Orally administered Banthine appears to have a greater suppressive effect on the human thermal sweating than Prantal, Pamine and Pro-Banthine.

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Using 25 msec single current pulse or repetitive square waves of varying frequencies, the electrical sensitivity of the eye (the reciprocal of the eye's current threshold) was determined under states of a complete dark-adaptation and extrafoveal illuminations of reduced intensities with the least perceptible electrical phosphene as the index. The increase in electrical sensitivity caused by illumination was quantitatively expressed by K, which was defined by the formula K=100 (E-E0)/E0. In this case, E represents electrical sensitivity of the light-adapted eye to the stimulating current with given parameters, and E0, the electrical sensitivity of the dark-adapted eye to the current with the same parameters.
1. The K-value for 25 msec single current pulse exhibited a maximum at a level of 10^-3 to 10^-2 mL, whereas K-values for the repetitive square waves of 20 cps were nearly zero or slightly negative for all the levels of illumination. The findings indicate that the K for 25 msec single shock reflects more sensitively the rod response to suprathreshold light stimuli than K for the current at 20 cps. This justifies our proposed view that pulse width plays a more fundamental role in selective stimulation of the rod elements than frequency of repetition.
2. The K-values were determined for varying durations of the stimulating current consisting of repetitive square pulses. A maximal K was obtained by a current of 25 msec in duration, irrespective of the number of pulses and the pulse width.
3. The K was measured with double shocks with varying intervals. The K took the maximal value when the pulse interval was about 25 msec. In addition, a close similarity in configuration was demonstrated between the scotopic visibility curve of HECHT and WILLIAMS and the spectral distribution curve of K for the twin shocks separated by about a 25 msec interval. Thus, YONEMURA and NANGO'S finding that 25 msec single current pulse can exert a selective stimulating effect upon the rod elements has been reproduced to a certain extent by using twin shocks with about a 25 msec interval.

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1. Old and new facts observed on the L.R. were explained from the author's active area theory.
2. The maximal L.R. denotes the “threshold stimulus for excitation” expressed in fraction of the action potential. Accordingly, the ratio act. pot./ max. L. R. represents the safety factor for excitation in the process of conduction.
3. Classical concepts on the L.R. were criticized.
4. It was stated that the modern active spots theory is essentially identical with the active area theory.
5. The limit of the all-or-none law was discussed.

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Brain regions inducing jaw movement and characters of the induced movement were analyzed on the rabbit.
1. The cortical jaw motor area are strictly circumscribed in the region rostral to area insularis and lateral to area postcentralis. The patterns of the jaw movements from here were single contraction of the jaw at low stimulation frequencies and rhythmic jaw movement of 4.5 to 5.75 c/s at higher frequencies. These jaw movements were predominant in the opening direction. The jaw movements from the. internal capsule and subthalamus were almost similar in characters to those from the cortex.
The jaw movement from the lateral amygdaloid nucleus was also a single contraction of the jaw at low frequencies below 4 c/s and at high frequencies a rhythmic jaw movement of 3.5 to 4.0 c/s was evoked. In this case the movement was predominant in the jaw closing direction and its rhythm was similar to that of natural chewing. As compared with the cortex, the amygdala had a lower threshold and longer latency.
2. The cortical and amygdaloid jaw movements could be elicited independently, and the destruction of one of these areas did not affect the jaw movement elicited from the other.
3. The descending neural pathway from the cortical jaw motor area to the trigeminal motor nucleus is assumed to be via the internal capsule, subthalamus and mesencephalic reticular formation, while the pathway from the amygdaloid nucleus may be via the mesencephalic reticular formation, but not through the internal capsule and subthalamus.

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In this experiment, the physiological function of the neocortical jaw motor area and amygdaloid nucleus in relation to jaw movement were studied in the rabbits.
1. By single unilateral shock to either of the cortical jaw motor areas, internal capsule, subthalamus or deeper part of mesencephalic reticular formation, the digastric muscles showed marked bilateral electromyographic responses. However, the masseter did not respond at all.
2. The corticofugal pathway for jaw movement was found to have an intercalary center in the subthalamic region after passing through the internal capsule. This pathway may have a decussation at the level of mesencephalic reticular formation.
3. Following stimulation of either the lateral amygdaloid nucleus or dorsal part of the mesencephalic reticular formation only the ipsilateral masseter responded electromyographically.
4. The descending pathway from the amygdala is considered to play a predominant part in closing the jaw and that from the cortex is assumed to be the one for opening the jaw.

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The potential oscillations appearing in the olfactory epithelium, nerve and bulb were studied in the toad and the frog.
1. Characteristic potential oscillations were found very frequently in the olfactory epithelium of the toad and the frog. They appeared superimposed on the on-or the off-slow potential at the onset or the cessation of olfactory stimulation.
2. The olfactory nerve and bulb show potential oscillations in response to odour stimulation. They are mutually identical in frequency, phase and shape.
3. The oscillations in the olfactory epithelium are entirely different in frequency, magnitude, shape and time of appearance from those in the olfactory nerve and bulb. It was concluded that there are two kinds of potential oscillations in the lower olfactory nervous system.
4. The potential oscillations in the olfactory bulb of the toad and the frog were compared with those in mammals. The origin of the oscillation was considered.

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1. In a series of intercollicular decerebrated cats, the spinal cord at the level of the second cervical segment was explored with a microelectrode in search for neuronal afferent discharges synchronous with the respiratory movement.
2. Respiratory discharges could be encountered in the cuneate fascicle and in the portion corresponding to the dorsal spinocerebellar tract.
3. Most of the respiratory discharges were found continuous without appreciable silent period, but the frequency of discharge varied in different phases of the cycle. Discharges were classified according to the phase of the cycle during which they occurred. Two types were found, inspiratory and expiratory. Each of them was again divided into three subgroups. Arranged in the order of frequent occurrence, the following types were obtained. A) Inspiratory discharge: i) the slow increment type in which activity builds up slowly and subsides abruptly, ii) the steady type in which constant level of high activity appears suddenly with inspiration, iii) the slow increment-decrement type in which activity builds up and subsides slowly. B) Expiratory discharge: i) the rapid increment type in which activity builds up suddenly and subsides slowly, ii) the steady type in which activity is periodically maintained at a constant high level, iii) the slow incrementdecrement type in which activity slowly builds up and subsides.
4. Numerous units were found whose discharges were elicited only by passive distortion of the thorax. This type of discharges was considered to be of the same origin as the respiratory discharges.

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1. Using single intracellular microelectrodes in a bridge circuit, the effect of electrotonus on the activity of motoneurons was explored in excised spinal cords of toads.
2. A linear relationship was found between the applied current and the changes of the membrane potential, usually within a range of ±2.5 × 10^-9 A, which caused shifts of the membrane potential by ±6 to 8 mV. With stronger currents, the rectifying action of the membrane was usually observed.
3. The overshoot of the spike antidromically evoked remained almost constant, either when the membrane was depolarized or hyperpolarized to a certain extent. Stronger such polarizations, however, brought about insufficient or over-compensation.
4. The effects of electrotonus on the afterpotentials were studied with similar results to those known from other cells.
5. The size of PSP's was reduced by depolarization and augmented within a certain range of hyperpolarization. Monosynaptic EPSP was ineffective in evoking motoneuron spikes in the normal state, but sometimes became effective when the membrane had been suitably depolarized.
6. With the combined application of two long square pulses, the motoneurons were excited directly under various background polarizations. Depolarized motoneurons showed responses only with short latency and a rather constant threshold depolarization. On the contrary, hyperpolarized motoneurons responded even with long latencies, the spike arising from a level of depolarization which becomes markedly higher with an increase in the latent time. The accommodation of motoneurons is discussed in connection with these findings.

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1. The tympanic organ of L. migratoria danica was found to accept well even the ultrasonic waves. The response frequency range was from 0.6 to 45 kcps, the most sensitive frequency range being from 5 to 9 kcps.
2. The mode of conveying the information of the tympanic neuron to the central nervous system was found as follows:
A. The tympanic neuron sent impulses in the pattern of slow adaptation and did not discharge synchronously with the sound frequency as seen on cereal hair sensilla. The relations bdtween the number of spikes per second and the intensity of sound in decibel unit were sigmoid and almost parallel to one another for different sound frequencies A neuron responded with the highest rate of spike discharges to the sound to which the neuron was most sensitive.
B. The largest response area of single tympanic neuron almost covered the threshold curve of the whole tympanic organ and the characteristic frequency of each neuron was almost the same. From those facts it was concluded that in the tympanic organ there was no neuron which had a biased response area and therefore the tympanic organ might not have the ability of analyzing the sound frequency.
3. The slow potentials were recorded from the chordotonal organ. They were divided into four types: negative monophasic, negative-positive diphasic, positive monophasic with an abrupt rise and fall, and also that with a slow rise and fall.
4. The slow potential changed as if it were the envelope of the sound wave and was almost nonadaptive to prolonged sounds. The relation between its amplitude and the intensity of sound in decibel unit was measured.
5. When a prolonged and a short sound were delivered simultaneously, the slow potential evoked by the short sound superimposed on the long lasting one evoked by the prolonged sound. When the response to the prolonged sound was nearly saturated in amplitude, the response to the short sound delivered simultaneously was almost undiscernible.
6. Positive spikes superimposed on the rising phase of the positive slow potential. By weakening of the stimulus sound, a number of spikes decreased with the slow potential, until only the slow potential remained there.
7. It was discussed that the slow potential change obtained from the tympanic organ might be the so-called generator potential of this organ. Such a potential change as the microphonics was not obtained from the tympanic organ unlike the cochlea of higher animals, although the functions of both organs are the same.

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1. Effects of hypothermia on the intracellular potentials were studied on the surviving strips of the ventricular muscle from the mouse, and mode of activities of the fibers was analysed.
2. Lowered muscle temperature caused no appreciable change in the magnitude of both resting potential (RP) and action potential (AP) down to 19°C, but below this temperature, sudden decrease of the potentials were observed. The decrease was more conspicuous in AP than RP, and AP was no longer elicitable at 13°C or below.
3. The ventricular muscle fiber often became spontaneously active at 37°C to 25°C. Double spike was also frequently encountered particularly within the temperatures of 32°C to 22°C, more often in the right ventricle (65%) than in the left one (35%).
4. Both rising phase and repolarization phase of AP were prolonged with the fall of temperature. At temperatures of 19°C and below, AP appeared peculiarly deformed and in about half the number of cases of penetrated cells, inflection came into sight in the rising phase and on some occasions, the spike was fallen off with the slow potential left alone.
5. On the basis of above findings, the possibility is discussed that the intracellular AP of the cardiac muscle is made up of two components, i.e. spike component and slow potential component, and that the latter is a myo-myo-junction potential related to the excitation transmission among the muscle fibers.

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Sensory discharges of cutaneous mechanoreceptors were recorded from single nerve fibre in toads. Three factors which influence the frequency of impulses to constant pressure stimulation were studied, namely, the rate of adaptation, the sensitivity of the receptive field, and the stimulus intensity.
1. The rate of adaptation, based upon the rate of frequency decay and the dura-tion of impulse discharge was classified as rapid and slow respectively. When the initial frequency was almost 50imp/sec., in the rapidly adapting unit, the dis-charge disappeared within 1 sec. and frequency of impulses decayed to one half in less than 0.2 sec. In the slowly adapting unit, the discharge continued for several seconds or 1 min. and frequency decayed to one half in more than 0.2 sec.
2. The receptive field of single nerve fibre was 8 to 225mm.², and the average was 50mm.². Different regions of a receptive field showed different sensitivity to pressure, the centre being more sensitive than the periphery. Single sensitive spots were innervated by at least five sensory units. Th receptive fields overlapped extensively and a single field was innervated by more than ten sensory fibres on the average.
3. In the dorsal skin of the frog segmentally innervated, the innervation field of a nerve trunk spread over the entrances of two other neighbouring nerve trunks on each side, and had a similar sensitivity distribution as that of a single nerve fibres.
4. The stimulus intensity influenced the adaptation rate of the rapidly adapting unit and the impulse frequencies of both the rapidly and the slowly adapting units. The relationship between log10 of the intensity and the frequency of the sensory discharges followed a sigmoid curve, but it was approximately linear in the middle ranges.

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