Previous motor and perceptual tasks have found optimal processing for sound sequences of a rate of around 600 msec. IOI (Interonset Interval). This zone of optimal processing (the rate at which discrimination is optimal) slows with age and is also found with infants. The current work investigated whether listeners “prefer” sequences at the rate for which they demonstrate optimal processing. In the present study, three experiments were done. Exp. 1 measured tempo preferences in adults who listened to pairs of isochronous sound sequences varying in tempo (from 100- to 1500-msec. IOI) and were required to indicate which they preferred. As expected, highest preferences were expressed for the intermediate tempi, supporting the hypothesis of a zone of preferred tempi comparable to the zone of optimal processing. Moreover, this preference for intermediate tempi was not affected by the temporal context (absence of differences between a fast, a slow, and a wide set of tempi). In Exp. 2, the same procedure was applied to 6- and 10-yr.-olds. Children in both groups had systematic preferences for the fastest tempi within a set, and the older children generally preferred slower sequences. Exp. 3 used a preference paradigm for sound sequences with 4-mo.-old infants, comparing sequences of 100- vs 300-msec. IOI, 300- vs 900-msec. IOI, and 100- vs 900-msec. IOI. No systematic tempo preferences were observed. We conclude that tempo discrimination and tempo preference may have some commonality (perhaps related to a zone of optimal processing), especially in adults, but that they also involve quite distinct processes which undergo different developmental sequences. Whereas adults prefer what they process the best, children prefer what is fastest (and therefore more attention-getting), and we have not been able to detect preferences in infants.

Résumé Cette revue de questions présente les connaissances actuelles concernant le développement de l'audition, depuis la naissance et pendant l'enfance, pour les capacités de base (seuils absolus, seuils différentiels d'intensité et de fréquence, résolution fréquentielle, localisation, acuité temporelle), et pour des activités impliquant une organisation auditive (groupements, organisation de séquences en flux, perception du tempo, de la mélodie). Les interprétations concernant l'origine d'une immaturité à la naissance de certaines de ces capacités (en particulier des seuils auditifs) sont discutées, et les recherches utilisant différentes méthodes et obtenant des résultats plus ou moins contradictoires sont mises en perspective. Les lacunes des connaissances disponibles sont relevées afin de donner un outil de travail et de réflexion au lecteur intéressé par ces problématiques. Mots-clés : audition, psychoacoustique, développement, bébé, enfant.

This review presents the data currently available, which have considerably grown since twenty years, on the development of audition from birth and during childhood. First, basic abilities are screened : absolute thresholds, differential intensity and frequency thresholds, frequency resolution, localization, temporal acuity are presented successively. Recent interpretations concerning the immaturity of some of these abilities which seems to persist several years (specially auditory thresholds) are discussed. The discrepancies between results obtained in several studies are noted : population differences (particularly on age), and metholodogical differences (specially electrophysiological versus behavioral). Most of current research, in infants as in, adults, concerns the promising topic of auditory organization : infants' abilities in complex auditory perception of sequences, which implies sequential and temporal integration, seem to be accurate very precociously. The main data in grouping, streaming, tempo and melodic perception are presented. Nevertheless, infants' and childrens' auditory perception is still very incomplete. For Each topic, contradictions and gaps are indicated, to foster further research and reflections.

In the analysis of liquids, a whole liquid sample is absorbed onto an absorbent and porous sample carrier, such as a filter paper, and is then traversed by an eluting fluid to carry away one or more constituents of interest for analysis. Elution is preferably carried out under pressure. A sample holder comprises a simple plug and socketed body which are adapted to receive in clamping engagement therebetween a rigid plate of porous material, which acts as a support for a sample carrier.

This paper is divided into three sections. The first section is theoretical; it extends Dynamic Attending Theory (Jones, M. R. Psychological Review 83 (1976) 323; Jones, M. R. Perception and Psychophysics 41(6) (1987) 631; Jones, M. R. Psychomusicology 9(2) (1990) 193; Jones, M. R., & Boltz, M. Psychological Review 96(3) (1989) 459) to developmental questions concerning tempo and time hierarchies. Generally Dynamic Attending Theory proposes that, when listening to a complex auditory sequence, listeners spontaneously focus on events occurring at an intermediate rate (the referent level), and they then may shift attention to events occurring over longer or shorter time spans, that is at lower (faster) or higher (slower) hierarchical levels (focal attending). The second section of the paper is experimental. It examines maturational changes of three dynamic attending activities involving referent period and level, attunement, and focal attending. Tasks involve both motor tapping (including spontaneous motor tempo and synchronization with simple sequences and music) and tempo discrimination. We compare performances by 4-, 6-, 8-, and 10-year-old children and adults, with or without musical training. Results indicate three changes with increased age and musical training: (1) a slowing of the mean spontaneous tapping rate (a reflection of the referent period) and mean synchronization rate (a reflection of the referent level), (2) enhanced ability to synchronize tapping and discriminate tempo (improved attunement), and (3) an enlarged range of tapping rates towards slower rates and higher hierarchical levels (improved focal attending). A final section considers results in light of the theory proposed here. It is suggested that growth trends can be expressed in terms of listeners' engagement of slower attending oscillators with age and experience, accompanied by the passage from the initial use of a single oscillator towards the coupling of multiple oscillators.

An habituation/dishabituation paradigm demonstrates that 2- and 4-month-old infants are able to discriminate auditory sequences that vary slightly in tempo. Discriminations were only observed for intermediate tempi (600 ms but not 100, 300, 1500 ms IOI), suggesting that infants have the same optimal tempo range as adults.

Current research in the field of time perception has been greatly influenced by pioneering investigations carried out over the last fifty years by Paul Fraisse. We demonstrate how contemporary models of auditory perception and cognition, in particular the Dynamic Attending Theory proposed by Jones and Boltz (1989), incorporate several of his ideas and experimental findings. This theory models how listeners are able to follow complex auditory sequences in real time by extracting temporal regularities from what they have already heard and by using this information to create expectations about what will happen in the future. Future events that correspond to these expectations are processed preferentially. We provide new experimental evidence in favor of two predictions that derive from this theory about how these abilities are acquired. First, we demonstrate that younger children focus spontaneously on faster occurring events than older children or adults. Second, we show that older children become increasingly able to focus on events occurring at rates further from their spontaneous referent level. The implications of these results for models of auditory perception and cognition are discussed.

Résumé Les idées et les données expérimentales de Paul Fraisse sur la perception du temps ont considérablement influencé les recherches actuelles sur la cognition auditive. Nous illustrons comment le modèle de l'attention dynamique de Jones et Boltz (1989) les ont intégrées, en testant deux prédictions sur l'acquisition des compétences temporelles : 1/ les jeunes enfants et les bébés se focalisent spontanément sur des événements se produisant à une cadence plus rapide que les enfants plus âgés ou les adultes; 2/ les enfants plus âgés deviennent progressivement capables de focaliser leur attention sur des événements se produisant à des cadences plus éloignées de leur niveau de focalisation spontané. Mots-clés: sensibilité temporelle, organisation temporelle auditive, développement.

The present experiment tested the tempo discrimination abilities of four month-old infants, as a function of tempo range, to investigate whether a similar range of tempo sensitivity is found in infants as in adults. Isochronous auditory sequences were presented with a tempo of 100, 300 or 600 ms inter-onset interval (IOI). Infants were conditioned to associate the auditory sequence and a red light. In an habituation phase, sequences of equal IOI were presented successively, until an habituation criterion was reached. Then for the next three trials, 24 infants (mean age 4;7) heard a sequence with a 15% faster IOI, and the control group of 15 infants (mean age 4;18) heard the unchanged standard IOI. A reaction to novelty, expressed by longer visual fixations to the light was expected in the experimental group if the two tempi were discriminated. The results show that infants are sensitive to a 15% IOI increment for habituation IOI of 300 and 600 ms, but not for 100 ms IOI. Infants discriminate isochronous sequences on the basis of tempo variations, in the same tempo range as adults. These data support the hypothesis that regularity extractor mechanisms are functional at the age of 4 months

Simple loudness adaptation was measured for a steady tone presented alone at 10 dB SL; contralaterally induced adaptation was measured for a steady tone in one ear accompanied by an intermittent tone in the contralateral ear; ipsilaterally induced adaptation was measured for a tone increased intermittently by 15 dB. The method of successive magnitude estimation revealed no differences between 12 adults and 36 children from 9 to 14 years of age in the amounts of adaptation over a 3-min exposure. A second set of experiments with a new group of 20 adults and 20 children used a Bekesy tracking procedure to reach similar results. Unlike Karja [Acta Oto-Laryngol 1968; (suppl)241:1-56], who found significant adaptation in only 5 of 29 children and much adaptation in most adults, we found considerable adaptation in children as well as in adults.

The study aimed at understanding the loudness memory and especially at testing the hypothesis that the loudness contour of a tone sequence influences differential sensitivity -over a long lapse of time- in the domain of intensity. In the first experiment, the loudness of a first reference tone had to be reproduced after a delay (.5, 2, 10, or 20 s) by adjusting the level of a second tone. Errors of adjustment depended on the initial level of the second tone and on the delay. In the second experiment, subjects compared two tones separated by silences. For delays of .5 and 2s, the best performance was found for comparison levels equal to or lower than the reference. In the third experiment, the tones to be compared were separated by 6 interpolated tones at different levels. For sequences with increasing and decreasing levels, the opposite shifts of sensitivity which were observed could explain the adjustment bias of the first experiment. Moreover, only interpolated contours having components at least 6 dB higher than the reference provide a significant impairment of the performance. These results suggest a “retroactive masking” of the memorized trace by subsequent louder sounds.

Differential thresholds for 11 tempi (ranging from 100 to 1500 ms between successive onsets) were measured for four subjects using a 2AFC paradigm. In a first experiment, the number of events in the sequence was varied to test whether sensitivity is greater in regularsequences than in simple duration discrimination tasks (only two events). Relative jnd were: (1) optimal at intermediate tempi (as low as 1.5% in the range between 300–800 ms), and (2) decreased as the number of events increased (2 events=6%, 3 events=4%, 5 events=3.2%, 7 events=3%). A second experiment tested whether this higher sensitivity was due to the fact that the sequences were regular or not by measuring differential tempo thresholds for irregular sequences of five events. Globally, sensitivity for these irregular sequences was of an intermediate level between that of the simple duration task and the sequences with five regular events. The results are discussed in terms of the hypothesized ‘‘regularity detectors.’’

Measurements of simple and induced loudness adaptation were made on 10–12 musicians and 10–12 nonmusicians by the method of successive magnitude estimations. Simple adaptation (SA) was measured for a 500-, 1000-, or 4000-Hz tone presented monaurally for 3 min at 10 dB SL. Induced adaptation was measured for a continuous 1000-Hz, 60-dB SPL right-ear tone; loudness was judged before, during, and after each occurrence of an intermittent inducer tone set to five frequencies from 500–3260 Hz and presented every 30 s for 10 s to the same ear (ipsilaterally induced adaptation, IIA) or to the left ear (contralaterally induced adaptation, CIA). We also measured CIA with a rapid intermittency of every 1 s for 0.5 s. The level of the inducer was 60 dB for CIA and 75 dB for IIA. Musicians showed less adaptation than nonmusicians whatever the type of adaptation: For the musicians, the maximum loudness decrease was 44% under SA, 30% under CIA, 30% under IIA; for the nonmusicians, this maximum was 70% under SA, 70% under CIA, 41% under IIA, but differences were statistically significant only for SA and for CIA with the rapid intermittency. Moreover, musicians showed significant adaptation over a less extended range of frequencies than nonmusicians.

An intermittent tone in one ear may induce a large decline in the loudness of a continuous tone in the contralateral ear [Botte et al., J. Acoust. Soc. Am. 72, 727-739 (1982)]. To uncover the basis for this induced loudness adaptation, the method of successive magnitude estimations was used to measure the loudness of a test tone in one ear during and after a single presentation of a brief inducer tone in the contralateral ear. Duration and frequency of the inducer were varied. The frequency of the test tone was set at 500, 1000, or 3000 Hz. Both inducer and test tones were at 60 dB SPL. When the inducer lasted 5 s or more and was at the same frequency as the test tone, the loudness of the test tone was reduced by 80% to 100% while the inducer was on. As the inducer frequency moved away from the test tone, the loudness reduction declined gradually except for a more marked drop at the point where the frequency separation exceeded the critical bandwidth. Loudness remained depressed after the inducer went off. Additional measurements showed that the amount of loudness reduction corresponded closely to the measured movement of the inducer's sound image away from the center of the listener's head (decentralization).