“Perceptual centers” in speech production and perception

Morton, Marcus, and Frankish (1976) report that listeners hear acoustically isochronous digit sequences as anisochronous. Moreover, given a chance to adjust intervals in the sequences until they are perceptually isochronous, the listeners introduce systematic deviations from isochrony. The present series of studies investigates these phenomena further. They indicate that when asked toproduce isochronous sequences, talkers generate precisely the acoustic anisochronies that listeners require in order tohear a sequence as isochronous. The acoustic anisochronies that talkers produce are expected if talkers initiate the articulation of successive items in the sequence at temporally equidistant intervals. Items whose initial consonants differ in respect to manner class will have acoustic consequences (other than silence) at different lags with respect to their articulatory onsets thereby generating the observed acoustic anisochronies. The findings suggest that listeners judge isochrony based on acoustic information aboutarticulatory timing rather than on some articulation-free acoustic basis.     

A “labial” feature analyzer in speech perception

A selective adaptation experiment was conducted to determine the ability of various adapting stimuli to alter the perception of a series of 13 synthetic speech syllables. The synthetic test syllables, which varied acoustically in the starting frequency and direction of second- and third-formant transitions, included stop consonant distinctions ofplace of articulation for the syllable types [bae], [dae], and [gae]. A systematic adaptation effect was produced in the locus of the bae-bae phonetic boundary for these stimuli after repetitive listening to each of the following adapting syllables: [bae], [p^hae], [mae], and [vae], indicating that perception ofplace distinctions among the stop consonants can be altered even by repetitive listening to certain speech sounds not belonging to the stop-consonant class.     

Infant directed speech and the development of speech perception: Enhancing development or an unintended consequence?

Infant directed speech (IDS) is a speech register characterized by simpler sentences, a slower rate, and more variable prosody. Recent work has implicated it in more subtle aspects of language development. Kuhl et al. (1997) demonstrated that segmental cues for vowels are affected by IDS in a way that may enhance development: the average locations of the extreme “point” vowels (/a/, /i/ and /u/) are further apart in acoustic space. If infants learn speech categories, in part, from the statistical distributions of such cues, these changes may specifically enhance speech category learning. We revisited this by asking (1) if these findings extend to a new cue (Voice Onset Time, a cue for voicing); (2) whether they extend to the interior vowels which are much harder to learn and/or discriminate; and (3) whether these changes may be an unintended phonetic consequence of factors like speaking rate or prosodic changes associated with IDS. Eighteen caregivers were recorded reading a picture book including minimal pairs for voicing (e.g., beach/peach) and a variety of vowels to either an adult or their infant. Acoustic measurements suggested that VOT was different in IDS, but not in a way that necessarily supports better development, and that these changes are almost entirely due to slower rate of speech of IDS. Measurements of the vowel suggested that in addition to changes in the mean, there was also an increase in variance, and statistical modeling suggests that this may counteract the benefit of any expansion of the vowel space. As a whole this suggests that changes in segmental cues associated with IDS may be an unintended by-product of the slower rate of speech and different prosodic structure, and do not necessarily derive from a motivation to enhance development.     

“Moving to the beat” improves timing perception

Here, we demonstrate that “moving to the beat” can improve the perception of timing, providing an intriguing explanation as to why we often move when listening to music. In the first experiment, participants heard a series of isochronous beats and identified whether the timing of a final tone after a short silence was consistent with the timing of the preceding sequence. On half of the trials, participants tapped along with the beat, and on half of the trials, they listened without moving. When the final tone occurred later than expected, performance in the movement condition was significantly better than performance in the no-movement condition. Two additional experiments illustrate that this improved performance is due to improved timekeeping, rather than to a shift in strategy. This work contributes to a growing literature on sensorimotor integration by demonstrating body movement’s objective improvement in timekeeping, complementing previous explorations involving subjective tasks.     

Tracking the speech signal – Time-locked MEG signals during perception of ultra-fast and moderately fast speech in blind and in sighted listeners

Blind people can learn to understand speech at ultra-high syllable rates (ca. 20 syllables/s), a capability associated with hemodynamic activation of the central-visual system. To further elucidate the neural mechanisms underlying this skill, magnetoencephalographic (MEG) measurements during listening to sentence utterances were cross-correlated with time courses derived from the speech signal (envelope, syllable onsets and pitch periodicity) to capture phase-locked MEG components (14 blind, 12 sighted subjects; speech rate = 8 or 16 syllables/s, pre-defined source regions: auditory and visual cortex, inferior frontal gyrus). Blind individuals showed stronger phase locking in auditory cortex than sighted controls, and right-hemisphere visual cortex activity correlated with syllable onsets in case of ultra-fast speech. Furthermore, inferior-frontal MEG components time-locked to pitch periodicity displayed opposite lateralization effects in sighted (towards right hemisphere) and blind subjects (left). Thus, ultra-fast speech comprehension in blind individuals appears associated with changes in early signal-related processing mechanisms both within and outside the central-auditory terrain.     

Cortical asymmetries in speech perception: what's wrong,what's right and what's left?

Over the past 30 years hemispheric asymmetries in speech perception have been construed within a domain-general framework, according to which preferential processing of speech is due to left-lateralized, non-linguistic acoustic sensitivities. A prominent version of this argument holds that the left temporal lobe selectively processes rapid/temporal information in sound. Acoustically, this is a poor characterization of speech and there has been little empirical support for a left-hemisphere selectivity for these cues. In sharp contrast, the right temporal lobe is demonstrably sensitive to specific acoustic properties. We suggest that acoustic accounts of speech sensitivities need to be informed by the nature of the speech signal and that a simple domain-general vs. domain-specific dichotomy may be incorrect.     

Obligatory “expectations” of expressive timing induced by perception of musical structure

Previous research has shown that, in a task requiring the detection of local deviations from mechanically precise timing in music, the relative detectability of deviations in different positions is closely related to the typical expressive timing pattern musicians produce when playing the music. This result suggests that listeners expect to hear music expressively timed and compensate for the absence of expressive timing. Three new detection experiments shed additional light on the nature of these timing expectations in musically trained listeners. Experiment 1 shows that repeated exposure to an atypically (but not unmusically) timed performance leaves listeners' timing expectations unaffected. Experiment 2 demonstrates that the expectations do not manifest themselves when listeners merely imagine the music in synchrony with a click track. Experiment 3, however, shows that the timing expectations are fully operational when the click track is superimposed on the music. These results reveal timing “expectations” to be an obligatory consequence of the ongoing auditory perception of musical structure. Received: 5 November 1996 / Accepted: 26 February 1997     

Assessing the role of orthography in speech perception and production: Evidence from picture–word interference tasks

The effects of orthographic and phonological relatedness between distractor word and object name in a picture–word interference task were investigated. In Experiment 1 distractors were presented visually, and consistent with previous findings, priming effects arising from phonological overlap were modulated by the presence or absence of orthographic similarity between distractor and picture name. This pattern is interpreted as providing evidence for cascaded processing in visual word recognition. In Experiment 2 distractors were presented auditorily, and here priming was not affected by orthographic match or mismatch. These findings provide no evidence for orthographic effects in speech perception and production, contrary to a number of previous reports.     

Perceptual magnet and phoneme boundary effects in speech perception: do they arise from a common mechanism?

The question of whether sensitivity peaks at vowel boundaries (i.e., phoneme boundary effects) and sensitivity minima near excellent category exemplars (i.e., perceptual magnet effects) stem from the same stage of perceptual processing was examined in two experiments. In Experiment 1, participants gave phoneme identification and goodness ratings for 13 synthesized English /i/ and /e/ vowels. In Experiment 2, participants discriminated pairs of these vowels. Either the listeners discriminated the entire range of stimuli within each block of trials, or the range within each block was restricted to a single stimulus pair. In addition, listeners discriminated either one-step or two-step intervals along the stimulus series. The results demonstrated that sensitivity peaks at vowel boundaries were more influenced by stimulus range than were perceptual magnet effects; peaks in sensitivity near the /i/-/e/ boundary were reduced with restricted stimulus ranges and one-step intervals, but minima in discrimination near the best exemplars of /i/ were present in all conditions.     

New evidence for “closure” in perception

A new criterion of perceptual grouping (Gillam, 1972), namely, that contours appear to reverse together under conditions of depth ambiguity, was used to test for the reality of “closure” and explore the parameters determining its degree. It was found that contours which would form a closed space but for a linear gap were responded to as a unit to a degree which decreased monotonically with gap size. Neither “proximal” nor “distal” gap was found to be the sole determinant of closure. Several levels of processing appear to be involved.

     

Variations in an African Grey parrot’s speech patterns following ignored and denied requests

Communicative competence is one measure of an individual’s ability to navigate conversations with social partners. The current study explored the possibility of basic communicative competence in a non-mammal speaker, a speech-using African Grey parrot. Spontaneous conversations between one Grey named Cosmo and her caregiver were recorded, from which three corpora (i.e., bodies of text) of Cosmo’s vocalizations were developed: (1) Baseline: Vocalizations containing no requests, (2) Ignored Requests: Vocalizations immediately following Cosmo’s caregiver ignoring Cosmo’s requests, and (3) Denied Requests: Vocalizations immediately following Cosmo’s caregiver denying Cosmo’s requests. The distributions of social (e.g., “I love you,” kiss sounds) and nonsocial (e.g., answering machine beeps, “That’s squirrel”) vocalizations, as well as speech and nonword vocalizations, were statistically different across the three corpora. Additionally, qualitative analysis of the datasets indicated Cosmo was persistent in repeating vocalizations when denied and ignored, and interrupted her caregiver more often when requests were denied compared to ignored. Neither repetition nor interruption occurred during the Baseline conversations. The data indicate that despite the outcome being the same (i.e., request was unmet), Cosmo treated an ignored request differently than a denied request, modifying her vocalizations in accord with the specific context. Such modification is evidence of basic communicative competence.     

Transference and countertransference in an applied setting — education

This paper offers an overview of current clinical approaches to psychoanalytically informed work with parents by child psychotherapists. The analysis is based on practice at the Tavistock Clinic and on broader knowledge of trends in work with children and families within the National Health Service. A brief history sets the scene. Four varieties of approach are described, with clinical examples. The particular sensitivity of child psychotherapists to infantile features in the personality is highlighted, and it is argued that this, together with their broad clinical experience, provides a proper basis for psychoanalytic psychotherapy with parents. Such work significantly extends and enriches the clinical contribution of child psychotherapists and has involved a shift in professional identity. It also raises ethical issues which are discussed.     

Some Reasons for Distinguishing Between “Non-normative Response” and “Irrational Decision”

Three concerns that limit the implications of normative decision research were described in this study. First, because there is no unequivocal way to determine whether any particular base rate is appropriate in a particular instance, the significance of the apparent base rate underutilization reported by a number of investigators is unclear. Second, because there are discrepancies between natural language and formal logic, word problems are an uncertain domain within which to gauge human inferential skills. Third, because different people will have different strategies and preferences, no single solution may be correct or optimal for all persons. In light of these limitations, a more functional approach to decision interpretation is discussed.     

The possible connection between “private speech” and prayer

The purpose of this paper is to investigate the psychological origins of prayer through a preliminary examination of certain aspects of social and cognitive development in early childhood. Specifically, it is the thesis of this essay that the phenomenon of “private speech” in early childhood can tell us something about prayer activity as it occurs in older persons. It is not the intention of this essay to present a detailed or complete theology of prayer from the perspective of pastoral theology or pastoral care. This essay is a prolegomena to the future study of the origins of prayer as social communication and personal regulation.     

The role of “chirp” identification in duplex perception

Duplex perception occurs when the phonetically distinguishing transitions of a syllable are presented to one ear and the rest of the syllable (the “base”) is simultaneously presented to the other ear. Subjects report hearing both a nonspeech “chirp” and a speech syllable correctly cued by the transitions. In two experiments, we compared phonetic identification of intact syllables, duplex percepts, isolated transitions, and bases. In both experiments, subjects were able to identify the phonetic information encoded into isolated transitions in the absence of an appropriate syllabic context. Also, there was no significant difference in phonetic identification of isolated transitions and duplex percepts. Finally, in the second experiment, the category boundaries from identification of isolated transitions and duplex percepts were not significantly different from each other. However, both boundaries were statistically different from the category boundary for intact syllables. Taken together, these results suggest that listeners do not need to perceptually integrate F2 transitions or F2 and F3 transition pairs with the base in duplex perception. Rather, it appears that listeners identify the chirps as speech without reference to the base.     

Making global news: “Freedom of speech” and “Muslim rage” in U.S. journalism

The American press began to take notice of the Danish cartoons after they began to circulate outside of Europe. The press primarily framed the events as a single problem of global interaction: an issue of ‘freedom of speech’ opposed to ‘religious sensitivity.’ Much of the coverage permitted, within limits, a plurality of voices. Drawing on a case study of stories about the ‘cartoon controversy’ in the Boston Globe, I argue that U.S. journalism is organized by a logic of objectivity that seeks to produce a ‘perspectiveless perspective on all perspectives’ (Bourdieu, On television. New York: The New Press, 1998), showing voices on ‘both sides,’ simultaneously masked and contributed to the press’s reifying a series of events into a single global ‘event,’ one that reflected a clash of Western and Islamic values.

“SLANG”—Sensitive Language and the New Genetics—an Exploratory Study

SLANG—Sensitive Language and the New Genetics—is a concept that arose out of informal discussions between a number of interested parties, both consumers and professionals, who were becoming increasingly uneasy with some of the language commonly used in medical genetics. Some language choices were felt by the authors to be inappropriate for a variety of reasons. Poor language choice may impede an individual's understanding of a genetic condition or important medical information and the chosen words themselves may simply be perceived as discriminatory and even offensive. SLANG is an important concept to explore partly because literature in this area confirms that language choices in medical settings can be of great significance to both patients and families. Studies have shown how language choices impact on professional practice by, as one example, changing the intended meaning of medical information and affecting individual perception of risk and choice which, in turn, may affect individual or familial well-being. In addition language choice has the power to affect how individuals perceive themselves and are viewed by others. This paper presents the results from our pilot study and discusses the implications for health professionals with particular reference to medical genetics settings.