Loudness Recruitment Research Articles

A consideration on reduced amplitude in Bekesy audiograms

Bekesy audiograms were compared between tracings with continous and interrupted tonal stimulations. In accordance with Jerger, reduced amplitude in Bekesy tracings in cases with cochlear lesion were observed exclusively when the test was administered with continous tone, but this change was not recognized in the test with interrupted tone. On the basis of this fact, the authors came to the conclusion that the amplitude reduction in Bekesy audiograms observed in the ears with perceptive deafness must be considered as a representation of abnormal adaptation, not of loudness recruitment.

Studies with artificial neurons. II. Analog of the external spiral innervation of the cochlea.

1. Artificial neurons (neuromimes) are used to simulate the external spiral innervation of the cochlea. 2. On the basis of the experimental observations the proposition is advanced that the spiral innervation serves to extend the dynamic range of the ear. Dynamic range extension follows from elementary considerations of the refractory and summing properties of nerve fibers. 3. Experiments with different neuromime densities, supported with psychophysical observations reported in the literature, lead to the hypothesis that dynamic range and growth of sensation are related to the innervation density in the area of sensory tissue under consideration (e.g., skin). The spiral nerves are considered as a special case of a more general sensory nerve, branching in binary fashion. 4. The pathological phenomenon of “loudness recruitment” is explained as a “thinning” of cochlear innervation density, giving rise to smaller dynamic range and faster growth of loudness.

Die Tonhöhenunterschiedsschwelle und ihre Beziehungen zur Intensitätsunterschiedsschwelle in klinischer Hinsicht

After a brief review of the effects of some important factors on the differential sensitivity to frequency the author compares the difference limens for frequency obtained in different cases of „cochleo-neural” deafness with the difference limens for intensity and the speech audiograms. By means of the reported examples it is shown that there is no correlation between the pitch-discriminative function and the phenomenon of loudness recruitment. Moreover, on the basis of the results of some recent electrophysiological and cytoarchitectonic investigations, the behaviour of the differential threshold for frequency in cases of central dysfunctions is briefly discussed.

Differential Pitch Threshold Shift Associated with Moderately High-Level Background Noise

Normal ears are known to exhibit a distortion of the normal loudness growth function (pseudo-recruitment) in the presence of threshold shifting levels of thermal noise. A deterioration of the pitch discrimination function has often been associated with loudness recruitment in abnormal ears. This study involves the determination of differential pitch thresholds (DPT) for normals in the presence of 50- to 70-db threshold shifting levels of thermal noise for comparison with determinations in quiet. Testing for DPT was done with an automated instrument using a modified method of constant stimuli. Frequencies tested were 500, 1000, 2000, and 4000 cps at 50-db SL. Levels in the noise situation were equated to the quiet SL using a loudness balancing method. Maximum shifts in the DPT were found at the highest frequency though most subjects showed noticeable shifts at the other frequencies, also. As might be expected, some increase in variability is also evident in the data obtained in noise. (This work supported in part by a Public Health Service grant.)

Destructive therapy for Meniere's disease.

It is not my intention here to discuss in full detail the various pertinent questions relating to this important problem or to describe completely the techniques by which the labyrinth can be destroyed. However, on the basis of personal experiences, I will endeavor to set down some of the pertinent facts regarding destructive therapy. A sudden attack of severe vertigo accompanied by nausea and vomiting is a terrifying experience. When the episodes in Meniere's disease recur frequently, patients are fearful of having attacks while at work or on the street. At this stage, they are incapacitated and willing to make some sacrifice to acquire relief of symptoms. Before destructive therapy can be advised, it is essential that the following criteria for conclusive diagnosis be met: (1) attacks of vertigo and vomiting; (2) perceptive type hearing loss manifested by threshold loss for bone and air conduction (Fig. 1); (3) loudness recruitment in the involved ear, and (4) diminution of caloric response in the in volved ear.

An evaluation of perceptive hearing losses in children, based on recruitment determinations.

127 children from schools for the hard of hearing suffering from perceptive hearing losses were investigated with view to the phenomenon of recruitment of loudness. Hearing disorders caused by conditions existing pre-natally most often exhibit the presence of recruitment and are presumably of cochlear origin, while those due to postnatal diseases are characterized by the absence of recruitment and appear to be of retrocochlear genesis. In patients with a history of paranatal disease either cochlear or retrocochlear damage may be present.Surprisingly many patients did not obtain full benefit from hearing aids and were by no means completely rehabilitated at the time they finished school. This was thought partly to be due to the inadequacies of conventional hearing aids when used in patients with perceptive hearing disorders.

Effect of Loudness Recruitment on Delayed Speech Feedback

No AccessJournal of Speech and Hearing ResearchResearch Article1 Dec 1959Effect of Loudness Recruitment on Delayed Speech Feedback Earl R. Harford, and James F. Jerger Earl R. Harford Google Scholar More articles by this author and James F. Jerger Google Scholar More articles by this author https://doi.org/10.1044/jshr.0204.361 SectionsAboutPDF ToolsAdd to favoritesDownload CitationTrack Citations ShareFacebookTwitterLinked In Additional Resources FiguresReferencesRelatedDetailsCited by Hearing Research4:3-4 (251-263)1 Jul 1981Short-term auditory deprivation: Effect on brainstem electrical responseT.Newell Decker and Susan W. Howe International Audiology7:1 (48-54)1 Jan 1968Conductive RecruitmentH Anderson and B Barr Acta Oto-Laryngologica66:1-6 (241-247)1 Jan 1968Delayed Speech Feedback in Normal Hearing and Conductive Hearing Loss, with and without a Functioning Stapedius MuscleH. Ekeland Grönås, Quist-Hanssen and A. Bjelde Acta Oto-Laryngologica62:1-6 (171-184)1 Jan 1966Conductive RecruitmentH. Anderson and B. Barr Annals of Otology, Rhinology & Laryngology73:3 (724-739)1 Sep 1964LXI Perceptual Theories of Middle Ear Muscle FunctionF. Blair Simmons Acta Oto-Laryngologica55:1-6 (81-96)1 Jan 1962Low Level Stimulation in the Differentiation of Middle Ear PathologyAubrey Epstein, Jack Katz and John T. Dickinson Acta Oto-Laryngologica55:1-6 (145-150)1 Jan 1962A Hypothesis Considering Non-Mechanical Aspects of Conductive Hearing LossJack Katz and Aubrey Epstein Volume 2Issue 4December 1959Pages: 361-368 Get Permissions Add to your Mendeley library History Published in issue: Dec 1, 1959 Metrics Topicsasha-topicsasha-article-typesCopyright & PermissionsCopyright © 1959 American Speech-Language-Hearing AssociationPDF downloadLoading ...

Loudness recruitment and vertigo.

Loudness recruitment and vertigo.

On the detection of extremely small changes in sound intensity.

A number of investigators 1-19 have recently reported that certain kinds of hearing loss are apparently accompanied by unusually keen differential sensitivity to intensity. Their studies indicated that, in hearing loss due to cochlear lesion, the patient was able to discriminate smaller intensity changes than a listener with normal hearing. Furthermore, many of these investigators made the assumption that the apparent reduction of the intensity difference limen was due to the presence of loudness recruitment in the affected ear. On the basis of this assumed causal relationship, it was proposed that the measurement of the intensity difference limen afforded an indirect test for the presence of loudness recruitment. A normal-sized difference limen was thought to imply the absence of recruitment, while an abnormally small difference limen was interpreted to indicate the presence of recruitment. Some investigators have failed to confirm these observations. Studies by Liden and Nilsson 20 and Lund-Iversen

Observations upon the neurological mechanism of the loudness recruitment phenomenon.

1. The loudness recruitment angle is defined. It is found to provide a useful quantitative index of the recruitment phenomenon.2. The results are described of a study of the angle based upon 200 cases of unilateral deafness due to Meniere's disease. The magnitude of the angle is found to vary linearly and within close limits, with the amount of the deafness.3. The recruitment angle shows some dependence upon the frequency characteristic of the deafness, being greater with low than with high frequency types of hearing loss.4. The results of a comparative study of two small selected groups of subjects, with and without severe symptoms, suggest that the recruitment angle tends to be increased during the active phases of the disease.5. The results are discussed in the light of recent work on the electromechanical behaviour of the cochlea, and an explanation is suggested of the neurological mechanism of the loudness recruitment phenomenon based upon the dual excitation theory of Hallowell Davis.

Recruitment measured by automatic audiometry.

<h3>Introduction</h3> Because loudness recruitment has assumed significant clinical and diagnostic importance, many tests have been devised to demonstrate its presence. One such test involves automatic audiometry. In 1947, when Békésy¹first described his automatic audiometer, he also suggested that the amplitude of excursions of the audiometric tracing gives a measure of the difference limen (DL) for intensity. It was further reasoned that if recruitment were the result of an abnormally rapid growth of loudness, this rapid growth should be the result of diminished DL's. Therefore, diminished excursions in automatic audiometry have been taken as direct indications of the presence of recruitment. The identity of diminished excursions on the automatic audiogram with DL's and recruitment has been supported by such authors as Reger,⁹Lundborg,⁴and Meurman.⁵On the other hand, Palva,⁶one of the more prolific critics of the measurement of recruitment by automatic audiometry, has

Pitch dependence on intensity in unilateral deafness with recruitment of loudness

Pitch dependence on intensity in unilateral deafness with recruitment of loudness

An auditory loudness recruitment test battery; analysis and comparison of subtests.

The significance of auditory recruitment within the framework of auditory theory today is claiming the attention of a large number of laboratories and clinics. Data relating to the manifestations of the recruiting person are being analyzed. Tests are being devised to indicate the presence or absence of recruitment in the person with impaired hearing. A survey of the literature indicates that recruitment tests can be subdivided into tests of loudness balance, difference limen, and speech sound discrimination. The purpose of the present investigation was to establish, by means of more rigorous statistical analyses than have hitherto been reported, the capability of a series of tests to distinguish between normal hearing persons and those whose auditory perception is characterized by recruitment in the loudness function. The following tests were subjected to such statistical analyses: (1) range of comfortable loudness (RCL) test, (2) difference limen (DL) test, and (3) speech sound discrimination

The cochleopalpebral reflex in normal hearing and hard of hearing persons.

In an earlier report, Galambos, Rosenberg, and Glorig 1 investigated the usefulness of the cochleopalpebral, or eyeblink reflex, as a test of hearing. Normal hearing subjects, in addition to patients with hearing loss, were tested to determine the intensity of sound necessary to elicit an eyeblink response. Clicks were used as the auditory stimuli. The authors indicated that the eyeblink response might serve as a measure of loudness recruitment, since some subjects with relatively severe hearing loss demonstrated a cochleopalpebral reflex at sound intensities of only 20 to 30 db. greater than those required for evoking the eyeblink response from persons with normal hearing. This finding suggests that the cochleopal-pebral reflex can be used as an aid in differentially diagnosing the type of hearing loss. More specifically, conductively deafened patients should require more sound intensity to produce an eyeblink than most patients with a perceptive-type hearing loss

Locus of the lesion in recruiting ears.

The place of loudness recruitment testing in otological diagnosis has been recognized for more than 10 years. However, until recently, the diagnostic value of such tests was limited to the differentiation of conductive and perceptive types of hearing losses. The value of these procedures with respect to the further delineation of the anatomical locus of the lesion in perceptive losses was not realized. With the recent publication of recruitment studies on abnormal ears of various types, the diagnostic value of recruitment testing was increased significantly. De Bruine-Altes 3 was one of the first to include enough varieties of verified causative classifications to make general delineating conclusions; however, there was still a need for data on persons with eighth nerve lesions. Dix, Hallpike, and Hood 7 were among the first to supply such information and to call attention to the value of recruitment testing in differentiating cochlear and noncochlear lesions in

Differential intensity sensitivity in the ear with loudness recruitment.

Differential intensity sensitivity in the ear with loudness recruitment.

New hearing test above threshold and its clinical significance: nature of the recruitment phenomenon.

I. INTRODUCTION TO INDICATE the hearing acuity by audiometer, the lowest pattern of threshold is generally used. No questions regarding this method have so far been raised. Hearing acuity, however, is important for speech on the one hand, and hearing above threshold is practically important on the other. The threshold alone, therefore, does not perfectly indicate practical hearing. In other words, the threshold value indicates the hearing acuity only when the intensity of the presented tone is parallel with the loudness or perceived tone. Fowler (1928), however, found a phenomenon in which the loudness rapidly increases in correspondence to small increases in intensity, and he called this phenomenon recruitment of tonal loudness. From this fact we cannot say in cases in which this phenomenon exists that the threshold pattern indicates actual hearing. Fowler1 (1936) published the balance test of loudness with the binaural loudness comparison and emphasized the possibility of

Recruitment testing in hearing and its implications.

AUDIOLOGY is becoming an icreasingly important diagnostic science and as such may provide important clues to what are now considered to be rather obscure problems. It is our intention to present some of the audiologic techniques now in use for testing for the presence of recruitment in hearing and to evaluate these tests in terms of their validity and availability. At this time, it might be well to review some of what has been written in this area of interest. The literature on recruitment presents a rather confused picture at the present time, but this paper will attempt to describe some of the methods now in use. Recruitment of loudness is a phenomenon involving a foreshortening of the usable range of hearing. A subject with recruitment exhibits an abnormally rapid acceleration of loudness units for a given range of physical intensity units. In other words, though hearing of a recruiting

A brief critical review of loudness recruitment.

A brief critical review of loudness recruitment.

Threshold of reflex contractions of muscles of middle ear and recruitment of loudness.

THE CONTRACTION of the intratympanic muscles brings about a change in the tension of the tympanic membrane and thus in the acoustic resistance or impedance of the ear.¹This change in impedance may be utilized for examination also of the muscular contraction in ears with normal tympanic membranes—as, for instance, in determination of the threshold value. <h3>PRINCIPLE OF MEASUREMENT OF IMPEDANCE</h3> An acoustic impedance bridge²is employed, the principle of which is very simple: measurement of acoustic impedance by comparison. The impedance to be determined—here, that of the ear—is compared (balanced) with a variable acoustic impedance standard. The bridge (Fig. 1) consists of a tube (<i>O, B</i>), the ends of which are closed by the impedances to be compared. The telephone membrane (<i>M</i>) sounds to either side. When the impedance is the same in two planes lying symmetrically in relation to the telephone membrane, a pressure node will arise at