The intralabyrinthine pressure of the curarized guinea-pig was measured by use of electromanometer of a high sensitivity wire resistance strain gauge type.
By the present experimental procedures, the fine changes of the intralabyrinthine pressure could be thoroughly observed.
Method and experimental procedure;
Guinea-pigs weighning 400-600g were used. The intralabyrinthine pressure changes were recorded by means of a steel pipette mounted on a micromanipulator. The pipette was made from steel tube, its external diameter was about 300μ, and internal diameter of its orifice about 100μ. The pipette was connected with a pressure transducer (strain gauge type, TMI model LPU-0.5) by the aid of the polyethylene tube, the above system were filled with a high-potassium and low-sodium isotonic solution according to C. A. Smith's report.
The animal was anaesthetized intraperitoneally with pentobarbital sodium and was given tubocurarine chloride intravenously. Then, the animal was survived by artificial respiration. The cochlea was exposed through the auditory bulla by a submandibular approach. With the aid of a binocular dissecting microscope, a small hole of about 100μ in diameter was made at the stria vascularis area in the basal turn of the cochlea for the measurement of the endolymphatic pressure. For measuring the pressure of the perilymph, the fenestra was made just below the stria area.
Above procedures were carried out carefully avoiding piercing the soft tissue of the stria vascularis and escape of the intralabyrinthine fluids. Then, the pipette with a drop in its tip was driven with the aid of a micromanipulator to the fenestra, coming in close contact with the fenestra. At this point, the stria was not yet penetrated and all of recording system was still opened to the atmosphere. After the zero point of the pressure was calibrated, again the pipette was advanced in the cochlea.
Immediately after the penetration with the pipette to the cochlear wall, the intralabyrin- thine pressure of 30-70 mmH₂O height was recorded, and then the changes of the pressure could be recorded continuously.
Results;
1) The static pressure of endolymph was about 47 mmH₂O high, and about 50 mmH₂O high in the perilymph (Scala tympani). However, from the histological observation of the cochlea of the guinea-pig, some doubts were raised in measuring method of the endolymphatic pressure.
2) Under normal conditions (not anaesthetized), the intralabyrinthine pressure was not stable, but always changing under the influence of many factors; such as breathing movement, contraction of the tympanic muscles and cerebrospinal pressure changes.
3) Anoxia (asphyxic asphyxia) caused a marked increase in the pressure. The first increase was observed at the beginning of the anoxia, and maintained constant height till the cessation of the anoxia.
The second increase was observed after cessation of the anoxia. In parallel with these increase in the pressure, the pulse wave of the inner ear blood vessels increased its amplitude. This pulse wave was observed as the changes of the intralabyrinthine pressure.
4) Intravenous injection of vasodilator such as papaverine, caused a transient increase in the pressure and the amplitude of the pulse wave.
5) Intravenous injection of adrenaline and nor-adrenaline caused immediate increase in the pressure. Following this increase, a decrease in the pressure continued for several minutes.
6) Intravenous injection of hypertonic solutions such as 20% mannitol, 30% urea, caused gradual decrease in the pressure, and then showed gradual increase. These changes continued for several hours.
7) Occasionally a transient increase in the pressure was measured after intense sound stimulation.
8) Bleeding from carotid artery caused a marked decrease in the pressure.

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It is difficult to study motion sickness, because this disease has no trustworthy signs in the early stage. Nausea and vomiting are most common symptoms, but nausea is not the objective sign and vomiting is not seen in the early stage.
This experiment was planned to find out the sign that was trustworthy and objective in the early stage.
As the stimulation in this experiment, vertical acceleration was used. The apparatus for vertical acceleration is a chair which is hanged by four springs in a steel frame. Vertical swing is given by pushing down the chair with hands. The dimension of acceleration depends on the weight of a subject and amplitude of the swing. When a subject is 50 kg and amplitude is 10 cm, the greatest acceleration becomes 360 cm/sec² and the frequency is 57 per minute. Then the swing continues more than one minute decreasing its amplitude.
The subjects were the students of the nurses training school of Kyushu University. They were divided into two groups. One was the group that often suffers from motion sickness and the other was the group that had done not suffer from it.
The changes of the pulse, respiration, GSR, salvation and galvanic skin resistance caused by the swing of chair were examined.
Experiment 1.
Examinations of autonomic nervous system before the swing.
1. Aschner's eye ball pressure test.
2. spontaneous reaction of GSR.
3. GSR reaction by Essen's method.
4. Abe's breath holding test (BHT).
During the swing that was given five series of greatest amplitude 10 cm each minute.
5. frequency of pulse.
6. frequency of respiration.
7. appearance of GSR.
During the swing, the greatest amplitude was changed at each swing 6 cm, 10 cm and 14 cm.
8. type of pneumotachogram.
9. duration rate of expiration against inspiration.
10. respiratory volume per minute.
After the swing.
11. Aschner's test.
12. Essen's method.
13. Abe's BHT.
The Abe's breath holding test (BHT) is as follows: At first tell a subject to hold his breath as long as he can do (BHT-A). When he will be unable to hold his breath, tell him to draw about ten deep breaths, then ask him to hold his breath again (BHT-B).
Experiment 2.
For thirty minutes, the salivation of a parotid gland and galvanic skin resistance were measured each three minutes before the swing and during the swing. The greatest amplitude of the swing was 10 cm. At measurement of salivation, Krasnogrski's capsule was used. It consists of two chambers. The inner chamber is for gathering saliva and leading it to a small measuring cylinder. The outer chamber is for fixing the capsule on the orifice of Stenon's duct.
Results:
Pulse, respiration, expiratory rate, GSR, skin resistance and salivation showed no significant changes by the swing in both groups. Only respiratory volume indicated a marked increase in subjects with liability to motion sickness (MS subj.) and not in controls.
The tests before the swing, Aschner's test, Abe's BHT, respiratory volume and salivation showed a significant difference between MS subj. and control subjects. The subjects who showed the positive reaction at Aschner's test did not suffer from motion sickness. The controls' BHT-A, BHT-B and BHT (B-A) were significantly longer than MS subj.'s. Controls had much more respiratory volume and less salivation. Thus it seems to be clear that the difference between MS subj. and control subjects bases on autonomic nervous system.
Conclusion.
1) As the index of motion sickness, volume of respiration is valuable to study.
2) The difference of susceptibility between the subjects with liability to motion sickness and control subjects may be based on some factors in autonomic nervous function.
3) Abe's breath holding test is a most useful to examine whether the subjects is liable to suffer from motion sickness or not.

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It is sixteen years since a new method of articulation hearing test was published, and during these years many studies have been made about it, that is, studies on the test words from the quantitative and qualitative points of view, on the relationship between the articulation curve and the kind of hearing impairment, on the relationship between pure tone audiogram and speech audiogram, and other studies.
In 1957, a standardized word list was enacted in Japan which consists of 36 of one figures for measurement of speech reception threshold and 50 monosyllables for speech discrimination test.
Five reports which dealt with the articulation test by means of one hundred monosyllables which included all representative Japanese monosyllables except for phonetically similar ones were investigated. Comparing the discrimination score with each other settled in file (consonants) and rank (vowels) in these five reports,“y” file (ya, yu, yo) showed a remarkably low discrimination score in Tonotsuka's report, all the files except “n” file (na, ni, nu, ne, no) were in fairly good agreement in Fukushima's and Ebihara's results, and “s” and “t” files showed a low discrimination score in Goto's report. Much difference was recognized in “n” and “h” files in all the reports. Remarkable discordance in them about contracted sounds (kya, sha, etc.) was observed, but it was difficult to find its general tendency of mistaking them along a certain line. Concerning the voiceless group,“i” rank showed a remarkably good discrimination score in Fukushima's report. About contracted sounds,“u” rank showed a bad score in Tonotsuka's report while a good score in Goto's.
Different monosyllables have their own tendency of being well or ill heard. When test words are recorded and played back, the personal quality of a speaker's voice, the intensity of each monosyllable and the surrounding noise blur the distinctive peculiarities of the monosyllable and exercise on the discrimination score a powerful influence.
To clarify the personal tendency of hearing a monosyllable, the author performed the following examinations.
The experimental methods:
The subject: ten healthy students, 13 to 22 years old, whose hearing was normal at the air conduction test. Five of them were male and others female.
The pure tone audiometry: to check the changes of pure tone threshold during the discrimination test, the pure tone air conduction audiometry was performed before discrimination test. The difference between the arithmetic mean of hearing loss of the first time for 500, 1000 and 2000 cps and that of the others never exceeded 10 dB.
The speech discrimination test: 100 monosyllables which included all representative Japanese monosyllables except for phonetically similar ones were recorded on a magnetic tape by a male and a female announcer of NHK (Nippon Broadcasting Corporation). Changing the order of monosyllables, 5 tables for each voice were prepared. The interval of pronunciation was decided to be 2 sec. because the subjects were students with normal hearing and the program of the test was very long.
The discrimination test was performed by 10 dB step from 10 dB to 50 dB, and repeated 10 times by male voice and the same times by female voice on each ear.
The examination was performed in the speech audiometric laboratory in the Otorhinolaryngological Clinic of Kyushu University.
The results of the test at 20, 30 and 50 dB for each voice were settled in a confusion matrix. The results at 10 dB and 40 dB of 5 female subjects were settled in 2 confusion matrixes concerning the female voice only.
The results
1. The articulation scores of a certain monosyllable showed a wide variation even when the normal ear was tested by the same voice, using the same equipment. Wider variation was recognized when female voice was used.

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