The single unit analyses have been done in 180 cortical auditory neurons of the cats.A new type of response area was found besides the flat type and the sharp peak type.The neurons of this type had multi-peaks in their response area, sugge-sting the direct projection of afferent fibres from the neurons of the medial geniculate body.Mean latency of the neurons of the flat type was the longest, followed the multipeak type, and the sharp peak type. The neurons obtained from a vertical penetration had the same characteristic frequency, and was presumed to be in a functional vertical column which was determined by the best frequency. Many types of the response area were involved in the neurons of the same penetrations, and an integration mechanism of the frequency was consi derable from the sharp peak type to the flat type through multipeak type.
1) Effects of Dihydrostreptomycin(DHSM) on the cochlea of guinea pig were investigated from the view point of the oxygen consumption which was measured by Warburg's method. sed in Krebs Ringer solution containing DHSM, rate. The cochlea of the DHSM intoxicated animal also showed decrease of the oxygen consumption in the same substrate. However, when amino sugar was added into toxicated specimen. These observations were also seen in the case for the cochlea which was eamaged by sound or degenerated postmortally. 2) Effects of the intermediate metabolyte on the minimum bacteriostatic concentration of DHSM and Kanamycin(KM) were studied. sis bovis were used. minimum bacteriostatic contration of DHSM and the case of DHSM in Escherichia coli. These results support the view that DHSM affect the aerobic metabolism in the cochlea. Role of the acid mucopolysaccharide in the cochlea on DHSM intoxication was discussed.
The auditory acuity of new-born infants was examined by means of an average response computer. Ten subjects were from 3 hours to 8 days of life. Tone bursts of 0.5, 1, 2, and 4KC at 30, 60, and 90 phon.were presented as auditory stimuli. Results were as follows: Above 60 phon.the average responses were obtained from almost all subjects at every frequencies used, but at 4KC it seemed less effective to evoke the responses. Typical response consisted of three positive-negative-positive phases and their latencies were somewhat longer than those of adults. Variations of the response pattern were observed among the subjects.
Monopolar EEGs of eighty-five sleeping infants tnder sound stimulation of 500, 1000, 2000 and 4000 ps.were recorded.The subjects were introducedo our Hearing Speech Clinic for testing their heaing impairment and speech disorders. Despite no auditory response was able to visuaize in the EEGs themselves, clear-cut ones were coated out in some subjects by applying the Simpliied Averaging Method for the average response ime-pattern(Sato et al.1962) to the EEGs, wheeas no response was obtained in other subjects. Hence, it was obvious that auditory system would not be impaired in the former infants, but be donen the latter. The above responses were classified in the following five types: 1.large negative response with or without preceded small positive ones. 2.large negative response with preceded and followed small positive ones. 3.large negative response with longer duration than the above two types. 4.large negative shift with a notch suggesting two responses. 5.very slight or suggested negative response. From the above evidences, it would not be impossible to achieve the audimetry of child by obtaining the average response time pattern to auditory stimulation.
In order to make clear the mechanism of sound conduction of the ossicular chain, the author investigated the alteration of response of the cochlear microphonics through the partial resection of the malleus, the stapes or both of them of many cats at several different points. The results were summarized as follows: (A) After cutting the malleus at either the middle portion of the manubrium or the short process, there appeared little reduction of response of the cochlear microphonics.The losses were about 5_??_15db in the range from 0.25 to 8kcps. (B) After cutting the malleus at both the short process and the manubrium, the losses grew more remarkable at high frequencies, and it was about 40db at 8kcps on the average of 20 ears. (C) The cut through of the tendon of tensor tympani muscle gave only a very slight additional loss of response at high frequencies. (D) After cutting the tendon of stapedius muscle and the malleus at the lateral ligament, there were little changes in the response of the cochlear microphonics. E) After cutting the stapes at either the anterior crus or the posterior, the loss of response was 17 to 18db at 8kcps. (F) After cutting either the malleus at the neck or the stapes at both the anterior crus and the posterior, the loss of response was about 50 to 60db in the range from 0.25 to 8kcps. (G) After cutting the stapes at either the anterior crus or the posterior, the author cut the malleus at the middle portion of the manubrium.There appeared the additional effect of each loss of response. (H) From the above data it is presumed that the contraposition of the navel of the manubrium of the malleus and the short process or the anterior crus and the posterior of the stapes has a special effect for the high tone conduction.
We had a rare case which both maxillary sinuses communicated with each other.The patient, a Japanese housewife, 26 years of age, complained of increased swelling of both cheek region since 4 months prior to first visit to the clinic. Following X-ray examination with the method of Moljodol instillment the operation was performed, and we found that there was a canal in the alveolar process communicated to both maxillary sinuses.The canal was in size of little finger tip, and covered by mucous membrane which continued to those of maxillary sinuses.
Following surgical manipulation of the pharyngeal area, as in tonsillectomy, and especially after local anesthesia of this area, a developement of a shock condition is frequently encountered. A series of studies on the autonomic nervous system in the cervical and facial region have lately been carried out in our department. Guinea pigs were used as experimental animals in the author's investigation.Cocaine was selected for this investigation.Author's experiments were divided into four groups. In the first group of experiments, a certain amount of cocaine was injected into the palate.All of them died from shock.In the next group, a same amount of cocaine was injected subcutaneously.On the contrary none of them died. When a same amount of cocaine was injected intravenously in the third group, only 35% of them died. In the last group, animals were administered with chlorpromazine prior the injection of cocaine into the palate.No death occured in the last group. Histological findings of the lung, the liver, the kidney and the adrenal in the only first group showed the changes described as " Syndrome d'irritation" by Reilly. Shock syndrome resulted from palatine stimulation by cocaine is thought to be Reiley's phenomenon, not due to the excessive absorption of cocaine into the blood flow.