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Identification of physiologically relevant peptide vaccine targets calls for the direct analysis of the entirety of naturally presented human leukocyte antigen (HLA) ligands, termed the HLA ligandome. In this study, we implemented this direct approach using immunoprecipitation and mass spectrometry to define acute myeloid leukemia (AML)-associated peptide vaccine targets. Mapping the HLA class I ligandomes of 15 AML patients and 35 healthy controls, more than 25 000 different naturally presented HLA ligands were identified. Target prioritization based on AML exclusivity and high presentation frequency in the AML cohort identified a panel of 132 LiTAAs (ligandome-derived tumor-associated antigens), and 341 corresponding HLA ligands (LiTAPs (ligandome-derived tumor-associated peptides)) represented subset independently in >20% of AML patients. Functional characterization of LiTAPs by interferon-γ ELISPOT (Enzyme-Linked ImmunoSpot) and intracellular cytokine staining confirmed AML-specific CD8+ T-cell recognition. Of note, our platform identified HLA ligands representing several established AML-associated antigens (e.g. NPM1, MAGED1, PRTN3, MPO, WT1), but found 80% of them to be also represented in healthy control samples. Mapping of HLA class II ligandomes provided additional CD4+ T-cell epitopes and potentially synergistic embedded HLA ligands, allowing for complementation of a multipeptide vaccine for the immunotherapy of AML. [ABSTRACT FROM AUTHOR]

Introduction: The majority of hearing loss in children can be accounted for by genetic causes. Non-syndromic hearing loss accounts for 80% of genetic hearing loss in children, with mutations in DFNB1/GJB2 being by far the most common cause. Among the second tier genetic causes of hearing loss in children are mutations in the DFNB9/OTOF gene. Methods: In total, 65 recessive non-syndromic hearing loss families were screened by genotyping for association with the DFNB9/OTOF gene. Families with genotypes consistent with linkage or uninformative for linkage to this gene region were further screened for mutations in the 48 known coding exons of otoferlin. Results: Eight OTOF pathological variants were discovered in six families, Of these, Q829X was found in two families. We also noted 23 other coding variant, believed to have no pathology. A previously published missense allele 1515T was found in the heterozygous state in an individual who was observed to be temperature sensitive for the auditory neuropathy phenotype. Conclusions: Mutations in OTOF cause both profound hearing loss and a type of hearing loss where otoacoustic emissions are spared called auditory neuropathy. [ABSTRACT FROM AUTHOR]

The Leu-8/TQ1 antigen, recently shown to be the human equivalent of the murine MEL-14 lymph node homing receptor and now designated as leucocyte-endothelial cell adhesion molecule, LECAM-l, has been used to dissect T, B and natural killer (NK) cells into various subpopulations with different functional properties, such as suppressor-inducer (CE4+ Leu-8/TQ1+) or helper (CD4+ Leu-8/TQ1-) T lymphocytes. Diminished Leu-8/TQ1 antigen density has been reported after lymphocyte activation with B- or T-cell specific stimuli for several days. In the present study, we sought to determine the signal requirements for altered Leu-8/TrQ1 expression. Exposure of freshly isolated peripheral blood lymphocytes to phorbol 12-myristate 13-acetate (PMA) and/or calcium ionophores was found to cause rapid down-regulation of the Leu-8 antigen, with little or no Leu-8 reactivity remaining I hr after simultaneous addition of PMA and calcium ionophores to the culture medium. TQ1 reactivity was changed in parallel with that of Leu-8. Leu-8 expression oft and B cells was sensitive to both PMA and calcium ionophores, whereas Leu-8 expression of NK cells was affected by PMA but not by the calcium ionophore A23187. The effect of PMA on Leu-8/TQ1 expression could be antagonized by pretreatment with the protein kinase C inhibitor, H7, whereas that of A23187 could not. Partial re-expression of the Leu-8 antigen was seen 3 days after addition of PMA alone but not when it was given together with calcium ionophores. After Leu-8 down regulation induced by I hr treatment with PMA or calcium ionophores, Leu-8 re-expression was observed within 24 hr when stimuli were removed by washing. Activation oft cells with anti-CD3 antibody resulted in a partial reduction of Leu-8/TQ1 expression, first detectable after 1-3 hr of stimulation and maximal at 24 hr. Fully mitogenmic concentrations of concanavalin A (Con A) did not affect Leu-8 expression within the first hours of culture. Transient reduction of Leu-8 expression was seen 24 hr after supraoptimal dosages of Con A, but Con A-stimulated lymphocytes cultured for 4-12 days with interleukin-2 (IL-2) retained Leu-8/TQ1 reactivity to a similar degree as fresh cells. In contrast to Leu-8/TQ1, CD45RA expression was not altered after I hr treatment with PMA and/or calcium ionophores but gradually disappeared during I week after Con A stimulation. Thus, Leu-8/ TQ1+ CD45RA+ lymphocytes could be rapidly converted into Leu-8/TQ1 CD45RA+ cells by PMA and/or calcium ionophores in vitro within 1 hr, whereas Leu-8/TQ1+ CD45RA- cells were generated by Con A stimulation over several days. [ABSTRACT FROM AUTHOR]

Cases are presented which show the clinical utility of recording an electrocochleographic response to bone-conducted stimuli. The procedure is fraught with problems of acoustic control and artifact generation, but has distinct although limited values in clarifying masking dilemmas in patients with bilateral hearing loss. [ABSTRACT FROM AUTHOR]

Our experience with an application and technique for electrocochleography, specifically in retardates, is reported. A case is presented in detail; that is, a mongoloid child with many overlapping otological and audiological diagnostic problems. With the combined use of cochleography and tympanometry much of this diagnostic confusion was resolved and management was simplified. This technique is also compared with late evoked cortical audiometry. [ABSTRACT FROM AUTHOR]

Directed migration of lymphocytes from blood into lymph nodes and gut-associated lymphatic tissue, also referred lo as homing, is subject to change following activation. Lymphocyte migration into lymphoid organs in vivo and binding to high endothelial venules in vitro is largely suppressed after short-term stimulation with phorbol esters. The observed functional alterations were correlated with changes in the expression of three putative homing receptors. LECAM-1 (MEL-14 antigen), LPAM-l/2 (α4-integrin) and the murine CD44 (Pgp-1, H-CAM, Hermesantigen equivalent) upon different modes of cellular activation. Expression of LECAM-I (gp90 MEL-14), a lymphocyte adhesion molecule implicated in targeting extravasation into lymph nodes, was found to be lost almost completely within minutes after protein kinase C activation. LECAM-1 re-expression occurred within less than 24 h. Rapid loss of LECAM-1 was also observed after calcium ionophores whereas anti-CD3 or concanavalin A elicited a gradual and heterogeneous loss of LECAM-1 becoming detectable after several hours only. A number of cytokines tested were not able to induce alterations in LECAM-1 expression. In contrast, expression of LPAM-1/2 (α-integrin) and CD44 (Pgp-1. H-CAM), two adhesion molecules supposed to direct extravasation into Peyer's patches, remained stable for hours after every stimulus tested; CD44 expression gradually increased 24 h after mitogenic activation, whereas a small reduction only was observed for the expression of the α4-chain under certain conditions. Thus, reduced extravasation of lymphocytes into Peyer's patches after activation is not due to a decline in the surface density of LPAM-1/2 α-chain or CD44 whereas alterations in migration into lymph nodes parallel the expression of LECAM-1. [ABSTRACT FROM AUTHOR]

Reports on the mucosal vascular addressin MAdCAM-1, a mucosal endothelial adhesion molecule with immunoglobulin- and mucin-like venule (HEV) ligands for the lymphocyte L-selectin homing receptor; Interacting lymphoid cells' display of a `rolling' behavior similar to selectin-dependent rolling of neutrophils observed in inflamed venules.

The deafness mouse has profound sensorineural hearing loss with degeneration of hair cells soon after birth. The mode of inheritance is recessive, and there are no associated phenotypic anomalies. Thus, this mouse provides a model for recessive, nonsyndromic, prelingual deafness. We have mapped the gene causing deafness in the mouse to Chromosome (Chr) 19 by analysis of 230 intersubspecific backcross progeny. No recombinants were found with the microsatellite marker D19Mit14. The loci for two guanine nucleotide-binding proteins are tightly linked to this marker, and they are being investigated as possible candidate genes. The identification of the defective gene in the mouse will help to explain the mechanism that causes hair cell degeneration and is likely to identify a homologous gene for deafness in humans. [ABSTRACT FROM AUTHOR]

Attention is drawn to the association of seborrhoeic dermatitis with certain acute heart disorders. The eruption generally appeared a few days after the onset of the acute cardiac symptoms and chiefly affected the face. The dermatitis lasted two to three weeks. The majority of the patients had no previous history of skin disease. It is suggested that the stress due to the cardiac condition is the main precipitating factor. [ABSTRACT FROM AUTHOR]

The dominance of one ear over the other in the perception of pitch of dichotic chords has been reported by Efron and Yund [J. Acoust. Soc. Am. 59, 889-898 (1976)] and in subsequent studies by that group. The present investigation addressed the existence of correlations between psychophysical and electrophysiological asymmetries. Specifically, the relation between ear dominance measured psychophysically using the Efron paradigm and right-left asymmetries in middle latency auditory evoked potentials was examined in ten normal-hearing adult subjects. Absolute and interwave latencies were obtained for middle latency responses to right and left monaural, binaural, and dichotic presentation conditions using tonal stimuli. Rank order correlation coefficients were used to compare right-left ear and hemifield evoked potential latency differences to measures of ear dominance. Results indicated that latency measures, particularly for components involving wave Pb of the middle latency response, correlated with the direction of ear dominance. The characteristics of these correlations will be discussed. [Supported by NINCDS [sharp/mesh/hash_synonym]NS 11647, the Louisiana Lions Eye Foundation, and the Eye and Ear Foundation.] [ABSTRACT FROM AUTHOR]

Previous studies of dichotic interference of speech by nonspeech challenges have presented targets and challenges at equal intensities In this study targets (CV stops) were first paired monotically with challenges (noise, vowel, sweeps, bleats and CV's) with the target held constant at 70 dB SPL and the challenges varied in intensity. Masking functions of the challenges on the targets were then generated. The dichotic presentations of the challenges vs the targets were then arranged at two levels: (1) that point at which the challenge masked the target to between 62% and 65% and (2) that point at which the challenge masked the target completely (less than chance). Using these monotic masking functions as references we asked subjects to listen only for the targets presented to one ear while the challenges were presented to the other ear. Dichotic interference functions revealed that, despite uniform monotic masking capabilities, the challenges were quite different in their dichotic effects. Bleats and CV's generated the greatest interference dichotically; sweeps generated some interference but, in contrast to bleats and CV's, did not generate a right ear advantage. The implication of these results will be discussed with respect to central organization for speech detection. [Support by NS-11647.] [ABSTRACT FROM AUTHOR]

Patients with circumscribed temporal lobe lesions show large contralateral ear decrements in simultaneous dichotic speech tasks. However, when noise is in the ipsilateral ear, there is little decrement in the contralateral ear scores. As intensity of speech in the ipsilateral ear gradually increases above threshold, scores of the contralateral ear decrease markedly until, with even 30-dB intensity difference in its favor, the contralateral ear still shows a decrement from its monaural level. The nervous system seems to signal its recognition of 'speech' in the ipsilateral ear by suppressing the performance of the contralateral ear. [ABSTRACT FROM AUTHOR]

At the previous meeting of this Society, we reported a lag effect in which the trailing syllable in a dichotic pair was more intelligible with time staggers at 15, 30, 60, and 90 msec. This paper presents data on 12 subjects who listened to time staggers of 90, 180, 250, and 500 msec. A special condition was also added in which the periodic portions of each pair were aligned without concern for the burst onset of the consonant. We called this the 'boundary condition' and included it as a result of our observation that the voiceless consonant when paired with a voiced consonant is generally more intelligible in the dichotic condition. Both ears functioned about the same beyond 180-msec staggers. However, we found the boundary condition enhanced the right ear laterality effect and attenuated the voiceless over voiced preponderance seen in ordinary dichotic simultaneous listening. [Supported by the NIH.] [ABSTRACT FROM AUTHOR]

We had previously reported [J. Acoust. Soc. Amer. 45, 299 (A) (1969)] that in dichotic listening to consonant-vowel (CV) utterances in natural speech, more voiceless consonants were correctly perceived than voiced consonants. In that experiment, the voiceless CVs had a slightly higher fundamental frequency than the voiced; therefore, synthetic CVs with uniform fundamental frequency and duration were used in the present experiment. Twenty normal right-handed females listened to simultaneous (±212 msec) (stop+/a/) synthetic nonsense syllables both monotically and dichotically. In addition to the expected right-ear laterality effect in dichotic listening, we confirmed our previous finding: dichotically, voiceless consonants predominated (73% vs 48%). Monotically, voiced consonants were most often heard correctly (60% vs 47%). An explanation related to onset of change from aperiodic to periodic portions of voiceless vs voiced utterances is presented. [We are grateful to Arthur Abramson and Lee Lisker for the use of theiry synthetic speech material. Supported in part by NINDS.] [ABSTRACT FROM AUTHOR]

While Decker [ASHA 23, 803 (1981)] reported no relationship of handedness to auditory tract preference in the auditory brainstem response, we know of no data for the middle and late potentials. This study examines the relationship of binaural interaction and lateral asymmetry in the middle and late potentials to handedness. Binaural, right monaural, and left monaural 100-μs pulses were presented to six right-handed and six left-handed normal-hearing subjects in four conditions of earphone and electronics rotations. Middle and late potential data were analyzed statistically using a time series ANOVA. Lateral asymmetries and binaural interaction were derived by subtracting left from right responses and summed monaural from binaural responses, respectively. Data indicate individual differences in the amount and direction of asymmetry. The characteristics of binaural interaction and lateral asymmetry, the relationship to handedness, and the influence of stimulus and recording asymmetries will be described for the middle latency and late potentials. [Supported by NINCDS [sharp/mesh/hash_synonym]NS11647, the Louisiana Lions Eye Foundation and the Eye and Ear Foundation.] [ABSTRACT FROM AUTHOR]

Substantial variability has been reported in the binaural interaction of middle latency potentials [Dobie and Norton, Electroenceph. Clin. Neurophysiol. 49, 303-313 (1980)]. The present investigation studies intrasubject reliability and intersubject variability of binaural interaction and lateral asymmetry in the middle latency response by employing a factorial design addressing potential earphone and electronic channel asymmetries. Summed monaural responses were subtracted from summed binaural responses to yield the binaural interaction component (BIC), while lateral asymmetries were derived by comparing right and left responses under both monaural and binaural conditions. A point-by-point analysis of variance was carried out on the middle latency responses and an exact determination was made of the probability of specific similarities. Data obtained from four subjects, each tested under 48 conditions, describe the reliability of binaural interaction and lateral asymmetry in the middle latency response, the effects of earphone and channel differences on these measurements, and consistencies within and across subjects. [Supported by NINCDS NS 11647, the Louisiana Lions Eye Foundation, and the Eye and Ear Foundation.] [ABSTRACT FROM AUTHOR]

At the previous meeting of the society we presented data on binaural asymmetries in the auditory brainstem response. Individual data show that the binaural interaction was difficult to replicate and resisted systematic reliability studies. In the present studies a factorial design was used to reduce contribution of earphone and electronic channel assymmetries. Although binaural interaction (defined as the sum of binaurals minus the sum of monaurals [Σ BIN-(Σ MON R + L)]) was seen in group data it was not reliably obtained from all subjects under all conditions, confirming R. Dobie [J. Acoust. Soc. Am. 71, 1031-1033 (1982)]. However, differences between responses acquired from the right and left sides of the head were quite systematic, and reliably duplicable from subject to subject and from condition to condition. A statistical program to perform point-by-point analysis of each of the auditory brainstem responses was written and designed by one of us (LFH) and allows an exact probability determination that specific similarities occur by change. [Supported by NINCDS [sharp/mesh/hash_synonym]NS 11647.] [ABSTRACT FROM AUTHOR]

Twenty normal listeners generated auditory brainstem responses to simultaneous condensation 100 μs transients of 70 dB HLN to the left ear, right ear, and finally under binaural conditions. ABR was recorded simultaneously through two matched preamplifiers with vertex as a G1 electrode, the respective ear lobes as G2 for each preamplifier, and the nasion as a ground. Because of the recording montage and because, during binaural stimulation both right and left preamplifiers were active, it was possible to study asymmetries in the following five relationships: (1)[BinR - BinL], (2) [BinR + BinL] -ε[RI + RC) or (LI + LC), (3) [BinR + BinL] -ε[RI + LC) or (LI + RC)], (4) [BinR + BinL]/2 -ε[LI + LC) or ε(LI + LC) or ε(RI + RC)], (5) [BinR + BinL]/2 -ε[(LI + RC) or ε(RI + LC)], in which R = biological data from right amplifier, L = biological data from left preamplifier, I = ipsilateral stimulation, C = contralateral stimulation and Bin = binaural stimulation. Data support, Decker and Howe [J. Acoust. Soc. Am. 69, 1084 (1981)] in that either the left or right ear usually dominates the binaural interaction, but also show that recording montage and binaural stimulation conditions lead to other forms of recordable asymmetries. [Work supported by NINCDS 11647.] [ABSTRACT FROM AUTHOR]

Ten normal listening subjects heard 100 μs electrical pulses transduced by a TDH-49 headphone, presented monaurally and then binaurally at 60 dB HLn. Auditory brain stem responses were recorded from the scalp in 12 referential and differential configurations: M1, M2, T3, T4, C3, C4, (C2 - M1), (C2 - M2), (T3 - M1), (T4 - M2), (C3 - M1), and (C4 - M2). We found a binaural interaction asymmetry not ascribable to any individual monaural asymmetries nor to any acoustic or vibro-tactile 'cross-talk' between the sides. This binaural interaction asymmetry reverses in polarity between mastoid and temporal sites and can be recorded at approximately 6-ms latency from all the recording sites used. [Work supported by scholarships from Ohio University, MRC Grant 9634/19, The Burroughs Wellcome Fund and NINCDS No. NS-11647.] [ABSTRACT FROM AUTHOR]

Children aged 7, 9, 11, 13, and 15 years were tested on their ability to identify simultaneous and time-staggered dichotic consonant-vowel (CV) stimuli. At each age level, 15 males and 15 females listened to 300 dichotic trials, 60 trials at each of five onset asynchronies: 0, 15, 30, 60, and 90 msec. Simultaneous-onset results confirmed earlier dichotic findings in children: age-related performance increases and superior right-ear performance. In addition, the data revealed a lag effect with temporally asynchronous stimuli in a pattern similar to adults. However, the lag effect in younger children was more pronounced at 90 msec than at the 30 msec usually seen for adults. [Supported by NIH.] [ABSTRACT FROM AUTHOR]

The effect of unilateral intensity variation on the interaction of dichotically presented stop-vowels has been shown to result in a reciprocal performance trade between the ear receiving the attenuated signal and the unaffected ear [Brady-Wood and Shankweiler, Haskins Labs Stat. Rpt. 34, 119-126 (1973); Cullen et al., Brain Lang. 1, 307-322 (1974)]. These studies, however, employed only like vowel pairings. The study reported here employed the vowels [æ, i, u] plus the stops [b, d, g] to investigate intensity trade with differing vowels and stop formant transitions. Trading was observed for all pairings, although distorted in some cases by performance ceiling and floor effects. Other results suggest factors in addition to acoustic overlap enter into performance limits and trading relationships observed in dichotic speech studies. [Work supported in part by NH 11647-01 and NIGMS SF I-F03-GM-52343.] [ABSTRACT FROM AUTHOR]

In normals, time-staggering a pair of dichotically presented CVs leads to a 'lag effect.' After anterior temporal lobectomy, the lag effect disappears, but the lesion-ipsilateral ear still shows the effects of some residual competition by virtue of its continuing to perform at less than 100% intelligibility. By contrast, after total hemispherectomy, the lesion ipsilateral ear tends to perform at or near 100%, implying that no residual competition, either phonetic or acoustic, exists between channels at the central analyzer. The impact of this observation on the nature of the dichotic listening task and the lag effect will be discussed. [ABSTRACT FROM AUTHOR]

Ten subjects participated in eight weekly dichotic testing sessions. During each session subjects received 120 random dichotic pairs of the CV syllables [ba, da, ga, pa, ta, ka]. Subjects were asked to identify both syllables, indicating which syllable was clearer. The magnitude of the right-ear advantage (REA), which is typically found under such listening conditions, was measured in several ways and found to vary only slightly over sessions; overall accuracy of identification for both ears, however, was found to increase to an asymptote after about five sessions (600 trials). The observed stability of the REA suggests it to be a reliable measure with as few as 120-240 trials. Also discussed are (1) the implications that these results have for models explaining the REA and (2) some interesting individual variations from the group results. [Work supported in part by NIH grant funds.] [ABSTRACT FROM AUTHOR]

A total of 150 right-handed children (15 boys and 15 girls in each age group: 5, 7, 9, 11, and 13) listened dichotically to 60 pairs of precisely aligned nonsense syllables. All children had normal peripheral pure-tone sensitivity and monotic syllable intelligibility. A right ear advantage was seen even in children 5 years of age with no differences between the sexes as a function of age. The size of the right ear advantage and the nature of the phonetic errors, as well as the interactions between ear, age, sex, and phonemes will be presented. All effects will be discussed in terms of double corrects (where both items of the pair were correctly perceived) and single corrects (where only one item of the pair was correctly perceived). [ABSTRACT FROM AUTHOR]

Three studies are reported in which the intensities of dichotic stimuli were varied. In Study 1, one signal remained at 80 dB SPL while the other was varied from 30 to 80 dB in 10-dB steps. In Study 2, one ear was held at 50 dB while the other ear's signal was varied from 30 to 80 dB in 5-dB steps. In Study 3, the signals were varied from 30 to 80 dB SPL in 10-dB steps but with equal intensities to the two cars. Eleven subjects were used in each of the former studies and 12 in the latter. Study 1 shows asymmetry in favor of the right-ear messages even when they are 10 dB less intense than the left. Data of Studies 2 and 3 also show asymmetries but in a more complex fashion. [ABSTRACT FROM AUTHOR]

Three normals, three hemispherectomees, and three temporal lobectomees were stimulated dichotically with CVs in the contralateral ear (left ear for normals) always at 75 dB SPL; the ipsilateral ear (right ear for normals) received either a different CV, a 'bleat,' or an envelope-shaped vowel. The ipsilateral ear was stimulated at intensities ranging in 10-dB steps from SRT to 75 dB SPL. Data show that an ipsilateral 'bleat' had suppressive capabilities even with normals, despite little intelligibility of its own. All ipsilateral stimuli suppressed the patients' contralateral ears drastically compared to the normals even if the ipsilateral stimuli were 20-30 dB less intense than the contralateral CVs. The amount of contralateral CV intelligibility loss caused by a simultaneous signal in the ipsilateral ear may be a sign of the latter's 'speechlike' qualities. [ABSTRACT FROM AUTHOR]

Synthetic CVs with V-O-Ts ranging from -30 to +90 msec, were aligned for dichotic presentation according to either onset, transition, V-O-T, 'boundary' and/or combinations thereof. Twenty-four female right-handed subjects, who listened to messages aligned as 'simultaneous' according to those landmarks, generated the following superiority of right ear over left ear: (1) onset (16.3%); (2) onset +V-O-T (12.8%); (3) onset +transition (12.5%); (4) transition (10.7%); (5) 'boundary' +V-O-T (10.6%); (6) all factors aligned (9.0%); (7) V-O-T (9.0%); (8) 'boundary' (7.6%); (9) 'boundary' +transition (5.0%). Over-all intelligibility and laterality effects were not correlated. Unvoiced CVs dominated V-U pairings unless 'boundary' and/or V-O-Ts were aligned; then voiced consonants were more intelligible. 'Lag effect,' where the trailing member of a dichotic pair is more intelligible, was redefined; lag effects were largest when 'boundary' was taken as the reference for simultaneity, and one transition lagged behind another. [ABSTRACT FROM AUTHOR]

Twelve female normal listeners, all right-handed, heard rhyming pairs of (stop+/a/) nonsense syllables dichotically and monotically. Word onsets were simultaneous, then shifted by 15, 30, 60, and 90 msec. Each subject heard 600 pairs. Monotically, the lag-syllable discriminations were poor at all delays with differences leveling off at 30 msec (93% lead vs 19% lag). Dichotically, lag-ear discrimination was roughly 22% better for all lag times when the right ear lagged. [First found by Shankweiler and Studdert-Kennedy, personal communication.] Left-ear lag scores improved and overcame the right-ear advantage only after 30-msec delay. Total right-ear scores for entire dichotic portion of experiment (M=77%) exceeded total left-ear scores (M=66%) thus maintaining an over-all right-ear laterality effect. Thus, previous experimenters who allowed as much as 90-msec delay to be randomly distributed among their so-called 'simultaneous pairs' might still have expected to find a right-ear laterality effect. [Supported in part by NINDS.] [ABSTRACT FROM AUTHOR]