Hidetsugu Asano

Large-Scale Somatotopic Refinement via Functional Synapse Elimination in the Sensory Thalamus of Developing Mice

Functional synapse elimination and strengthening are crucial developmental processes in the formation of precise neuronal circuits in the somatosensory system, but the underlying alterations in topographical organization are not yet fully understood. To address this issue, we generated transgenic mice in which afferent fibers originating from the whisker-related brain region, called the maxillary principal trigeminal nucleus (PrV2), were selectively visualized with genetically expressed fluorescent protein. We found that functional synapse elimination drove and established large-scale somatotopic refinement even after the thalamic barreloid architecture was formed. Before functional synapse elimination, the whisker sensory thalamus was innervated by afferent fibers not only from the PrV2, but also from the brainstem nuclei representing other body parts. Most notably, only afferent fibers from PrV2 onto a whisker sensory thalamic neuron selectively survived and were strengthened, whereas other afferent fibers were preferentially eliminated via their functional synapse elimination. This large-scale somatotopic refinement was at least partially dependent on somatosensory experience. These novel results uncovered a previously unrecognized role of developmental synapse elimination in the large-scale, instead of the fine-scale, somatotopic refinement even after the initial segregation of the barreloid map.

Detection of small-waving hand by distributed camera system

This paper proposes a method to detect small-waving hand from image sequences. The method is based on frequency analysis of intensity value change for each pixel of low-resolution images converted from input images. Handwaving makes periodical change of intensity value of image pixels located in the moving region. The periodical change is detected by thresholding of a value accumulating frequency features obtained through FFT calculation. The proposed method can stably detect small-waving hand with 3-5 Hz in a range of 2-6 m. We demonstrate an application of spatial memory through measuring 3D position of small-waving hand detected by a distributed camera system.

Hand waving in command spaces: a framework for operating home appliances

ABSTRACT In this paper, hand waving in a ‘command space’ is proposed as a new framework for operating home appliances. A command space is associated with the operation of a home appliance; an operation is retrieved by waving a hand in the command space. A home appliance operation system with the function of multiplexing command space modules and integrating multiple commands is constructed. With the proposed framework and system, home appliance operation is possible only by hand waving, an intuitive gesture for a human. Experiments were conducted that verified that complex operations, such as scheduling the recording of a TV program, can be performed with the system. The usability of the constructed system is evaluated using Brookes System Usability Scale (SUS). The average SUS score was 66.8, which indicates that the subjects had relatively positive impression on the system in spite of long operation time. GRAPHICAL ABSTRACT

Mouth Movement Recognition Using Template Matching and its Implementation in an Intelligent Room

This paper proposes a method of recognizing movements of the mouth from images and implements the method in an intelligent room. The proposed method uses template matching and recognizes mouth movements for the purpose of indicating a target object in an intelligent room. First, the operator’s face is detected. Then, the mouth region is extracted from the facial region using the result of template matching with a template image of the lips. Dynamic Programming (DP) matching is applied to a similarity measure that is obtained by template matching. The effectiveness of the proposed method is evaluated through experiments to recognize several names of common home appliances and operations.