Biomedical subjects

B S Rosner

Publications and source records attributed to B S Rosner.

At least 19 recordsLinked to original sources

PubMed1989

Could temporal order differences underlie 2-month-olds' discrimination of English voicing contrasts?

Previous studies have shown that infants discriminate voice onset time (VOT) differences for certain speech contrasts categorically. In addition, investigations of nonspeech processing by infants also yield evidence of categorical discrimination of temporal-order differences. These findings have led some researchers to argue that common auditory mechanisms underlie the infant's discrimination of timing differences in speech and nonspeech contrasts [e.g., Jusczyk et al., J. Acoust. Soc. Am. 67, 262-270 (1980)]. Nevertheless, some discrepancies in the location of the infant's category boundaries for different kinds of contrasts have been noted [e.g., Eilers et al. (1980)]. Because different procedures were used to study the different kinds of contrasts, interpretation of the discrepancies between the studies has been difficult. In the present study, three different continua were examined: [ba]-[pa] stimuli, which differed in VOT; [du]-[tu] stimuli, which differed in VOT but which lacked format transitions; nonspeech formant onset time (FOT) stimuli that varied in the time that lower harmonics increased in amplitude. An experiment with adults indicated a close match between the perceptual boundaries for the three series. Similarly, tests with 2-month-old infants using high amplitude sucking procedure yielded estimates of perceptual category boundaries at between 20 and 40 ms for all three stimulus series.

Arousal↗

PubMed1984

Perception of voice-onset-time continua: a signal detection analysis.

An absolute identification task and various discrimination tasks were performed on synthetic syllables initiated by alveolar stops varying in voice-onset-time (VOT). Signal detection analyses of the data yielded three main findings. First, discrimination d's exceeded those for absolute identification. Greater instability of judgment in the latter than in the former task explained this difference. Second, stimuli within a phonetic category were discriminable, even in a delayed 2IAX paradigm with 4s between stimuli. Third, a category boundary effect appeared: identification and discrimination d's were largest around the voiced/voiceless boundary for alveolar stops. The relationship between discrimination and identification d's varies with response constraints, the number of just noticeable differences in the stimulus array, and stability of judgments in the various tasks. Nearly equal performance in discrimination and identification tasks is not a sufficient condition for a category boundary effect to occur. Several arguments are advanced against a dual-coding model. A continuous model which invokes only a single decision process may account more gracefully for the relationship between identification and discrimination of both consonants and vowels.

Humans↗

PubMed1979

The response of neonates to intra-uterine sounds.

Playing prerecorded intra-uterine sounds to newborns reportedly soothes the babies. This study investigates this claim, particularly because of its promise for identifying neonates with severe hearing losses. 60 babies, up to eight days old, were observed individually under two conditions. In one, activity was rated on the Brazelton scale before and during presentation of intra-uterine sounds. In another, similar ratings were made but no sounds presented. The results indicate that intra-uterine sounds calm 90 per cent of babies who are fussy or crying but have no evident effect on babies who are awake but merely alert or who are slightly drowsy. These findings are discussed and improvements in procedure are suggested for use of intra-uterine sounds in routine screening for severe neonatal hearing loss.

Female↗

PubMed1976