Stationary phase relationships of human scalp EEGs in the frequency range of the alpha rhythm were examined by the method of crossspectral analysis. EEGs were recorded from midsaggital points equally spaced on the scalp in normal and blind adults. Cross-spectral analysis was applied to one-or three-minute records and to successive 10-second records. The generalized component, which usually formed a dominant peak in the EEG spectra, showed a gradual phase advance toward the frontal region but seldom reached 180 degrees, and the phase shift at intermediate points was not linearly related to the distance between them. A parallel relation was confirmed between the increase in the inter-regional phase difference and the decrease in the coherence value. A variety of phase differences was noticed for the more localized subordinate component, and the angles of this component ranged more broadly than with the generalized dominant component. Phase relations of the alpha rhythm in the blind were similar to those of the localized component in normal subjects. Thus, in respect to inter-regional relationships in the antero-posterior direction, the alpha rhythms were classified into at least two types, one closely related to the visual function and the other depending upon some functions other than visual. Effectiveness of the cross-spectral analysis on phase relations of the EEG was discussed in comparison with other methods.

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The effect of hyper-and hypotonic solutions on the electrical as well as the mechanical activities of the bullfrog ventricle were investigated.
Hypertonic solutions up to 400 % tonicity, made by adding sucrose, showed two kinds of inhibitory effect; i. e. a consistent, rapid shortening of the action potential duration and a slowly progressing suppression of contractile tension. The inhibitory effect of the hypertonic solution up to 300 %, made by adding NaCl, was more pronounced on the contractile process than on the electrical phenomena. In this condition, the inhibition of the twitch tension occurred with two time constants. The first, rapid decline seems to be related to the suppressive effect on some superficial site while the slower decreasing phase showed a similar time course as the development of contracture.
Hypotonic (33.3 % and 12.5 %) perfusion revealed triphasic changes in the time course of single twitch without accompanying any parallel change in the action potential.
From these results it was concluded that the bullfrog ventricular muscle has some superficial site for Ca regulation which is very sensitive to osmolarity change.

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The resting potential of various parts of the AV nodal regions of an excised rabbit heart was changed by applying constant electrical current with a suction electrode. The membrane potential was recorded with an intracellular microelectrode and the maximum rate of rise of depolarization was computed. The action potential recorded from the AV nodal cell responded to constant current in a manner qualitatively similar to other myocardiums. The relationship between resting potential and amplitude of action potential was expressed by a straight line, while a sigmoidal relationship was observed between the resting potential and the maximum rate of rise of depolarization. Most of the initial current system in a region was inactivated at the control membrane potential. The maximum value of the maximum rate of rise of depolarization of a region was 30 V/sec which was lower than that of other parts of the nodal region.

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The maximum rate of rise of depolarization of the isolated rabbit S-A node cells was studied with an intracellular microelectrode. Both the amplitude and the maximum rate of rise of depolarization reduced in proportion to the extracellular sodium concentration, but the reduction in the maximum rate of rise of depolarization was greater than that in the amplitude of action potentials.
The frequency of spontaneous activities and the duration of action potentials were increased during application of depolarizing current, while they were both reduced during application of hyperpolarizing current. Both the amplitude of the action potential and the maximum rate of rise of depolarization showed voltage dependent characteristics. The maximum value of the maximum rate of rise of depolarization in pacemaking cells ranged from 2 to 11V/sec and was quantitatively lower than other myocardial fibers. The maximum value of the maximum rate of rise of depolarization in 50% Na⁺ solution was reduced to approximately 1/2 of the control in normal Na⁺ solution.
A sigmoidal relationship was observed between the membrane potential and the maximum rate of rise of depolarization. When the temperature of the perfusate was lowered, the sigmoidal curve shifted toward the negative direction. It is concluded that sodium ion is responsible for the generation of the initial phase of the S-A node action potentials, as in other myocardial cells. However, the amount of ionic current required for spike generation is quantitatively smaller than other myocardial cells.

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Effects of cocaine on a hypogastric nerve-vas deferens preparation of the guinea pig, in vitro, were investigated with the microelectrode and the double sucrose gap methods.
1) Cocaine, at a concentration of more than 3×10^-5 M, depolarized the membrane and enhanced the electrical activity of the postjunctional membrane. These effects were, however, not due to accumulated noradrenaline near the postjunctional membrane.
2) The electrical resistance of the postjunctional membrane was slightly increased by treatment with cocaine (3×10^-5 M) but the length constant of the tissue was almost unaffected. The electrical threshold to evoke a spike from the postjunctional membrane was lowered.
3) Cocaine (3×10^-5 M) did not change the amplitude and frequency of the miniature excitatory junction potentials but it markedly suppressed the amplitude of the excitatory junction potentials evoked by hypogastric nerve stimulation. Cocaine prolonged the falling phase of the excitatory junction potentials.
4) The inhibitory action of cocaine on the junction potential evoked by nerve stimulation was not specific for the adrenergic fiber. Cocaine also suppressed the amplitude of the non-adrenergic inhibitory junction potential evoked in the taenia coli by field stimulation.
5) Exogeneously applied noradrenaline enhanced the electrical and mechanical activities of the postjunctional organ but suppressed the amplitude of the excitatory junction potential. This effect of noradrenaline was still observed on pretreatment with cocaine.
6) In the presence of cocaine, the dose-response curves plotted from the mechanical activity induced by excess [K]_oBor by noradrenaline shifted to the left and the maximum responses evoked by either treatment were enhanced.
7) From the present experiments, it was concluded that supersensitivity induced by cocaine or cocaine potentiation of the mechanical response may be mainly due to direct action on the smooth muscle tissue rather than to inhibition of noradrenaline re-uptake into the nerve terminals.

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The effect of rapid cooling on the mechanical activities of the cardiac muscles of the Japanese toad was examined.
1. The mechanical responses produced by rapid cooling (23-0°C) in both auricular and ventricular muscle preparations were composed of an immediate effect (phasic contraction) and a delayed effect (tonic contraction). The immediate effect was blocked by TTX, but the delayed effect was not affected by TTX and Mn.
2. The tonic contraction of the delayed effect produced by rapid cooling was potentiated in Na-deficient Ringer solution in which an equivalent amount of NaCl was substituted for Tris-Cl. The relationship between the relative tension of the delayed effect produced by rapid cooling and the ratio of [Ca²⁺]/[Na⁺] ² showed an S-shaped curve.
3. Generation of tension development of the delayed effect produced by rapid cooling was obviously dependent upon the extracellular Ca concentrations. There was an S-shaped relationship between the relative tension of the delayed effect and pCa in the extracellular medium.
4. In the test solution containing Ca less than pCa 8.0, no tension development of the delayed effect was observed. However, the rapid cooling contracture was strongly elicited by application of caffeine (caffeine-RCC).
5. The caffeine-RCC was also observed in the presence of 100 mM KCl.
6. From the results of the present study, it was considered that, even though the Ca influx was abolished, the contraction of the cardiac muscle could be produced by another mechanism, probably due to increase of myoplasmic Ca released by rapid cooling from the cell membrane itself and the sarcoplasmic reticulum.

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