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STUDENTS have long been intrigued by the drumming of the Ruffed Grouse (Bonasa umbellus). Physically, drumming is a wingbeating display performed from a stationary position, usually upon an elevated object known as a "drumming log." The drumming performance has been described in detail by Bump eta]. (1947: 274-276) and Hjorth (1970: 220-225). Functionally, drumming is believed to correspond fully to song, which is lacking in the species (Hjorth 1970: 497), to facilitate spacing of males (Alien 1934, Fow]e 1953: 91), stimulate female sexual development (Hjorth 1970: 497), and to attract females (Alien 1934, Brander 1967). Numerous ideas have been advanced about how the noise is produced (cf. Bump eta]. 1947: 276-278). Recent]y, Hjorth (1970: 225-233) has suggested new explanations of the related questions of how the sound is generated and how the grouse is able to maintain its balance during the drumming performance. The number of wingbeats in and the duration of a drum are variable both within and among individuals (Aubin 1972). The drumming sound is audible to the human ear up to distances of % to • mile (Sumanik 1966: 38) or more. Although grouse have been reported to turn their heads in reaction to neighbors' drums (Hjorth 1970: 489), no reports of how far a grouse can perceive drumming are available in the literature. Use of the radiote]emetric method has enabled the remote determination

Isolated rabbit aortic strips taken from untreated or reserpinized animals and subjected to exogenous adrenergic stimulation in Krebs-Ringer bicarbonate bath, with or without cocaine, can be shown to contract in a biphasic manner much like the smaller ear artery preparations. The two agonists used were metanephrine, which is not readily oxidized in solution, and norepinephrine, introduced either with or without 10 −6 M Cu 2+ . The action of the copper ions in this situation is a simple attenuation of the catecholamine which permits the fast contractile phase to proceed to completion while eliminating the secondary slow phase altogether. From these experiments it is concluded that the aortic contraction resulting from adrenergic stimulation is not really dissimilar to that of the ear artery when one takes into consideration that the different physiologic requirements demand different temporal responses. It is also likely that the apparent lack of interim relaxation between the fast and slow components is due only to the summating effects of the slowly relaxing fast contraction and rising slow contraction. Complete elimination of the interim relaxing phase is virtually assured if EDTA is used as an antioxidant.

In vitro studies using the rabbit ear artery were carried out to examine possible interactions between acetylsalicylic acid, normetanephrine and deoxycorticosterone acetate. Acetylsalicylic acid and normetanephrine alone siginificantly potentiated the response of the rabbit ear artery to noradrenaline by 1.9 ± 0.1 and 2.0 ± 0.2 respectively. Prior treatment of arteries with either normetanephrine or deoxycorticosterone acetate reduced this effect of acetylsalicylic acid; prior treatment of arteries with acetylsalicylic acid reduced the effect of normetanephrine in potentiating noradrenaline. In vivo studies using dogs showed that acetylsalicylic acid potentiated the effects of isoprenaline on cardiac output. It was concluded that acetylsalicylic acid potentiates the effects of catecholamines in vivo and in vitro possibly by inhibiting uptake 2 .

Longitudinal spread of induced activity was analysed in the rat portal vein and rabbit aorta and compared to propagation in the brachial, radial, ear, mesenteric, femoral and posterior tibial arteries of the rabbit. Isometric force in spiral strips or intact preparations was measured during superfusion with Krebs' solution. The lower 20 per cent of the preparation could be selectively exposed to exogenous noradrenaline (NA) or to transmural field stimulation. Propagation was inferred to occur when the amplitude of the local response, relative to that when the entire preparation was stimulated, exceeded the relative length of the locally stimulated tissue. No propagation was found in the rabbit aortic strip. Propagation was less in proximal than in distal muscular arteries. The calculated distance of propagation was greatest in the rat portal vein. The intact limb vessel preparations reponded to NA with phasic contractions. In the ear artery, here was propagation only of the first phase of this biphasic response. These results show that different sections of the rabbit vascular tree display individuality in their ability to support propagation. In general, propagation in the arterial tree appears to be greatest in the smaller vessels.

"The best film music is not heard." Why, then, does even the least musically oriented spectator remark on the musical aura pervading the films of Federico Fellini? Unlike films that accord a pre-eminence to music with respect to the image,' Fellini's works focus only rarely on musical performance as the center of the filmic interest. What lingers in the spectator's mind is the presence of the "background" music in composer Nino Rota's characteristic style: lyrical, festive, contemporary, reminiscent of the fairground. Speaking about the filmic image, Noel Burch makes the distinction between looking-an intellectual activity-and seeing-a nonselective, physiological activity. Similarly, we do not hear the sound track in its entirety unless we selectively listen to it. Further, as the human ear has proven a "lazier" receptor in the cinema than the eye, the spectator's relationship to the sound track is even more complex, and to deal with theoretical and practical problems this poses becomes all the more difficult. Of the sound track's

The fetal development of both the vestibular and cochlear aqueducts will be followed in otological series beginning with tlie 4-month stage. Postnatal progress and mature structure will be traced from the newborn infant to the adult of 70 years (in dissections, serial sections and reconstructions prepared from the latter).These features will be emphasized: histology of the osseous wall and the contained connective tissue; source and course of blood vessels derived from labyrinthine periotic tissue internally and meningeal layers externally; normal range in adult anatomy. On these structural bases, the two channels will be compared, with special reference to their present and prospective role in otological surgery.

Since the first anatomic investigations of the endolymph and of the labyrinthine canals in the human ear by Schellhammer,1Cotugno2and Meckel3in the latter part of the seventeenth and early eighteenth centuries, discussion of the functions of this apparatus has been a favorite theme for physiologists. Although Boerhaave4had theorized on the functions of the semicircular canals, it was Flourens5first, in 1824, by his experimental work, marvellous when we consider the time and the conditions, who laid the foundations for a true knowledge of the connections between equilibrium, head movements and integrity of the canals. This work directed immediate attention to the importance of excitation of the semicircular canals in the study of equilibrium and orientation, and opened a new chapter in physiology. In this paper I wish to make a short preliminary report of some experimental investigations which I have made, regarding the method in which the

In the course of a comprehensive study of the anatomy of the human ear, it was early realized that more precise information was needed on the development and the adult form and structure of the stapes. Not until such information became available could pathologic structure of the stapes be certainly distinguished from normal or the extent of alteration be determined. Of almost equal importance is information concerning the neighboring area—the vestibular window, fissular tracts and islands of osseous tissue of types peculiar to the temporal bone. The present paper represents the initial phase of a study of the stapedial area and includes six developmental stages between the embryo of 22.8 and that of 183 mm. crown-rump length; subsequent papers will carry the study through the stages of infant, child and adult (to the age of 70). MATERIALS AND METHODS For this investigation reconstructions of the stapes, together with the surrounding

Inheritance ofHypertrichosis pinnae auris is investigated in twoBrahman and oneAryakshatriya pedigrees from Andhra Pradesh. The mode of inheritance is compatible with the hypothesis that the character is Y-linked. The age of onset seems to be in late puberty. The improbability of alternative hypotheses is considered. About 6% of an unselected sample of 345 adult males in Andhra Pradesh were found to show such hypertrichosis.

Threshold shifts in the average human ear are dependent upon the physical parameters of the noise to which the ear is exposed. The influence of noise level can be described approximately by an exponential function. High‐frequency noise components cause much greater threshold shifts than low‐frequency components; the point of maximum effectiveness lies near 3000 Hz. In summating the action of different noise components, critical bands of about 1 oct width are effective. Noise components that excite different critical bands produce partial threshold shifts that are, to some extent, independent of one another.

In continuing a comprehensive study of the stapedial region of the human ear, special attention has been given to the stapes, the vestibular window and the associated fissular tracts in developmentally important embryonic and fetal stages. In a preceding article1the steps in morphogenesis were traced as encountered in specimens from 6.7 to 50 mm. in crown-rump length; the current article carries the account through the 150 mm. specimen, at which stage the formation of bone is initiated in the stapes. Both of the contributions just referred to serve to fill hiatuses existing in two more general papers on stapedial, fissular and fenestral anatomy.2 MATERIAL AND METHODS For this stage of the investigation reconstructions of the stapes, together with the surrounding area, were prepared by the wax plate method of Born.3Representative developmental stages were selected for reconstruction at approximately 25 mm. intervals, while comparable or additional anatomic features in

OUR PRESENT understanding of the complex and beautiful structure of the human inner ear is based upon the labors of more than one generation of outstanding 19th-century microscopists, many of them having names that are now firmly attached to one or another type of cochlear cell. Although the great Stockholm histologist Gustaf Retzius 1,2 is no longer closely identified with any specific cochlear structure, it is he who has given us the most detailed graphic representation of the cytoarchitecture of Corti's organ in man. Of the 39 remarkable plates that illustrate the second volume of his incomparable work, Das Gehororgan der Wirbelthiere (1884), the last seven are devoted to his drawings of the human ear, representing a rich variety of dissections of the entire membranous labyrinth and its various parts, cross sections of the cochlear duct, and longitudinal or surface preparations of the organ of Corti of fetus, infant, child

1. Distensibility characteristics of the isolated, perfused rabbit ear artery were measured in the presence and absence of different concentrations of adrenaline. 2. The major effect of varying the adrenaline concentration was to vary the radius at which active tension first developed. This radius was inversely related to the adrenaline concentration. 3. Increases in radius of the constricted artery produced by pressures rising from 40 to 150 mm Hg were small relative to the increase in wall stress. Distension was opposed largely by increases in active tension. With some arteries (60%) an increase in pressure between 30 and 80 mm Hg was associated with a decrease in radius when low concentrations of adrenaline were present. 4. The ability of the constricted ear artery to resist distension at transmural pressures of 100 mm Hg was uninfluenced by the adrenaline concentration provided constriction exceeded 28% of maximal. The static, incremental, circumferential modulus of the artery wall varied little from a value of 6·5 × 106 dyn/cm2. 5. The maximum active tension required to maintain constriction was inversely related to the degree of constriction and hence to the adrenaline concentration. The modulus for fully or near-fully activated muscle was 18·5 × 106 dyn/cm2 of media. 6. Muscle function deteriorated following exposure of constricted arteries to pressures sufficient to overwhelm the constriction. 7. These observations may be explained by a negative feedback system where the contractile elements are arranged in parallel with a length sensor element whose setting is determined by the concentration of adrenaline. The length sensor may be the cell membrane. It is concluded that a radius increase may be a primary stimulus for blood flow auto-regulation.

The author studied on Troger's method for mesurement of the impedance of the human ear drum and checked it in detail experimentally as well as mathematically.The impedance the author obtained by Troger's method is found similar to those of Troger, Geffcken, Waetzmann & Keibs. and Metz, except that of Zwislocki. For example, the impedances are as follows; At 500 cps, 170 ohms by the author, 90 by Troger, 217 by Geffcken, 155 by Waetzmann & Keibs, 120 by Metz, on the other hand 647 by Zwislocki. At 1000 cps. 89 ohms by the author. 125 by Troger, 160 by Geffcken, 73 by Waetzmann & Keibs, 55 by Metz, on the other hand 310 by Zwislocki.The impedance is higher in a lower frequency range and lower in a higher frequency range.Finally the author measured the impedance of a rubber membrane by Troger's method and by another's method which is not avilable to the human ear but most exact only in measurement of acoustical impedance. It could be found from comparison of these two results that the impedance obtained by Troger's method as well as the other's are not correct. A more correct method for the measurement of the impedance of the human ear drum should be developed in future.

The author commences his paper by making some observations on the general arrangements of the ossicula auditûs . The malleus and incus being firmly connected together by ligaments, are considered as a single bone, forming an elastic arch, the anterior extremity of which is firmly attached to the Glasserian fissure, the posterior to the anterior part of the mastoid cells. This arch is kept steady by the actions of the tensor tympani. The movement of this arch is that of rotation; and it is effected by the tensor tympani muscle. When this muscle contracts, the lower part of the arch, consisting of the handle of the malleus and the long process of the incus, is drawn inwards; by this action the membrana tympani is rendered tense, and the stapes being pressed towards the cavity of the labyrinth, the fluid in the latter is compressed.

This paper describes a survey made to determine the range of magnitudes of room noise present in telephone locations. Measurements were made in a total of 250 locations in New York City and environs, distributed among businesses and residences in accordance with telephone traffic distribution. In each location, measurements were made by a marginal audibility method using the human ear as a part of the measuring device, and by a visual indicating meter. A brief description is included of the apparatus employed with each of these methods. Results are presented for measurements made in various classes of rooms, under winter and summer conditions.

ABSENTEEISM among the workers of the Sorocabana Railroad in the department of the electric punch card machines was so high, as compared with that in other departments, that it demanded the attention of a neuropsychiatrist. He presented the following report: "... the patients complain mostly of nervous irritability, lessened capacity for work, palpitation and sleeplessness. They are persons who are maladjusted in their private lives and whose neurotic symptoms show up with nervous fatigue brought about by the continuous noise of the machines. Such employees cannot receive compensation. All the patients but one returned to work after treatment and a varying period of rest." The matter was therefore referred to the department of otology at the Sorocabana Railroad medical service, where it was approached by the study of the room noise and its influence on the workers' ears. This investigation was undertaken from three standpoints: (1) study of the room

A simple function-model of the human ear is used to transfer the sound of the German spoken numbers into channel-time patterns, which are coded and fed into an electronic computer ER 56. For each number a time-normalized characteristic pattern is formed and stored in the computer. For recognition a simple matching program in the computer is used, to compare the time normalized average pattern of all 10 numbers with the individual time normalized pattern to be recognized. Using this method, 95% of more than 1000 numbers — spoken without special care — could be recognized correctly.

1. The effects of dexamphetamine were studied on the responses of rabbit ileum, rabbit ear artery and sheep spleen to sympathetic nerve stimulation after exposure to guanethidine and in the absence of guanethidine. 2. In the absence of guanethidine, dexamphetamine enhanced the responses to sympathetic stimulation and, in the spleen, this was shown to be due to an increase in noradrenaline output. However, the increase in these responses was much less than the increase obtained in preparations treated with guanethidine. 3. Cocaine, in a concentration which produced the same effect on noradrenaline uptake as the concentration of dexamphetamine used, was also effective in reversing the adrenergic neurone blocking actions of guanethidine. 4. It is suggested that the antagonism between dexamphetamine and guanethidine is due to a reduction in the uptake of guanethidine by the nerve endings rather than to interaction of the two drugs at the receptor site for the adrenergic neurone blocking action of guanethidine.

The relationship between bacteria and external otitis in man is vague. Occasionally bacteria are directly and completely responsible for the disorder and antibacterial therapy, as indicated by culture and sensitivity tests, will effect an immediate and satisfactory recovery. Sometimes bacteria play only a secondary role in the production or protraction of external otitis, e.g., although pathogenic organisms are cultured, antibacterial therapy produces only a partial response. Usually, even though microorganisms can be cultured from the external auditory canal, they are found to be completely unrelated to the disease process.

In 1928 Bast1described a fold in the posterior wall of the utricle at the site of the utricular duct which he named the utriculoendolymphatic valve. This name was suggested by its anatomic structure and position. It appeared to guard the opening of the utricular duct into the utricle. This structure was seen first in sections from the ear of a human fetus. In 1929 Wilson and Anson2described the structure in a child, and later that year they also described it in the adult human ear,3having observed it in eleven different specimens. A thorough study with reconstructed models of the utriculo-endolymphatic valve as it occurs in different animals was made in 1931 by Hoffman and Bast,4who concluded that this structure "is a definite and constant feature of the membranous labyrinth of the mammalian ear." Roberts5studied the utriculo-endolymphatic valve in the

Zusammenfassung I. Reaktionen auf Schallreize wurden bisher an 32 Fischarten (aus 14 Familien) zuverlassig nachgewiesen. 2. Spontane Reaktionen auf Tone sind nicht zu erwarten, da die von uns angewendeten Tonsignale fur die Fische keine biologische Bedeutung haben. Zuverlassige Reaktionen erhalt man daher nur nach Dressur auf Tone. Diese Methode ermoglicht auch eine weitgehende Analyse des Horvermogens bei Fischen. 3. Die obere und untere Horgrenze ist bei Fischen mit gut entwickeltem Gehorsinn angenahert dieselbe wie beim Menschen. 4. Die Fahigkeit der Tonunterscheidung ist fur Elritzen (Phoxinus laevis) und Zwergwelse (Amiurus nebulosus) sicher nachgewiesen. Bei einem Intervall von etwa einer Oktave wurden zwei verschieden hohe Tone im Gedachtnis behalten und wiedererkannt. Der beste Fisch lernte sogar die Unterscheidung einer kleinen Terz. Auch mehr als zwei (bis zu funf) Tone konnen gleichzeitig im Gedachtnis behalten werden. 5. Die Horscharfe ist bei den gepruften Cypriniden, Siluriden und Characiniden angenahert dieselbe wie die des menschlichen Ohres. 6. Bei der Elritze (Phoxinus laevis) ist die pars inferior des Labyrinths, also Sacculus und Lagena, der Sitz des Gehorsinnes. Die pars inferior hat keine statische Funktion. Die pars superior (Utriculus und Bogengange) ist der Sitz des Gleichgewichtssinnes; dieser Teil des Labyrinths hat keine Horfunktion. 7. Tiefe Tone (unter 100–150 v.d.) werden, wenn sie sehr intensiv sind, von der Elritze auch durch den Tastsinn der Haut, sehr tiefe Tone (16 v.d.) nur durch den Tastsinn wahrgenommen. 8. Bei den Ostariophysen (Cypriniden, Siluriden, Characiniden und Gymnotiden) steht die Schwimmblase durch die Weberschen Knochelchen mit dem Sacculus in Verbindung. Der Sacculus-Otolith ist zum Auffangen der auf diesem Wege zugeleiteten Schallwellen besonders umgestaltet. Hierdurch erklart sich die abweichende Form der pars inferior bei den Ostariophysen. Diese Einrichtung dient der Steigerung der Horscharfe. 9. Die Nicht-Ostariophysen sind daher im allgemeinen fur Schallreize weniger empfindlich. Dass auch sie durch die pars inferior des Labyrinths horen, ist noch nicht uberzeugend nachgewiesen, aber ausserordentlich wahrscheinlich. 10. Auch bei manchen Nicht-Ostariophysen finden sich Einrichtungen, die der Steigerung der Horscharfe dienen durften. Sie sind aber physiologisch noch nicht untersucht. 11. Das Labyrinth der Fische vermittelt eine Tonwahrnehmung und Tonunterscheidung ohne Basilarmembran. Die Basilarmembran im Ohr der Landwirbeltiere ist wahrscheinlich ein Apparatzur Verfeinerung des Tonunterscheidungsvermogens. 12. Die Fahigkeit der Tonerzeugung durfte bei Fischen sehr weit verbreitet sein. Daher ist auch die biologische Bedeutung ihres Horvermogens nicht so ratselhaft, wie sie fruher erschien. Summary 1. Reactions to sound stimuli have so far been reliably demonstrated in 32 species of fishes (14 families). 2. Spontaneous reactions to musical tones are not to be expected, since the sound signals used by us have no biological significance for fishes. Reliable reactions can therefore only be obtained by conditioning to tones. This method also allows of a thorough analysis of the capacity of hearing in fishes. 3. The upper and lower limit of hearing in fishes that have a well-developed capacity of hearing is approximately the same as in man. 4. The capacity of discrimination of frequencies has been shown certainly to exist in minnows (Phoxinus laevis) and in a cat-fish (Amiurus nebulosus). Two different frequencies about an octave apart could be remembered and recognised. The best fish learned even to discriminate a minor third. And more than two (up to five) tones can be remembered at the same time. 5. In the Cyprinidae, Siluridae and Characinidae tested, the sensitiveness of hearing is approximately the same as that of the human ear. 6. In the minnow (Phoxinus laevis) the pars inferior, that is the sacculus and the lagena, is the seat of the sense of hearing. The pars inferior has no static function. The pars superior (utriculus and semicircular canals) is the seat of the sense of equilibrium; this part of the labyrinth has no auditory function. 7. In the case of the minnow, low frequencies (below 100–150) are perceived also by the touch sensitivity of the skin if they are of high intensity, while very low frequencies (16) are perceived by the touch sense only. 8. In Ostariophysi (Cyprinidae, Siluridae, Characinidae and Gymnotidae) the swim bladder is linked up with the sacculus by the Weberian ossicles. The saccular otolith is specially modified for the reception of the sound waves directed towards it by the above mechanism. That explains the special shape of the pars inferior in the Ostariophysi. These dispositions are responsible for the increase iii sensitiveness of hearing. 9. Fishes other than the Ostariophysi are therefore generally less sensitive to sound stimuli. It has not yet been convincingly proved that these fishes also hear by means of the pars inferior of the labyrinth, but this is very probably the case. 10. In some of the non-Ostariophysi there are, nevertheless, structures which may serve in increasing the sensitiveness of hearing. These have hot vet been investigated physiologically. 11. The labyrinth of fishes has the capacity of the reception of sound and the discrimination of tones, though it has no membrana basilaris. The membrana basilaris in the ear of land vertebrates is probably an organ for the refinement of tone discrimination. 12. The capacity of sound production appears to be very common in fishes. The biological significance of their ability to hear is therefore not so puzzling as it previously appeared.

1. Quantitative estimates have been made of the binding of catecholamines to purified collagen and elastin, and the factors influencing this binding have been investigated. 2. Collagen shows no specificity towards the binding of either the (-)- or (+)-isomer of adrenaline or noradrenaline, at low concentrations. Elastin binds the (-)-isomer of adrenaline and noradrenaline to twice the extent of the (+)-isomer. 3. Tetracyclines inhibit the binding of catecholamines to collagen and elastin. Oxytetracycline 10-4 M produces a maximum inhibition of the binding of (-)-noradrenaline to collagen of 68·4%. 4. The responses of perfused blood vessels to the administration of pulses of catecholamines or to adrenergic nerve stimulation have been measured. 5. Oxytetracycline (10-4 M) potentiates the amplitude of the response of the rabbit ear artery to noradrenaline and to nerve stimulation, ten- and sixfold respectively. 6. Those preparations with a high content of collagen and elastic tissue, the rabbit ear artery and the rat tail, are more susceptible to the potentiating effects of oxytetracycline than one with a low content, the rat anococcygeus. 7. The results of the study suggest that in tissues with a high content of collagen and elastin, binding to extracellular sites is the major mechanism for terminating the response to noradrenaline or to adrenergic nerve stimulation.

Quantitative measurements are reported on the intensities of subjective tones produced within the human ear under single and dual tone excitation. The measurements are made by the exploring tone method. The even and odd subjective harmonics show some differences, indicating that the organ, or set of organs, producing non‐linearity is not the same as the source of asymmetry. The intensities at which these two distorting effects first appear are not the same. The subjective summation tones are, in general, weaker than the corresponding difference tones of the same order. These differences are to be expected if auditory masking is a process occurring within the hearing mechanism.

The functional influence of non-otosclerotic fixating lesions of the middle ear is investigated by reviewing two unusual cases and, experimentally, by creating such lesions in human temporal bones and observing the subsequent alteration in sound transmission. The effect of experimental fixation at each of five specific sites on the ossicular chain is discussed with respect to clinical observations.

(1957). Frequency Modulation and The Human Ear. Acta Oto-Laryngologica: Vol. 47, No. 5, pp. 421-430.

Some experiments concerning the utility of a simple function-model of the human ear for automatic speech recognition are reported. A short description of this function-model which was built by Zwicker, is given. Using a simple recording and evaluation method it is demonstrated, how the channel-time-patterns obtained from the function-model depend on the properties of different speakers. The German numbers “Null, Eins, Zwo, Drei, Vier, Funf, Sechs, Sieb, Acht, Neun”, spoken by 48 speakers are used as speech material.

The human ear shows a fine pitch discrimination combined with a short transient time; the product of bandwidth and transient time is smaller than 1. According to the investigations of G. v. Bekesy the mechanism of this frequency discrimination cannot be located in the inner ear; it must be searched in the cochlear nerve or in the brain.

For the purpose of illustrating the value of graphic records of the heart sounds in the diagnosis of mitral stenosis, four cases in which the only unequivocal evidence of the presence of this valve lesion was furnished by simultaneous tracings of the apical heart sounds and the electrocardiogram are presented. Many patients with early mitral stenosis display low-pitched diastolic murmurs which show no presystolic accentuation and are often difficult to hear. The insensibility of the human ear to sounds of low frequency probably explains why many of these murmurs are missed on auscultation. The advantages which graphic methods possess in their detection are emphasized. In some cases of well advanced mitral stenosis the apical heart sounds heard on auscultation are difficult to interpret, and in these cases also sound tracings are often of great diagnostic value.

THERE HAVE been a number of investigaj tions in the past few years designed to investigate the effects of varying the speed of presentation of meaningful material upon listener compre hension. There have also been studies which have investigated the differences between the auditory, visual, or audiovisual modes of presentation. There have, however, been few studies which have investigated the interrelationships between the speed and the mode of presentation. Goldstein (2) presented connected meaningful material at several rates ranging from 100 to 322 words per minute (wpm) both auditorally and visually. He found an almost linear loss in comprehension as the speed was increased. He also found that for his subjects who ranged in age from 18 to 65 years the auditory presentation resulted in higher levels of comprehension than the visual presenta tion at the lower speeds but that as the speed was increased, comprehension by the visual mode of presentation gradually became equal to that of the auditory presentation. Goldstein varied the rate of presentation by training an expert speaker to deliver the ma terial at the various rates used in the study. This j material was recorded and minor adjustments in speed were made by varying the playback speed of the recordings. Although Goldstein claimed a high level of intelligibility of the auditory ma terial, there is a possibility that some loss of in telligibility resulted from the speaker's increased rate. Goldstein presented the visual material with motion picture equipment. The rate of presenta tion could be very accurately controlled so that it matched exactly the rate of the auditory pres entation. Goldstein's conclusion that there seemed to be no "optimum rate" at which the ma terial should be presented was based upon a rather straightforward interpretation of the linear rela tionship between the rate of presentation and comprehension. If some sort of efficiency index had been calculated, an optimum level might have been determined, but this cannot be computed from the data given. Fairbanks, Guttman, and Miron (4) did compute an efficiency index based upon the number of comprehension test items answered correctly per unit time. Their study, however, was concerned only with the auditory mode of presentation. The optimum rate for the auditory presentation was reported as about 280 wpm. This rate was twice as fast as the original recording and is considerably faster than every day speech. In a later study by Fairbanks, Gutt man and Miron (5) subjects were presented with the material twice instead of just once. The re sults clearly indicate that the double presenta tion at the rate of 282 wpm results in higher comprehension scores than a single presentation at the slower rate of 141 wpm (p

Possible methods of sensory appreciation of the nature of sounds are briefly surveyed in relation to the restriction imposed by the rate at which the nervous system can respond. It is shown that because of this restriction information must in general be lost unless peripheral frequency analysis occurs and unless the peripheral analyzer conforms to certain further conditions which are enumerated. One of these conditions is that the selectivity of the resonant elements shall be proportional to frequency. Experimental evidence is submitted that the selectivity of the resonant elements even in the upper half of the auditory spectrum of the human ear is in fact roughly proportional to frequency and is very much higher than has generally been supposed. Previous theories of hearing are considered, and it is shown that only the resonance hypothesis of Helmholtz interpreted in accordance with the considerations enumerated in the first part of this paper is consistent with observation. In particular the experimental data which have been supposed to be evidence of high damping of the cochlear resonators are re-examined. It is shown that they are either irrelevant or that, correctly interpreted, they are evidence for the contrary view. Finally, an attempt is made to summarize some important properties of the ear in a diagram which illustrates that the ear is a perfect analyzer up to a frequency of 1 kc./sec. Above that frequency it is imperfect, not because of inadequate selectivity, but because perfection would require an impracticable number of resonant elements and nerve cells.

Foreknowledge of the morphological changes on the tympanic cavity and it's sorrounding tissues becomes very important particulars of the preoperative diagnosis on the tympanoplasty.Particularly, preoperative affirmation of many changes on the ossicles, such as the lack of the ossicles, positional and formal abnormalities, calcification, and destructions of the ossicular chain, have many significances on determination of the operative method and prognosisTherefore, many roentgenological studies have been performed by many peoples but those methods are still not available because the ossicles were not observed clearly from it's anatomical reasons.Author reported the result of re-examination the Chausse's method, G. Guillen's method and axial method by using the DAITO-HIRANO's roentgen photographing apparatus.

A computational model is described for estimating basilar membrane displacement in the human ear when the sound pressure at the eardrum is known. The model embodies rational‐function approximations of middle ear transmission and of stapes to‐membrane transmission. The physiological data upon which it is based stem primarily from the researches of Bekesy. Besides computational convenience, the rational‐function format has the additional advantage that the model can, if desired, be realized in terms of lumped‐constant electrical circuits. The model has been found to be a useful analytical tool for relating subjective auditory behavior and the acoustomechanical operation of the ear.

(±)-2-Aminomethyl-1, 4-benzodioxan has been resolved into its optically active isomers: (+)- and (-)-guanoxan have been synthesized from these. The pharmacological effects of racemic-guanoxan and of the two optical isomers have been compared on the isolated central ear artery of the rabbit, on the pithed rat in which pressor responses were evoked by stimulation of the thoraco-lumbar sympathetic outflow, and on the pre- and post-ganglionically stimulated nictitating membrane of the cat. The two isomers were equipotent in producing adrenergic neuron blockade. Initial catecholamine release was weak in the cat, but occurred more powerfully in the rabbit ear artery and in the rat. Ability to produce this effect resided mainly with the (+)-isomer. α-Adrenoreceptor blocking activity was detectable in the rat and was produced mainly by the (+)-isomer suggesting that its stereochemical configuration corresponds to that of D-(-)-noradrenaline. Ganglion blockade was an unimportant action of the compounds, but both isomers possessed weak atropine-like activity in the rat.

A new method for producing pressure variations in the pneumatic system of the human ear under control is described, i.e. the mastoid puncture technique. Several investigations are made; the volume displacement capacity of the normal ear drum, the role of the drum as a middle ear pressure regulator, vacuum effects on hearing and transudation, all these changes arc produced by intra-aural pressure variations under control. The accuracy of the previous methods for indirect determination of the middle tar pressure is analysed.

Albino mice were tested for susceptibility to audiogenic seizures in sound fields of various frequencies and intensities. An attempt to fix the ears of the mice with respect to the sound source by suspending the mice with a large spring clip which grasped the dorsal skin‐fold proved fruitless, for too few seizures were induced at any intensity. The mice were therefore tested in a small wire mesh cage suspended in front of the sound‐transducer, and the positions of their ears during the treatment were recorded. At 10 kc, at least 92 db was needed to induce seizures in mice which had no previous seizures, while only 83 db were needed for animals which had previous seizures. The most effective frequencies for the induction of seizures were between 12 and 25 kc. Below 10 kc, the effectiveness dropped off sharply and was very low at 5 kc. Studies were not made above 25 kc. The peak of the mouse's audiogram is probably near the frequencies which are most effective for induction of seizures and is thus a little lower than that of the rat and about 1.5 octaves above that of man. The ability of mice to hear at frequencies which are ultrasonic for the human ear is probably the reason for the intense reactions of mice to complex sounds which seem of moderate intensity to man.

In conducting researches into the pathological condition of the organ of hearing, I have been impressed with the necessity of ascertaining, with as much precision as possible, the intimate structure of the various tissues entering into its composition. The results to which investigations undertaken with this latter object in view have led me, in reference to the structure of the membrana tympani, it is the purpose of the present paper to detail. It will be observed that the conclusions at which I have arrived, differ materially in various important particulars from those of previous investigators. Examined from the exterior, inwards the membrana tympani consists of the following layers:— 1. The epidermis. 2. The proper fibrous layer, composed of— a . The lamina of radiating fibres. b . The lamina of circular fibres. 3. The mucous membrane (Plate III. fig. 1).

We have presented a new type of recording apparatus which possesses distortion simulating that of the human ear. This permits strict correlation between clinical cardiology and phonocardiographic records. In addition we have established an even base line which permits accurate timing of the beginning and end of heart sounds. The fundamental characteristics of the first and second sounds are described. We suggest that further phonocardiographic studies be performed along these lines. This may be expected to yield more fruitful results than has hitherto been possible. ∗

The fissula ante fenestram has come to be regarded as a constant feature of the human ear and is believed to occur typically as a channel within the bone containing an avascular connective tissue. In early corrosion preparations described by Hyrtl 1 in 1845 and by Siebenmann 2 in 1890 only the medial end of the fissula was demonstrated, and in their figures it appears as a macroscopic projection of the anterior portion of the vestibule. Later, Mayer 3 (1917) and others have described and figured the full structure with its termination on the wall of the tympanic cavity. They have emphasized that it is a fissure-like band of connective tissue within bone, and, because of its location between the cochlear and the canalicular portion of the capsule, they have maintained that it serves as a synchondrosis between them, absorbing the strains incident to growth. From a study

The histology of healthy human skin is fundamentally the same over the entire body. However, in many regions one finds variations from this basic structure as well as variations in the number and type of skin appendages. These regional modifications demonstrate the versatility of the skin in dealing with its environment and in participating in the total body economy.

The propagation of sound, the sensitivity of the human ear, and the distribution of sound in halls are described, and a review is made of experiments in which the reaction of listeners to speech, to concerts in halls, to recorded music, and to sound with artificially added echoes have been measured. The paper concludes with an examination of sound reinforcement systems designed to take advantage of the reactions of listeners.

The opinion usually entertained by physiologists is that two channels are requisite for the transmission of sonorous undulations from the membrana tympani to the labyrinth, viz. the air in the tympanic cavity which transmits the undulations to the membrane of the fenestra rotunda and the cochlea ; and secondly, the chain of ossicles which conduct them to the vestibule. This opinion is, however, far from being universally received ; thus, one writer on the Physiology of Hearing contends that “ the integrity of one fenestra may suffice for the exercise of hearing;” another expresses his conviction that “ the transmission of sound cannot take place through the ossicula;” while Sir John Herschel, in speaking of the ossicles, says “ they are so far from being essential to hearing, that when the tympanum is destroyed and the chain in consequence hangs loose, deafness does not follow."

The well-known Gelle's test for the diagnosis of otosclerosis has been interpreted from a new point of view, and developed the new test method that is more sensitive and simple than previous one.The apparatus consists of audiometer, manometer and Politzer's balloon.The procedure of the test is as follows:The bone conduction sound of 250_??_4000cps, 40db above threshold is imparted to the ear tobe tested, then the pressure of external auditory canal is changed periodically by pressing Politzer's balloon twice a second.The pressure is gradually enhanced and the pressure when the bone conducting tone starts to pulsate is measured by the manometer.The results obtained with various deafness were as follows:1)The pressure was below 5 mmHg with those of normal hearing and perceptive deafness2)The pressure was above 60 mmHg in otosclerosis.3)In the case of other conductive deafness the pressure was.10_??_60 mmHg regardless to the presence of drum perforation.The pulsation of the bone conducting tone in this method has been proved by the experiments on the living human ear to be due to the distortion of the inner ear.This new method which mechanism is fundamentally different from the usual modified Gelle's test, has been designated by the author as″dynamic Gelle's test″.The original Gelle's test must be a kind of this dynamic method.