Interaction in planning vocalizations and grasping

Previous studies have shown a congruency effect between manual grasping and syllable articulation. For instance, a power grip is associated with syllables whose articulation involves the tongue body and/or large mouth aperture ([kɑ]) whereas a precision grip is associated with articulations that involve the tongue tip and/or small mouth aperture ([ti]). Previously, this effect has been observed in manual reaction times. The primary aim of the current study was to investigate whether this congruency effect also takes place in vocal responses and to investigate involvement of action selection processes in the effect. The congruency effect was found in vocal and manual responses regardless of whether or not the syllable or grip was known a priori, suggesting that the effect operates with minimal or absent action selection processes. In addition, the effect was observed in vocal responses even when the grip was only prepared but not performed, suggesting that merely planning a grip response primes the corresponding articulatory response. These results support the view that articulation and grasping are processed in a partially overlapping network.     

Change deafness across voices in music and language

ABSTRACT

Listeners made same/different evaluations of a pair of musical presentations separated by a broadband noise. In the first experiment, the pair had either the same or a different: singers voice, language (Spanish or English), and reverberation (dry or very high reverb). A second experiment was conducted using the same vocal melodies played on guitars to emphasize non-linguistic content. In both Experiments 1 and 2, large-scale changes to Reverb were either completely undetected or ignored. A change of language in Experiment 1 supported only minimal sensitivity to change detection. Changes to multiple variables tended to increase listener sensitivity to a stimulus change. The results seem to indicate that the semantic coherence created by a musical background may limit attention to linguistic changes and voicing. Rather, those changes that more directly influence musical quality may be of greater salience in a musical context.     

Listeners' comprehension of uptalk in spontaneous speech

Listeners’ comprehension of phrase final rising pitch on declarative utterances, or uptalk, was examined to test the hypothesis that prolongations might differentiate conflicting functions of rising pitch. In Experiment 1 we found that listeners rated prolongations as indicating more speaker uncertainty, but that rising pitch was unrelated to ratings. In Experiment 2 we found that prolongations interacted with rising pitch when listeners monitored for words in the subsequent utterance. Words preceded by prolonged uptalk were monitored faster than words preceded by non-prolonged uptalk. In Experiment 3 we found that the interaction between rising pitch and prolongations depended on listeners’ beliefs about speakers’ mental states. Results support the theory that temporal and situational context are important in determining intonational meaning.     

The organization of narrative discourse in Lewy body spectrum disorder

Narrative discourse is an essential component of day-to-day communication, but little is known about narrative in Lewy body spectrum disorder (LBSD), including Parkinson’s disease (PD), Parkinson’s disease with dementia (PDD), and dementia with Lewy bodies (DLB). We performed a detailed analysis of a semi-structured speech sample in 32 non-aphasic patients with LBSD, and we related their narrative impairments to gray matter (GM) atrophy using voxel-based morphometry. We found that patients with PDD and DLB have significant difficulty organizing their narrative speech. This was correlated with deficits on measures of executive functioning and speech fluency. Regression analyses associated this deficit with reduced cortical volume in inferior frontal and anterior cingulate regions. These findings are consistent with a model of narrative discourse that includes executive as well as language components and with an impairment of the organizational component of narrative discourse in patients with PDD and DLB.     

Reprint of: stuttering treatment control using P300 event-related potentials

Positron emission tomography studies during speech have indicated a failure to show the normal activation of auditory cortical areas in stuttering individuals. In the present study, P300 event-related potentials were used to investigate possible effects of behavioral treatment on the pattern of signal amplitude and latency between waves. In order to compare variations in P300 measurements, a control group paired by age and gender to the group of stutterers, was included in the study. Findings suggest that the group of stutterers presented a significant decrease in stuttering severity after the fluency treatment program. Regarding P300 measurements, stutterers and their controls presented results within normal limits in all testing situations and no significant statistical variations between pre and post treatment testing. When comparing individual results between the testing situations, stutterers presented a higher average decrease in wave latency for the right ear following treatment. The results are discussed in light of previous P300 event-related potentials and functional imaging studies with stuttering adults.Educational objectives: The reader will learn about and be able to describe the: (1) use of P300 event-related potentials in the study of stuttering; (2) differences between stuttering and non-stuttering adults; and (3) effects of behavioral fluency treatment on cerebral activity in stuttering speakers.     

Dichotic listening and left-right confusion

The present study examined the relationship between individual differences in dichotic listening (DL) and the susceptibility to left-right confusion (LRC). Thirty-six men and 59 women completed a consonant-vowel DL test, a behavioral LRC task, and an LRC self-rating questionnaire. Significant negative correlations between overall DL accuracy and LRC rates in men (behavioral task) and self-ratings in women, indicated that the more participants struggled with left-right discrimination, the fewer DL syllables they reported correctly. However, there was no relationship between LRC and the typical right ear advantage. Thus, there is a sex- and task-dependent relationship between LRC and overall DL accuracy, but not between LRC and ear asymmetry. It is concluded that (a) atypical ear asymmetries, as in certain clinical populations, cannot be explained by associated deficits in left-right discrimination, and (b) LRC can negatively affect task performance, even when participants do not have to make explicit "left" versus "right" decisions.     

Adaptation to novel accents: feature-based learning of context-sensitive phonological regularities

This paper examines whether adults can adapt to novel accents of their native language that contain unfamiliar context-dependent phonological alternations. In two experiments, French participants listen to short stories read in accented speech. Their knowledge of the accents is then tested in a forced-choice identification task. In Experiment 1, two groups of listeners are exposed to newly created French accents in which certain vowels harmonize or disharmonize, respectively, to the rounding of the preceding vowel. Despite the cross-linguistic predominance of vowel harmony over disharmony, the two groups adapt equally well to both accents, suggesting that this typological difference is not reflected in perceptual learning. Experiment 2 further explores the mechanism underlying this type of phonological learning. Participants are exposed to an accent in which some vowels harmonize and others disharmonize, yielding an increased featural complexity. They adapt less well to this regularity, showing that adaptation to novel accents involves feature-based inferences.     

Temporal processing capabilities in repetition conduction aphasia

This study investigates the temporal resolution capacities of the central-auditory system in a subject (NP) suffering from repetition conduction aphasia. More specifically, the patient was asked to detect brief gaps between two stretches of broadband noise (gap detection task) and to evaluate the duration of two biphasic (WN-3) continuous noise elements, starting with white noise (WN) followed by 3 kHz bandpass-filtered noise (duration discrimination task). During the gap detection task, the two portions of each stimulus were either identical (“intra-channel condition”) or differed (“inter-channel condition”) in the spectral characteristics of the leading and trailing acoustic segments. NP did not exhibit any deficits in the intra-channel condition of the gap detection task, indicating intact auditory temporal resolution across intervals of 1–3 ms. By contrast, the inter-channel condition yielded increased threshold values. Based upon the “multiple-looks” model of central-auditory processing, this profile points at a defective integration window operating across a few tens of milliseconds – a temporal range associated with critical features of the acoustic speech signal such as voice onset time and formant transitions. Additionally, NP was found impaired during a duration discrimination task addressing longer integration windows (ca. 150 ms). Concerning speech, this latter time domain approximately corresponds to the duration of stationary segmental units such as fricatives and long vowels. On the basis of our results we suggest, that the patient’s auditory timing deficits in non-speech tasks may account, at least partially, for his impairments in speech processing.     

The power of powerless speech: The effects of speech style and task interdependence on status conferral

Two studies examine the effects of speech styles and task interdependence on status conferral judgments. In both studies, participants were exposed to an individual who used either a powerful or powerless speech style in a low or high task interdependence group, and made judgments about the amount of status to confer to the individual. When task interdependence was low, participants conferred more status to powerful speakers, whereas when interdependence was high, participants conferred more status to powerless speakers. Furthermore, Study 2 demonstrated that speech styles influenced trait inferences about the speaker (agency and communality), but these traits were weighted differently in status conferral judgments across groups. These findings provide insight into both the relationship between observed behaviors and status positions and the decision process underlying status conferral judgments.     

A step forward: Bayesian hierarchical modelling as a tool in assessment of individual discrimination performance

Individual assessment of infants’ speech discrimination is of great value for studies of language development that seek to relate early and later skills, as well as for clinical work. The present study explored the applicability of the hybrid visual fixation paradigm (Houston et al., 2007) and the associated statistical analysis approach to assess individual discrimination of a native vowel contrast, /aː/ - /eː/, in Dutch 6 to 10-month-old infants. Houston et al. found that 80% (8/10) of the 9-month-old infants successfully discriminated the contrast between pseudowords boodup - seepug. Using the same approach, we found that 12% (14/117) of the infants in our sample discriminated the highly salient /aː/ -/eː/ contrast. This percentage was reduced to 3% (3/117) when we corrected for multiple testing. Bayesian hierarchical modeling indicated that 50% of the infants showed evidence of discrimination. Advantages of Bayesian hierarchical modeling are that 1) there is no need for a correction for multiple testing and 2) better estimates at the individual level are obtained. Thus, individual speech discrimination can be more accurately assessed using state of the art statistical approaches.