摘要:

Musicians judged 13 tonal intervals under magnitude estimation instructions. The intervals were spaced in 20‐cent steps and covered a range of three semitone categories. In experiment I, the subjects were naive with respect to the exact nature of the stimulus set, and under these conditions, evidence for categorical perception was obtained. The psychometric functions were well predicted by these subjects identification of the same stimuli. Stimuli in different categories were judged as perceptually distinct, but the judgment of intonation within a category was poor. That is, these subjects were unable to distinguish among sharp, in‐tune, and flat stimuli with the same interval name. In Experiment II, subjects were given specific information concerning the nature of the stimuli. Their judgment of within‐category differences failed to improve, and their assignment of the stimuli to the three interval categories became more variable. It appears that musicians are poor at judging within‐category differences in intonation, and that attempting to do so disrupts the processing of categorical information.

ISSN:0001-4966    

DOI:10.1121/1.2003335

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP

摘要:

The categorical perception of pitch by musicians [e.g., W. Siegel and R. Sopo, J. Acoust. Soc. Am.57, 511 (1975)] raises an interesting question: How can they tune their instruments when they cannot tellsharpfromflat? Here, the results of two experiments on ELP, a musician with very fine absolute pitch, suggest a resolution of the categorization paradox. In a production task, which emulates tuning an instrument, he was very accurate at adjusting the frequency of an oscillator to a value corresponding to four musical notes, g♯ (415 Hz), a (440), c (523), and d♯ (622). However, in an identification task involving listening to single brief notes, he showed striking evidence of categorical perception. That is, he judged 400‐, 500‐, and 600‐Hz tones to be accurate examples of the notes g♯ (415), c (523), and d♯ (622) on most of the trials.

ISSN:0001-4966    

DOI:10.1121/1.2003338

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP

摘要:

Syllable‐like utterances produced by 14 different infants aged 1–40 weeks were presented to two trained listeners. The listeners first transcribed a portion of the data phonetically. They then compared transcriptions, attempted to resolve disagreements and decided upon conventions to be used. One hundred and twenty‐two additional segments were then transcribed by the listeners independently. On 71% of these utterances the listeners disagreed in their transcriptions of syllabic nuclei. The remaining 29%, upon which they agreed, were all transcribed as mid or low front. Their judgments, where they disagreed, were always vowels adjacent to one another within the vowel triangle and were also predominantly heard as mid or low front vowels. The vowels at the extremes of the triangle, /a/, /u/, and /i/ were not judged to be present at all. Ten vowels upon which the judges agreed and ten upon which they disagreed were analyzed by conventional spectrographic and by computer‐assisted spectral techniques. The results of these analyses will be discussed. [Work supported by NINCDS.]

ISSN:0001-4966    

DOI:10.1121/1.2003346

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP

摘要:

Accurate control of vocal tract length is essential for the correct production of vowels. Vertical larynx movement and lip spreading/protrusion, often acting together, are important determinants of vocal tract length. The present study was designed to determine whether constraining lip spreading/protrusion will induce compensatory vertical larynx displacements, particularly on rounded vowels. Upper lip and larynx movement were monitored photoelectrically while French and Mandarin native speakers produced the vowels /i, y, u/ first under normal speech conditions and then with lip activity constrained. In agreement with the findings of Sundberg (1969), Benguerel (1974), and Ewan (1976), there were significant differences during normal speech in upper lip protrusion and larynx position as a function of the vowel and tone uttered, in particular a difference in lip protrusion between /u/ and /y/. Results further reveal that the generally low larynx position of rounded vowels becomes even lower than lip protrusion is constrained. This data has implications for the role of a contrast‐preserving strategy in speech production. [Supported in part by the National Science Foundation. ] Also, Department of Languages and Linguistics, University of Essex, Colchester, England.

ISSN:0001-4966    

DOI:10.1121/1.2003350

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP

摘要:

An investigation was made of the role of voice onset time (VOT) in distinguishing among Korean apical stop consonants. Measurements were made of VOT values for word‐initial apical stops in the speech of four native Korean speakers. Words in citation form, in test sentences, in conversations among Korean adults, and in mothers' speech to children were used. Our results are not in accord with other experimenters who found complete separation of the aspirated from the strong and weak categories of Korean stops. VOT values for word‐initial apical stops in the speech of all four speakers showed considerable overlap of the weak and aspirated categories. The strong and weak categories were also found to overlap, but the overlap in the weak and aspirated categories was greater. Our data suggest that although VOT is sufficient to distinguish the strong from the aspirated stops, it cannot effectively distinguish either of these from the weak stops. Our findings support Kim (1965), who proposes a feature of “tensity,” independent of VOT, to distinguish weak stops from the strong and aspirated stops of Korean.

ISSN:0001-4966    

DOI:10.1121/1.2003359

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP

摘要:

In rhythmic choral speech, all speakers produce the same phonetic message at the same rate. A recording of such speech can be viewed as an algebraic summation in which speaker dependent variability is essentially reduced to the level of background noise. Intelligibility tests and acoustic analyses will be done on recordings of a large group of speakers producing short phrases containing stressed vowels in CVC syllables. The results will be considered in light of two competing theories of perceptual normalization; Kuhn [J. Acoust. Soc. Am.58, 428–433 (1975)] which suggests that front cavity information is invariant across speakers; and the standard formant ratio hypothesis. Preliminary data from a mixed chorus of 30 members indicates that intelligibility is maintained for phrase length utterances, and further that several consonants and most vowels are readily perceptible, even in excised syllables.

ISSN:0001-4966    

DOI:10.1121/1.2003362

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP

摘要:

Piezoelectric polymer (poled polyvinylidene fluoride), a Japanese development recently introduced into high fidelity technology, shows promise as a hydrophone material because of its flexibility, ruggedness, low density, and potentially low cost. A family of lightweight flexural disk hydrophones which use piezoelectric polymer are described. Measurements on a 3.8‐cm‐diam unit gave a sensitivity of −199 dBre1 V/μPa with good stability over ranges of 2 Hz–1 kHz, 0°–22°C, and 0–4 MPa static pressure. This particular unit uses two air‐backed flexural disks with a stack of four pieces of 30‐μm polymer film glued to each disk, resulting in a combined capacitance of 1 nFd. This hydrophone has a mass of 24 g in air and is neutrally buoyant in water. A theoretical analysis which shows the variation of hydrophone performace as a function of design parameters is presented, and the material properties of piezoelectric polymer and piezoelectric ceramic are compared. [Work supported by NAVSEA and NAVELEX.]

ISSN:0001-4966    

DOI:10.1121/1.2003366

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP

摘要:

Pairs of noisebursts (75 dB SPL, 150 msec apart) were presented to subjects who were instructed to judge the duration of one of them (the target) and ignore the other (the conditioner). The two noisebursts could be presented to the same ear (monaural) or to opposite ears (dichotic), and the conditioner could precede or follow the target (forward and backward paradigm, respectively). Subjects estimated target duration by changing the duration of a third noiseburst (also 75 dB SPL) presented 1500 msec after the pair. Five conditioner (5, 10, 20, 40, and 80 msec) and two target durations (20 and 25 msec) were used. In the forward monaural paradigm the average subject selected bursts of 17 and 26 msec as matching the 20 msec target when the conditioner was set at 5 and 80 msec, respectively. The matches showed smaller and more variable shifts in the monaural backward, dichotic forward, and dichotic backward paradigms. These perceptual duration shifts resemble a variety of other auditory illusions, such as loudness enhancement and pitch shifts (R. Elmasian and R. Galambos, J. Acoust. Soc. Am.58, 229–234 (1975);58S83 (1975)] and may be related to them by a common mechanism.

ISSN:0001-4966    

DOI:10.1121/1.2003372

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP

摘要:

We have recently reported that frequency resolution, under conditions of high stimulus uncertainty, is much more accurate for late high‐frequency components than for early, low‐frequency components of word‐length tonal sequences [Watson, Wroton, Kelly, and Benbassat, J. Acoust. Soc. Am.57, 1175–1185 (1975)]. We have now replicated these experiments for the case of temporal resolution. Listeners were tested with high, medium, andminimalstimulus uncertainty until they performed at asymptotic levels of temporal resolution, defined by just‐detectable proportional increments (Δt/t) in the duration of single 40‐msec components of 10‐tone sequences. The duration of late, high‐frequency components is also resolved more accurately than that of early, low‐frequency elements, although the differences are considerably less than for frequency resolution. Asymptotic just‐detectable values of Δt/trange from about 0.75 to 0.15, from high to minimal levels of stimulus uncertainty, suggestive of a shift from detecting increments in tonal sequence duration to detecting increments in the duration of single test components. [Supported by Grant ♯NS‐03856 from NINCDS.]

ISSN:0001-4966    

DOI:10.1121/1.2003375

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP

摘要:

The phenomenon of ear dominance for the pitch of dichotically presented tones has been described in previous publications [Efron and Yund, Neuro‐psychologia12, 249–256 (1974);13, 137–150 (1975);13, 151–161 (1975); Brain and Language3, 246–254 (1976); J. Acoust. Soc. Am.59, 889–898 (1976)]. In these studies on more than 100 normal subjects, the pitch mixture of the perceived dichotic chord was strongly dominated by the frequency presented to the right ear in 10% and by the left ear frequency in another 10%. The remaining subjects (80%) had either a weak or a nonsignificant ear dominance. Subsequent studies on subjects with forebrain commissurotomy [J. Acoust. Soc. Am.59, S53(A) (1976)] indicated that the pitch minute of the dichotic chord was determined by a functional asymmetry in a subcortical pitch processor. The present study with three subjects hemispherectomized in infancy and one at age 13 reveal a strong ear dominance for the ear contralateral to the existing hemisphere in all four subjects. These results suggest that there is efferent control, from the cerebral cortex, on the hypothesized subcortical pitch processor.

ISSN:0001-4966    

DOI:10.1121/1.2003384

出版商:Acoustical Society of America    

年代:1976

数据来源: AIP