Effect of speech task on intelligibility in dysarthria: a case study of Parkinson's disease

This study assessed intelligibility in a dysarthric patient with Parkinson's disease (PD) across five speech production tasks: spontaneous speech, repetition, reading, repeated singing, and spontaneous singing, using the same phrases for all but spontaneous singing. The results show that this speaker was significantly less intelligible when speaking spontaneously than in the other tasks. Acoustic analysis suggested that relative intensity and word duration were not independently linked to intelligibility, but dysfluencies (from perceptual analysis) and articulatory/resonance patterns (from acoustic records) were related to intelligibility in predictable ways. These data indicate that speech production task may be an important variable to consider during the evaluation of dysarthria. As speech production efficiency was found to vary with task in a patient with Parkinson's disease, these results can be related to recent models of basal ganglia function in motor performance.     

Combining gesture with verbal instruction promotes problem-solving skills among young children attempting difficult tasks

Extensive research shows that caregivers’ speech and gestures can scaffold children’s learning. This study examines whether caregivers increase the amount of spoken and gestural instruction when a task becomes difficult for children. We also examine whether increasing the amount of instruction containing both speech and gestures enhances children’s problem-solving. Ninety-three 3- to 4-year-old Chinese children and their caregivers participated in our study. The children tried to assemble two jigsaw puzzles (with 12 pieces in one and 20 in the other); each puzzle was attempted in three phases. The order in which the puzzles were to be solved was randomized. In Phases 1 and 3, the children tried to solve the puzzles alone. In Phase 2, the children received instruction from their caregivers. The children assembled a smaller proportion of the 20-piece puzzle than of the 12-piece one, suggesting that the 20-piece puzzle was more difficult than the 12-piece one. The caregivers produced more spoken and gestural instruction for the 20-piece than for the 12-piece puzzle. The proportion of the instruction employing both speech and gesture (+InstS+InstG) was significantly greater for the 20-piece puzzle than for the 12-piece puzzle. More importantly, the children who received more instruction with +InstS+InstG performed better in solving the 20-piece puzzle than those who received less instruction of the same type. Those who did not receive +InstS+InstG instruction performed less successfully in Phase 3. However, the facilitating effect of instruction with +InstS+InstG was not found with the 12-piece puzzle. Our findings suggest that adults should incorporate speech and gesture in their instruction as frequently as possible when teaching their children to perform a difficult task.     

Muscular Activity in the Arm during Lexical Retrieval: Implications for Gesture-Speech Theories

The origin and functions of the hand and arm gestures that accompany speech production are poorly understood. It has been proposed that gestures facilitate lexical retrieval, but little is known about when retrieval is accompanied by gestural activity and how this activity is related to the semantics of the word to be retrieved. Electromyographic (EMG) activity of the dominant forearm was recorded during a retrieval task in which participants tried to identify target words from their definitions. EMG amplitudes were significantly greater for concrete than for abstract words. The relationship between EMG amplitude and other conceptual attributes of the target words was examined. EMG was positively related to a word’s judged spatiality, concreteness, drawability, and manipulability. The implications of these findings for theories of the relation between speech production and gesture are discussed.This experiment was done by the first author under the supervision of the second author in partial completion of the Ph.D. degree at Columbia University. We gratefully acknowledge the advice and comments of Lois Putnam, Robert Remez, James Magnuson, Michele Miozzo, and Robert B. Tallarico, and the assistance of Stephen Krieger, Lauren Walsh, Jennifer Kim, and Jillian White.     

Self‐reported inner speech use in university students

Remarkably little is known regarding what people talk to themselves about (inner speech use) in their everyday lives. Existing self‐directed speech measures (e.g., thought sampling and questionnaires) either uniquely capture inner speech frequency and neglect its content or classify self‐reported thoughts instances in overly simplistic categories determined by the researchers. In the current study, we describe an open‐format thought listing procedure as well as a refined coding scheme and present detailed inner speech content self‐generated by 76 university students. The most frequently self‐reported inner speech activities were self‐regulation (e.g., planning and problem solving), self‐reflection (e.g., emotions, self‐motivation, appearance, behavior/performance, and autobiography), critical thinking (e.g., evaluating, judging, and criticizing), people in general, education, and current events. Inner speech occurred most commonly while studying and driving. These results are consistent with the self‐regulatory and self‐referential functions of inner speech often emphasized in the literature. Future research avenues using the open‐format inner speech listing procedure and coding scheme are proposed.     

From Figure to Argument: <Emphasis Type="Italic">Contrarium</Emphasis> in Roman Rhetoric

In Roman rhetoric, contrarium was variably considered either a figure of speech or an argument. The paper examines the logical pattern of this type of argument, which according to Cicero is based on a third Stoic indemonstrable syllogism: The persuasiveness of this type of argument, however, vitally depends on the validity of the alleged ‹incompatibility’ forming its major premiss. Yet this appears to be the argument’s weak point, as the ‹incompatibilities’ employed generally hold for the most part only, and are reducible to topical argument schemes. This is why in practical usage such arguments are most often phrased as rhetorical questions, the persuasive force of which, enhanced by certain strategical maneuverings and fallacies, makes the audience swallow the argument.     

Cross-channel amplitude sweeps are crucial to speech intelligibility

Classical views of speech perception argue that the static and dynamic characteristics of spectral energy peaks (formants) are the acoustic features that underpin phoneme recognition. Here we use representations where the amplitude modulations of sub-band filtered speech are described, precisely, in terms of co-sinusoidal pulses. These pulses are parameterised in terms of their amplitude, duration and position in time across a large number of spectral channels. Coherent sweeps of energy across this parameter space are identified and the local transitions of pulse features across spectral channels are extracted. Synthesised speech based on manipulations of these local amplitude modulation features was used to explore the basis of intelligibility. The results show that removing changes in amplitude across channels has a much greater impact on intelligibility than differences in sweep transition or duration across channels. This finding has severe implications for future experimental design in the fields of psychophysics, electrophysiology and neuroimaging.     

The multidimensional nature of hyperspeech: Evidence from Japanese vowel devoicing

We investigate the hypothesis that infant-directed speech is a form of hyperspeech, optimized for intelligibility, by focusing on vowel devoicing in Japanese. Using a corpus of infant-directed and adult-directed Japanese, we show that speakers implement high vowel devoicing less often when speaking to infants than when speaking to adults, consistent with the hyperspeech hypothesis. The same speakers, however, increase vowel devoicing in careful, read speech, a speech style which might be expected to pattern similarly to infant-directed speech. We argue that both infant-directed and read speech can be considered listener-oriented speech styles—each is optimized for the specific needs of its intended listener. We further show that in non-high vowels, this trend is reversed: speakers devoice more often in infant-directed speech and less often in read speech, suggesting that devoicing in the two types of vowels is driven by separate mechanisms in Japanese.