It is generally accepted that the otolith organs are the receptors for linear acceleration. Opinions are divided regarding the actual direction which recieve stimulation and its mechanism in the respective parts of the saccule and utricle.
In order to clear the function of the otolith organs, experimental studies were made of the electromyogram on the reflex and action potentials of the utricular nerve to the linear acceleration, the electromicroscopical fine structure, and the anatomical three-dimensional structure in the cranium.
On the basis of these studies, maculae of the saccule and utricle appear to form 1/4 of the rotatory oval surface from the standpoint of structural function. Both fell linear acceleration in the direction vertical to themselves. Pressure and traction are effective and especially the pressure stimulus predominates the others.
A powerful duplication in function was found between both maculae. It was shown that they are able to feel linear acceleration from every direction, both of them working together.
It is known that eye deviation and nystagmus can be provoked by linear acceleration in the horizontal direction for a healthy human adult.
In our investigation, playing our attention to the usefulness of such reac. tions as unique indicators of the function of the otoliths, we conducted analytical examinations of these reactions shown by 180 patients with vertigo.
An electronystagmography was used in recording the eye movements of the patients, and for linear acceleration the motor driven swing apparatus of our laboratory was employed. The stimulation was given in a simple harmonic motion with the intensity of 3 seconds in period and 50 cm in amplitude.
The reactions indicated by the 180 patients with vertigo showed many differences in comparsion with those by healthy adults:
1) shortness of time in occurrence
2) tendency of direction of nystagmus
3) types and processe of eye deviation
The responses to the stimulation in bitemporal axis are provoked mainly by the saccule, while the responses to the stimulation in body axsis come mostly from the utricle.
from the utricle. The methods used in our experiments are easy in recording the results and in techniques of testing, and we believe that these will be useful as one of testing methods of the function of the otolithorgans in the clinical analysis of vertigo.

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Clinical application of electromyography for human recurrent laryngeal nerve paralysis has brought a lot of knowledge about pathophysiology of the disease. There are many cases with a immobile vocal cord which present voluntary activation of some motor units of the paretic muscles.
The main purpose of the present investigation was to relate electromyographical findings to morphological variations. Unilateral recurrent laryngeal nerve of dogs was dissected. In one group, the nerve was partially removed so that the peripheral stump was not regenerated, whereas the cut ends were sutured in order to facilitate regeneration in the other. In the latter, the distance from the larynx to the dissected point was different among the subgroups. The follow-up studies involved observation of the position and mobility of the vocal cord, electromyography of the laryngeal muscles, measurement of the weight of the muscles, and histological examination of the laryngeal structure.
When the nerve was not regenerated, the weight of muscles was decreased rapidly, becoming about a half of that of the un-affected side in three months. The muscle fibers kept being atrophied and finally they were replaced with connective tissue. Fibrillation potentials had lasted until the muscle fibers almost disappeared. There was no change in the position of the vocal cord while atrophy of the muscles was proceeding except for that, in some cases, the paretic cord looked as if it was slightly lateralized because of atrophy the vocalis muscle.
Regeneration of the nerve took place when the dissected nerve ends were connected. It depended on the length of degeneration when recovery of the muscles was completed. Complete morphological recovery was found even in muscles whose weight had been decreased down to 60% of the normal. The mobility of the vocal cord, however, remained disturbed in the majority of the cases. This could be attributed to misdirection of the regenerated axons.
The weight of muscles which presented dominant fibrillation potentials with a small amount of voluntary action potentials was from 61 to 89% of that of the normal. When voluntary potentials were dominant, the weight of the muscles ranged from 67 to 120% of that of the normal side. In the majority, however, it was less than 100 %. The weight of muscles which gave voluntary action potentials without fibrillation potentials ranged from 71 to 110%. It reached 100% in most cases.

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Ten larynges of hens were studied morphologically under an operation microscope, with a special reference to the evolutional stage of the laryngeal structures. The results of the present investigation were compared with results of previous studies on the same topic by other investigators and by ourselves.
The posterior cricoarytenoid muscle of mammal has been regarded as a derivative of the dilator fibers of the primitive larynx. The results of the present study, however, suggested that it is derived from the posterior laryngeal constrictor in the primitive larynx. In the present study it was also suggested that the arytenoid muscle is originated from muscular tissue which appears adjuscent to the lateral cartilage in a certain stage of evolution, although the arytenoid muscle has been considered a derivative of the posterior laryngeal constrictor of the primitive larynx.
In contrast to mammalian larynges, the glottis is open during phonation in hen's larynx. Most laryngeal muscles in the hen are abductors. The arytenoid muscle only is the adductor. Since the sound generator of the hen is the syrinx, it is presumed that there are neural pathways which functionally connect the larynx and the syrinx very closely.

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Vol. 16 (1970) No. Supplement2 p. 73-122
修正箇所：その他

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