Rabbits whose eyes were covered were moved 20-30 cm.in 1-2 seconds on the horizontal plane in the sagital or frontal direction, giving rectilinear accelerated stimuli composed of acceleration and deceleration.The attitude of the head, the trunk and the limbs during the movement were observed.Electromyograms were taken from the deep nape muscles, the deep dorsal muscles, and the extensor and the flexor muscles of the anterior limbs.The same was studied in the rabbits with unilateral or bilateral labyrinthectomy or decerebration.
1.When the normal rabbits were moved in the sagital direction, the electromyographical findi- ngs of the deep nape muscles did not correspond to the posture, the electrical discharge being decreased by foreward acceleration and increased by the backward acceleration.In the accelerated stage of the movement in the frontal direction, the decrease of the discharge was seen in the muscles on the side to which the movement was directed, and the increase of the discharge was seen in the muscles on the other side.
The reaction of the decerebrated rabbits was almost the same to that of the normal rabbits, However, the interval diagrams of discharge of the deep nape muscles were usually more smooth than that of normal rabbits.
2.In the unilaterally labyrinthectomized rabbits, the continuous regular discharge was not demonstrated in the deep nape and dorsal muscles on the healthy side.In the bilaterally labyrinthe ctomized rabbits, the continuous regular discharge was hardly demonstrated in the deep nape and dorsalmuscles on both sides, No respense was observed for the accelerated stimulation.
3.In the bilaterally labyrithectomized rabbits, the response of the anterior limbs was usualy difficult to demonstrate, showing opposite tendency to that of decerebrated rabbits.On the electro- myograms of the anterior limbs, normal rabbits showed two types of response to the rectilinear acceleration seen in bilaterally labyrinthectomized and decerebrated rabbits.
4.The labyrinthine muscular innervation to the deep nape and dorsal muscles seemed mainly to be contralateral.The vestibulo- spinal muscular response was more remarkable in the deep nape muscles and dorsal muscles than in the limbs.

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Otolith and Maculae were removed in the condition as fresh as possible by means of the particular method from frog, guinea-pig and hen.The nature and formation of otolith were studied and the results were as follows:
(1) It was shown by pressure method, X-ray diffraction technique and electron microscope that the otolith was in a gel-like condition in vivo.But when otolithic membrane became to non-physiological condition by the chemical and physical stimuli, the extremely samll crystals got to gather and developed to form the otolith which has been observed as large crystals.
(2) Ca45 was used as a tracer to study the formation of otolith.The rise and fall of Ca45 as tracer were investigated.Ca45 moved rapidly to the otolith and mostly disappeared in 72 hours aftet the injection.It seemed that there were calcium metabolism was present in the otolith.
(3) Carbonic anhydrase was demonstrated in the otolithic organs of hen and frog, especially in high concentration in the otolithic membrane and so called Smith's extramacular portion.
(4) As the results of the administration of various enzyme inhibitors, it was demonstrated that carbonic anhydrase was related to the formation of calcium carbonate in the shell.
(5) From these studies, it seems that carbonic anhydrase plays an important part in the formation of otolith.

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According to Smith et al., the potassium concentration in the endolymph is 30 times higher than that of the perilymph and cerebrospinal fluid.Sodium concentration is only a tenth of that in the perilymph or cerebrospinal fluid.Chlorine in the endolymph is 90% of that in the peri- lymph or cerebrospinal fluid.All three are low in protein.Among those results obtained by them, the unusually high potassium concentration of the endolymph should be mentioned as the most striking evidence.
However the physiological role of this characteristic chemical composition of the endolymph -remained obscure until today.
The contribution done by them suggests a new attempt, that is the experimental observation of symptoms in guinea pigs induced by replacement of endolymph with various fluids, considering also in its relation to the pathological condition of unknown origin of so called Meniere's syndrome.As a preliminary study, the methods of replacement were studied and the responses induced by replacement with artificial endolymph were observed.The results were as follows:
1.The inner ear was exposed by surgical operation and a small hole of 100u in diameter was opend into the membranous canal of the cochlea and of the vestibular canal under a binocular microscope.The apparatus for replacment consists of glass tube measuring 1 mm diameter and 25 cm in length, a rubber tube connected with one end of glass tube, a cock set on the middle of rubber tube and a fine injecting needle on the other end of rubber tube.The artificial endolymph warmed to the body temperature of the animal and injected into the endolymph system with the apparatus through one hole under pressure and the fluid passed through the endolymphatic duct and streamed out from the another hole.Thus the replacement of the endolymph with artificial endolymph was performed.
After the replacement of the endolymph, methylene blue was injected into the endolymph system under the same procedure and the inner ear was dissected under a microscope for the purp- ose of ascertaining the replacement of the endolymph with artificial endolymph.And for the same purpose the histological examination was performed.Thus the method of replacement was eastablished.
2 The pressure of 5 cm H2O was most suitable for the replacement of endolymph.Applying this pressure, the mechanical stimulation to vestibular organ, induced by water pressure, was reduced remarkably and the replacement could be performed thoroughly without any recognizable sign except a few twitch of the eye in the inital stage of the infusion.
3 The replacement of the unilateral endolymph with the artificial endolymph, contains 140 mEq/L potassium, exerted no recognizable effect on the animals.No changes were observed on the eye, posture, movement, EMG-activity of the skeletal muscles, respiration, blood pressure and ECG-activity of the animal.
According to these results, this method was considered as a suitable method in the study of the physiological significance of the endolymph by the replacement of the endolymph with vario- us solutions.

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The effect of the replacement of the unilateral or bilateral endolymph and perilymph of guinea pig with various solutions on the eye, posture, movement, EMG-activity of skeletal mus- cles was studied and its relation of unknown origin of so called Meniere's syndrome was discussed.The results were as follows:

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1.Though histopathological pictures of chronic paranasal sinusitis are complicated and of multiform, the author intended to study and consider them from the condition of connective tissue.
2.A new trial of classification of chronic paranasal sinusitis was made, based on the histo- pathological changes of connective tissue, which ranged from a edematous state in a high degree to marked multiplication of it or fibrous state.
3.According to this classification many of 48 materials were found to belong to I, II, III group and few to IV, V group.Maxillary mucous membrane of chronic sinusitis has a marked tendency to show an edematous change.
4.The distribution of tissue mast cells has a great variation by preparation.Between the types in the classification above mentioned and the distribution of tissue mast cells, close relation, ship was noticed to exist.
5.Tissue mast cells were found oftentimes in the epithelial layer and these cells reached upper half of the epithelium in a large numer of the case.Some of them were found to wanderfrom the free margin of it.
6.In the preparations which exhibited thick basement membranes, mast cells.were observed passing through them with extended processes.
7.Kidney-formed nuclei and constricted gourd-formed nuclei were oftentimes found.Many binucleate cells were also observed.
8.So-called amitosis was observed in these cells.While no mitosis was noticed.

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By using the serial otosalpingographic apparatus, the attitude of the eustachian tube in relation to the deglutition movement was observed.
The materials were 15 patients with the perforation of the drum membrane.Patients were ordered to swallow once during infusing 40% moljodol throuth the perforation.Eight x-ray photographes were taken within 6 sec.in each cases.Twelve cases among them were successfully investigated.
The results were as follows.
1)The movement of the euatachian tube and its surrounding area in deglutition had 3 stadium;primary, maximum, and final.
2)The pharyngeal orifice and the cartilaginous area openedat almost the same time.(The primary stadinm)
3)When the deglutition movement was proceeding, the tubal cartilage moved postero-superio- medially, and pharyngeal cavity became narrow by the constraction of M.levator veli palatini and Mm.constrictores pharyngis.(The maximum stadium)
4)When the deglutition movement almost finished the x-ray findings showed similar condi- tion t the primary stadium.(The final stadium)
5)The X-ray photograph sometimes showed two parts separated by the prominence of M.levator veli palatini.
6)In the case of tubal stenosis the eustachian tube enlarged during swallowing.

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The changes in cochlear microphonics, were studied, after the injection of several kinds of solution into scala tympani of guineapigs, by modified Tasaki's method.Results are as follows:
1)KCl alone is not the solution which reduces cochlear microphonics.MgCl2 reduces mi- crophonics more remarkably.And also high concentration, NaCl and CaCl2 reduce microphonics as well as KCl.
2)E.D.T.A.which removes Ca ion from tissue, is also a strong microphonics reducing agent.but Hyaluronidase which increases permeability of the tissue is not effective on microphonics.even when it is used with other agents.
3)Ace'tylcholin and Adrenalin do not reduce microphonics in ordinary concentration.Ten per cent cocain solution reduces microphonics remarkably.
4)Cationic surface active agent reduces microphcnics most remarkably, and its 0.05%solution produces about 40db loss on microphonics.
5)NaCN(10-1M), CH2JCOOH(5=10-2M)remarkably;NaCN(10-2M), maronic acid(10-2M), moderately;NaCN(10-4M), maronic acid(10-3M), D.N.P.(5=10-4M)slightly reduce the micro- phonics.

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The mode of development of caloric nystagmus was investigated and the following results were obtained:
When the eyes were open in a bright room, the amplitude of caloric nystagmus was remark- ably decreased, but in a few cases using Bartels glasses, the amplitude decreased when the eyes were closed.Even when the eyes were completely covered, the developement of the mystogmus was different in those with closed eyes and those with open eyes, and closed eyes, even when vision was perfectly obstructed, and no definite tendency being different individually.In the dark room, when the position of the eye ball waschanged during the nystagmus the amplitudeand speed of the nystagmus tended to be greater when the eye boll was at the center than when it was turned toward the quick phase-This was different in a bright room and the speed and amplitude of nystagmus also dufferent individuatty.
From these facts, the author assumed that thedegree of development of nystagmus would be inversely proportional to the degree of contraction of the eye muscles which produce motion of slow phase of nystagmus, and that the reduction of the amplitude and speed of nystagmus would be due to automatic crntrol exerted by the visual function over the vestibular function.

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In the open, sound encounters the skull, and occurs penetration, reflection and deflection, which produce pressure in the acoustic meatus resulting in the sensation of hearing.The sound pressure in the acoustic meatus may be related to the direction of the incident sound waves.The author planned to investigate this relation.The sound was generated by a sound source sited at one of 12 possible directions in the horizontal plain;i.e.anterior, posterior, lateral, antero-lateral, latero.lateroanterior, postero.postero-Lateral and latero.lateral-posterior.Hearing tests were performed in a sound proof room by using a speaker, which was connected to an audipmeter and broadcasted frequencies.The intensity of the sound was specially controlled.
The observations were crried out on 30 normal persons, 25 cases of unilaterl deafness and 20 cases of bilateral deafness.
In the case of the normal person hearing improved allways in the sound conducted from the anterior direction and decreased from the posterior direction.In cases with unilateral lateral deafness hearing decreased lateral direction as well as in the posterior direction.In cases with bilateral deafness hearing decreased in the posteior direction as in the normal cases.However, in the cases in which the difference in hearingloss between both ears was great, the hearing pattern is approximstely the same as in patients with unilateral deafess.These phenomena were observed using sound of all frequencies, and it must be emphasized that perpeption of 1500 cps was maximal for sound from the posterior direction.This special phenomenon was confined to 1500cps and was confirned in the all cases.The mean value of the improvement was 4 db.The ixplanation of this special phenomenon is not certain.The author has pointed out that the wave length associated with sound of 1500cps is approximately the lengthe of the sagittal diameter of the skull.
This interesting relation may account for the increased sensitivity to sound of this particular frequency and direction.

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Out of 19 patients who had been taking Kanamycin two suffered from subjective by-effects of deafness, tinnitus and urticaria, respectively, and one vertigo and the rest 14 patients suffered from no by-effect at all.
By the audiogram disturvances were found in 14 patients(73.7%), 57.2% of which were in both sides of the ear.The amounts of dose, by which the deafness was caused, were 5-85g, mostly under 50g, and the deafness began within a period of 3 months.The degree of disturvance was in most cases slight with hearing loss of no more than 30db, and only 3 ears had hearing loss of 35_??_45db.The type of audiogram was mostly the gradual form, but the abrupt and the dip forms were also found.The region of the disturvance gradually increased at 2, 000c.p.s.and most of cases were disturbed in high tones above 6, 000c.p.s.In the use of medicine doses of less than 4g, per week there was no sign of regular tendency, but deafness was found among patients who were suffering from disorder in liver.
The vestibular function showed no change in the Goniometry and the post-rotatory nystagmus test and yet there were some instances of small tendency of increase in the caloric nystagmus, but nothing significant was found in all.

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For the purpose of finding an available method for objective audiometry, an observation was.carried out on the evoked potential of the waking human brain to acoustic stimulus by using the superimposition technique of records introduced by Dawson.
By means of the superimposition technique, the difficulties encountered in detecting the response to acoustic stimuli from the spontaneous activity were found to be mitigated greatly.The results obtained were summarized as follows:
1.The minimal intervals of stimulating tones required to elicit the detectable response were 10 seconds, most efficient intervals being 15 to 20 seconds.
2.Observations on 25 subjects revealed the fact that the ratio of positive response(++ &+).to the stimulation of 1000 cps tone was 80 per cent at the intensity of 30 db above the auditory threshold of each subject.
3.The ratio of positive response to the stimulation of from 500 to 4000 cps tones was foundd to be 24 per cent at 0 db of stimulation, while it rose up to 61 per cent at 10 db, to 65 per cent at 20 db and to 70 per cent at 30 db.
4.The minimal intensity of stimulating tones required to evoke the response did not exceed 20 db above subjective thresholds in 82.6 per cent of the total observations.From these results obtained, conclusion was drawn that the evoked potential in the waking human brain to acoustic stimulation will soon be used as a practical method for objective audiometry.

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One hundred cases of headtrauma were classified into 3 types, on which the vestibular fuction was examined by means of votatory and caloric test.
Subjective disturbances were elicited in 29.0% of these cases, while objective disturbances in 47.%.The latter were hyposensitivities of injured side.
Abnormal findings were revealed by rotatory test in, 75.6%, and 71.4% by carolic test.Most casee of inner ear deafness had the disturbance of the vestibular function, and a para- llelism was found in the between hearing and the vestibular function degree of disturbance.Moreover, positive finding in Romberg test was obtained in 17.0% of the cases.Abnormality in Goniometry test was foind in 11%, in Stepping test in 7.0%, and in walking test in 5.0%.The disturbances of vestibular function was most often elicited by the trauma in the occipi- tal region, and a corelation was noticed in the degree between the disturbavees of vestibular functionn and intracranial lesion.

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Although fenestration operation improves the hearing of the ear with clinical otosclerosis, the improvement is within certain limits because of the lack of the normal mechanism of sound transmission.The expected improvement of the air conduction threshold has been thought to be 20_??_25 db when the bone conduction threshold is within normal limits.The blocking of the tympanic membrane of the fenastrated ear alters its hearing acuity.The author carried out clinical investigation on these changes in hearing and gave a consideration on the mechanism of sound transmission after the fenestration operation.Fifteen ears consisting of 12 ears with complete fixation of stapes and 3 ears with incomplete fixation of stapes were selected for this study, including a case in which the fenestral bony closure was observed six months after the operation and the patient was operated again.
The tympanic membrane of the fenestrated ear is blocked with cotton pellet soaked with 0.2cc of 1% acrinol cod-liver oil, and air-conduction threshold values before and after the blocking were compared.The test was repeated at the intervals of one month, 6 months, and one year after fenestration operation, and the following results were obtained.
1.By the observations made during the fenestration operation and postoperative hearing improvement, it has been verified that otosclerosis occurs among Japanese as well.
2.There are two pathways of the sound transmission after fenestration, namely, by the way of new fenestra, and the other via the round window.The new fenestra is considered to be superior than the round window as far as the transmission of the sound energy to the labyrinth is concerned.
3.In the majority of the cases whose tympanic membrane of the fene3trated ear is blocked with the cotton pellet soaked with 1% acrinol cod-liver oil, hearing is markedly improved in the low and middle ranges of frequency, i.e.at the neighborhood of 250 cps and 500 cps, but hardly any change can be recognized in the high ranges of frequency.
4.In some cases, no changes in hearing in the fenestrated ear are observed after the blocking of the tympanic membrane, The degree of fixation of stapes, and the condition of air conduction thresholds before the blocking of the tympanic membrane seem to be responsible for such condition.Moreover, in the case having bony closure of new fenestra in 6 months after fenestra- tion operation, the hearing decreased by the blocking of the tympanic membrane.
5.The change in hearing by the blocking of the tympanic membrane in the fenestrated ear seems to have no causative relationship with postoperative serous labyrinthitis.
6.The mechanism of the change in the hearing by the blocking of the tympanic membrane in the fenestrated ear seems to be the following:The amplitude of the sound waves entering through the round window are decreased by the blocking of the tympanic membrane, with the concomitant change in the phase, and a considerable difference in the sound pressure between the new fenestra and the round window makes the vibration of the endolymph easier than before the blocking, accelerated by the change of phase.

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The effect of different blocking agents such as dry cotton pellets, 70% alcohol, water, 20% moljodol, 1% acrinol cod-liver oil or mercury was studied on 12 ears on which the fenestration.operation had been done one year ago.The change in hearing was compared before and after the blocking and following results were obtained.
1.Regardless to the blocking materials used, the change of hearing after the blocking is.remarkable betwen 125cps and 1, 000cps, but the hearing does not change at 2, 000cps, 4, 000cps, or 8, 000cps.
2.The effect of blocking with dry cotton pellet, instillation of alcohol or water is minimal- Instillation of moljodol, acrinol cod-liver oil or mercury shows almost equal effect.
3.There is a limit in the improvement of hearing by the blocking of the tympanic membrane, being less than 15db, and the maximum value of the air-conduction thresholds after blocking was- 10db loss.
4.The difference in the effect of various blocking agents on hearing is not necessarily depen dent on the specific gravity of the agents.From present studies it may be said that oily subs- tances seem to bring better effects on the hearing improvement compared with other agents.

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17-ketosteroid contents in urine were estimated by meams of DIREKTER's method modified by KISHIMOTO and MATSUMOTO, on the patients of various diseases such as chronic paranasal sinusitis, chronic suppurative otitis media, chronic tonsillitis, atrophic rhinitis and carcinomas of the maxillary sinus, pharynx, larynx and esophagus, as well as sarcoma of the tonsils.Particularly, in the patients with chronic sinusitis, a comparision of different values of 17-ketosteroid contents in the urine were made in association with age, sex, duration of illness, presence of hepatic dysfunction, histopatholcgical changes of the mucous membrane and the influence of operative intervention.
On the other hand, the mixture of 17-ketosteroid in urine were analysed by paper chromatography.The following results were obtained:
The difference between the 17-ketosteroid contents in the urine of cases without carcinomatous ca:hexy or hepatic dysfunction and those of normal were found to be slight.
The 17-ketosteroid contents in the urine of patients with chronic siunsitis or chronic suppurative otitis media showed a tendency to decrease, while in cases of chronic tonsillitis, they remained approximately within normal values, in case of atrophic rhinitis being markedly decreased.
In cases of malignant tumors, however, they were revealed to show inconstancy, depending upon each individual, which might exhibit either an increase or decrease.The 17-ketosteroid contents in the urine of patients with chronic paranasal sinusitis showed variations dependable on age, sex and the grades of inflammation of the mucous membrane.
An operative intervention was also found to cause a shift in the 17-ketosteroid contents in urine and it had been already pointed out by ALBRIGHT.
The fluctuation of value of the 17-ketosteroid was influenced by the degree of operative inter- vention;for example, in cases with a restricted diet after operation, there was a marked tendency to show variations in its value.
On the other hand, 36 patients with chronic paranasal sinusitis were investigated by paper chromatography, androsterone being recognized in all cases, etiocholanedione in 9, progesterone in 2, pregnandiol in one and unknown steroids with indefinite Rf-value in 4.
The fate of androsterone was different from that of 17-ketosteroids.
In this connection, the authors possess prospective view that if we could improve the techniques of paper chromatography, we should be able to obtain more interesting findings.

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In 1934, Quelprud named this prominence crus cymbae.Though there are some other names for it, the present author proposes to designate it"eminentia conchae anterior".Because the most part of the prominence is an independent cartilagious protrusion, "Crus"seems an inadequ- ate name.

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As the result of the present author's observation made on 5, 110 Japanese(male, 2, 802;female, 2, 308), the following conclusions were obtained.
1) The occurrence was 15.71±0.50%.
2) The occurrence was higher in female.
3) The unilateral occurrence was 42%.
4) The occurrence tended to decrease with age.No parallelism was found between the occurrence and the development of the other parts of the concha and it was inferred that the central part of the concha was destended with the development of the conchae.

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Classification and measurement of the prominence were made.The features noted were as follows:
1) The highest prominence was 3.5mm in hight.
2) As to the height the prominence was classified into four groups.Asymmetry was frequent and observed in 46.7%.
3) The majority belonged to the normal type in shape.The special types were rare.

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The following results were obtained after examination of the pedigrees 81 families with the prominence.
Though this trait is inherited dominantly, its manifestation is irregular and the expressivity varies greatly.
The author in addition investigated the concha of monkeys of various species.In apes the prominence, which is observed in man.was hardly noticed.

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The author reported 2 cases of inner ear deafness with reversible change, together with their audiograms.
The first case was Streptomycin allergy with generalized exanthema.It was thought that the deafness was due to locol symptoms of allergy in the inner ear, such as edema.
The second case had episods of sudden, reversible deafness and tinitus for several years.
The deafness was perceptic in nature with reduced bone conduction.The cause of deafness was considered to be hypofunction inproper function of the inner ear windows.
The author also pointed out that as a rule, the bone conduction was reduced when the inproper unction of the both inner ear windows was present.

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The author made a study of functional compensation of hearing acuity after removal of the bilateral auditory cortices in cats, using avoidance conditioning procedure, and explained its mechanism from the electrophysiological point of view.
The results are summarized as follow:
1) The auditory threshold was fixed at 10 to 20 db above normal hearing threshold one month after removal of bilateral auditory cortices.
2) At the time above mentioned, evoked potentials, which were not recognized preoperatively, appeared with auditory stimulation to be recorded from the ventral part of the posterior sigmoid gyrus.The latency of this evoked potential was 10 to 11 msec.
3) The auditory threshold did not recover better than 45-65 db loss when bilateral sigmoid gyri with auditory cortices were removed.
4) Unitary activities, which were recorded extracellularly with superfine micro-electrodes were found to be"on effect"responses(by Katsuki), being resemble to the type off response of the primary auditory area.However it has more spontaneous discharges and more frequent abolition of response than that of the primary cortical auditory area.
5) Abolition of spikes responded to sound stimuli was similarly recognized in intracellular reocrding but excitatory postsynaptic potentials responded constantly to sound stimuli, and indica- ted the arrival of presynaptic volleys to this unit.This phenomenon is considered as the response pattern at the intermediate stage on the way to the completion of con pensatory function.
Monakow laid an emphasis on, the release from diaschisis as a mechanism of functional reco- very after brain damage, .and denied the compensation in narrow sense because of the lack of its corroborative evidence.
The above mentioned results proved the compensation of auditory function to be exist in narrow sense.

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Total serum protein contents and electrophoretic fractions in patients with chronic sinusitis were estimated, and the values were compared with that in healthy persons on the point of view on mucosal type, autonomic nerve function and operative intervention in the former cases.Further, experiments were mode on rabbit sinusitis and the following results were obtained.
1) Total serum protein contents in patients with chronic sinusitis showed a slight increase, when they were compared with that in healthy persons.But a decrease in albumin and an increase in globulin fractions, especially of r-globulin was noted electrophoretically.
2) Total serum protein contents and their fractions in the various mucosa from showed only a small difference.
3) Total serum protein contents in vagotony and their labile states showed a slight increase, when they were compared with that in normal persons.A decrease in albumin and an increase in globulin fractions was noted electrophoretically.
4) Postoperative total serum protein contents showed an increase, when they were compared with the preoperative contents and a decrease in albumin and an increase in globulin fractions.was noted too.
5) Fluctuations of serum protein in patients with chronic sinusitis were influenced mainly by grade of destruction of local protein and by function of various organs e.g.liver, kidney, .glandula suprarenalis.But from experiments on rabbits, we found that the cause of fluctuations in serum protein was influenced by degree of stress, whether it was inflammatory or allergic.

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Recently, the Difference Limen Test(D.L.T.) has been used as a routine method for hearing test, but standard values have not yet been established.The authors have tried to determine the range of normal values for this test.The observations were carried out using three standard audiometers with sine wave(3c/s).The Difference Limen(D.L.) and Difference Limen Difference (D.L.D.) in persons with normal hearing have been estimated using 10, 20 and 40db intensity of each frequency.Mean values calculated at next freauencv are as follows:
Then D.L, and D.L.D.were determined in patients with known deafness at two intensities which were 10, 20 or 40db above the threshold of hearing, in each frequency.These results were compared with the normal values.If the results in patients with deafness are smaller than the standards, the test is considered positive and if they are larger it is considered as being negative.A positive value for this test suggests that recruitment phenomenon in the deafened ear is present.

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