Naoko Okamoto

Visualization of children's mathematics solving process using near infrared spectroscopic approach

Over the past decade, the application of results from brain science research to education research has been a controversial topic. A NIRS imaging system shows images of Hb parameters in the brain. Measurements using NIRS are safe, easy and the equipment is portable, allowing subjects to tolerate longer research periods. The purpose of this research is to examine the characteristics of Hb using NIRS at the moment of understanding. We measured Hb in the prefrontal cortex of children while they were solving mathematical problems (tangram puzzles). As a result of the experiment, we were able to classify the children into three groups based on their solution methods. Hb continually increased in a group which could not develop a problem solving strategy for the tangram puzzles. Hb declined steadily for a group which was able to develop a strategy for the tangram puzzles. Hb was steady for a certain group that had already developed a strategy before solving the problems. Our experiments showed that the brain data from NIRS enables the visualization of childrens mathematical solution processes.

NIRS evaluates the thinking process of Mushi-kuizan task

We discuss the possibility of Near Infrared Spectroscopy (NIRS) application to the educational research. NIRS system was used for prefrontal cortex measurement of children, when they were solving Mushi-kuizan problems. The Mushi-kuizan task is one of the mathematical puzzles. Subjects were four children in fifth grade. Hemoglobin parameters such as oxygenated hemoglobin and deoxygenated hemoglobin were calculated during Mushi-kuizan problems. The parameters were compared with the performance data of each subject. Changes Hb parameters described how children use their brain. NIRS evaluated the thinking process of mathematics task. It is very useful for mathematics teachers to catch the childrens thinking process dynamically because they can consider the way of teaching for each child. It was shown that NIRS may be able to apply to education.

Spatial Pattern Formation Induced by Rapid Temperature Change in a Cholesteric Liquid Crystal

ABSTRACT We report an experimental study on a transient spatial pattern formation of a cholesteric liquid crystal, cholesteryl oleyl carbonate, induced by rapid temperature change. The spatial pattern like a network is found to be induced when the temperature is increased faster than a constant rate of 0.5 mK/s. We have measured the optical transmittance of the liquid crystal continuously during the pattern formation process and have found that the component corresponding to the network clearly appears in addition to the selective reflection of the helical structure. The observed spatial pattern is discussed in relation to the spectral shape of the transmittance.

Measurement of brain activation difference during different mathematical tasks by near infrared spectroscopy

This study examines differences in concentration changes of hemoglobin in the brain while finding algebraic solutions versus geometrical solutions. We use Near Infrared Spectroscopy imaging system to measure the hemoglobin changes while subjects are solving algebraic task and geometrical task. NIRS imaging system can measure changes in the concentration of hemoglobin. This brain activity data shows a difference between the two different experimental tasks which helps us to identify the characteristics of thinking processes.

Spatial Pattern Formation in a Cholesteric Liquid Crystal Under a Rapid Temperature Change

We have investigated the characteristic behavior of a cholesteric liquid crystal, cholesteryl oleyl carbonate, under a thermally nonequilibrium condition. It has been found that a rapid temperature increase causes the instability of the uniform planar texture, and a network-like spatial pattern is induced. We have studied this phenomenon by performing two experiments: the spectroscopic measurement of optical transmission and the dynamic light scattering measurement which proves the structural variation of the helical structure and the dynamical fluctuation of the director under the thermally equilibrium condition, respectively. We discuss the mechanism of the spatial pattern formation process by combining the results of these measurements.