Greater Disruption Due to Failure of Inhibitory Control on an Ambiguous Distractor

Considerable evidence indicates that a stimulus that is subthreshold, and thus consciously invisible, influences brain activity and behavioral performance. However, it is not clear how subthreshold stimuli are processed in the brain. We found that a task-irrelevant subthreshold coherent motion led to a stronger disturbance in task performance than did suprathreshold motion. With the subthreshold motion, activity in the visual cortex measured by functional magnetic resonance imaging was higher, but activity in the lateral prefrontal cortex was lower, than with suprathreshold motion. These results suggest that subthreshold irrelevant signals are not subject to effective inhibitory control

Model-free two-step design for improving transient learning performance in nonlinear optimal regulator problems

Reinforcement learning (RL) provides a model-free approach to designing an optimal controller for nonlinear dynamical systems. However, the learning process requires a considerable number of trial-and-error experiments using the poorly controlled system, and accumulates wear and tear on the plant. Thus, it is desirable to maintain some degree of control performance during the learning process. In this paper, we propose a model-free two-step design approach to improve the transient learning performance of RL in an optimal regulator design problem for unknown nonlinear systems. Specifically, a linear control law pre-designed in a model-free manner is used in parallel with online RL to ensure a certain level of performance at the early stage of learning. Numerical simulations show that the proposed method improves the transient learning performance and efficiency in hyperparameter tuning of RL

Interference and feature specificity in visual perceptual learning

AbstractPerceptual learning (PL) often shows specificity to a trained feature. We investigated whether feature specificity is related to disruption in PL using the texture discrimination task (TDT), which shows learning specificity to background element but not to target element. Learning was disrupted when orientations of background elements were changed in two successive training sessions (interference) but not in a random order from trial to trial (roving). The presentation of target elements seemed to have reversed effect; learning occurred in two-parts training but not with roving. These results suggest that interference in TDT is feature specific while disruption by roving is not

Location-Specific Cortical Activation Changes during Sleep after Training for Perceptual Learning

Visual perceptual learning is defined as performance enhancement on a sensory task and is distinguished from other types of learning and memory in that it is highly specific for location of the trained stimulus. The location specificity has been shown to be paralleled by enhancement in functional magnetic resonance imaging (fMRI) signal in the trained region of V1 after visual training. Although recently the role of sleep in strengthening visual perceptual learning has attracted much attention, its underlying neural mechanism has yet to be clarified. Here, for the first time, fMRI measurement of human V1 activation was conducted concurrently with a polysomnogram during sleep with and without preceding training for visual perceptual learning. As a result of predetermined region-of-interest analysis of V1, activation enhancement during non-rapid-eye-movement sleep after training was observed specifically in the trained region of V1. Furthermore, improvement of task performance measured subsequently to the post-training sleep session was significantly correlated with the amount of the trained-region-specific fMRI activation in V1 during sleep. These results suggest that as far as V1 is concerned, only the trained region is involved in improving task performance after sleep

Metallic Pattern Fabrication in Organic Mott Insulating Crystal by Local X-Ray Irradiation

We have fabricated a metallic structure in an organic Mott insulator $\kappa$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Cl. The periodic metallic domains of approximately 90$\times$90 $\mu$m$^2$ obtained by X-ray irradiation through a molybdenum mesh mask are visualized by scanning microregion infrared reflectance spectroscopy technique. No deterioration by irradiation is found in a range of nanometer to micrometer scales. We demonstrate that the present processing method is applicable for the fabrication of molecular electronic devices.Comment: 3 pages, submitted to APE

Lesson Study Consulting for the Professional Development of Textbook Developers: A case of social studies textbook development project for the Ministry of Education, Youth and Sport in Cambodia

Who should disseminate new curriculum and textbooks from the central government to classroom in developing countries? And, how is it possible? Curriculum and textbook developers often faces the necessity of and the challenges in spreading the essentials and intention of new curriculum and textbooks and the expected educational practices to classroom. In order to design and implement consistent educational reform through three layers of the curriculum (the intended, the implemented and the attained level), it is required for them to be committed in not only the development stage with a clear picture of quality teaching and learning, but also the dissemination stage through in-service teacher training such as lesson study. This study aims at clarifying potential measures to develop the expertise for curriculum and textbook developers as a communicator of educational reform in developing countries. In the process of our project on the curriculum and textbook development of social studies education in Cambodia, we assume “the expertise of consulting lesson study” and examine it both from theory and practical cases of (i) lesson-demonstrating approach and (ii) lesson-advising approach. As a consequence, it is found that their ability for consulting lesson study could be enhanced by regarding senior (Japanese) experts as a role model. And also, the result implies that, for their continuous professional development, it is necessary for them to purposefully take part in lesson study consulting, and shift the approach from “modeling” to “coaching” by steps