94 research outputs found

    Perceptual Learning of Fine Contrast Discrimination Under Non-roving, Roving-Without-Flanker, and Roving-with-Flanker Conditions and its Relation to Neuronal Activity in Macaque V1

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    \ua9 The Author(s) 2024.Perceptual learning refers to an improvement in perceptual abilities with training. Neural signatures of visual perceptual learning have been demonstrated mostly in mid- and high-level cortical areas, while changes in early sensory cortex were often more limited. We recorded continuously from multiple neuronal clusters in area V1 while macaque monkeys learned a fine contrast categorization task. Monkeys performed the contrast discrimination task initially when a constant-contrast sample stimulus was followed by a test stimulus of variable contrast, whereby they had to indicate whether the test was of lower or higher contrast than the sample. This was followed by sessions where we employed stimulus roving; i.e. the contrast of the sample stimulus varied from trial to trial. Finally, we trained animals, under ‘stimulus roving-with-flanker’ conditions, where the test stimuli to be discriminated were flanked by ‘flanking stimuli’. Perceptual discrimination abilities improved under non-roving conditions and under roving-with-flanker conditions as training progressed. Neuronal discrimination abilities improved with training mostly under non-roving conditions, but the effect was modest and limited to the most difficult contrast. Choice probabilities, quantifying how well neural activity is correlated with choice, equally increased with training during non-roving, but not during either of the roving conditions (with and without flankers). Noise correlations changed with training in both monkeys, but the changes were not consistent between monkeys. In one monkey, noise correlations decreased with training for non-roving and both roving conditions. In the other monkey, noise correlations changed for some conditions, but lacked a systematic pattern. Thus, while perceptual learning occurred under non-roving and roving-with-flanker conditions, the changes in neural activity in V1 were overall modest and were essentially absent under the different roving conditions

    Readiness Assessment of Iran’s Insurance Industry for E-Commerce and E-Insurance Success

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    This paper attempts to develop a method for readiness assessment of potential electronic commerce (e-commerce) success of Iran’s insurance industry. This method can expand in other industries. Key factors impacting e-commerce are identified from Wells, D. and Thomann, j. (2006) researches. This model is a two-dimension 3*4 matrix. Each dimension consists of variables that influence on insurance industries readiness. These variables on horizontal dimension are: People Readiness, IT Readiness, and Business Readiness and on vertical dimension are: Business Imperative, Executive Sponsorship, Development Method and Business Process Orientation. Each cells of this matrix evaluated by 5 questions. This research’s data are collected via a 60-questions questionnaire-based survey from Iranian insurance companies. At the end of the research, the Iranian insurance companies were strongly recommended by us to invest on e-commerce and e-insurance area
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