Heidi Martens

Interpretations of quantum mechanics, joint measurement of incompatible observables, and counterfactual definiteness

The validity of the conclusion to the nonlocality of quantum mechanics, accepted widely today as the only reasonable solution to the EPR and Bell issues, is questioned and criticized. Arguments are presented which remove the compelling character of this conclusion and make clear that it is not the most obvious solution. Alternative solutions are developed which are free of the contradictions related with the nonlocality conclusion. Firstly, the dependence on the adopted interpretation is shown, with the conclusion that the alleged nonlocality property of the quantum formalism may have been reached on the basis of an interpretation that is unnecessarily restrictive. Secondly, by extending the conventional quantum formalism along the lines of Ludwig and Davies it is shown that the Bell problem may be related to complementarity rather than to nonlocality. Finally, the dependence on counterfactual reasoning is critically examined. It appears that locality on the quantum level may still be retained provided one accepts a newly proposed principle of nonreproducibility at the individual quantum level as an alternative of quantum nonlocality. It is concluded that the locality principle can retain its general validity, in full conformity with all experimental data.

Assessment of Prosodic Communicative Efficiency in Parkinson's Disease As Judged by Professional Listeners

This study examines the impact of Parkinsons disease (PD) on communicative efficiency conveyed through prosody. A new assessment method for evaluating productive prosodic skills in Dutch speaking dysarthric patients was devised and tested on 36 individuals (18 controls, 18 PD patients). Three professional listeners judged the intended meanings in four communicative functions of Dutch prosody: Boundary Marking, Focus, Sentence Typing, and Emotional Prosody. Each function was tested through reading and imitation. Interrater agreement was calculated. Results indicated that healthy speakers, compared to PD patients, performed significantly better on imitation of Boundary Marking, Focus, and Sentence Typing. PD patients with a moderate or severe dysarthria performed significantly worse on imitation of Focus than on reading of Focus. No significant differences were found for Emotional Prosody. Judges agreed well on all tasks except Emotional Prosody. Future research will focus on elaborating the assessment and on developing a therapy programme paralleling the assessment.

The Bell inequalities and the joint measurement of incompatible observables

A quantum-mechanical theory of joint nonideal measurement of incompatible polarization observables is applied to an EPR-like experiment. It is demonstrated that this experiment yields both information satisfying and information violating the Bell inequalities. The measurement is also discussed in the context of a local hidden-variables theory. It is argued that the violation of an additional assumption of reproducibility of the hidden variable rather than violation of locality may be responsible for the violation of the Bell inequalities.

Reception of Communicative Functions of Prosody in Hypokinetic Dysarthria due to Parkinson’s Disease

BACKGROUND Mapping adequacy of receptive prosodic abilities in speakers with hypokinetic dysarthria due to Parkinsons disease (PD) is useful, because therapy of disturbed production of prosody relies on adequate reception of prosody. There is evidence for a deficit of reception of emotional prosody in PD. OBJECTIVE The present study aims at presenting a comprehensive picture of the reception of various communicative functions of prosody in hypokinetic dysarthria due to PD. METHODS We assessed perception (using a discrimination task) and comprehension (using an identification task) of five communicative functions of Dutch prosody (lexical stress, boundary marking, focus, sentence mode, and emotional prosody) in a group of adults with hypokinetic dysarthria due to PD (n = 22) and a gender and age matched group of unimpaired adults (n = 22). We also investigated the relationship between age and global test score, and the effect of perception and comprehension subtest sequence on the global test score. RESULTS Between groups, no significant differences in receptive prosodic abilities were found. Within both groups, the comprehension subtest was significantly more difficult than the perception subtest, and there was a significant negative correlation between age and global test score. No subtest sequence effect could be demonstrated. CONCLUSIONS Considering that the older speakers with hypokinetic dysarthria due to PD had receptive prosodic skills inferior to those of the younger speakers, notwithstanding apparently intact cognition and hearing, the findings suggest that age is a factor to be reckoned with in prosody assessment and management in this population.

Automated Speech Rate Measurement in Dysarthria

PURPOSE In this study, a new algorithm for automated determination of speech rate (SR) in dysarthric speech is evaluated. We investigated how reliably the algorithm calculates the SR of dysarthric speech samples when compared with calculation performed by speech-language pathologists. METHOD The new algorithm was trained and tested using Dutch speech samples of 36 speakers with no history of speech impairment and 40 speakers with mild to moderate dysarthria. We tested the algorithm under various conditions: according to speech task type (sentence reading, passage reading, and storytelling) and algorithm optimization method (speaker group optimization and individual speaker optimization). Correlations between automated and human SR determination were calculated for each condition. RESULTS High correlations between automated and human SR determination were found in the various testing conditions. CONCLUSIONS The new algorithm measures SR in a sufficiently reliable manner. It is currently being integrated in a clinical software tool for assessing and managing prosody in dysarthric speech. Further research is needed to fine-tune the algorithm to severely dysarthric speech, to make the algorithm less sensitive to background noise, and to evaluate how the algorithm deals with syllabic consonants.

The effect of intensive speech rate and intonation therapy on intelligibility in Parkinson's disease

PURPOSE Most studies on treatment of prosody in individuals with dysarthria due to Parkinsons disease are based on intensive treatment of loudness. The present study investigates the effect of intensive treatment of speech rate and intonation on the intelligibility of individuals with dysarthria due to Parkinsons disease. METHODS A one group pretest-posttest design was used to compare intelligibility, speech rate, and intonation before and after treatment. Participants included eleven Dutch-speaking individuals with predominantly moderate dysarthria due to Parkinsons disease, who received five one-hour treatment sessions per week during three weeks. Treatment focused on lowering speech rate and magnifying the phrase final intonation contrast between statements and questions. Intelligibility was perceptually assessed using a standardized sentence intelligibility test. Speech rate was automatically assessed during the sentence intelligibility test as well as during a passage reading task and a storytelling task. Intonation was perceptually assessed using a sentence reading task and a sentence repetition task, and also acoustically analyzed in terms of maximum fundamental frequency. RESULTS After treatment, there was a significant improvement of sentence intelligibility (effect size .83), a significant increase of pause frequency during the passage reading task, a significant improvement of correct listener identification of statements and questions, and a significant increase of the maximum fundamental frequency in the final syllable of questions during both intonation tasks. CONCLUSION The findings suggest that participants were more intelligible and more able to manipulate pause frequency and statement-question intonation after treatment. However, the relationship between the change in intelligibility on the one hand and the changes in speech rate and intonation on the other hand is not yet fully understood. Results are nuanced in the light of the operated research design. LEARNING OUTCOMES The reader will be able to: (1) describe the effect of intensive speech rate and intonation treatment on intelligibility of speakers with dysarthria due to PD, (2) describe the effect of intensive speech rate treatment on rate manipulation by speakers with dysarthria due to PD, and (3) describe the effect of intensive intonation treatment on manipulation of the phrase final intonation contrast between statements and questions by speakers with dysarthria due to PD.