better than the haptic guidance condition (p = 0.09. The 95% confidence interval of the mean difference between the techniques was at most 25% of the absolute error in the last cycle. When asked to reproduce the path repeatedly following either training condition, the subjects' performance degraded significantly over the course of a few trials. The tracing errors were not random, but instead were consistent with a systematic evolution toward another path, as if being drawn to an "attractor path". Conclusion These results indicate

  5. Long-term changes in amphetamine-induced reinforcement and aversion in rats following exposure to 56Fe particle

    Science.gov (United States)

    Rabin, B. M.; Joseph, J. A.; Shukitt-Hale, B.

    Exposing rats to heavy particles produces alterations in the functioning of dopaminergic neurons and in the behaviors that depend upon the integrity of the dopaminergic system. Two of these dopamine-dependent behaviors include amphetamine-induced reinforcement, measure using the conditioned place preference procedure, and amphetamine-induced reinforcement, measured using the conditioned place preference procedure, and amphetamine-induced aversion, measured using the conditioned taste aversion. Previous research has shown that exposing rats to 1.0 Gy of 1GeV/n 56Fe particles produced a disruption of an amphetamine-induced taste aversion 3 days following exposure, but produced an apparent enhancement of the aversion 112 days following exposure. The present experiments were designed to provide a further evaluation of these results by examining taste aversion learning 154 days following exposure to 1.0Gy 56Fe particles and to establish the convergent validity of the taste aversion results by looking at the effects of exposure on the establishment of an amphetamine-induced conditioned place preference 3, 7, and 16 weeks following irradiation. The taste aversion results failed to confirm the apparent enhancement of the amphetamine-induced CTA observed in the prior experiment. However, exposure to 56Fe particles prevented the acquisition of amphetamine-induced place preference at all three-time intervals. The results are interpreted as indicating that exposure to heavy particles can produce long-term changes in behavioral functioning.

  6. Reading speed in the peripheral visual field of older adults: Does it benefit from perceptual learning?

    OpenAIRE

    Yu, Deyue; Cheung, Sing-Hang; Legge, Gordon E; Chung, Susana T.L.

    2010-01-01

    Enhancing reading ability in peripheral vision is important for the rehabilitation of people with central-visual-field loss from age-related macular degeneration (AMD). Previous research has shown that perceptual learning, based on a trigram letter-recognition task, improved peripheral reading speed among normally-sighted young adults (Chung, Legge, & Cheung, 2004). Here we ask whether the same happens in older adults in an age range more typical of the onset of AMD. Eighteen normally-sighted...

  7. The Effect of Visual and Etymological Treatments on Learning Decomposable Idioms among EFL Learners

    OpenAIRE

    Nassim Golaghaei; Sedigheh Kakolian

    2015-01-01

    The present study endeavors to investigate the impact of visual and etymological treatments on learning idioms among English language learners. Seventy-nine intermediate students at Rooz Academy Language School in Babol were selected from among a total number of 116 learners based on their performances on the Longman complete course for the TOEFL test to fulfill the purpose of the study. The students were then assigned into three experimental groups. Initially, a pre-test of idiomatic express...

  8. Simulating Visual Learning and Optical Illusions via a Network-Based Genetic Algorithm

    Science.gov (United States)

    Siu, Theodore; Vivar, Miguel; Shinbrot, Troy

    We present a neural network model that uses a genetic algorithm to identify spatial patterns. We show that the model both learns and reproduces common visual patterns and optical illusions. Surprisingly, we find that the illusions generated are a direct consequence of the network architecture used. We discuss the implications of our results and the insights that we gain on how humans fall for optical illusions

  9. Broad-based visual benefits from training with an integrated perceptual-learning video game

    Science.gov (United States)

    Deveau, Jenni; Lovcik, Gary; Seitz, Aaron R.

    2014-01-01

    Perception is the window through which we understand all information about our environment, and therefore deficits in perception due to disease, injury, stroke or aging can have significant negative impacts on individuals’ lives. Research in the field of perceptual learning has demonstrated that vision can be improved in both normally seeing and visually impaired individuals, however, a limitation of most perceptual learning approaches is their emphasis on isolating particular mechanisms. In the current study, we adopted an integrative approach where the goal is not to achieve highly specific learning but instead to achieve general improvements to vision. We combined multiple perceptual learning approaches that have individually contributed to increasing the speed, magnitude and generality of learning into a perceptual-learning based video-game. Our results demonstrate broad-based benefits of vision in a healthy adult population. Transfer from the game includes; improvements in acuity (measured with self-paced standard eye-charts), improvement along the full contrast sensitivity function, and improvements in peripheral acuity and contrast thresholds. The use of this type of this custom video game framework built up from psychophysical approaches takes advantage of the benefits found from video game training while maintaining a tight link to psychophysical designs that enable understanding of mechanisms of perceptual learning and has great potential both as a scientific tool and as therapy to help improve vision. PMID:24406157

  10. Broad-based visual benefits from training with an integrated perceptual-learning video game.

    Science.gov (United States)

    Deveau, Jenni; Lovcik, Gary; Seitz, Aaron R

    2014-06-01

    Perception is the window through which we understand all information about our environment, and therefore deficits in perception due to disease, injury, stroke or aging can have significant negative impacts on individuals' lives. Research in the field of perceptual learning has demonstrated that vision can be improved in both normally seeing and visually impaired individuals, however, a limitation of most perceptual learning approaches is their emphasis on isolating particular mechanisms. In the current study, we adopted an integrative approach where the goal is not to achieve highly specific learning but instead to achieve general improvements to vision. We combined multiple perceptual learning approaches that have individually contributed to increasing the speed, magnitude and generality of learning into a perceptual-learning based video-game. Our results demonstrate broad-based benefits of vision in a healthy adult population. Transfer from the game includes; improvements in acuity (measured with self-paced standard eye-charts), improvement along the full contrast sensitivity function, and improvements in peripheral acuity and contrast thresholds. The use of this type of this custom video game framework built up from psychophysical approaches takes advantage of the benefits found from video game training while maintaining a tight link to psychophysical designs that enable understanding of mechanisms of perceptual learning and has great potential both as a scientific tool and as therapy to help improve vision.

  11. Learning representation hierarchies by sharing visual features: a computational investigation of Persian character recognition with unsupervised deep learning.

    Science.gov (United States)

    Sadeghi, Zahra; Testolin, Alberto

    2017-02-25

    In humans, efficient recognition of written symbols is thought to rely on a hierarchical processing system, where simple features are progressively combined into more abstract, high-level representations. Here, we present a computational model of Persian character recognition based on deep belief networks, where increasingly more complex visual features emerge in a completely unsupervised manner by fitting a hierarchical generative model to the sensory data. Crucially, high-level internal representations emerging from unsupervised deep learning can be easily read out by a linear classifier, achieving state-of-the-art recognition accuracy. Furthermore, we tested the hypothesis that handwritten digits and letters share many common visual features: A generative model that captures the statistical structure of the letters distribution should therefore also support the recognition of written digits. To this aim, deep networks trained on Persian letters were used to build high-level representations of Persian digits, which were indeed read out with high accuracy. Our simulations show that complex visual features, such as those mediating the identification of Persian symbols, can emerge from unsupervised learning in multilayered neural networks and can support knowledge transfer across related domains.

  12. Learning about “wicked” problems in the Global South. Creating a film-based learning environment with “Visual Problem Appraisal”

    Directory of Open Access Journals (Sweden)

    Loes Witteveen

    2012-03-01

    Full Text Available The current complexity of sustainable development in the Global South calls for the design of learning strategies that can deal with this complexity. One such innovative learning strategy, called Visual Problem Appraisal (VPA, is highlighted in this article. The strategy is termed visual as it creates a learning environment that is film-based. VPA enhances the analysis of complex issues, and facilitates stakeholder dialogue and action planning. The strategy is used in workshops dealing with problem analysis and policy design, and involves the participants “meeting” stakeholders through filmed narratives. The article demonstrates the value of using film in multi stakeholder learning environments addressing issues concerning sustainable development.

  13. Designing a web-based learning portal for geographic visualization and analysis in public health.

    Science.gov (United States)

    Robinson, Anthony C; MacEachren, Alan M; Roth, Robert E

    2011-09-01

    Interactive mapping and spatial analysis tools are under-utilized by health researchers and decision-makers as a result of scarce training materials, few examples demonstrating the successful use of geographic visualization, and poor mechanisms for sharing results generated by geovisualization. Here, we report on the development of the Geovisual EXplication(G-EX) Portal, a web-based application designed to connect researchers in geovisualization and related mapping sciences, to users who are working in public health and epidemiology. This paper focuses on the design and development of the G-EX Portal Learn module, a set of tools intended to disseminate learning artifacts. Initial design and development of the G-EX Portal has been guided by our past research on the use and usability of geovisualization in public health. As part of the iterative design and development process, we conducted a needs assessment survey with targeted end-users, which we report on here. The survey focused on users' current learning habits, their preferred kind of learning artifacts and issues they may have with contributing learning artifacts to web portals. Survey results showed that users desire a diverse set of learning artifacts in terms of both formats and topics covered. Results also revealed a willingness of users to contribute both learning artifacts and personal information that would help other users to evaluate the credibility of the learning artifact source. We include a detailed description of the G-EX Portal Learn module and focus on modifications to the design of the Learn module as a result from feedback we received from our survey.

  14. Feature-saliency and feedback-information interactively impact visual category learning

    Directory of Open Access Journals (Sweden)

    Rubi eHammer

    2015-02-01

    Full Text Available Visual category learning (VCL involves detecting which features are most relevant for categorization. This requires attentional learning, which allows effectively redirecting attention to object’s features most relevant for categorization while also filtering out irrelevant features. When features relevant for categorization are not salient VCL relies also on perceptual learning, which enable becoming more sensitive to subtle yet important differences between objects. Little is known about how attentional learning and perceptual learning interact when VCL relies on both processes at the same time. Here we tested this interaction. Participants performed VCL tasks that varied in feature-saliency (low-saliency tasks that required perceptual learning vs. high-saliency tasks, and in feedback-information (tasks with mid-information, moderately ambiguous feedback that increased attentional load vs. tasks with high-information non-ambiguous feedback. Participants were required learning to categorize novel stimuli by detecting the feature-dimension relevant for categorization. We found that mid-information and high-information feedback were similarly effective for VCL in high-saliency tasks. This suggests that an increased attentional load associated with the processing of moderately ambiguous feedback does not compromise VCL when both the task relevant feature and irrelevant features are salient. In low-saliency VCL tasks performance improvement relied on slower perceptual learning, but when the feedback was highly-informative participants were ultimately capable reaching performances matching those observed in high-saliency VCL tasks. However, VCL was much compromised when features were with low-saliency and the feedback was ambiguous. We suggest that this later learning scenario is characterized by a ‘cognitive loop paradox’ where two interdependent learning processes have to take place simultaneously.

  15. Reference-dependent preferences and loss aversion

    Directory of Open Access Journals (Sweden)

    Einat Neuman

    2008-02-01

    Full Text Available This study employs a Discrete Choice Experiment (DCE in the health-care sector to test the loss aversion theory that is derived from reference-dependent preferences: The absolute subjective value of a deviation from a reference point is generally greater when the deviation represents a loss than when the same-sized change is perceived as a gain. As far as is known, this paper is the first to use a DCE to test the loss aversion theory. A DCE is a highly suitable tool for such testing because it estimates the marginal valuations of attributes, based onextit{ deviations from a reference point} (a constant scenario. Moreover, loss aversion can be examined for extit{each attribute separately}. Another advantage of a DCE is that is can be applied toextit{ non-traded goods with non-tangible attributes}. A health-care event is used for empirical illustration: The loss aversion theory is tested within the context of preference structures for maternity-ward attributes, estimated using data gathered from 3850 observations made by a sample of 542 women who had recently given birth. Seven hypotheses are presented and tested. Overall, significant support for behavioral loss aversion theories was found. %JEL codes: D01, D12, I19

  16. How does economic risk aversion affect biodiversity?

    Science.gov (United States)

    Mouysset, L; Doyen, L; Jiguet, F

    2013-01-01

    Significant decline of biodiversity in farmlands has been reported for several decades. To limit the negative impact of agriculture, many agro-environmental schemes have been implemented, but their effectiveness remains controversial. In this context, the study of economic drivers is helpful to understand the role played by farming on biodiversity. The present paper analyzes the impact of risk aversion on farmland biodiversity. Here "risk aversion" means a cautious behavior of farmers facing uncertainty. We develop a bio-economic model that articulates bird community dynamics and representative farmers selecting land uses within an uncertain macro-economic context. It is specialized and calibrated at a regional scale for France through national databases. The influence of risk aversion is assessed on ecological, agricultural, and economic outputs through projections at the 2050 horizon. A high enough risk aversion appears sufficient to both manage economic risk and promote ecological performance. This occurs through a diversification mechanism on regional land uses. However, economic calibration leads to a weak risk-aversion parameter, which is consistent with the current decline of farmland birds. Spatial disparities however suggest that public incentives could be necessary to reinforce the diversification and bio-economic effectiveness.

  17. Do fish perceive anaesthetics as aversive?

    Directory of Open Access Journals (Sweden)

    Gareth D Readman

    Full Text Available This study addresses a fundamental question in fish welfare: are the anaesthetics used for fish aversive? Despite years of routine general use of many agents, within both scientific research and aquaculture, there is a paucity of information regarding their tolerance and associated behavioural responses by fish. This study examined nine of the most commonly used fish anaesthetic agents, and performed preference tests using adult mixed sex zebrafish (Danio rerio, the most commonly held laboratory fish. Video tracking software quantified swimming behaviour related to aversion for each anaesthetic at 50% of its standard recommended dose compared with clean water in a flow-through chemotaxic choice chamber. Results suggest that several commonly used anaesthetics were aversive, including two of the most commonly recommended and used: MS222 (ethyl 3-aminobenzoate methanesulphate and benzocaine. For ethical best practice, it is recommended that compounds that are aversive, even at low concentration, should no longer be used routinely for anaesthesia or indeed the first step of humane euthanasia of adult zebrafish. Two agents were found not to induce aversive behavioural responses: etomidate and 2,2,2 tribromoethanol. For the millions of adult zebrafish used in laboratories and breeding worldwide, etomidate appears best suited for future routine humane use.

  18. Development of an Aversive Pavlovian-to-Instrumental Transfer Task in Rat

    Directory of Open Access Journals (Sweden)

    Vincent eCampese

    2013-11-01

    Full Text Available Pavlovian-to-instrumental transfer (PIT is an effect whereby a classically conditioned stimulus (CS enhances ongoing instrumental responding. PIT has been extensively studied with appetitive conditioning but barely at all with aversive conditioning. Although it’s been argued that conditioned suppression is a form of aversive PIT, this effect is fundamentally different from appetitive PIT because the CS suppresses, instead of facilitates, responding. Five experiments investigated the importance of a variety of factors on aversive PIT in a rodent Sidman avoidance paradigm in which ongoing shuttling behavior was facilitated by an aversive CS. Experiment 1 demonstrated a basic PIT effect. Experiment 2 found that a moderate amount of USAA extinction produces the strongest PIT with shuttling rates best at around 2 responses per minute prior to the CS. Experiment 3 tested a protocol in which the USAA behavior was required to reach the 2-response per minute mark in order to trigger the CS presentation and found that this produced robust and reliable PIT. Experiment 4 found that the Pavlovian conditioning US intensity was not a major determinant of PIT strength. Experiment 5 demonstrated that if the CS and US were not explicitly paired during Pavlovian conditioning, PIT did not occur, showing that CS-US learning is required. Together, these studies demonstrate a robust, reliable and stable aversive PIT effect that is amenable to analysis of neural circuitry.

  19. Development of an aversive Pavlovian-to-instrumental transfer task in rat.

    Science.gov (United States)

    Campese, Vincent; McCue, Margaret; Lázaro-Muñoz, Gabriel; Ledoux, Joseph E; Cain, Christopher K

    2013-01-01

    Pavlovian-to-instrumental transfer (PIT) is an effect whereby a classically conditioned stimulus (CS) enhances ongoing instrumental responding. PIT has been extensively studied with appetitive conditioning but barely at all with aversive conditioning. Although it's been argued that conditioned suppression is a form of aversive PIT, this effect is fundamentally different from appetitive PIT because the CS suppresses, instead of facilitates, responding. Five experiments investigated the importance of a variety of factors on aversive PIT in a rodent Sidman avoidance paradigm in which ongoing shuttling behavior (unsignaled active avoidance or USAA) was facilitated by an aversive CS. Experiment 1 demonstrated a basic PIT effect. Experiment 2 found that a moderate amount of USAA extinction produces the strongest PIT with shuttling rates best at around 2 responses per minute prior to the CS. Experiment 3 tested a protocol in which the USAA behavior was required to reach the 2-response per minute mark in order to trigger the CS presentation and found that this produced robust and reliable PIT. Experiment 4 found that the Pavlovian conditioning US intensity was not a major determinant of PIT strength. Experiment 5 demonstrated that if the CS and US were not explicitly paired during Pavlovian conditioning, PIT did not occur, showing that CS-US learning is required. Together, these studies demonstrate a robust, reliable and stable aversive PIT effect that is amenable to analysis of neural circuitry.

  20. Midbrain dopamine neurons signal aversion in a reward-context-dependent manner

    Science.gov (United States)

    Matsumoto, Hideyuki; Tian, Ju; Uchida, Naoshige; Watabe-Uchida, Mitsuko

    2016-01-01

    Dopamine is thought to regulate learning from appetitive and aversive events. Here we examined how optogenetically-identified dopamine neurons in the lateral ventral tegmental area of mice respond to aversive events in different conditions. In low reward contexts, most dopamine neurons were exclusively inhibited by aversive events, and expectation reduced dopamine neurons’ responses to reward and punishment. When a single odor predicted both reward and punishment, dopamine neurons’ responses to that odor reflected the integrated value of both outcomes. Thus, in low reward contexts, dopamine neurons signal value prediction errors (VPEs) integrating information about both reward and aversion in a common currency. In contrast, in high reward contexts, dopamine neurons acquired a short-latency excitation to aversive events that masked their VPE signaling. Our results demonstrate the importance of considering the contexts to examine the representation in dopamine neurons and uncover different modes of dopamine signaling, each of which may be adaptive for different environments. DOI: http://dx.doi.org/10.7554/eLife.17328.001 PMID:27760002

  1. DeepTrack: Learning Discriminative Feature Representations Online for Robust Visual Tracking.

    Science.gov (United States)

    Hanxi Li; Yi Li; Porikli, Fatih

    2016-04-01

    Deep neural networks, albeit their great success on feature learning in various computer vision tasks, are usually considered as impractical for online visual tracking, because they require very long training time and a large number of training samples. In this paper, we present an efficient and very robust tracking algorithm using a single convolutional neural network (CNN) for learning effective feature representations of the target object in a purely online manner. Our contributions are multifold. First, we introduce a novel truncated structural loss function that maintains as many training samples as possible and reduces the risk of tracking error accumulation. Second, we enhance the ordinary stochastic gradient descent approach in CNN training with a robust sample selection mechanism. The sampling mechanism randomly generates positive and negative samples from different temporal distributions, which are generated by taking the temporal relations and label noise into account. Finally, a lazy yet effective updating scheme is designed for CNN training. Equipped with this novel updating algorithm, the CNN model is robust to some long-existing difficulties in visual tracking, such as occlusion or incorrect detections, without loss of the effective adaption for significant appearance changes. In the experiment, our CNN tracker outperforms all compared state-of-the-art methods on two recently proposed benchmarks, which in total involve over 60 video sequences. The remarkable performance improvement over the existing trackers illustrates the superiority of the feature representations, which are learned purely online via the proposed deep learning framework.

  2. The Effect of Visual of a Courseware towards Pre-University Students' Learning in Literature

    Science.gov (United States)

    Masri, Mazyrah; Wan Ahmad, Wan Fatimah; Nordin, Shahrina Md.; Sulaiman, Suziah

    This paper highlights the effect of visual of a multimedia courseware, Black Cat Courseware (BC-C), developed for learning literature at a pre-university level in University Teknologi PETRONAS (UTP). The contents of the courseware are based on a Black Cat story which is covered in an English course at the university. The objective of this paper is to evaluate the usability and effectiveness of BC-C. A total of sixty foundation students were involved in the study. Quasi-experimental design was employed, forming two groups: experimental and control groups. The experimental group had to interact with BC-C as part of the learning activities while the control group used the conventional learning methods. The results indicate that the experimental group achieved a statistically significant compared to the control group in understanding the Black Cat story. The study result also proves that the effect of visual increases the students' performances in literature learning at a pre-university level.

  3. Design of a Braille Learning Application for Visually Impaired Students in Bangladesh.

    Science.gov (United States)

    Nahar, Lutfun; Jaafar, Azizah; Ahamed, Eistiak; Kaish, A B M A

    2015-01-01

    Visually impaired students (VIS) are unable to get visual information, which has made their learning process complicated. This paper discusses the overall situation of VIS in Bangladesh and identifies major challenges that they are facing in getting education. The Braille system is followed to educate blind students in Bangladesh. However, lack of Braille based educational resources and technological solutions have made the learning process lengthy and complicated for VIS. As a developing country, Bangladesh cannot afford for the costly Braille related technological tools for VIS. Therefore, a mobile phone based Braille application, "mBRAILLE", for Android platform is designed to provide an easy Braille learning technology for VIS in Bangladesh. The proposed design is evaluated by experts in assistive technology for students with disabilities, and advanced learners of Braille. The application aims to provide a Bangla and English Braille learning platform for VIS. In this paper, we depict iterative (participatory) design of the application along with a preliminary evaluation with 5 blind subjects, and 1 sighted and 2 blind experts. The results show that the design scored an overall satisfaction level of 4.53 out of 5 by all respondents, indicating that our design is ready for the next step of development.

  4. The 50s cliff: a decline in perceptuo-motor learning, not a deficit in visual motion perception.

    Directory of Open Access Journals (Sweden)

    Jie Ren

    Full Text Available Previously, we measured perceptuo-motor learning rates across the lifespan and found a sudden drop in learning rates between ages 50 and 60, called the "50s cliff." The task was a unimanual visual rhythmic coordination task in which participants used a joystick to oscillate one dot in a display in coordination with another dot oscillated by a computer. Participants learned to produce a coordination with a 90° relative phase relation between the dots. Learning rates for participants over 60 were half those of younger participants. Given existing evidence for visual motion perception deficits in people over 60 and the role of visual motion perception in the coordination task, it remained unclear whether the 50s cliff reflected onset of this deficit or a genuine decline in perceptuo-motor learning. The current work addressed this question. Two groups of 12 participants in each of four age ranges (20s, 50s, 60s, 70s learned to perform a bimanual coordination of 90° relative phase. One group trained with only haptic information and the other group with both haptic and visual information about relative phase. Both groups were tested in both information conditions at baseline and post-test. If the 50s cliff was caused by an age dependent deficit in visual motion perception, then older participants in the visual group should have exhibited less learning than those in the haptic group, which should not exhibit the 50s cliff, and older participants in both groups should have performed less well when tested with visual information. Neither of these expectations was confirmed by the results, so we concluded that the 50s cliff reflects a genuine decline in perceptuo-motor learning with aging, not the onset of a deficit in visual motion perception.

  5. Measuring Learning Styles with Questionnaires versus Direct Observation of Preferential Choice Behavior in Authentic Learning Situations: The Visualizer/Verbalizer Behavior Observation Scale (VV-BOS).

    Science.gov (United States)

    Leutner, Detlev; Plass, Jan L.

    1998-01-01

    Describes the development of the VV-BOS (Visualizer/Verbalizer Behavior Observation Scale), a computer-based instrument for direct observation of students' preferences for visual or verbal learning material. Results of a study with second-language learners indicated a high degree of reliability as an alternative to conventional questionnaires.…

  6. Observing before Learning: Visual Material for the Learning of English as a Foreign Language

    Directory of Open Access Journals (Sweden)

    Diana Benavides

    2009-12-01

    Full Text Available This article is a report of the findings of a research project developed in a Colombian school, Academia La Salle San Benildo, as a requirement for the B.A. degree in Modern Languages at La Salle University. The goal of this project is to describe the impact of working with visual material with the students of fifth and third grades. The data collected throughout the process include an interview, a survey, students’ work, and journals kept by the student teachers. The results of the analysis of the research show the importance of the application of visual material in the teaching process.

  7. Multivoxel Object Representations in Adult Human Visual Cortex Are Flexible: An Associative Learning Study.

    Science.gov (United States)

    Senoussi, Mehdi; Berry, Isabelle; VanRullen, Rufin; Reddy, Leila

    2016-06-01

    Learning associations between co-occurring events enables us to extract structure from our environment. Medial-temporal lobe structures are critical for associative learning. However, the role of the ventral visual pathway (VVP) in associative learning is not clear. Do multivoxel object representations in the VVP reflect newly formed associations? We show that VVP multivoxel representations become more similar to each other after human participants learn arbitrary new associations between pairs of unrelated objects (faces, houses, cars, chairs). Participants were scanned before and after 15 days of associative learning. To evaluate how object representations changed, a classifier was trained on discriminating two nonassociated categories (e.g., faces/houses) and tested on discriminating their paired associates (e.g., cars/chairs). Because the associations were arbitrary and counterbalanced across participants, there was initially no particular reason for this cross-classification decision to tend toward either alternative. Nonetheless, after learning, cross-classification performance increased in the VVP (but not hippocampus), on average by 3.3%, with some voxels showing increases of up to 10%. For example, a chair multivoxel representation that initially resembled neither face nor house representations was, after learning, classified as more similar to that of faces for participants who associated chairs with faces and to that of houses for participants who associated chairs with houses. Additionally, learning produced long-lasting perceptual consequences. In a behavioral priming experiment performed several months later, the change in cross-classification performance was correlated with the degree of priming. Thus, VVP multivoxel representations are not static but become more similar to each other after associative learning.

  8. Learning enhances the relative impact of top-down processing in the visual cortex.

    Science.gov (United States)

    Makino, Hiroshi; Komiyama, Takaki

    2015-08-01

    Theories have proposed that, in sensory cortices, learning can enhance top-down modulation by higher brain areas while reducing bottom-up sensory drives. To address circuit mechanisms underlying this process, we examined the activity of layer 2/3 (L2/3) excitatory neurons in the mouse primary visual cortex (V1) as well as L4 excitatory neurons, the main bottom-up source, and long-range top-down projections from the retrosplenial cortex (RSC) during associative learning over days using chronic two-photon calcium imaging. During learning, L4 responses gradually weakened, whereas RSC inputs became stronger. Furthermore, L2/3 acquired a ramp-up response temporal profile, potentially encoding the timing of the associated event, which coincided with a similar change in RSC inputs. Learning also reduced the activity of somatostatin-expressing inhibitory neurons (SOM-INs) in V1 that could potentially gate top-down inputs. Finally, RSC inactivation or SOM-IN activation was sufficient to partially reverse the learning-induced changes in L2/3. Together, these results reveal a learning-dependent dynamic shift in the balance between bottom-up and top-down information streams and uncover a role of SOM-INs in controlling this process.

  9. Social learning of predators in the dark: understanding the role of visual, chemical and mechanical information.

    Science.gov (United States)

    Manassa, R P; McCormick, M I; Chivers, D P; Ferrari, M C O

    2013-08-22

    The ability of prey to observe and learn to recognize potential predators from the behaviour of nearby individuals can dramatically increase survival and, not surprisingly, is widespread across animal taxa. A range of sensory modalities are available for this learning, with visual and chemical cues being well-established modes of transmission in aquatic systems. The use of other sensory cues in mediating social learning in fishes, including mechano-sensory cues, remains unexplored. Here, we examine the role of different sensory cues in social learning of predator recognition, using juvenile damselfish (Amphiprion percula). Specifically, we show that a predator-naive observer can socially learn to recognize a novel predator when paired with a predator-experienced conspecific in total darkness. Furthermore, this study demonstrates that when threatened, individuals release chemical cues (known as disturbance cues) into the water. These cues induce an anti-predator response in nearby individuals; however, they do not facilitate learnt recognition of the predator. As such, another sensory modality, probably mechano-sensory in origin, is responsible for information transfer in the dark. This study highlights the diversity of sensory cues used by coral reef fishes in a social learning context.

  10. Concurrent recall of serially learned visual discrimination problems in dwarf goats (Capra hircus).

    Science.gov (United States)

    Langbein, J; Siebert, K; Nuernberg, G

    2008-11-01

    Studies of cognitive ability in farm animals are valuable, not only because they provide indicators of the commonality of comparative influence, but understanding farm animal cognition may also aid in management and treatment procedures. Here, eight dwarf goats (Capra hircus) learned a series of 10 visual four-choice discriminations using an automated device that allowed individual ad lib. access to the test setup while staying in a familiar environment and normal social setting. The animals were trained on each problem for 5 days, followed by concurrent testing of the current against the previous problem. Once all 10 problems had been learned, they were tested concurrently over the course of 9 days. In initial training, all goats achieved criterion learning levels on nearly all problems within 2 days and under 200 trials. Concurrently presenting the problems trained in adjacent sessions did not impair performance on either problem relative to single-problem learning. Upon concurrent presentation of all 10 previously learned problems, at least half were well-remembered immediately. Although this test revealed a recency effect (later problems were better remembered), many early-learned problems were also well-retained, and 10-item relearning was quite quick. These results show that dwarf goats can retain multiple-problem information proficiently and can do so over periods of several weeks. From an ecological point of view, the ability to form numerous associations between visual cues offered by specific plants and food quality is an important pre-grazing mechanism that helps goats exploit variation in vegetation and graze selectively.

  11. Effects of Anodal Transcranial Direct Current Stimulation on Visually Guided Learning of Grip Force Control

    Directory of Open Access Journals (Sweden)

    Tamas Minarik

    2015-03-01

    Full Text Available Anodal transcranial Direct Current Stimulation (tDCS has been shown to be an effective non-invasive brain stimulation method for improving cognitive and motor functioning in patients with neurological deficits. tDCS over motor cortex (M1, for instance, facilitates motor learning in stroke patients. However, the literature on anodal tDCS effects on motor learning in healthy participants is inconclusive, and the effects of tDCS on visuo-motor integration are not well understood. In the present study we examined whether tDCS over the contralateral motor cortex enhances learning of grip-force output in a visually guided feedback task in young and neurologically healthy volunteers. Twenty minutes of 1 mA anodal tDCS were applied over the primary motor cortex (M1 contralateral to the dominant (right hand, during the first half of a 40 min power-grip task. This task required the control of a visual signal by modulating the strength of the power-grip for six seconds per trial. Each participant completed a two-session sham-controlled crossover protocol. The stimulation conditions were counterbalanced across participants and the sessions were one week apart. Performance measures comprised time-on-target and target-deviation, and were calculated for the periods of stimulation (or sham and during the afterphase respectively. Statistical analyses revealed significant performance improvements over the stimulation and the afterphase, but this learning effect was not modulated by tDCS condition. This suggests that the form of visuomotor learning taking place in the present task was not sensitive to neurostimulation. These null effects, together with similar reports for other types of motor tasks, lead to the proposition that tDCS facilitation of motor learning might be restricted to cases or situations where the motor system is challenged, such as motor deficits, advanced age, or very high task demand.

  12. Risk Aversion, Intergenerational Equity and Climate Change

    Energy Technology Data Exchange (ETDEWEB)

    Ha-Duong, Minh [CNRS-CIRED, Paris (France); Treich, N. [LEERNA-INRA, University of Toulouse (France)

    2004-06-01

    The paper investigates a climate-economy model with an iso-elastic welfare function in which one parameter {gamma} measures relative risk-aversion and a distinct parameter {rho} measures resistance to intertemporal substitution. We show both theoretically and numerically that climate policy responds differently to variations in the two parameters. In particular, we show that higher {gamma} but lower {rho} leads to increase emissions control. We also argue that climate-economy models based on intertemporal expected utility maximization, i.e. models where {gamma} ={rho}, may misinterpret the sensitivity of the climate policy to risk-aversion.

  13. Individual personality differences in goats predict their performance in visual learning and non-associative cognitive tasks.

    Science.gov (United States)

    Nawroth, Christian; Prentice, Pamela M; McElligott, Alan G

    2017-01-01

    Variation in common personality traits, such as boldness or exploration, is often associated with risk-reward trade-offs and behavioural flexibility. To date, only a few studies have examined the effects of consistent behavioural traits on both learning and cognition. We investigated whether certain personality traits ('exploration' and 'sociability') of individuals were related to cognitive performance, learning flexibility and learning style in a social ungulate species, the goat (Capra hircus). We also investigated whether a preference for feature cues rather than impaired learning abilities can explain performance variation in a visual discrimination task. We found that personality scores were consistent across time and context. Less explorative goats performed better in a non-associative cognitive task, in which subjects had to follow the trajectory of a hidden object (i.e. testing their ability for object permanence). We also found that less sociable subjects performed better compared to more sociable goats in a visual discrimination task. Good visual learning performance was associated with a preference for feature cues, indicating personality-dependent learning strategies in goats. Our results suggest that personality traits predict the outcome in visual discrimination and non-associative cognitive tasks in goats and that impaired performance in a visual discrimination tasks does not necessarily imply impaired learning capacities, but rather can be explained by a varying preference for feature cues.

  14. Effects of visual feedback-induced variability on motor learning of handrim wheelchair propulsion.

    Directory of Open Access Journals (Sweden)

    Marika T Leving

    Full Text Available It has been suggested that a higher intra-individual variability benefits the motor learning of wheelchair propulsion. The present study evaluated whether feedback-induced variability on wheelchair propulsion technique variables would also enhance the motor learning process. Learning was operationalized as an improvement in mechanical efficiency and propulsion technique, which are thought to be closely related during the learning process.17 Participants received visual feedback-based practice (feedback group and 15 participants received regular practice (natural learning group. Both groups received equal practice dose of 80 min, over 3 weeks, at 0.24 W/kg at a treadmill speed of 1.11 m/s. To compare both groups the pre- and post-test were performed without feedback. The feedback group received real-time visual feedback on seven propulsion variables with instruction to manipulate the presented variable to achieve the highest possible variability (1st 4-min block and optimize it in the prescribed direction (2nd 4-min block. To increase motor exploration the participants were unaware of the exact variable they received feedback on. Energy consumption and the propulsion technique variables with their respective coefficient of variation were calculated to evaluate the amount of intra-individual variability.The feedback group, which practiced with higher intra-individual variability, improved the propulsion technique between pre- and post-test to the same extent as the natural learning group. Mechanical efficiency improved between pre- and post-test in the natural learning group but remained unchanged in the feedback group.These results suggest that feedback-induced variability inhibited the improvement in mechanical efficiency. Moreover, since both groups improved propulsion technique but only the natural learning group improved mechanical efficiency, it can be concluded that the improvement in mechanical efficiency and propulsion technique do not

  15. Multisensory aversive stimuli differentially modulate negative feelings in near and far space.

    Science.gov (United States)

    Taffou, Marine; Ondřej, Jan; O'Sullivan, Carol; Warusfel, Olivier; Dubal, Stéphanie; Viaud-Delmon, Isabelle

    2016-05-05

    Affect, space, and multisensory integration are processes that are closely linked. However, it is unclear whether the spatial location of emotional stimuli interacts with multisensory presentation to influence the emotional experience they induce in the perceiver. In this study, we used the unique advantages of virtual reality techniques to present potentially aversive crowd stimuli embedded in a natural context and to control their display in terms of sensory and spatial presentation. Individuals high in crowdphobic fear navigated in an auditory-visual virtual environment, in which they encountered virtual crowds presented through the visual channel, the auditory channel, or both. They reported the intensity of their negative emotional experience at a far distance and at a close distance from the crowd stimuli. Whereas auditory-visual presentation of close feared stimuli amplified negative feelings, auditory-visual presentation of distant feared stimuli did not amplify negative feelings. This suggests that spatial closeness allows multisensory processes to modulate the intensity of the emotional experience induced by aversive stimuli. Nevertheless, the specific role of auditory stimulation must be investigated to better understand this interaction between multisensory, affective, and spatial representation processes. This phenomenon may serve the implementation of defensive behaviors in response to aversive stimuli that are in position to threaten an individual's feeling of security.

  16. Learning-Based Visual Saliency Model for Detecting Diabetic Macular Edema in Retinal Image.

    Science.gov (United States)

    Zou, Xiaochun; Zhao, Xinbo; Yang, Yongjia; Li, Na

    2016-01-01

    This paper brings forth a learning-based visual saliency model method for detecting diagnostic diabetic macular edema (DME) regions of interest (RoIs) in retinal image. The method introduces the cognitive process of visual selection of relevant regions that arises during an ophthalmologist's image examination. To record the process, we collected eye-tracking data of 10 ophthalmologists on 100 images and used this database as training and testing examples. Based on analysis, two properties (Feature Property and Position Property) can be derived and combined by a simple intersection operation to obtain a saliency map. The Feature Property is implemented by support vector machine (SVM) technique using the diagnosis as supervisor; Position Property is implemented by statistical analysis of training samples. This technique is able to learn the preferences of ophthalmologist visual behavior while simultaneously considering feature uniqueness. The method was evaluated using three popular saliency model evaluation scores (AUC, EMD, and SS) and three quality measurements (classical sensitivity, specificity, and Youden's J statistic). The proposed method outperforms 8 state-of-the-art saliency models and 3 salient region detection approaches devised for natural images. Furthermore, our model successfully detects the DME RoIs in retinal image without sophisticated image processing such as region segmentation.

  17. Spatial Visualization Tasks To Support Students’ Spatial Structuring In Learning Volume Measurement

    Directory of Open Access Journals (Sweden)

    Shintia Revina

    2011-07-01

    Full Text Available Many prior researches found that most of students in grade five tended to have difficulty in fully grasping the concept of volume measurement because they have to build their competence in spatial structuring. The unit of volume “packing” measurement must be integrated and coordinated in three-dimension. On the other hand, it is revealed the errors that students made on the volume measurement tasks with threedimensional cube arrays are related to some aspects of spatial visualization, such as the skill to "read off" two-dimensional representation of solid objects. For those reasons, this research is aimed to develop classroom activities with the use of spatial visualization tasks to support students’ spatial structuring in learning volume measurement. Consequently, design research was chosen as an appropriate means to achieve this research goal. In this research, a sequence of instructional activities is designed and developed based on the hypothesis of students’ learning processes. This research was conducted in grade 5 of SD Pupuk Sriwijaya Palembang, Indonesia.Keywords: volume measurement, spatial structuring, spatial visualization, design research. DOI: http://dx.doi.org/10.22342/jme.2.2.745.127-146

  18. Observation of Depictive Versus Tracing Gestures Selectively Aids Verbal Versus Visual-Spatial Learning in Primary School Children

    NARCIS (Netherlands)

    van Wermeskerken, Margot; Fijan, Nathalie; Eielts, Charly; Pouw, Wim T. J. L.

    2016-01-01

    Previous research has established that gesture observation aids learning in children. The current study examined whether observation of gestures (i.e. depictive and tracing gestures) differentially affected verbal and visual-spatial retention when learning a route and its street names. Specifically,

  19. The Effect of Using a Visual Representation Tool in a Teaching-Learning Sequence for Teaching Newton's Third Law

    Science.gov (United States)

    Savinainen, Antti; Mäkynen, Asko; Nieminen, Pasi; Viiri, Jouni

    2017-01-01

    This paper presents a research-based teaching-learning sequence (TLS) that focuses on the notion of interaction in teaching Newton's third law (N3 law) which is, as earlier studies have shown, a challenging topic for students to learn. The TLS made systematic use of a visual representation tool--an interaction diagram (ID)--highlighting…

  20. Teaching with Concrete and Abstract Visual Representations: Effects on Students' Problem Solving, Problem Representations, and Learning Perceptions

    Science.gov (United States)

    Moreno, Roxana; Ozogul, Gamze; Reisslein, Martin

    2011-01-01

    In 3 experiments, we examined the effects of using concrete and/or abstract visual problem representations during instruction on students' problem-solving practice, near transfer, problem representations, and learning perceptions. In Experiments 1 and 2, novice students learned about electrical circuit analysis with an instructional program that…

  1. Visual Recognition by Learning From Web Data via Weakly Supervised Domain Generalization.

    Science.gov (United States)

    Niu, Li; Li, Wen; Xu, Dong; Cai, Jianfei

    2016-06-01

    In this paper, a weakly supervised domain generalization (WSDG) method is proposed for real-world visual recognition tasks, in which we train classifiers by using Web data (\\eg, Web images and Web videos) with noisy labels. In particular, two challenging problems need to be solved when learning robust classifiers, in which the first issue is to cope with the label noise of training Web data from the source domain, while the second issue is to enhance the generalization capability of learned classifiers to an arbitrary target domain. In order to handle the first problem, the training samples within each category are partitioned into clusters, where we use one bag to denote each cluster and instances to denote the samples in each cluster. Then, we identify a proportion of good training samples in each bag and train robust classifiers by using the good training samples, which leads to a multi-instance learning (MIL) problem. In order to handle the second problem, we assume that the training samples possibly form a set of hidden domains, with each hidden domain associated with a distinctive data distribution. Then, for each category and each hidden latent domain, we propose to learn one classifier by extending our MIL formulation, which leads to our WSDG approach. In the testing stage, our approach can obtain better generalization capability by effectively integrating multiple classifiers from different latent domains in each category. Moreover, our WSDG approach is further extended to utilize additional textual descriptions associated with Web data as privileged information (PI), although testing data do not have such PI. Extensive experiments on three benchmark data sets indicate that our newly proposed methods are effective for real-world visual recognition tasks by learning from Web data.

  2. Enhancing the T-shaped learning profile when teaching hydrology using data, modeling, and visualization activities

    Science.gov (United States)

    Sanchez, Christopher A.; Ruddell, Benjamin L.; Schiesser, Roy; Merwade, Venkatesh

    2016-03-01

    Previous research has suggested that the use of more authentic learning activities can produce more robust and durable knowledge gains. This is consistent with calls within civil engineering education, specifically hydrology, that suggest that curricula should more often include professional perspective and data analysis skills to better develop the "T-shaped" knowledge profile of a professional hydrologist (i.e., professional breadth combined with technical depth). It was expected that the inclusion of a data-driven simulation lab exercise that was contextualized within a real-world situation and more consistent with the job duties of a professional in the field, would provide enhanced learning and appreciation of job duties beyond more conventional paper-and-pencil exercises in a lower-division undergraduate course. Results indicate that while students learned in both conditions, learning was enhanced for the data-driven simulation group in nearly every content area. This pattern of results suggests that the use of data-driven modeling and visualization activities can have a significant positive impact on instruction. This increase in learning likely facilitates the development of student perspective and conceptual mastery, enabling students to make better choices about their studies, while also better preparing them for work as a professional in the field.

  3. Adjustment to Subtle Time Constraints and Power Law Learning in Rapid Serial Visual Presentation.

    Science.gov (United States)

    Shin, Jacqueline C; Chang, Seah; Cho, Yang Seok

    2015-01-01

    We investigated whether attention could be modulated through the implicit learning of temporal information in a rapid serial visual presentation (RSVP) task. Participants identified two target letters among numeral distractors. The stimulus-onset asynchrony immediately following the first target (SOA1) varied at three levels (70, 98, and 126 ms) randomly between trials or fixed within blocks of trials. Practice over 3 consecutive days resulted in a continuous improvement in the identification rate for both targets and attenuation of the attentional blink (AB), a decrement in target (T2) identification when presented 200-400 ms after another target (T1). Blocked SOA1s led to a faster rate of improvement in RSVP performance and more target order reversals relative to random SOA1s, suggesting that the implicit learning of SOA1 positively affected performance. The results also reveal "power law" learning curves for individual target identification as well as the reduction in the AB decrement. These learning curves reflect the spontaneous emergence of skill through subtle attentional modulations rather than general attentional distribution. Together, the results indicate that implicit temporal learning could improve high level and rapid cognitive processing and highlights the sensitivity and adaptability of the attentional system to subtle constraints in stimulus timing.

  4. Deep Learning Guided Partitioned Shape Model for Anterior Visual Pathway Segmentation.

    Science.gov (United States)

    Mansoor, Awais; Cerrolaza, Juan J; Idrees, Rabia; Biggs, Elijah; Alsharid, Mohammad A; Avery, Robert A; Linguraru, Marius George

    2016-08-01

    Analysis of cranial nerve systems, such as the anterior visual pathway (AVP), from MRI sequences is challenging due to their thin long architecture, structural variations along the path, and low contrast with adjacent anatomic structures. Segmentation of a pathologic AVP (e.g., with low-grade gliomas) poses additional challenges. In this work, we propose a fully automated partitioned shape model segmentation mechanism for AVP steered by multiple MRI sequences and deep learning features. Employing deep learning feature representation, this framework presents a joint partitioned statistical shape model able to deal with healthy and pathological AVP. The deep learning assistance is particularly useful in the poor contrast regions, such as optic tracts and pathological areas. Our main contributions are: 1) a fast and robust shape localization method using conditional space deep learning, 2) a volumetric multiscale curvelet transform-based intensity normalization method for robust statistical model, and 3) optimally partitioned statistical shape and appearance models based on regional shape variations for greater local flexibility. Our method was evaluated on MRI sequences obtained from 165 pediatric subjects. A mean Dice similarity coefficient of 0.779 was obtained for the segmentation of the entire AVP (optic nerve only =0.791 ) using the leave-one-out validation. Results demonstrated that the proposed localized shape and sparse appearance-based learning approach significantly outperforms current state-of-the-art segmentation approaches and is as robust as the manual segmentation.

  5. Adjustment to subtle time constraints and power law learning in rapid serial visual presentation

    Directory of Open Access Journals (Sweden)

    Jacqueline Chakyung Shin

    2015-11-01

    Full Text Available We investigated whether attention could be modulated through the implicit learning of temporal information in a rapid serial visual presentation (RSVP task. Participants identified two target letters among numeral distractors. The stimulus-onset asynchrony immediately following the first target (SOA1 varied at three levels (70, 98, and 126 ms randomly between trials or fixed within blocks of trials. Practice over three consecutive days resulted in a continuous improvement in the identification rate for both targets and attenuation of the attentional blink (AB, a decrement in target (T2 identification when presented 200-400 ms after another target (T1. Blocked SOA1s led to a faster rate of improvement in RSVP performance and more target order reversals relative to random SOA1s, suggesting that the implicit learning of SOA1 positively affected performance. The results also reveal power law learning curves for individual target identification as well as the reduction in the AB decrement. These learning curves reflect the spontaneous emergence of skill through subtle attentional modulations rather than general attentional distribution. Together, the results indicate that implicit temporal learning could improve high level and rapid cognitive processing and highlights the sensitivity and adaptability of the attentional system to subtle constraints in stimulus timing.

  6. Side effects of being blue: influence of sad mood on visual statistical learning.

    Directory of Open Access Journals (Sweden)

    Julie Bertels

    Full Text Available It is well established that mood influences many cognitive processes, such as learning and executive functions. Although statistical learning is assumed to be part of our daily life, as mood does, the influence of mood on statistical learning has never been investigated before. In the present study, a sad vs. neutral mood was induced to the participants through the listening of stories while they were exposed to a stream of visual shapes made up of the repeated presentation of four triplets, namely sequences of three shapes presented in a fixed order. Given that the inter-stimulus interval was held constant within and between triplets, the only cues available for triplet segmentation were the transitional probabilities between shapes. Direct and indirect measures of learning taken either immediately or 20 minutes after the exposure/mood induction phase revealed that participants learned the statistical regularities between shapes. Interestingly, although participants from the sad and neutral groups performed similarly in these tasks, subjective measures (confidence judgments taken after each trial revealed that participants who experienced the sad mood induction showed increased conscious access to their statistical knowledge. These effects were not modulated by the time delay between the exposure/mood induction and the test phases. These results are discussed within the scope of the robustness principle and the influence of negative affects on processing style.

  7. Visual Literacy Skills of Students in College-Level Biology: Learning Outcomes following Digital or Hand-Drawing Activities

    Directory of Open Access Journals (Sweden)

    Justine C. Bell

    2014-11-01

    Full Text Available To test the claim that digital learning tools enhance the acquisition of visual literacy in this generation of biology students, a learning intervention was carried out with 33 students enrolled in an introductory college biology course. This study compared learning outcomes following two types of learning tools: a traditional drawing activity, or a learning activity on a computer. The sample was divided into two random groups. In the first intervention students learned how to draw and label a cell. Group 1 learned the material by computer and Group 2 learned the material by hand drawing. In the second intervention, students learned how to draw the phases of mitosis, and the two groups were inverted. After each learning activity, students were given a quiz, and were also asked to self-evaluate their performance in an attempt to measure their level of metacognition. At the end of the study, participants were asked to fill out a questionnaire that was used to measure the level of task engagement the students felt towards the two types of learning activities. The students who learned the material by drawing had a significantly higher average grade on the associated quiz compared to that of those who learned the material by computer. There were no other significant differences in learning outcomes between the two groups. This study provides evidence that drawing by hand is beneficial for learning biological images compared to learning the same material on a computer.

  8. Pharmacological aversion treatment of alcohol dependence. I. Production and prediction of conditioned alcohol aversion.

    Science.gov (United States)

    Howard, M O

    2001-08-01

    Eighty-two hospitalized alcoholics receiving pharmacological aversion therapy (PAT) over a 10-day treatment interval completed cognitive, behavioral, and psychophysiological measures evaluating conditioned aversion to alcohol. Pre-post assessments provided convergent support for the efficacy of PAT vis-à-vis production of conditioned aversion to alcohol. Positive alcohol-related outcome expectancies were significantly reduced, whereas confidence that drinking could be avoided in various high-risk situations for consumption was increased following PAT. Behavioral and cardiac rate assessments revealed significant changes following PAT that were specific to alcoholic beverages and potentially reflective of conditioned alcohol aversion. Patients with more extensive pretreatment experiences with alcohol-associated nausea and greater involvement in antisocial conduct appeared to be less susceptible to the PAT conditioning protocol.

  9. Household portfolios and implicit risk aversion

    NARCIS (Netherlands)

    Bucciol, A.; Miniaci, R.

    2008-01-01

    We derive from a sample of US households the distribution of the risk aversion implicit in their portfolio choice. Our estimate minimizes the distance between the certainty equivalent return generated with observed portfolios and portfolios that are optimal in a mean-variance framework. Taking into

  10. Public Sector Employees: Risk Averse and Altruistic?

    NARCIS (Netherlands)

    M.W.J.M. Buurman (Margaretha); A.J. Dur (Robert); S. Bossche, van den (Seth)

    2009-01-01

    textabstractWe assess whether public sector employees have a stronger inclination to serve others and are more risk averse than employees in the private sector. A unique feature of our study is that we use revealed rather than stated preferences data. Respondents of a large-scale survey were offered

  11. Public sector employees: risk averse and altruistic?

    NARCIS (Netherlands)

    Buurman, M.; Delfgaauw, J.; Dur, R.; Bossche, S.N.J. van den

    2012-01-01

    We assess whether public sector employees have a stronger inclination to serve others and are more risk averse than employees in the private sector. A unique feature of our study is that we use revealed rather than stated preferences data. Respondents of a large-scale survey were offered a substanti

  12. Public sector employees: risk averse and altruistic?

    NARCIS (Netherlands)

    Buurman, M.; Dur, R.; Bossche, S.N.J. van den

    2009-01-01

    We assess whether public sector employees have a stronger inclination to serve others and are more risk averse than employees in the private sector. A unique feature of our study is that we use revealed rather than stated preferences data. Respondents of a large-scale survey were offered a substanti

  13. On Loss Aversion in Capuchin Monkeys

    Science.gov (United States)

    Silberberg, Alan; Roma, Peter G.; Huntsberry, Mary E.; Warren-Boulton, Frederick R.; Sakagami, Takayuki; Ruggiero, Angela M.; Suomi, Stephen J.

    2008-01-01

    Chen, Lakshminarayanan, and Santos (2006) claim to show in three choice experiments that monkeys react rationally to price and wealth shocks, but, when faced with gambles, display hallmark, human-like biases that include loss aversion. We present three experiments with monkeys and humans consistent with a reinterpretation of their data that…

  14. Random queues and risk averse users

    DEFF Research Database (Denmark)

    de Palma, André; Fosgerau, Mogens

    2013-01-01

    We analyze Nash equilibrium in time of use of a congested facility. Users are risk averse with general concave utility. Queues are subject to varying degrees of random sorting, ranging from strict queue priority to a completely random queue. We define the key “no residual queue” property, which...

  15. Night-Time Vehicle Detection Algorithm Based on Visual Saliency and Deep Learning

    Directory of Open Access Journals (Sweden)

    Yingfeng Cai

    2016-01-01

    Full Text Available Night vision systems get more and more attention in the field of automotive active safety field. In this area, a number of researchers have proposed far-infrared sensor based night-time vehicle detection algorithm. However, existing algorithms have low performance in some indicators such as the detection rate and processing time. To solve this problem, we propose a far-infrared image vehicle detection algorithm based on visual saliency and deep learning. Firstly, most of the nonvehicle pixels will be removed with visual saliency computation. Then, vehicle candidate will be generated by using prior information such as camera parameters and vehicle size. Finally, classifier trained with deep belief networks will be applied to verify the candidates generated in last step. The proposed algorithm is tested in around 6000 images and achieves detection rate of 92.3% and processing time of 25 Hz which is better than existing methods.

  16. Updating temporal expectancy of an aversive event engages striatal plasticity under amygdala control

    Science.gov (United States)

    Dallérac, Glenn; Graupner, Michael; Knippenberg, Jeroen; Martinez, Raquel Chacon Ruiz; Tavares, Tatiane Ferreira; Tallot, Lucille; El Massioui, Nicole; Verschueren, Anna; Höhn, Sophie; Bertolus, Julie Boulanger; Reyes, Alex; LeDoux, Joseph E.; Schafe, Glenn E.; Diaz-Mataix, Lorenzo; Doyère, Valérie

    2017-01-01

    Pavlovian aversive conditioning requires learning of the association between a conditioned stimulus (CS) and an unconditioned, aversive stimulus (US) but also involves encoding the time interval between the two stimuli. The neurobiological bases of this time interval learning are unknown. Here, we show that in rats, the dorsal striatum and basal amygdala belong to a common functional network underlying temporal expectancy and learning of a CS–US interval. Importantly, changes in coherence between striatum and amygdala local field potentials (LFPs) were found to couple these structures during interval estimation within the lower range of the theta rhythm (3–6 Hz). Strikingly, we also show that a change to the CS–US time interval results in long-term changes in cortico-striatal synaptic efficacy under the control of the amygdala. Collectively, this study reveals physiological correlates of plasticity mechanisms of interval timing that take place in the striatum and are regulated by the amygdala. PMID:28067224

  17. CONTROLLING STUDENT RESPONSES DURING VISUAL PRESENTATIONS--STUDIES IN TELEVISED INSTRUCTION, THE ROLE OF VISUALS IN VERBAL LEARNING, REPORT 2.

    Science.gov (United States)

    GROPPER, GEORGE L.

    THIS IS A REPORT OF TWO STUDIES IN WHICH PRINCIPLES OF PROGRAMED INSTRUCTION WERE ADAPTED FOR VISUAL PRESENTATIONS. SCIENTIFIC DEMONSTRATIONS WERE PREPARED WITH A VISUAL PROGRAM AND A VERBAL PROGRAM ON--(1) ARCHIMEDES' LAW AND (2) FORCE AND PRESSURE. RESULTS SUGGESTED THAT RESPONSES ARE MORE READILY BROUGHT UNDER THE CONTROL OF VISUAL PRESENTATION…

  18. Visual statistical learning is related to natural language ability in adults: An ERP study.

    Science.gov (United States)

    Daltrozzo, Jerome; Emerson, Samantha N; Deocampo, Joanne; Singh, Sonia; Freggens, Marjorie; Branum-Martin, Lee; Conway, Christopher M

    2017-03-01

    Statistical learning (SL) is believed to enable language acquisition by allowing individuals to learn regularities within linguistic input. However, neural evidence supporting a direct relationship between SL and language ability is scarce. We investigated whether there are associations between event-related potential (ERP) correlates of SL and language abilities while controlling for the general level of selective attention. Seventeen adults completed tests of visual SL, receptive vocabulary, grammatical ability, and sentence completion. Response times and ERPs showed that SL is related to receptive vocabulary and grammatical ability. ERPs indicated that the relationship between SL and grammatical ability was independent of attention while the association between SL and receptive vocabulary depended on attention. The implications of these dissociative relationships in terms of underlying mechanisms of SL and language are discussed. These results further elucidate the cognitive nature of the links between SL mechanisms and language abilities.

  19. CONTINUOUS EVALUATION OF THE LITERACY AND LEARNING MEDIA OF STUDENTS WITH VISUAL IMPAIRMENT

    Directory of Open Access Journals (Sweden)

    Renata T. PANDUREVIKJ

    2012-09-01

    Full Text Available INTRODUCTION: The procedure for determining an adequate literacy and learning method among students with visual impairments consists two components: an initial choice of mode of literacy, to be conducted during the early childhood and continuing evaluation of the literacy and learning method, which is carried out over students who have already been involved in the educational process for a certain period and with whom a mediums for literacy and learning has already been determined.PURPOSE: The purpose of this research is to conduct a re-evaluation of the initial decision regarding the choice of media through which education is conducted among students with visual impairment.DISCUSSION: The speed of reading is substantially below the predicted minimum level both with students who read Braille and with students who read regular print. It should be mentioned that only 3 respondents out of 15 Braille readers were cooperative in this part of the research, so they obtained results regarding them should not be taken as reliable ones. 100% of the respondents who are educated using the Braille alphabet independently read unfamiliar formal and also familiar educational material. Among the students who use regular print, 62.5% read independently and the other 37.5% need additional instruction. 45.5% of them successfully completed their school assignments using their initially chosen medium for literacy and learning, but only 18.2% of them do it in an acceptable time period. 53.6% of respondents know how to use available resources and facilities that exist within the school, while the other 46, 4% need additional training and instructions.CONCLUSION: Continuous evaluation should be implemented consistently throughout the schooling of the child, or at least once a year, for a relevant "justification" for any change, addition or selection of another sensory channel for learning and literacy of the child, as a result of certain changes in visual functioning of

  20. On-the-fly learning for visual search of large-scale image and video datasets.

    Science.gov (United States)

    Chatfield, Ken; Arandjelović, Relja; Parkhi, Omkar; Zisserman, Andrew

    The objective of this work is to visually search large-scale video datasets for semantic entities specified by a text query. The paradigm we explore is constructing visual models for such semantic entities on-the-fly, i.e. at run time, by using an image search engine to source visual training data for the text query. The approach combines fast and accurate learning and retrieval, and enables videos to be returned within seconds of specifying a query. We describe three classes of queries, each with its associated visual search method: object instances (using a bag of visual words approach for matching); object categories (using a discriminative classifier for ranking key frames); and faces (using a discriminative classifier for ranking face tracks). We discuss the features suitable for each class of query, for example Fisher vectors or features derived from convolutional neural networks (CNNs), and how these choices impact on the trade-off between three important performance measures for a real-time system of this kind, namely: (1) accuracy, (2) memory footprint, and (3) speed. We also discuss and compare a number of important implementation issues, such as how to remove 'outliers' in the downloaded images efficiently, and how to best obtain a single descriptor for a face track. We also sketch the architecture of the real-time on-the-fly system. Quantitative results are given on a number of large-scale image and video benchmarks (e.g.  TRECVID INS, MIRFLICKR-1M), and we further demonstrate the performance and real-world applicability of our methods over a dataset sourced from 10,000 h of unedited footage from BBC News, comprising 5M+ key frames.

  1. Multivariate Gradient Analysis for Evaluating and Visualizing a Learning System Platform for Computer Programming

    Directory of Open Access Journals (Sweden)

    Richard Mather

    2015-02-01

    Full Text Available This paper explores the application of canonical gradient analysis to evaluate and visualize student performance and acceptance of a learning system platform. The subject of evaluation is a first year BSc module for computer programming. This uses ‘Ceebot’, an animated and immersive game-like development environment. Multivariate ordination approaches are widely used in ecology to explore species distribution along environmental gradients. Environmental factors are represented here by three ‘assessment’ gradients; one for the overall module mark and two independent tests of programming knowledge and skill. Response data included Likert expressions for behavioral, acceptance and opinion traits. Behavioral characteristics (such as attendance, collaboration and independent study were regarded to be indicative of learning activity. Acceptance and opinion factors (such as perceived enjoyment and effectiveness of Ceebot were treated as expressions of motivation to engage with the learning environment. Ordination diagrams and summary statistics for canonical analyses suggested that logbook grades (the basis for module assessment and code understanding were weakly correlated. Thus strong module performance was not a reliable predictor of programming ability. The three assessment indices were correlated with behaviors of independent study and peer collaboration, but were only weakly associated with attendance. Results were useful for informing teaching practice and suggested: (1 realigning assessments to more fully capture code-level skills (important in the workplace; (2 re-evaluating attendance-based elements of module design; and (3 the overall merit of multivariate canonical gradient approaches for evaluating and visualizing the effectiveness of a learning system platform.

  2. Perceptual learning for treating amblyopia in children based on activation of visual signal pathway Relationship of curative effects and time

    Institute of Scientific and Technical Information of China (English)

    Weimin Liu; Jiang Shen; Jianzhong Huang; Yan Luo; Hongting Liu

    2008-01-01

    BACKGROUND: Conventional methods (such as occlusion therapy, fine manipulation, complementary, and alternative medicine) take effects slowly, are time and labor consuming, and have uncertain curative effects in the treatment of amblyopia. Perceptual learning, a new method for treating amblyopia, improves the ability to process signals from the cerebral optic nerve system by specific visual stimulation and visual learning, as well as activation of the visual signal pathway utilizing brain nervous system plasticity.OBJECTIVE: This study investigated and evaluated the curative effects of perceptual learning, which can directionally increase brain plasticity, on the treatment of amblyopia in children. The relationship between curative effect and time was also analyzed.DESIGN: A self-control experiment. SETTING: Visual Science and Optometry Center, People's Hospital of Guangxi Zhuang Autonomous Region. PARTICIPANTS: A total of 125 amblyopic children (250 amblyopic eyes), 73 males, 52 females, averaging (6 ± 2) years of age, received treatment at the Visual Science and Optometry Center, People's Hospital of Guangxi Zhuang Autonomous Region between September 2006 and February 2007 and were recruited for this study. All children presented with no structural disease of the eyeballs. Written informed consent for therapeutic regiments was obtained from each child's parent. The protocol received approval from the Hospital's Ethics Committee. METHODS: Visual function was tested with a perceptual learning system (Research Center for Human Health and Development of Sun Yat-sen University, National Engineering Technique Research Center for Medical Care Implement) for visual noise, position noise, contour discrimination, contrast sensitivity, grating stereogram, and random-dot fusion. These tests helped to evaluate the efficiency of visual information processing of these children, and to determine the degree of defects of the optic nerve cells and the connections of visual

  3. Male and female guppies differ in speed but not in accuracy in visual discrimination learning.

    Science.gov (United States)

    Lucon-Xiccato, Tyrone; Bisazza, Angelo

    2016-07-01

    In many species, males and females have different reproductive roles and/or differ in their ecological niche. Since in these cases the two sexes often face different cognitive challenges, selection may promote some degree of cognitive differentiation, an issue that has received relatively little attention so far. We investigated the existence of sex differences in visual discrimination learning in the guppy, Poecilia reticulata, a fish species in which females show complex mate choice based on male colour pattern. We tested males and females for their ability to learn a discrimination between two different shapes (experiment 1) and between two identical figures with a different orientation (experiment 2). In experiment 3, guppies were required to select an object of the odd colour in a group of five objects. Colours changed daily, and therefore, the solution for this task was facilitated by concept learning. We found males' and females' accuracy practically overlapped in the three experiments, suggesting that the two sexes have similar discrimination learning abilities. Yet, males showed faster decision time than females without any evident speed-accuracy trade-off. This result indicates the existence of consistent between-sex differences in decision speed perhaps due to impulsivity rather than speed in information processing. Our results align with previous literature, indicating that sex differences in cognitive abilities are the exception rather than the rule, while sex differences in cognitive style, i.e. the way in which an individual faces a cognitive task, are much more common.

  4. Learning in mosquito larvae (Aedes aegypti): Habituation to a visual danger signal.

    Science.gov (United States)

    Baglan, Hugo; Lazzari, Claudio; Guerrieri, Fernando

    2017-01-07

    In spite of the mosquito Aedes aegypti being a vector of several infectious diseases, a limited number of studies has been undertaken on learning in this species. Moreover, larval stages have been neglected as model organisms, although they are active, aquatic and perform stereotyped behavioural responses, e.g. the escape response when disturbed. To study the learning abilities of mosquito larvae, we focused on habituation, a form of non-associative learning widely studied in vertebrates and invertebrates. Habituation was defined as the progressive and reversible decrease in response to a reiterative stimulus. We first aimed at confirming habituation of the escape response in mosquito larvae (4th instar). Then, we determined whether a mnesic trace was established. Larvae were individually stimulated with a visual danger stimulus inducing the escape response. We set up a protocol for testing larvae individually, allowing the control of different parameters that are crucial for the study of cognitive abilities. After 15 trials, the escape response of mosquitoes was significantly lower. A disturbance stimulus presented after the 15th trial, induced the escape response and reversed habituation. Retention was confirmed up to 1h after the last habituation trial. This original bioassay can be adapted for studying the physiology of learning and memory in mosquito larvae, for analysing the effects of chemicals in the water, the characterisation of the cognitive abilities related to the life history of different mosquito species across preimaginal stages.

  5. Learning an intrinsic-variable preserving manifold for dynamic visual tracking.

    Science.gov (United States)

    Qiao, Hong; Zhang, Peng; Zhang, Bo; Zheng, Suiwu

    2010-06-01

    Manifold learning is a hot topic in the field of computer science, particularly since nonlinear dimensionality reduction based on manifold learning was proposed in Science in 2000. The work has achieved great success. The main purpose of current manifold-learning approaches is to search for independent intrinsic variables underlying high dimensional inputs which lie on a low dimensional manifold. In this paper, a new manifold is built up in the training step of the process, on which the input training samples are set to be close to each other if the values of their intrinsic variables are close to each other. Then, the process of dimensionality reduction is transformed into a procedure of preserving the continuity of the intrinsic variables. By utilizing the new manifold, the dynamic tracking of a human who can move and rotate freely is achieved. From the theoretical point of view, it is the first approach to transfer the manifold-learning framework to dynamic tracking. From the application point of view, a new and low dimensional feature for visual tracking is obtained and successfully applied to the real-time tracking of a free-moving object from a dynamic vision system. Experimental results from a dynamic tracking system which is mounted on a dynamic robot validate the effectiveness of the new algorithm.

  6. Online dissection audio-visual resources for human anatomy: Undergraduate medical students' usage and learning outcomes.

    Science.gov (United States)

    Choi-Lundberg, Derek L; Cuellar, William A; Williams, Anne-Marie M

    2016-11-01

    In an attempt to improve undergraduate medical student preparation for and learning from dissection sessions, dissection audio-visual resources (DAVR) were developed. Data from e-learning management systems indicated DAVR were accessed by 28% ± 10 (mean ± SD for nine DAVR across three years) of students prior to the corresponding dissection sessions, representing at most 58% ± 20 of assigned dissectors. Approximately 50% of students accessed all available DAVR by the end of semester, while 10% accessed none. Ninety percent of survey respondents (response rate 58%) generally agreed that DAVR improved their preparation for and learning from dissection when used. Of several learning resources, only DAVR usage had a significant positive correlation (P = 0.002) with feeling prepared for dissection. Results on cadaveric anatomy practical examination questions in year 2 (Y2) and year 3 (Y3) cohorts were 3.9% (P Educ 9: 545-554. © 2016 American Association of Anatomists.

  7. Learning to Associate Auditory and Visual Stimuli: Behavioral and Neural Mechanisms

    Science.gov (United States)

    Altieri, Nicholas; Stevenson, Ryan; Wallace, Mark T.; Wenger, Michael J.

    2014-01-01

    The ability to effectively combine sensory inputs across modalities is vital for acquiring a unified percept of events. For example, watching a hammer hit a nail while simultaneously identifying the sound as originating from the event requires the ability to identify spatio-temporal congruencies and statistical regularities. In this study, we applied a reaction time (RT) and hazard function measure known as capacity (e.g., Townsend and Ashby, 1978) to quantify the extent to which observers learn paired associations between simple auditory and visual patterns in a model theoretic manner. As expected, results showed that learning was associated with an increase in accuracy, but more significantly, an increase in capacity. The aim of this study was to associate capacity measures of multisensory learning, with neural based measures, namely mean Global Field Power (GFP). We observed a co-variation between an increase in capacity, and a decrease in GFP amplitude as learning occurred. This suggests that capacity constitutes a reliable behavioral index of efficient energy expenditure in the neural domain. PMID:24276220

  8. Visual diet versus associative learning as mechanisms of change in body size preferences.

    Directory of Open Access Journals (Sweden)

    Lynda G Boothroyd

    Full Text Available Systematic differences between populations in their preferences for body size may arise as a result of an adaptive 'prepared learning' mechanism, whereby cues to health or status in the local population are internalized and affect body preferences. Alternatively, differences between populations may reflect their 'visual diet' as a cognitive byproduct of mere exposure. Here we test the relative importance of these two explanations for variation in body preferences. Two studies were conducted where female observers were exposed to pictures of high or low BMI women which were either aspirational (healthy, attractive models in high status clothes or non-aspirational (eating disordered patients in grey leotards, or to combinations thereof, in order to manipulate their body-weight preferences which were tested at baseline and at post-test. Overall, results showed good support for visual diet effects (seeing a string of small or large bodies resulted in a change from pre- to post-test whether the bodies were aspirational or not and also some support for the associative learning explanation (exposure to aspirational images of overweight women induced a towards preferring larger bodies, even when accompanied by equal exposure to lower weight bodies in the non-aspirational category. Thus, both influences may act in parallel.

  9. Applications of machine learning and high-dimensional visualization in cancer detection, diagnosis, and management.

    Science.gov (United States)

    McCarthy, John F; Marx, Kenneth A; Hoffman, Patrick E; Gee, Alexander G; O'Neil, Philip; Ujwal, M L; Hotchkiss, John

    2004-05-01

    Recent technical advances in combinatorial chemistry, genomics, and proteomics have made available large databases of biological and chemical information that have the potential to dramatically improve our understanding of cancer biology at the molecular level. Such an understanding of cancer biology could have a substantial impact on how we detect, diagnose, and manage cancer cases in the clinical setting. One of the biggest challenges facing clinical oncologists is how to extract clinically useful knowledge from the overwhelming amount of raw molecular data that are currently available. In this paper, we discuss how the exploratory data analysis techniques of machine learning and high-dimensional visualization can be applied to extract clinically useful knowledge from a heterogeneous assortment of molecular data. After an introductory overview of machine learning and visualization techniques, we describe two proprietary algorithms (PURS and RadViz) that we have found to be useful in the exploratory analysis of large biological data sets. We next illustrate, by way of three examples, the applicability of these techniques to cancer detection, diagnosis, and management using three very different types of molecular data. We first discuss the use of our exploratory analysis techniques on proteomic mass spectroscopy data for the detection of ovarian cancer. Next, we discuss the diagnostic use of these techniques on gene expression data to differentiate between squamous and adenocarcinoma of the lung. Finally, we illustrate the use of such techniques in selecting from a database of chemical compounds those most effective in managing patients with melanoma versus leukemia.

  10. Dopamine in motivational control: rewarding, aversive, and alerting.

    Science.gov (United States)

    Bromberg-Martin, Ethan S; Matsumoto, Masayuki; Hikosaka, Okihide

    2010-12-09

    Midbrain dopamine neurons are well known for their strong responses to rewards and their critical role in positive motivation. It has become increasingly clear, however, that dopamine neurons also transmit signals related to salient but nonrewarding experiences such as aversive and alerting events. Here we review recent advances in understanding the reward and nonreward functions of dopamine. Based on this data, we propose that dopamine neurons come in multiple types that are connected with distinct brain networks and have distinct roles in motivational control. Some dopamine neurons encode motivational value, supporting brain networks for seeking, evaluation, and value learning. Others encode motivational salience, supporting brain networks for orienting, cognition, and general motivation. Both types of dopamine neurons are augmented by an alerting signal involved in rapid detection of potentially important sensory cues. We hypothesize that these dopaminergic pathways for value, salience, and alerting cooperate to support adaptive behavior.

  11. Running-based pica in rats. Evidence for the gastrointestinal discomfort hypothesis of running-based taste aversion.

    Science.gov (United States)

    Nakajima, Sadahiko; Katayama, Tomomi

    2014-12-01

    Voluntary running in an activity wheel establishes aversion to paired taste in rats. A proposed mechanism underlying this taste aversion learning is gastrointestinal discomfort caused by running. We tested this hypothesis by measuring the pica behavior (kaolin clay intake) of rats, because it is known that rats engage in pica behavior after various nausea-inducing treatments including irradiation, motion sickness, and injection of emetic drugs such as lithium chloride (LiCl). Following a demonstration of the already-known phenomenon of LiCl-based pica in Experiment 1, we successfully showed running-based pica behavior in Experiment 2 where the running treatment was compared with a non-running control treatment (i.e., confinement in a locked wheel). These results suggest that not only LiCl but also running induces nausea in rats, supporting the gastrointestinal discomfort hypothesis of running-based taste aversion learning.

  12. READING AUTHENTIC EFL TEXT USING VISUALIZATION AND ADVANCE ORGANIZERS IN A MULTIMEDIA LEARNING ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Tsuiping Chen

    2007-02-01

    Full Text Available The purpose of this experimental study was to compare the effects of different types of computer-generated visuals (static versus animated and advance organizers (descriptive versus question in enhancing comprehension and retention of a content-based lesson for learning English as a Foreign Language (EFL. Additionally, the study investigated the interactive effect of students’ existing reading proficiency level and the above-mentioned treatments on their reading comprehension achievement. Students from two EFL reading sections (N = 115 were tested on their reading proficiency and then randomly assigned to one of four computer-based instructional modules—static visual alone, animation alone, animation plus descriptive advance organizer, and animation plus question advance organizer. Once having interacted with their respective instructional materials, students then took four criterion tests immediately afterward and again four weeks later. The results showed that the animation group outperformed the static visual group in one of the four tests, and that animation embedded with a question advance organizer had a marginal effect among the four treatments in facilitating the acquisition of L2 reading comprehension both for the immediate and the delayed posttests.

  13. Scalable Linear Visual Feature Learning via Online Parallel Nonnegative Matrix Factorization.

    Science.gov (United States)

    Zhao, Xueyi; Li, Xi; Zhang, Zhongfei; Shen, Chunhua; Zhuang, Yueting; Gao, Lixin; Li, Xuelong

    2016-12-01

    Visual feature learning, which aims to construct an effective feature representation for visual data, has a wide range of applications in computer vision. It is often posed as a problem of nonnegative matrix factorization (NMF), which constructs a linear representation for the data. Although NMF is typically parallelized for efficiency, traditional parallelization methods suffer from either an expensive computation or a high runtime memory usage. To alleviate this problem, we propose a parallel NMF method called alternating least square block decomposition (ALSD), which efficiently solves a set of conditionally independent optimization subproblems based on a highly parallelized fine-grained grid-based blockwise matrix decomposition. By assigning each block optimization subproblem to an individual computing node, ALSD can be effectively implemented in a MapReduce-based Hadoop framework. In order to cope with dynamically varying visual data, we further present an incremental version of ALSD, which is able to incrementally update the NMF solution with a low computational cost. Experimental results demonstrate the efficiency and scalability of the proposed methods as well as their applications to image clustering and image retrieval.

  14. Inequity aversion and the evolution of cooperation

    Science.gov (United States)

    Ahmed, Asrar; Karlapalem, Kamalakar

    2014-02-01

    Evolution of cooperation is a widely studied problem in biology, social science, economics, and artificial intelligence. Most of the existing approaches that explain cooperation rely on some notion of direct or indirect reciprocity. These reciprocity based models assume agents recognize their partner and know their previous interactions, which requires advanced cognitive abilities. In this paper we are interested in developing a model that produces cooperation without requiring any explicit memory of previous game plays. Our model is based on the notion of inequity aversion, a concept introduced within behavioral economics, whereby individuals care about payoff equality in outcomes. Here we explore the effect of using income inequality to guide partner selection and interaction. We study our model by considering both the well-mixed and the spatially structured population and present the conditions under which cooperation becomes dominant. Our results support the hypothesis that inequity aversion promotes cooperative relationship among nonkin.

  15. Differential participation of temporal structures in the consolidation and reconsolidation of taste aversion extinction.

    Science.gov (United States)

    Garcia-Delatorre, Paola; Rodríguez-Ortiz, Carlos J; Balderas, Israela; Bermúdez-Rattoni, Federico

    2010-09-01

    The extinction process has been described as the decline in the frequency or intensity of the conditioned response following the withdrawal of reinforcement. Hence, experimental extinction does not reflect loss of the original memory, but rather reflects new learning, which in turn requires consolidation in order to be maintained in the long term. During extinction of conditioned taste aversion (CTA), a taste previously associated with aversive consequences acquires a safe status through continuous presentations of the flavor with no aversive consequence. In addition, reconsolidation has been defined as the labile state of a consolidated memory after its reactivation by the presentation of relevant information. In this study, we analyzed structures from the temporal lobe that could be involved in consolidation and reconsolidation of extinction of CTA by means of new protein synthesis. Our results showed that protein synthesis in the hippocampus (HC), the perirhinal cortex (PR) and the insular cortex (IC) of rats participate in extinction consolidation, whereas the basolateral amygdala plays no part in this phenomenon. Furthermore, we found that inhibition of protein synthesis in the IC in a third extinction trial had an effect on reconsolidation of extinction. The participation of the HC in taste memory has been described as a downmodulator for CTA consolidation, and has been related to a context-taste association. Altogether, these data suggest that extinction of aversive taste memories are subserved by the IC, HC and PR, and that extinction can undergo reconsolidation, a process depending only on the IC.

  16. Spatial discrimination and visual discrimination: two methods evaluating learning and memory in juvenile Göttingen minipigs.

    Science.gov (United States)

    Haagensen, Annika M J; Grand, Nanna; Klastrup, Signe; Skytte, Christina; Sørensen, Dorte B

    2013-06-01

    Two methods investigating learning and memory in juvenile Göttingen minipigs were evaluated for potential use in preclinical toxicity testing. Twelve minipigs were tested using a spatial hole-board discrimination test including a learning phase and two memory phases. Five minipigs were tested in a visual discrimination test. The juvenile minipigs were able to learn the spatial hole-board discrimination test and showed improved working and reference memory during the learning phase. Performance in the memory phases was affected by the retention intervals, but the minipigs were able to remember the concept of the test in both memory phases. Working memory and reference memory were significantly improved in the last trials of the memory phases. In the visual discrimination test, the minipigs learned to discriminate between the three figures presented to them within 9-14 sessions. For the memory test, all minipigs performed 9/12 correct choices or better. Juvenile Göttingen minipigs are able to learn to perform in a spatial hole-board discrimination test as well as in a visual discrimination test, showing an increase in performance over time. Both tests have considerable scope to assess learning and memory of pigs, and we seem to have succeeded in establishing two test systems suitable for performing preclinical toxicity testing in juvenile minipigs.

  17. Visual literacy and visual communication for global education: innovations in teaching e-learning in art, design and communication

    NARCIS (Netherlands)

    Velders, Teun; Vries, de Sjoerd; Vaicaityte, Loreta

    2007-01-01

    This paper presents the (student) proceedings of a successful inter-university co-operation between a research university and a university of applied sciences, in the field of Visual Literacy and Visual Communication. The origin lays in the international symposium “Digital Communities for Global Edu

  18. Neural compensation in adulthood following very preterm birth demonstrated during a visual paired associates learning task

    Directory of Open Access Journals (Sweden)

    Philip J. Brittain

    2014-01-01

    Full Text Available Very preterm birth (VPT; < 33 weeks of gestation is associated with an increased risk of learning disability, which contributes to more VPT-born children repeating grades and underachieving in school. Learning problems associated with VPT birth may be caused by pathophysiological alterations in neurodevelopment resulting from perinatal brain insult; however, adaptive neuroplastic processes may subsequently occur in the developing preterm brain which ameliorate, to an extent, the potential sequelae of altered neurophysiology. Here, we used functional magnetic resonance imaging (fMRI to compare neuronal activation in 24 VPT individuals and 22 controls (CT in young adulthood during a learning task consisting of the encoding and subsequent recognition of repeated visual paired associates. Structural MRI data were also collected and analysed in order to explore possible structure-function associations. Whilst the two groups did not differ in their learning ability, as demonstrated by their capacity to recognize previously-seen and previously–unseen visual pairs, between-group differences in linear patterns of Blood Oxygenation Level Dependant (BOLD activity were observed across the four repeated blocks of the task for both the encoding and recognition conditions, suggesting that the way learning takes place differs between the two groups. During encoding, significant between-group differences in patterns of BOLD activity were seen in clusters centred on the cerebellum, the anterior cingulate gyrus, the midbrain/substantia nigra, medial temporal (including parahippocampal gyrus and inferior and superior frontal gyri. During the recognition condition, significant between-group differences in patterns of BOLD activity were seen in clusters centred on the claustrum and the posterior cerebellum. Structural analysis revealed smaller grey matter volume in right middle temporal gyrus in VPT individuals compared to controls, however volume in this region

  19. Stereoscopy in Astronomical Visualizations to Support Learning at Informal Education Settings

    Science.gov (United States)

    Price, Aaron; Lee, Hee-Sun

    2015-08-01

    Stereoscopy has been used in science education for 100 years. Recent innovations in low cost technology as well as trends in the entertainment industry have made stereoscopy popular among educators and audiences alike. However, experimental studies addressing whether stereoscopy actually impacts science learning are limited. Over the last decade, we have conducted a series of quasi-experimental and experimental studies on how children and adult visitors in science museums and planetariums learned about the structure and function of highly spatial scientific objects such as galaxies, supernova, etc. We present a synthesis of the results from these studies and implications for stereoscopic visualization development. The overall finding is that the impact of stereoscopy on perceptions of scientific objects is limited when presented as static imagery. However, when presented as full motion films, a significantly positive impact was detected. To conclude, we present a set of stereoscopic design principles that can help design astronomical stereoscopic films that support deep and effective learning. Our studies cover astronomical content such as the engineering of and imagery from the Mars rovers, artistic stereoscopic imagery of nebulae and a high-resolution stereoscopic film about how astronomers measure and model the structure of our galaxy.

  20. Real time unsupervised learning of visual stimuli in neuromorphic VLSI systems

    Science.gov (United States)

    Giulioni, Massimiliano; Corradi, Federico; Dante, Vittorio; Del Giudice, Paolo

    2015-10-01

    Neuromorphic chips embody computational principles operating in the nervous system, into microelectronic devices. In this domain it is important to identify computational primitives that theory and experiments suggest as generic and reusable cognitive elements. One such element is provided by attractor dynamics in recurrent networks. Point attractors are equilibrium states of the dynamics (up to fluctuations), determined by the synaptic structure of the network; a ‘basin’ of attraction comprises all initial states leading to a given attractor upon relaxation, hence making attractor dynamics suitable to implement robust associative memory. The initial network state is dictated by the stimulus, and relaxation to the attractor state implements the retrieval of the corresponding memorized prototypical pattern. In a previous work we demonstrated that a neuromorphic recurrent network of spiking neurons and suitably chosen, fixed synapses supports attractor dynamics. Here we focus on learning: activating on-chip synaptic plasticity and using a theory-driven strategy for choosing network parameters, we show that autonomous learning, following repeated presentation of simple visual stimuli, shapes a synaptic connectivity supporting stimulus-selective attractors. Associative memory develops on chip as the result of the coupled stimulus-driven neural activity and ensuing synaptic dynamics, with no artificial separation between learning and retrieval phases.

  1. User-Centered Design of E-Learning Tools for Users with Special Needs: The VisualPedia Case Study

    Directory of Open Access Journals (Sweden)

    Stefano Valtolina

    2012-10-01

    Full Text Available The design of multimedia systems in the e-learning context poses several challenges in term of developing usable and accessible applications. This paper presents a case study related to VisualPedia, a collaborative multimedia e-learning system, whose software lifecycle has followed a participatory design and the analysis of specific phenomena characterizing the HCI process. The goal of this work is to highlight that the adoption of these approaches from the early design phase will lead to make useful, usable and accessible multimedia interactive systems. Results are validated by showing some usability and accessibility analysis carried out in the context of the VisualPedia development process.

  2. Aversive picture processing: effects of a concurrent task on sustained defensive system engagement.

    Science.gov (United States)

    Wangelin, Bethany C; Löw, Andreas; McTeague, Lisa M; Bradley, Margaret M; Lang, Peter J

    2011-01-01

    Viewing a series of aversive pictures prompts emotional reactivity reflecting sustained defensive engagement. The present study examined the effects of a concurrent visual task on autonomic, somatic, electrocortical, and facial components of this defensive state. Results indicated that emotional activation was largely preserved despite continuous visual distraction, although evidence of attenuation was observed in startle reflex and electrocortical measures. Concurrent task-specific reactivity was also apparent, suggesting that motivational circuits can be simultaneously activated by stimuli with intrinsic survival significance and instructed task significance and that these processes interact differently across the separate components of defensive engagement.

  3. EFFECT OF THE AMOUNT OF ALLOWED VISUAL INFORMATION ON ACROBATIC SKILL LEARNING

    Directory of Open Access Journals (Sweden)

    L. Morenilla

    2010-09-01

    Full Text Available

     

    ABSTRACT

    Postural control is the result of different sensorial information integration. During complex movements, such as acrobatic skills when a subject jumps and turns on the transversal axis, sensorial conflicts can appear, especially among visual and vestibular inputs. The importance of these conflicts during learning and posterior execution of an acrobatic manoeuvre is not clear. An experimental study was carried out where we controlled the environmental illumination of flying and landing phases of an acrobatic skill execution (forward tucked somersault during the learning process. We obtained significant differences between different practice groups, showing better results those subjects who accomplished their practice without illumination during the landing phase. Our results suggest that although visual information might be important to perform the take-off phase correctly, it doesn’t seem to be a determining factor on its final phase (landing and could even interfere with vestibular information.
    KEYWORDS: sensorymotor integration, vision, vestibular information, acrobatic activities

     

    RESUMEN

    El control postural es el resultado de la integración de diferentes informaciones sensoriales. En la ejecución de movimientos complejos, como las habilidades acrobáticas basadas en saltar y girar en torno al eje transversal, pueden aparecer conflictos sensoriales, especialmente entre la información visual y la vestibular. La repercusión de estos conflictos sobre el aprendizaje y dominio de este tipo de habilidad no esta clara. Se realizó un estudio experimental, en el cual la iluminación del ambiente fue

  4. Effects of direct instruction of visual literacy skills on science achievement when integrated into inquiry learning

    Science.gov (United States)

    Galyas, Lesley Crowell

    Understanding of visual representations is a pivotal skill necessary in science. These visual, verbal, and numeric representations are the crux of science discourses "by scientists, with students and the general public" (Pauwels, 2006, p.viii). Those who lack the understanding of these representations see it as a foreign language, one that they have never been taught to interpret. Roth, Bowen and Masciotra (2002) assert that students lack the necessary preparation to interpret scientific representational practices thoughtfully and skillfully and are not equipped to decipher the combinations of "divergent representational systems (graphs, images, equations) in a meaningful and edifying whole" (Pauwels, 2006, p.x). Several studies confirm that when students are unable to retrieve and apply knowledge, they will have difficulties with problem solving, critical thinking, and learning new material; moreover this has been demonstrated among all ability levels (O'Reilly & McNamara, 2007). The purpose of this mixed method case study was to explore the use of deliberate instruction of visual literacy skills embedded within inquiry science learning, utilizing the TLC method, for middle school students in a single classroom. Pre- and post-testing, teacher interviews and classroom observations were utilized. The study had three phases pre-implementation, implementation of TLC, and post implementation. The analysis was based on the Embedded Experimental Model. "This model is defined by having qualitative data embedded within an experimental design" (Creswell, 2007, Loc 806 of 3545). The 7th grade science classes studied are dual language immersion with 93% Hispanic and 100% economically disadvantaged students. These classes were taught by a single teacher where native Spanish speakers were taught in Spanish and English speakers were taught in English. The data for final test scores for students taught in English (English speakers, and EL exited) resulted in t (21)=5.42, * p

  5. Shared mushroom body circuits underlie visual and olfactory memories in Drosophila.

    Science.gov (United States)

    Vogt, Katrin; Schnaitmann, Christopher; Dylla, Kristina V; Knapek, Stephan; Aso, Yoshinori; Rubin, Gerald M; Tanimoto, Hiromu

    2014-08-19

    In nature, animals form memories associating reward or punishment with stimuli from different sensory modalities, such as smells and colors. It is unclear, however, how distinct sensory memories are processed in the brain. We established appetitive and aversive visual learning assays for Drosophila that are comparable to the widely used olfactory learning assays. These assays share critical features, such as reinforcing stimuli (sugar reward and electric shock punishment), and allow direct comparison of the cellular requirements for visual and olfactory memories. We found that the same subsets of dopamine neurons drive formation of both sensory memories. Furthermore, distinct yet partially overlapping subsets of mushroom body intrinsic neurons are required for visual and olfactory memories. Thus, our results suggest that distinct sensory memories are processed in a common brain center. Such centralization of related brain functions is an economical design that avoids the repetition of similar circuit motifs.

  6. A Moist Crevice for Word Aversion: In Semantics Not Sounds.

    Directory of Open Access Journals (Sweden)

    Paul H Thibodeau

    Full Text Available Why do people self-report an aversion to words like "moist"? The present studies represent an initial scientific exploration into the phenomenon of word aversion by investigating its prevalence and cause. Results of five experiments indicate that about 10-20% of the population is averse to the word "moist." This population often speculates that phonological properties of the word are the cause of their displeasure. However, data from the current studies point to semantic features of the word-namely, associations with disgusting bodily functions-as a more prominent source of peoples' unpleasant experience. "Moist," for averse participants, was notable for its valence and personal use, rather than imagery or arousal-a finding that was confirmed by an experiment designed to induce an aversion to the word. Analyses of individual difference measures suggest that word aversion is more prevalent among younger, more educated, and more neurotic people, and is more commonly reported by females than males.

  7. Region-Specific Involvement of Actin Rearrangement-Related Synaptic Structure Alterations in Conditioned Taste Aversion Memory

    Science.gov (United States)

    Bi, Ai-Ling; Wang, Yue; Li, Bo-Qin; Wang, Qian-Qian; Ma, Ling; Yu, Hui; Zhao, Ling; Chen, Zhe-Yu

    2010-01-01

    Actin rearrangement plays an essential role in learning and memory; however, the spatial and temporal regulation of actin dynamics in different phases of associative memory has not been fully understood. Here, using the conditioned taste aversion (CTA) paradigm, we investigated the region-specific involvement of actin rearrangement-related…

  8. The Role of Muscarinic and Nicotinic Cholinergic Neurotransmission in Aversive Conditioning: Comparing Pavlovian Fear Conditioning and Inhibitory Avoidance

    Science.gov (United States)

    Tinsley, Matthew R.; Quinn, Jennifer J.; Fanselow, Michael S.

    2004-01-01

    Aversive conditioning is an ideal model for studying cholinergic effects on the processes of learning and memory for several reasons. First, deficits produced by selective lesions of the anatomical structures shown to be critical for Pavlovian fear conditioning and inhibitory avoidance (such as the amygdala and hippocampus) resemble those deficits…

  9. A Comparison of Two Methods of Assessing Representation-Mediated Food Aversions Based on Shock or Illness

    Science.gov (United States)

    Holland, Peter C.

    2008-01-01

    In experiments that measured food consumption, Holland (1981; "Learning and Motivation," 12, 1-18) found that food aversions were formed when an exteroceptive associate of food was paired with illness, but not when such an associate was paired with shock. By contrast, measuring the ability of food to reinforce instrumental responding,…

  10. Hippocampal Erk Mechanisms Linking Prediction Error to Fear Extinction: Roles of Shock Expectancy and Contextual Aversive Valence

    Science.gov (United States)

    Huh, Kyu Hwan; Guzman, Yomayra F.; Tronson, Natalie C.; Guedea, Anita L.; Gao, Can; Radulovic, Jelena

    2009-01-01

    Extinction of fear requires learning that anticipated aversive events no longer occur. Animal models reveal that sustained phosphorylation of the extracellular signal-regulated kinase (Erk) in hippocampal CA1 neurons plays an important role in this process. However, the key signals triggering and regulating the activity of Erk are not known. By…

  11. Medial amygdala lesions selectively block aversive Pavlovian-instrumental transfer in rats.

    Directory of Open Access Journals (Sweden)

    Margaret Grace McCue

    2014-09-01

    Full Text Available Pavlovian conditioned stimuli (CSs play an important role in the reinforcement and motivation of instrumental active avoidance (AA. Conditioned threats can also invigorate ongoing AA responding (aversive Pavlovian-instrumental transfer or PIT. The neural circuits mediating AA are poorly understood, although lesion studies suggest that lateral, basal and central amygdala nuclei, as well as infralimbic prefrontal cortex, make key, and sometimes opposing, contributions. We recently completed an extensive analysis of brain c-Fos expression in good vs. poor avoiders following an AA test (Martinez et al 2013, Learning and Memory. This analysis identified medial amygdala (MeA as a potentially important region for Pavlovian motivation of instrumental actions. MeA is known to mediate defensive responding to innate threats as well as social behaviors, but its role in mediating aversive Pavlovian-instrumental interactions is unknown. We evaluated the effect of MeA lesions on Pavlovian conditioning, Sidman two-way AA conditioning (shuttling and aversive PIT in rats. Mild footshocks served as the unconditioned stimulus in all conditioning phases. MeA lesions had no effect on AA but blocked the expression of aversive PIT and 22 kHz ultrasonic vocalizations in the AA context. Interestingly, MeA lesions failed to affect Pavlovian freezing to discrete threats but reduced freezing to contextual threats when assessed outside of the AA chamber. These findings differentiate MeA from lateral and central amygdala, as lesions of these nuclei disrupt Pavlovian freezing and aversive PIT, but have opposite effects on AA performance. Taken together, these results suggest that MeA plays a selective role in the motivation of instrumental avoidance by general or uncertain Pavlovian threats.

  12. Comparison on testability of visual acuity, stereo acuity and colour vision tests between children with learning disabilities and children without learning disabilities in government primary schools

    Directory of Open Access Journals (Sweden)

    Nurul Farhana Abu Bakar

    2014-01-01

    Full Text Available Context: Children with learning disabilities might have difficulties to communicate effectively and give reliable responses as required in various visual function testing procedures. Aims: The purpose of this study was to compare the testability of visual acuity using the modified Early Treatment Diabetic Retinopathy Study (ETDRS and Cambridge Crowding Cards, stereo acuity using Lang Stereo test II and Butterfly stereo tests and colour perception using Colour Vision Test Made Easy (CVTME and Ishihara′s Test for Colour Deficiency (Ishihara Test between children in mainstream classes and children with learning disabilities in special education classes in government primary schools. Materials and Methods: A total of 100 primary school children (50 children from mainstream classes and 50 children from special education classes matched in age were recruited in this cross-sectional comparative study. The testability was determined by the percentage of children who were able to give reliable respond as required by the respective tests. ′Unable to test′ was defined as inappropriate response or uncooperative despite best efforts of the screener. Results: The testability of the modified ETDRS, Butterfly stereo test and Ishihara test for respective visual function tests were found lower among children in special education classes ( P < 0.001 but not in Cambridge Crowding Cards, Lang Stereo test II and CVTME. Conclusion: Non verbal or "matching" approaches were found to be more superior in testing visual functions in children with learning disabilities. Modifications of vision testing procedures are essential for children with learning disabilities.

  13. Lateral occipitotemporal cortex (LOTC) activity is greatest while viewing dance compared to visualization and movement: learning and expertise effects.

    Science.gov (United States)

    Di Nota, Paula M; Levkov, Gabriella; Bar, Rachel; DeSouza, Joseph F X

    2016-07-01

    The lateral occipitotemporal cortex (LOTC) is comprised of subregions selectively activated by images of human bodies (extrastriate body area, EBA), objects (lateral occipital complex, LO), and motion (MT+). However, their role in motor imagery and movement processing is unclear, as are the influences of learning and expertise on its recruitment. The purpose of our study was to examine putative changes in LOTC activation during action processing following motor learning of novel choreography in professional ballet dancers. Subjects were scanned with functional magnetic resonance imaging up to four times over 34 weeks and performed four tasks: viewing and visualizing a newly learned ballet dance, visualizing a dance that was not being learned, and movement of the foot. EBA, LO, and MT+ were activated most while viewing dance compared to visualization and movement. Significant increases in activation were observed over time in left LO only during visualization of the unlearned dance, and all subregions were activated bilaterally during the viewing task after 34 weeks of performance, suggesting learning-induced plasticity. Finally, we provide novel evidence for modulation of EBA with dance experience during the motor task, with significant activation elicited in a comparison group of novice dancers only. These results provide a composite of LOTC activation during action processing of newly learned ballet choreography and movement of the foot. The role of these areas is confirmed as primarily subserving observation of complex sequences of whole-body movement, with new evidence for modification by experience and over the course of real world ballet learning.

  14. Self-Organization of Spatio-Temporal Hierarchy via Learning of Dynamic Visual Image Patterns on Action Sequences.

    Science.gov (United States)

    Jung, Minju; Hwang, Jungsik; Tani, Jun

    2015-01-01

    It is well known that the visual cortex efficiently processes high-dimensional spatial information by using a hierarchical structure. Recently, computational models that were inspired by the spatial hierarchy of the visual cortex have shown remarkable performance in image recognition. Up to now, however, most biological and computational modeling studies have mainly focused on the spatial domain and do not discuss temporal domain processing of the visual cortex. Several studies on the visual cortex and other brain areas associated with motor control support that the brain also uses its hierarchical structure as a processing mechanism for temporal information. Based on the success of previous computational models using spatial hierarchy and temporal hierarchy observed in the brain, the current report introduces a novel neural network model for the recognition of dynamic visual image patterns based solely on the learning of exemplars. This model is characterized by the application of both spatial and temporal constraints on local neural activities, resulting in the self-organization of a spatio-temporal hierarchy necessary for the recognition of complex dynamic visual image patterns. The evaluation with the Weizmann dataset in recognition of a set of prototypical human movement patterns showed that the proposed model is significantly robust in recognizing dynamically occluded visual patterns compared to other baseline models. Furthermore, an evaluation test for the recognition of concatenated sequences of those prototypical movement patterns indicated that the model is endowed with a remarkable capability for the contextual recognition of long-range dynamic visual image patterns.

  15. Measures for Inclusion: Coping with the Challenge of Visual Impairment and Blindness in University Undergraduate Level Language Learning

    Science.gov (United States)

    Orsini-Jones, Marina

    2009-01-01

    This paper develops from previous research (Orsini-Jones et al., 2005) and reports on the experience of three students, two visually impaired and one blind, reading languages at Coventry University, on the adjustments made to meet their needs and on the challenges encountered on their learning journey both from their point of view and from the…

  16. Provision of Learning and Teaching Materials for Pupils with Visual Impairment: Results from a National Survey in Zambia

    Science.gov (United States)

    Akakandelwa, Akakandelwa; Munsanje, Joseph

    2012-01-01

    The aim of this study was to determine the provision of learning and teaching materials for pupils with visual impairment in basic and high schools of Zambia. A survey approach utilizing a questionnaire, interviews and a review of the literature was adopted for the study. The findings demonstrated that most schools in Zambia did not provide…

  17. 3D Visualization Types in Multimedia Applications for Science Learning: A Case Study for 8th Grade Students in Greece

    Science.gov (United States)

    Korakakis, G.; Pavlatou, E. A.; Palyvos, J. A.; Spyrellis, N.

    2009-01-01

    This research aims to determine whether the use of specific types of visualization (3D illustration, 3D animation, and interactive 3D animation) combined with narration and text, contributes to the learning process of 13- and 14- years-old students in science courses. The study was carried out with 212 8th grade students in Greece. This…

  18. Using Virtual Microscopy to Scaffold Learning of Pathology: A Naturalistic Experiment on the Role of Visual and Conceptual Cues

    Science.gov (United States)

    Nivala, Markus; Saljo, Roger; Rystedt, Hans; Kronqvist, Pauliina; Lehtinen, Erno

    2012-01-01

    New representational technologies, such as virtual microscopy, create new affordances for medical education. In the article, a study on the following two issues is reported: (a) How does collaborative use of virtual microscopy shape students' engagement with and learning from virtual slides of tissue specimen? (b) How do visual and conceptual cues…

  19. Widening Possibilities of Interpretation When Observing Learning and Teaching through the Use of a Dynamic Visual Notation

    Science.gov (United States)

    Kell, Clare; Sweet, John

    2017-01-01

    This paper shows how peer observation of learning and teaching (POLT) discussions can be augmented through the use of a dynamic visual notation that makes visible for interpretation, elements of teacher-learner and learner-earner nonverbal interactions. Making visible the nonverbal, physical, spatial and kinesics (eye-based) elements of…

  20. Assessing the Effects of Different Multimedia Materials on Emotions and Learning Performance for Visual and Verbal Style Learners

    Science.gov (United States)

    Chen, Chih-Ming; Sun, Ying-Chun

    2012-01-01

    Multimedia materials are now increasingly used in curricula. However, individual preferences for multimedia materials based on visual and verbal cognitive styles may affect learners' emotions and performance. Therefore, in-depth studies that investigate how different multimedia materials affect learning performance and the emotions of learners…

  1. Interlocking Toy Building Blocks as Hands-On Learning Modules for Blind and Visually Impaired Chemistry Students

    Science.gov (United States)

    Melaku, Samuel; Schreck, James O.; Griffin, Kameron; Dabke, Rajeev B.

    2016-01-01

    Interlocking toy building blocks (e.g., Lego) as chemistry learning modules for blind and visually impaired (BVI) students in high school and undergraduate introductory or general chemistry courses are presented. Building blocks were assembled on a baseplate to depict the relative changes in the periodic properties of elements. Modules depicting…

  2. Investigating an Application of Speech-to-Text Recognition: A Study on Visual Attention and Learning Behaviour

    Science.gov (United States)

    Huang, Y-M.; Liu, C-J.; Shadiev, Rustam; Shen, M-H.; Hwang, W-Y.

    2015-01-01

    One major drawback of previous research on speech-to-text recognition (STR) is that most findings showing the effectiveness of STR for learning were based upon subjective evidence. Very few studies have used eye-tracking techniques to investigate visual attention of students on STR-generated text. Furthermore, not much attention was paid to…

  3. Comparison of Scores on Two Visual-Motor Tests for Children Referred for Learning or Adjustment Difficulties.

    Science.gov (United States)

    DeMers, Stephen T.; And Others

    1981-01-01

    This study compared the performance of school-aged children referred for learning or adjustment difficulties on Beery's Developmental Test of Visual-Motor Integration and Koppitz's version of the Bender-Gestalt test. Results indicated that the tests are related but not equivalent when administered to referred populations. (Author/AL)

  4. EXEL; Experience for Children in Learning. Parent-Directed Activities to Develop: Oral Expression, Visual Discrimination, Auditory Discrimination, Motor Coordination.

    Science.gov (United States)

    Behrmann, Polly; Millman, Joan

    The activities collected in this handbook are planned for parents to use with their children in a learning experience. They can also be used in the classroom. Sections contain games designed to develop visual discrimination, auditory discrimination, motor coordination and oral expression. An objective is given for each game, and directions for…

  5. TrAVis to Enhance Online Tutoring and Learning Activities: Real-Time Visualization of Students Tracking Data

    Science.gov (United States)

    May, Madeth; George, Sebastien; Prevot, Patrick

    2011-01-01

    Purpose: This paper presents a part of our research work that places an emphasis on Tracking Data Analysis and Visualization (TrAVis) tools, a web-based system, designed to enhance online tutoring and learning activities, supported by computer-mediated communication (CMC) tools. TrAVis is particularly dedicated to assist both tutors and students…

  6. An insect-inspired model for visual binding I: learning objects and their characteristics.

    Science.gov (United States)

    Northcutt, Brandon D; Dyhr, Jonathan P; Higgins, Charles M

    2017-04-01

    Visual binding is the process of associating the responses of visual interneurons in different visual submodalities all of which are responding to the same object in the visual field. Recently identified neuropils in the insect brain termed optic glomeruli reside just downstream of the optic lobes and have an internal organization that could support visual binding. Working from anatomical similarities between optic and olfactory glomeruli, we have developed a model of visual binding based on common temporal fluctuations among signals of independent visual submodalities. Here we describe and demonstrate a neural network model capable both of refining selectivity of visual information in a given visual submodality, and of associating visual signals produced by different objects in the visual field by developing inhibitory neural synaptic weights representing the visual scene. We also show that this model is consistent with initial physiological data from optic glomeruli. Further, we discuss how this neural network model may be implemented in optic glomeruli at a neuronal level.

  7. Spatial Visualization Tasks To Support Students’ Spatial Structuring In Learning Volume Measurement

    Directory of Open Access Journals (Sweden)

    Shintia Revina

    2011-07-01

    Full Text Available Many prior researches found that most of students in grade five tendedto have difficulty in fully grasping the concept of volume measurementbecause they have to build their competence in spatial structuring. The unit of volume “packing” measurement must be integrated andcoordinated in three-dimension. On the other hand, it is revealed theerrors that students made on the volume measurement tasks with threedimensional cube arrays are related to some aspects of spatialvisualization, such as the skill to "read off" two-dimensionalrepresentation of solid objects. For those reasons, this research is aimed to develop classroom activities with the use of spatial visualization tasks to support students’ spatial structuring in learning volume measurement. Consequently, design research was chosen as an appropriate means to achieve this research goal. In this research, a sequence of instructional activities is designed and developed based on the hypothesis of students’ learning processes. This research was conducted in grade 5 of SD Pupuk Sriwijaya Palembang, Indonesia

  8. A visual tracking method based on improved online multiple instance learning

    Science.gov (United States)

    He, Xianhui; Wei, Yuxing

    2016-09-01

    Visual tracking is an active research topic in the field of computer vision and has been well studied in the last decades. The method based on multiple instance learning (MIL) was recently introduced into the tracking task, which can solve the problem that template drift well. However, MIL method has relatively poor performance in running efficiency and accuracy, due to its strong classifiers updating strategy is complicated, and the speed of the classifiers update is not always same with the change of the targets' appearance. In this paper, we present a novel online effective MIL (EMIL) tracker. A new update strategy for strong classifier was proposed to improve the running efficiency of MIL method. In addition, to improve the t racking accuracy and stability of the MIL method, a new dynamic mechanism for learning rate renewal of the classifier and variable search window were proposed. Experimental results show that our method performs good performance under the complex scenes, with strong stability and high efficiency.

  9. Conceptualizing science learning as a collective social practice: changing the social pedagogical compass for a child with visual impairment

    Science.gov (United States)

    Fleer, Marilyn; March, Sue

    2015-09-01

    The international literature on science learning in inclusive settings has a long history, but it is generally very limited in scope. Few studies have been undertaken that draw upon a cultural-historical reading of inclusive pedagogy, and even less in the area of science education. In addition, we know next to nothing about the science learning of preschool children with visual impairment using cultural-historical theory. This paper seeks to fill this gap by presenting a study of one child with Albinism who participated in a unit of early childhood science where fairy tales were used for learning about the concepts of sound and growth. This paper reports upon the social and material conditions that were created to support learning in the preschool, whilst also examining how the learning of growth and sound were supported at home. The study found three new pedagogical features for inclusion: Imagination in science; Ongoing scientific narrative; and Scientific mirroring. It was found that when a dialectical reading of home and centre practices feature, greater insights into inclusive pedagogy for science learning are afforded, and a view of science as a collective enterprise emerges. It is argued that a cultural-historical conception of inclusion demands that the social conditions, rather than the biology of the child, is foregrounded, and through this greater insights into how science learning for children with visual impairment is gained.

  10. Indecisiveness aversion and preference for commitment

    OpenAIRE

    Danan, Eric; Guerdjikova, Ani; Zimper, Alexander

    2012-01-01

    International audience; We present an axiomatic model of preferences over menus that is motivated by three assumptions. First, the decision maker is uncertain ex ante (i.e., at the time of choosing a menu) about her ex post (i.e., at the time of choosing an option within her chosen menu) preferences over options, and she anticipates that this subjective uncertainty will not resolve before the ex post stage. Second, she is averse to ex post indecisiveness (i.e., to having to choose between opt...

  11. State-dependent interaction in the antihistamine-induced disruption of a radiation-induced conditioned taste aversion

    Energy Technology Data Exchange (ETDEWEB)

    Rabin, B.M. (Armed Forces Radiobiology Research Inst., Bethesda, MD); Hunt, W.A.; Lee, J.

    1982-06-01

    Two experiments were run to evaluate the possibility that injection of antihistamine can produce a state-dependent acquisition of a radiation-induced conditioned taste aversion. In the first experiment, pretreating rats with the antihistamine chlorpheniramine maleate prior to their initial exposure to sucrose and to low-level irradiation on the conditioning day did not prevent the acquisition of a taste aversion to sucrose when the antihistamine was also administered prior to a subsequent preference test. In the second experiment, rats were both conditioned and tested for a radiation-induced aversion in a drug-free state. Under these condtions, the rats continued to show an aversion to sucrose despite pretreating them with chlorpheniramine prior to irradiation. Since rats conditioned under the antihistamine do not show the radiation-induced conditioned taste aversion when tested for sucrose preference in a nondrug state, it would seem that pretreating rats with an antihistamine prior to conditioning affects only the retrieval of the previously learned response and not its acquisition.

  12. Understanding ill-structured engineering ethics problems through a collaborative learning and argument visualization approach.

    Science.gov (United States)

    Hoffmann, Michael; Borenstein, Jason

    2014-03-01

    As a committee of the National Academy of Engineering recognized, ethics education should foster the ability of students to analyze complex decision situations and ill-structured problems. Building on the NAE's insights, we report about an innovative teaching approach that has two main features: first, it places the emphasis on deliberation and on self-directed, problem-based learning in small groups of students; and second, it focuses on understanding ill-structured problems. The first innovation is motivated by an abundance of scholarly research that supports the value of deliberative learning practices. The second results from a critique of the traditional case-study approach in engineering ethics. A key problem with standard cases is that they are usually described in such a fashion that renders the ethical problem as being too obvious and simplistic. The practitioner, by contrast, may face problems that are ill-structured. In the collaborative learning environment described here, groups of students use interactive and web-based argument visualization software called "AGORA-net: Participate - Deliberate!". The function of the software is to structure communication and problem solving in small groups. Students are confronted with the task of identifying possible stakeholder positions and reconstructing their legitimacy by constructing justifications for these positions in the form of graphically represented argument maps. The argument maps are then presented in class so that these stakeholder positions and their respective justifications become visible and can be brought into a reasoned dialogue. Argument mapping provides an opportunity for students to collaborate in teams and to develop critical thinking and argumentation skills.

  13. Collaboration Between Student Art Teachers and Communication and Digital Media Students Promoting Subject Specific Didactics in Digital Visual Learning Design

    DEFF Research Database (Denmark)

    Buhl, Mie; Skov, Kirsten

    . Student art teachers and teacher trainers took part in the design process performed by communication students. The project took its point of the departure in the act of Danish teacher education where student teachers must be educated in the practical use of digital visual media for art practices aiming...... at achieving the necessary competences to teach visual arts in school. This, however, challenges both student teachers as well as their lecturers in how to use digital media for doing artwork that goes beyond the well-known re-mediations (image processing or editing programs) of traditional media like painting......, drawing or video. Thus, the project suggested the development of a visual learning design for achieving augmented reality (AR) experiences in urban environments and sharing them on social media. The purpose was to explore adequate approaches to work with digital media in visual arts education based...

  14. Impact of online visual feedback on motor acquisition and retention when learning to reach in a force field.

    Science.gov (United States)

    Batcho, C S; Gagné, M; Bouyer, L J; Roy, J S; Mercier, C

    2016-11-19

    When subjects learn a novel motor task, several sources of feedback (proprioceptive, visual or auditory) contribute to the performance. Over the past few years, several studies have investigated the role of visual feedback in motor learning, yet evidence remains conflicting. The aim of this study was therefore to investigate the role of online visual feedback (VFb) on the acquisition and retention stages of motor learning associated with training in a reaching task. Thirty healthy subjects made ballistic reaching movements with their dominant arm toward two targets, on 2 consecutive days using a robotized exoskeleton (KINARM). They were randomly assigned to a group with (VFb) or without (NoVFb) VFb of index position during movement. On day 1, the task was performed before (baseline) and during the application of a velocity-dependent resistive force field (adaptation). To assess retention, participants repeated the task with the force field on day 2. Motor learning was characterized by: (1) the final endpoint error (movement accuracy) and (2) the initial angle (iANG) of deviation (motor planning). Even though both groups showed motor adaptation, the NoVFb-group exhibited slower learning and higher final endpoint error than the VFb-group. In some condition, subjects trained without visual feedback used more curved initial trajectories to anticipate for the perturbation. This observation suggests that learning to reach targets in a velocity-dependent resistive force field is possible even when feedback is limited. However, the absence of VFb leads to different strategies that were only apparent when reaching toward the most challenging target.

  15. Neural correlates of aversive conditioning: development of a functional imaging paradigm for the investigation of anxiety disorders.

    Science.gov (United States)

    Reinhardt, Isabelle; Jansen, Andreas; Kellermann, Thilo; Schüppen, André; Kohn, Nils; Gerlach, Alexander L; Kircher, Tilo

    2010-09-01

    The purpose of the present study was to establish a short paradigm for the examination of classical aversive conditioning processes for application in patients with anxiety disorders. We measured behavioral, autonomic and neural correlates of the paradigm in healthy subjects, applying functional magnetic resonance imaging (fMRI) and measurement of skin conductance. Therefore, neutral visual stimuli were paired with an unpleasant white noise as unconditioned stimulus. Twenty healthy subjects performed three experimental phases of learning: familiarization, acquisition and extinction. Subjective ratings of valence and arousal after each phase of conditioning as well as skin conductance measurement indicated successful conditioning. During acquisition, fMRI results showed increased activation for the conditioned stimulus (CS+(unpaired)) when compared with the non-conditioned stimulus (CS-) in the right amygdala, the insulae, the anterior cingulate cortex and the parahippocampal gyrus, all regions known to be involved in emotional processing. In addition, a linearly decreasing activation in the right amygdala/hippocampus for the CS- across the acquisition phase was found. There were no significant differences between CS+ and CS- during extinction. In conclusion, the applicability of this paradigm for the evaluation of neural correlates in conditioning and extinction processes has been proven. Thus, we present a promising paradigm for the examination of the fear-circuit in patients with anxiety disorders and additionally effects of cognitive-behavioral interventions.

  16. Acute stress affects risk taking but not ambiguity aversion

    Science.gov (United States)

    Buckert, Magdalena; Schwieren, Christiane; Kudielka, Brigitte M.; Fiebach, Christian J.

    2014-01-01

    Economic decisions are often made in stressful situations (e.g., at the trading floor), but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity) using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups), we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26). Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect. PMID:24834024

  17. Acute stress affects risk taking but not ambiguity aversion.

    Science.gov (United States)

    Buckert, Magdalena; Schwieren, Christiane; Kudielka, Brigitte M; Fiebach, Christian J

    2014-01-01

    Economic decisions are often made in stressful situations (e.g., at the trading floor), but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity) using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups), we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26). Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect.

  18. Acute stress affects risk taking but not ambiguity aversion

    Directory of Open Access Journals (Sweden)

    Magdalena eBuckert

    2014-05-01

    Full Text Available Economic decisions are often made in stressful situations (e.g., at the trading floor, but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups, we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26. Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect.

  19. Some aversive characteristics of centrifugally generated gravity.

    Science.gov (United States)

    Altman, F.

    1973-01-01

    The effective weight of rats was manipulated by centrifugation. Two effective weight levels were obtained. In three escape avoidance conditions a lever press produced a change from a base level of 2.1 g to a response level of 1.1 g. In a punishment condition a response produced a change from a 1.1 g level to a 2.1 g level and in an extinction condition responses had no effect on the 2.1 g effective weight level present. All changes took 30 sec and were maintained for an additional 10 sec before a return to base level was initiated. When responses occurred closer together than the 40 sec, they delayed the return to base level by 40 sec. This 40 sec interval is referred to as response-contingent-time. The response rate and amount of response-contingent-time served as the data. The results confirmed previous data that centrifugation is aversive. The results are interpreted as indicating that the aversiveness is attributable to the increase in effective weight, and that rats can discriminate the different angular velocity-radius of rotation combinations used.

  20. Does ambiguity aversion survive in experimental asset markets?

    NARCIS (Netherlands)

    Füllbrunn, Sascha; Rau, Holger A.; Weitzel, Utz

    2014-01-01

    Although a number of theoretical studies explain empirical puzzles in finance with ambiguity aversion, it is not a given that individual ambiguity attitudes survive in markets. In fact, despite ample evidence of ambiguity aversion in individual decision making, most studies find no or only limited a

  1. Does ambiguity aversion survive in experimental asset markets?

    NARCIS (Netherlands)

    Füllbrunn, S.C.; Rau, H.; Weitzel, G.U.

    2014-01-01

    Although a number of theoretical studies explain empirical puzzles in finance with ambi-guity aversion, it is not a given that individual ambiguity attitudes survive in markets. Infact, despite ample evidence of ambiguity aversion in individual decision making, moststudies find no or only limited am

  2. Modeling non-monotone risk aversion using SAHARA utility functions

    NARCIS (Netherlands)

    A. Chen; A. Pelsser; M. Vellekoop

    2011-01-01

    We develop a new class of utility functions, SAHARA utility, with the distinguishing feature that it allows absolute risk aversion to be non-monotone and implements the assumption that agents may become less risk averse for very low values of wealth. The class contains the well-known exponential and

  3. Appetitive and aversive classical conditioning of female sexual response

    NARCIS (Netherlands)

    S. Both; E. Laan; M. Spiering; T. Nilsson; S. Oomens; W. Everaerd

    2008-01-01

    INTRODUCTION: There is only limited evidence for appetitive classical conditioning of female sexual response, and to date modulation of female sexual response by aversive conditioning has not been studied. AIM: The aim of this article is to study appetitive and aversive classical conditioning of sex

  4. The intensity of a fetal taste aversion is modulated by the anesthesia used during conditioning.

    Science.gov (United States)

    Mickley, G A; Lovelace, J D; Farrell, S T; Chang, K S

    1995-03-16

    Rat fetuses (E18) can learn a taste aversion in utero if experience with a sweet flavor (saccharin = Sac) is followed by a malaise-producing injection of lithium chloride (LiCl). Here we report that this phenomenon can be significantly modulated by the type of anesthesia administered to the pregnant dam before the conditioning procedure. Dams were anesthetized with one of the following drugs or drug combinations: (1) sodium pentobarbital; (2) ketamine hydrochloride and xylazine; or (3) sodium pentobarbital and ketamine hydrochloride. While under the influence of these anesthetics, rat fetuses received pairings of Sac + LiCl or one of the following sets of oral and systemic (i.p.) control injections: Sac + Saline, H2O + LiCl; H2O + Saline. At age 15 days neonatal rats were given a taste preference test by allowing them to select nipples painted with either saccharin or vehicle (H2O). After weaning, rats were given an additional taste preference test where they were allowed to drink from bottles filled with either 0.30% saccharin or water. Neonates that received Sac + LiCl injections avoided saccharin-painted nipples while neonates that received control injections in utero preferred saccharin-painted nipples. Rats that acquired the taste aversion under the influence of ketamine showed a significantly stronger conditioned taste aversion on the nipple preference test than did those from dams injected with sodium pentobarbital. The conditioned taste aversion was not detectable later during the bottle preference test. Since ketamine blocks N-methyl-D-aspartate (NMDA) glutamate receptors, and these receptors have been implicated in neural plasticity during development, our data suggest that NMDA antagonism can potentiate fetal learning. Ketamine has been used as an obstetrical and pediatric anesthetic.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Rapid prefrontal cortex activation towards aversively paired faces and enhanced contingency detection are observed in highly trait-anxious women under challenging conditions

    Directory of Open Access Journals (Sweden)

    Maimu Alissa Rehbein

    2015-06-01

    Full Text Available Relative to healthy controls, anxiety-disorder patients show anomalies in classical conditioning that may either result from, or provide a risk factor for, clinically relevant anxiety. Here, we investigated whether healthy participants with enhanced anxiety vulnerability show abnormalities in a challenging affective-conditioning paradigm, in which many stimulus-reinforcer associations had to be acquired with only few learning trials. Forty-seven high and low trait-anxious females underwent MultiCS conditioning, in which 52 different neutral faces (CS+ were paired with an aversive noise (US, while further 52 faces (CS- remained unpaired. Emotional learning was assessed by evaluative (rating, behavioral (dot-probe, contingency report, and neurophysiological (magnetoencephalography measures before, during, and after learning. High and low trait-anxious groups did not differ in evaluative ratings or response priming before or after conditioning. High trait-anxious women, however, were better than low trait-anxious women at reporting CS+/US contingencies after conditioning, and showed an enhanced prefrontal cortex activation towards CS+ in the M1 (i.e., 80 to 117 ms and M170 time intervals (i.e., 140 to 160 ms during acquisition. These effects in MultiCS conditioning observed in individuals with elevated trait anxiety are consistent with theories of enhanced conditionability in anxiety vulnerability. Furthermore, they point towards increased threat monitoring and detection in highly trait-anxious females, possibly mediated by alterations in visual working memory.

  6. Spatio-temporal auxiliary particle filtering with l1-norm-based appearance model learning for robust visual tracking.

    Science.gov (United States)

    Kim, Du Yong; Jeon, Moongu

    2013-02-01

    In this paper, we propose an efficient and accurate visual tracker equipped with a new particle filtering algorithm and robust subspace learning-based appearance model. The proposed visual tracker avoids drifting problems caused by abrupt motion changes and severe appearance variations that are well-known difficulties in visual tracking. The proposed algorithm is based on a type of auxiliary particle filtering that uses a spatio-temporal sliding window. Compared to conventional particle filtering algorithms, spatio-temporal auxiliary particle filtering is computationally efficient and successfully implemented in visual tracking. In addition, a real-time robust principal component pursuit (RRPCP) equipped with l(1)-norm optimization has been utilized to obtain a new appearance model learning block for reliable visual tracking especially for occlusions in object appearance. The overall tracking framework based on the dual ideas is robust against occlusions and out-of-plane motions because of the proposed spatio-temporal filtering and recursive form of RRPCP. The designed tracker has been evaluated using challenging video sequences, and the results confirm the advantage of using this tracker.

  7. Enhanced striatal sensitivity to aversive reinforcement in adolescents versus adults.

    Science.gov (United States)

    Galván, Adriana; McGlennen, Kristine M

    2013-02-01

    Neurodevelopmental changes in mesolimbic regions are associated with adolescent risk-taking behavior. Numerous studies have shown exaggerated activation in the striatum in adolescents compared with children and adults during reward processing. However, striatal sensitivity to aversion remains elusive. Given the important role of the striatum in tracking both appetitive and aversive events, addressing this question is critical to understanding adolescent decision-making, as both positive and negative factors contribute to this behavior. In this study, human adult and adolescent participants performed a task in which they received squirts of appetitive or aversive liquid while undergoing fMRI, a novel approach in human adolescents. Compared with adults, adolescents showed greater behavioral and striatal sensitivity to both appetitive and aversive stimuli, an effect that was exaggerated in response to delivery of the aversive stimulus. Collectively, these findings contribute to understanding how neural responses to positive and negative outcomes differ between adolescents and adults and how they may influence adolescent behavior.

  8. Exploring Middle School Students' Representational Competence in Science: Development and Verification of a Framework for Learning with Visual Representations

    Science.gov (United States)

    Tippett, Christine Diane

    Scientific knowledge is constructed and communicated through a range of forms in addition to verbal language. Maps, graphs, charts, diagrams, formulae, models, and drawings are just some of the ways in which science concepts can be represented. Representational competence---an aspect of visual literacy that focuses on the ability to interpret, transform, and produce visual representations---is a key component of science literacy and an essential part of science reading and writing. To date, however, most research has examined learning from representations rather than learning with representations. This dissertation consisted of three distinct projects that were related by a common focus on learning from visual representations as an important aspect of scientific literacy. The first project was the development of an exploratory framework that is proposed for use in investigations of students constructing and interpreting multimedia texts. The exploratory framework, which integrates cognition, metacognition, semiotics, and systemic functional linguistics, could eventually result in a model that might be used to guide classroom practice, leading to improved visual literacy, better comprehension of science concepts, and enhanced science literacy because it emphasizes distinct aspects of learning with representations that can be addressed though explicit instruction. The second project was a metasynthesis of the research that was previously conducted as part of the Explicit Literacy Instruction Embedded in Middle School Science project (Pacific CRYSTAL, http://www.educ.uvic.ca/pacificcrystal). Five overarching themes emerged from this case-to-case synthesis: the engaging and effective nature of multimedia genres, opportunities for differentiated instruction using multimodal strategies, opportunities for assessment, an emphasis on visual representations, and the robustness of some multimodal literacy strategies across content areas. The third project was a mixed

  9. The Importance of Visual Feedback Design in BCIs; from Embodiment to Motor Imagery Learning

    Science.gov (United States)

    Alimardani, Maryam; Nishio, Shuichi; Ishiguro, Hiroshi

    2016-01-01

    Brain computer interfaces (BCIs) have been developed and implemented in many areas as a new communication channel between the human brain and external devices. Despite their rapid growth and broad popularity, the inaccurate performance and cost of user-training are yet the main issues that prevent their application out of the research and clinical environment. We previously introduced a BCI system for the control of a very humanlike android that could raise a sense of embodiment and agency in the operators only by imagining a movement (motor imagery) and watching the robot perform it. Also using the same setup, we further discovered that the positive bias of subjects’ performance both increased their sensation of embodiment and improved their motor imagery skills in a short period. In this work, we studied the shared mechanism between the experience of embodiment and motor imagery. We compared the trend of motor imagery learning when two groups of subjects BCI-operated different looking robots, a very humanlike android’s hands and a pair of metallic gripper. Although our experiments did not show a significant change of learning between the two groups immediately during one session, the android group revealed better motor imagery skills in the follow up session when both groups repeated the task using the non-humanlike gripper. This result shows that motor imagery skills learnt during the BCI-operation of humanlike hands are more robust to time and visual feedback changes. We discuss the role of embodiment and mirror neuron system in such outcome and propose the application of androids for efficient BCI training. PMID:27598310

  10. The Importance of Visual Feedback Design in BCIs; from Embodiment to Motor Imagery Learning.

    Science.gov (United States)

    Alimardani, Maryam; Nishio, Shuichi; Ishiguro, Hiroshi

    2016-01-01

    Brain computer interfaces (BCIs) have been developed and implemented in many areas as a new communication channel between the human brain and external devices. Despite their rapid growth and broad popularity, the inaccurate performance and cost of user-training are yet the main issues that prevent their application out of the research and clinical environment. We previously introduced a BCI system for the control of a very humanlike android that could raise a sense of embodiment and agency in the operators only by imagining a movement (motor imagery) and watching the robot perform it. Also using the same setup, we further discovered that the positive bias of subjects' performance both increased their sensation of embodiment and improved their motor imagery skills in a short period. In this work, we studied the shared mechanism between the experience of embodiment and motor imagery. We compared the trend of motor imagery learning when two groups of subjects BCI-operated different looking robots, a very humanlike android's hands and a pair of metallic gripper. Although our experiments did not show a significant change of learning between the two groups immediately during one session, the android group revealed better motor imagery skills in the follow up session when both groups repeated the task using the non-humanlike gripper. This result shows that motor imagery skills learnt during the BCI-operation of humanlike hands are more robust to time and visual feedback changes. We discuss the role of embodiment and mirror neuron system in such outcome and propose the application of androids for efficient BCI training.

  11. Impact of distance-based metric learning on classification and visualization model performance and structure-activity landscapes

    Science.gov (United States)

    Kireeva, Natalia V.; Ovchinnikova, Svetlana I.; Kuznetsov, Sergey L.; Kazennov, Andrey M.; Tsivadze, Aslan Yu.

    2014-02-01

    This study concerns large margin nearest neighbors classifier and its multi-metric extension as the efficient approaches for metric learning which aimed to learn an appropriate distance/similarity function for considered case studies. In recent years, many studies in data mining and pattern recognition have demonstrated that a learned metric can significantly improve the performance in classification, clustering and retrieval tasks. The paper describes application of the metric learning approach to in silico assessment of chemical liabilities. Chemical liabilities, such as adverse effects and toxicity, play a significant role in drug discovery process, in silico assessment of chemical liabilities is an important step aimed to reduce costs and animal testing by complementing or replacing in vitro and in vivo experiments. Here, to our knowledge for the first time, a distance-based metric learning procedures have been applied for in silico assessment of chemical liabilities, the impact of metric learning on structure-activity landscapes and predictive performance of developed models has been analyzed, the learned metric was used in support vector machines. The metric learning results have been illustrated using linear and non-linear data visualization techniques in order to indicate how the change of metrics affected nearest neighbors relations and descriptor space.

  12. [Dependence of learning characteristics on visual object properties in Rhesus macaca by bilateral removal of the 7th field of the parietal cortex].

    Science.gov (United States)

    Dudkin, K N; Chueva, I V; Makarov, F N; Orlov, I V

    1998-03-01

    Removal of the rhesus monkey parietal cortex 7th field exerted no effect on learning processes involving visual discrimination of images united in their colour and geometrical form, but the learning of differentiating the spatial information did suffer. The data obtained suggests that, in the process of learning visual differentiation, spatial differentiating signs are formed, the process involving neuronal structures of the 7th field of the inferior cortex. Removal of the 7th field disrupts mechanisms of the body scheme assession and egocentric orientation resulting from visual-vestibular interrelationships.

  13. Statistical learning of serial visual transitions by neurons in monkey inferotemporal cortex.

    Science.gov (United States)

    Meyer, Travis; Ramachandran, Suchitra; Olson, Carl R

    2014-07-09

    If monkeys repeatedly, over the course of weeks, view displays in which two images appear in fixed sequence, then neurons of inferotemporal cortex (ITC) come to exhibit prediction suppression. The response to the trailing image is weaker if it follows the leading image with which it was paired during training than if it follows some other leading image. Prediction suppression is a plausible neural mechanism for statistical learning of visual transitions such as has been demonstrated in behavioral studies of human infants and adults. However, in the human studies, subjects are exposed to continuous sequences in which the same image can be both predicted and predicting and statistical dependency can exist between nonadjacent items. The aim of the present study was to investigate whether prediction suppression in ITC develops under such circumstances. To resolve this issue, we exposed monkeys repeatedly to triplets of images presented in fixed order. The results indicate that prediction suppression can be induced by training not only with pairs of images but also with longer sequences.

  14. Neuronal mechanisms for pain-induced aversion behavioral studies using a conditioned place aversion test.

    Science.gov (United States)

    Minami, Masabumi

    2009-01-01

    Pain consists of sensory discriminative and negative affective components. Although the neural systems responsible for the sensory component of pain have been studied extensively, the neural basis of the affective component is not well understood. Recently, behavioral studies using conditioned place aversion (CPA) tests have successfully elucidated the neural circuits and mechanisms underlying the negative affective component of pain. Excitotoxic lesions of the anterior cingulate cortex (ACC), central amygdaloid nucleus, basolateral amygdaloid nucleus (BLA), or bed nucleus of the stria terminalis (BNST) suppressed intraplantar formalin-induced aversive responses. Glutamatergic transmission within the ACC and BLA via NMDA receptors was shown to play a critical role in the affective component of pain. In the BNST, especially its ventral part, noradrenergic transmission via beta-adrenergic receptors was demonstrated as important for pain-induced aversion. Because persistent pain is frequently associated with psychological and emotional dysfunction, studies of the neural circuits and the molecular mechanisms involved in the affective component of pain may have considerable clinical importance in the treatment of chronic pain.

  15. A Theoretical Analysis of How Segmentation of Dynamic Visualizations Optimizes Students' Learning

    NARCIS (Netherlands)

    I.A.E. Spanjers; T.A.J.M. van Gog (Tamara); J.J.G. van Merriënboer (Jeroen)

    2010-01-01

    textabstractThis article reviews studies investigating segmentation of dynamic visualizations (i.e., showing dynamic visualizations in pieces with pauses in between) and discusses two not mutually exclusive processes that might underlie the effectiveness of segmentation. First, cognitive activities

  16. Visual environment, attention allocation, and learning in young children: when too much of a good thing may be bad.

    Science.gov (United States)

    Fisher, Anna V; Godwin, Karrie E; Seltman, Howard

    2014-07-01

    A large body of evidence supports the importance of focused attention for encoding and task performance. Yet young children with immature regulation of focused attention are often placed in elementary-school classrooms containing many displays that are not relevant to ongoing instruction. We investigated whether such displays can affect children's ability to maintain focused attention during instruction and to learn the lesson content. We placed kindergarten children in a laboratory classroom for six introductory science lessons, and we experimentally manipulated the visual environment in the classroom. Children were more distracted by the visual environment, spent more time off task, and demonstrated smaller learning gains when the walls were highly decorated than when the decorations were removed.

  17. Reversible inactivation of dorsal hippocampus by tetrodotoxin impairs blocking of taste aversion selectively during the acquisition but not the retrieval in rats.

    Science.gov (United States)

    Gallo, M; Cándido, A

    1995-02-15

    The role of the dorsal hippocampus in the different stages of blocking was examined in a taste aversion learning task. Blocking is a learning effect in which one previously conditioned element of a compound makes the conditioning of the added element difficult. An effective blocking procedure with one trial in each stage was tested in unoperated rats. In the first stage, rats drank saccharin and later received lithium chloride by i.p. injection. In the second stage, they were presented with a serial compound saccharin-cider vinegar before lithium injection. In a one-bottle, test a reduced aversion to cider vinegar was observed in this group compared to control groups with no previous saccharin aversion. Bilateral tetrodotoxin (TTX) injection (10 ng/microliters) in the dorsal hippocampus attenuated blocking if this was applied before drinking the compound stimulus during the second stage, but it produced no effect applied either before drinking saccharin in the first stage or before testing. Non-specific retrieval deficit produced by TTX injection applied before testing was ruled out in a control group subjected to a conventional cider vinegar aversion learning which showed complete retrieval of the aversion under TTX. It is concluded that the hippocampal function relevant for blocking takes place during the compound phase.

  18. Loss aversion and 5HTT gene variants in adolescent anxiety

    Directory of Open Access Journals (Sweden)

    Monique Ernst

    2014-04-01

    Full Text Available Loss aversion, a well-documented behavioral phenomenon, characterizes decisions under risk in adult populations. As such, loss aversion may provide a reliable measure of risky behavior. Surprisingly, little is known about loss aversion in adolescents, a group who manifests risk-taking behavior, or in anxiety disorders, which are associated with risk-avoidance. Finally, loss aversion is expected to be modulated by genotype, particularly the serotonin transporter (SERT gene variant, based on its role in anxiety and impulsivity. This genetic modulation may also differ between anxious and healthy adolescents, given their distinct propensities for risk taking. The present work examines the modulation of loss aversion, an index of risk-taking, and reaction-time to decision, an index of impulsivity, by the serotonin-transporter-gene-linked polymorphisms (5HTTLPR in healthy and clinically anxious adolescents. Findings show that loss aversion (1 does manifest in adolescents, (2 does not differ between healthy and clinically anxious participants, and (3, when stratified by SERT genotype, identifies a subset of anxious adolescents who are high SERT-expressers, and show excessively low loss-aversion and high impulsivity. This last finding may serve as preliminary evidence for 5HTTLPR as a risk factor for the development of comorbid disorders associated with risk-taking and impulsivity in clinically anxious adolescents.

  19. An Expanded Framework for Biomolecular Visualization in the Classroom: Learning Goals and Competencies

    Science.gov (United States)

    Dries, Daniel R.; Dean, Diane M.; Listenberger, Laura L.; Novak, Walter R. P.; Franzen, Margaret A.; Craig, Paul A.

    2017-01-01

    A thorough understanding of the molecular biosciences requires the ability to visualize and manipulate molecules in order to interpret results or to generate hypotheses. While many instructors in biochemistry and molecular biology use visual representations, few indicate that they explicitly teach visual literacy. One reason is the need for a list…

  20. Visual Literacy Standards in Higher Education: New Opportunities for Libraries and Student Learning

    Science.gov (United States)

    Hattwig, Denise; Bussert, Kaila; Medaille, Ann; Burgess, Joanna

    2013-01-01

    Visual literacy is essential for 21st century learners. Across the higher education curriculum, students are being asked to use and produce images and visual media in their academic work, and they must be prepared to do so. The Association of College and Research Libraries has published the "Visual Literacy Competency Standards for Higher…