Hidenori Nakagawa

Pseudo-“Blindsight” Induced by Extremely Low Frequency Electromagnetic Stimulations

We investigated electromagnetic effects of phosphene as pseudo-blindsight under the influence of background colors. Five healthy male subjects ranging in age from 20 to 65 participated in the visual stimulation experiments. Concerning the frequency response characteristics of phosphene sensitivity at wavelengths 430, 530, and 560 nm (corresponding with short (S), medium (M), and long (L) wave-sensitive cone, respectively) with background light (40 l×), the sensitivities decreased by nearly one and a half times more than in the control experiment, and the threshold of the phosphene at the three wavelengths was ~22 mT on average. Furthermore, we found that electromagnetic fields of up to 40 mT might possibly affect the duration of complementary colors after a 20-s process of the blindsight-like phosphene. Our results demonstrated the possibility that pseudo-blindsight induced by electromagnetic stimulations of 40 mT at 20 Hz specifically affects retinal S-cone input, and this new knowledge may be applied as part of therapeutic eyesight exercises.

Virtual Blood-Flow Controlling System: Optimization of Human Bioactivity Under Exposure to Magnetic Fields

The purpose of this paper is to investigate the effects of extremely low-frequency magnetic fields on the nature of artificial blood solutions, using an artificial blood-circulation system. We first measured induced electromotive forces in our test fluid, using two measurement points with test equipment electrodes inserted in the flow channel near the coil surface. No significant difference in the electromotive forces at the insertion points of the electrodes could be detected. When the positions of the exposure coils were shifted a little from each other on the outside of the flow channel near two measurement points with test equipment electrodes, we were able to detect some slight differences between them. This result showed the possibility that the magnetic fields induced from the coil distinctly generated effective electromotive forces in several fluids among the artificial blood solutions. In addition, we investigated the direct-current magnetic fields for the most effective blood flow on our artificial blood-circulation system. This system may provide new knowledge about the mechanism of blood massotherapy by electromagnetic stimulations as a therapy for many diseases.

Extremely Low-Frequency Electromagnetic Control of Bloodstream on Imitative Blood-Circulation System

In this paper, we designed an artificial blood-circulation system and an original medical device for the improvement of blood flow. First, we prepared an electromagnetic flowmeter and an adaptable coil conformed to the imitative system. The sinusoidal and rectangular signals emitted were sampled with a differential amplifier. Under a constant liquid-flow rate of 7.5 L/min at the alternating electromagnetic field strength of 20 mT, we were able to obtain an induced electromotive force of approximately 2.8 mV. In addition, we investigated the potential of some frequency-changing items to act as a new life-support device for clinical applications. By modifying a commercial magnetic field machine, we designed a prototype equipped with frequency switching of 50 and 0.5 Hz to trial a cure for poor lower limb intravenous flow, lower limb edema, and venous thrombus formation. These systems may provide new knowledge about a mechanism of blood massotherapy by electromagnetic stimulations in the developments of alternating magnetic field machines.

Fundamental study of functional changes to female brain induced by pregnancy and childbirth

In this study, we investigated variations in a womens cognitive function during a time of pregnancy and childbearing. Volunteers were composed of 114 healthy women ranging in age from 23-43 years with an average age of 31.8 years (SD=4.3). Further, 79 were pregnant and 35 were not pregnant. All the pregnant women were expecting their first child and continued with the cognitive function analysis after their childbearing was concluded. We instructed the pregnant women to carry out five kinds of tests: simple reaction, SR; choice reaction, CR; working memory, WM; one card learning, OC; and divided attention, DA using card games through a cognitive function test called “CogHealth”, and compared them to a nonpregnant group. In the results of the four measurement tasks (SR, CR, WM, and DA), there were no significant differences across the three groups in the responses with the tasks. However, the response times relating to the OC learning in the postnatal women were significantly smaller, as contrasted with the times for the pregnant and the nonpregnant women (F(2,144)=4.248, P <; 0.05). Furthermore, we compared their cognitive functions between pregnant and postnatal states in corresponding volunteers in the responses with the same tasks. We also demonstrated the fact that postnatal women responded more quickly to tasks in the OC (t(32)=2.95, P <; 0.01) and the WM (t(32)=3.03, P <; 0.01) categories than responses to performing the tasks during their pregnancy. Our findings support the idea that the functions of pregnant/postnatal women are not failing, or rather postnatal women are more responsive in their reaction times with their memories by 2.7-6.2%, than the responses in both pregnant and nonpregnant women.

Functional brain measurements within the prefrontal area on pseudo-“blindsight” induced by extremely low frequency electromagnetic stimulations

We investigated electromagnetic effects of phosphene as pseudo-blindsight under the influence of background colors. Five healthy male subjects ranging in age from 20 to 65 participated in the visual stimulation experiments. Concerning the frequency response characteristics of phosphene sensitivity at wavelengths 430, 530, and 560 nm (corresponding with short (S), medium (M), and long (L) wave-sensitive cone, respectively) with background light (40 l×), the sensitivities decreased by nearly one and a half times more than in the control experiment, and the threshold of the phosphene at the three wavelengths was ~22 mT on average. Furthermore, we found that electromagnetic fields of up to 40 mT might possibly affect the duration of complementary colors after a 20-s process of the blindsight-like phosphene. Our results demonstrated the possibility that pseudo-blindsight induced by electromagnetic stimulations of 40 mT at 20 Hz specifically affects retinal S-cone input, and this new knowledge may be applied as part of therapeutic eyesight exercises.

A curious relationship between feeling level and cognitive function in female brain during pregnancy and childbearing

The purpose of this study was to investigate the correlations between feeling levels and cognitive functions in a womens brain during a time of pregnancy and childbearing. One hundred and fourteen women ranging in age from 23-43 years (mean ± SD: 31.8 ± 4.3) took part in our experiment. Seventy-nine women were pregnant (mean age ± SD: 32.1 ± 4.9) and 35 were not pregnant (mean age ± SD: 31.1 ± 4.4). All the pregnant women were expecting their first child. Concerning the pregnant group, 33 women (mean age ± SD: 32.0 ± 4.0) continued with our experiment after their childbearing was concluded. On four questionnaire categories established by Hanazawas protocol, we assessed each subjects feeling level for a child, a husband, a mood and their health. At the same time, we instructed them to carry out five kinds of tests: simple reaction, SR; choice reaction, CR; working memory, WM; one card learning, OC; and divided attention, DA using card games through a cognitive function test called “CogHealth”. The accuracies relating to the CR task in the postnatal women were significantly lower (t(18)=2.42, P <; 0.05), depending on the questionnaire scores about positive feelings for their husband. In the postnatal group, there was also an inverse correlation between their positive feelings for their child and a quick response to OC leaning (r= -0.46, P <; 0.05). Furthermore, the pregnant women who perceived that the women themselves might be in an unhealthy state were significantly higher in accuracy for the DA task among the five CogHealth tasks than pregnant women who believed their health was sound (t(77)=2.00, P <; 0.05). There were also no significant differences between subjects who considered themselves healthy and those who considered themselves unhealthy in each of the other two groups. Our findings confirm that pregnant and postnatal womens feeling levels are closely connected with their cognitive functions.

Conscious Perception of Color in Pseudo-“Blindsight”

In this paper, we designed a new coil system for extremely low-frequency electromagnetic stimuli of 40 mT at 20 Hz and investigated an electromagnetic control of the human color perceptions on durations of complementary colors. Although reductions in the duration were found for all the retinal cone photoreceptor cells (short (S), medium, and long wave-sensitive cones), a distinct reduction with an order of degree of 12.5% was observed in S-cone input. Furthermore, we investigated the effects of the stimuli at the very limit of the threshold for a phosphene like blindsight on durations of complementary colors. The results showed the fact that even a comparatively weak stimulus of 10 mT is able to excite retinal cone photoreceptor cells, particularly, and affect blue-sensitive (S-cone) input. We propose the idea that electromagnetic stimuli at the very limit of the threshold for a phosphene like blindsight can develop into a peculiar condition to excite these cone-cell species and gradually activate synaptic plasticity.

Sub/supraliminal stimulus with pseudo-“blindsight” under exposure to ELF fields

Objective Up to the present, some new stimulus technologies with retinal controls are needed to facilitate activations of the parietal and temporal regions via the tectal region (superior colliculus and accessory nuclei of the optic tract).

Metamorphic behaviors of T 4 -administrated Mexican axolotl under exposure to gradient magnetic field

Objective The Mexican axolotl (Ambystoma mexicanum) has been known as a precious model for regenerative capacity and postembryonic development research for a long period of time.

Magnetohydrodynamic study for magnetic therapy

Objective Recently, the development of magnetic therapies utilizing extremely low frequency (ELF) fields has been progressing gradually in the research field of biomedical engineering.