Masanori Sakuranaga

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Extrinsic current, either pulsatile or white-noise modulated, was injected into the (cone) horizontal-cell soma and axon, and resulting responses were recorded from nearby points. In the case of white-noise inputs, signal transmission between the two points was characterized by Wiener kernels. The signal transmission within the lamina, the S-space, formed(More)
By incubating bacteria from the gut of the termite, Nasutitermes takasagoensis, in a culture medium containing a ligninic compound, direct evidence that lignin-biodegradation occurs in the gut of termites was obtained. The bacteria were capable of degrading ligninic compounds. 28% of dealkalized lignin was degraded and lignin dimer compounds, which have a(More)
The small- and large-field (cone) horizontal cells produce similar dynamic responses to a stimulus whose mean luminance is modulated by a white-noise signal. Nonlinear components increase with an increase in the mean luminance and may produce a mean square error (MSE) of up to 15%. Increases in the mean luminance of the field stimulus bring about three(More)
Current injected into horizontal-cell somas and axons produced transient (on-off) depolarizations from type-C cells (commonly known as transient amacrine cells) similar to those produced by light. Both the light- and current-induced responses had very small linear components and nonlinear components as represented by the second-order kernels, which(More)
Responses from channel catfish type-N (sustained amacrine) cells were evoked either by step changes in illuminance, i.e. brightening or dimming from a mean illuminance, or by a white-noise modulated light stimulus. Current injected into the horizontal-cell soma or axon produced responses in type-N cells that were very similar to those produced by light(More)
Responses were evoked from ganglion cells in catfish and frog retinas by a Gaussian modulation of the mean luminance. An algorithm was devised to decompose intracellularly recorded responses into the slow and spike components and to extract the time of occurrence of a spike discharge. The dynamics of both signals were analyzed in terms of a series of(More)
Wiener's method of a nonlinear system analysis and its application to neurophysiology are surveyed. His theory is explained on the orthogonal functional series expansion of a nonlinear noise with respect to the Brownian motion whose formal derivative is understood as the white Gaussian noise. Then, efforts made for applying the method to practice are(More)
Through daily electrical stimulation of one of the hippocampi in the rabbit, EEG spikes were "kindled" in both hippocampi. Such hippocampi (termed kindled hippocampi) were then studied with the microelectrode in acute experiments. The electrical activities of the kindled hippocampus were characterized by spontaneous occurrence of hyperpolarizing potentials(More)
The all-rod retina of the skate (Raja erinacea or R. oscellata) is known to have the remarkable capability of responding to incremental flashes superimposed on background intensities that initially block all light-evoked responses and are well above the level at which rods saturate in mixed rod/cone retinas. To examine further the unusual properties of the(More)