Julien Tardieu

Loudness change in response to dynamic acoustic intensity.

Three experiments investigate psychological, methodological, and domain-specific characteristics of loudness change in response to sounds that continuously increase in intensity (up-ramps), relative to sounds that decrease (down-ramps). Timbre (vowel, violin), layer (monotone, chord), and duration (1.8 s, 3.6 s) were manipulated in Experiment 1. Participants judged global loudness change between pairs of spectrally identical up-ramps and down-ramps. It was hypothesized that loudness change is overestimated in up-ramps, relative to down-ramps, using simple speech and musical stimuli. The hypothesis was supported and the proportion of up-ramp overestimation increased with stimulus duration. Experiment 2 investigated recency and a bias for end-levels by presenting paired dynamic stimuli with equivalent end-levels and steady-state controls. Experiment 3 used single stimulus presentations, removing artifacts associated with paired stimuli. Perceptual overestimation of loudness change is influenced by (1) intensity region of the dynamic stimulus; (2) differences in stimulus end-level; (3) order in which paired items are presented; and (4) duration of each item. When methodological artifacts are controlled, overestimation of loudness change in response to up-ramps remains. The relative influence of cognitive and sensory mechanisms is discussed.

Relationship Between Speech Intelligibility and Speech Comprehension in Babble Noise.

PURPOSEnThe authors investigated the relationship between the intelligibility and comprehension of speech presented in babble noise.nnnMETHODnForty participants listened to French imperative sentences (commands for moving objects) in a multitalker babble background for which intensity was experimentally controlled. Participants were instructed to transcribe what they heard and obey the commands in an interactive environment set up for this purpose. The former test provided intelligibility scores and the latter provided comprehension scores.nnnRESULTSnCollected data revealed a globally weak correlation between intelligibility and comprehension scores (r = .35, p < .001). The discrepancy tended to grow as noise level increased. An analysis of standard deviations showed that variability in comprehension scores increased linearly with noise level, whereas higher variability in intelligibility scores was found for moderate noise level conditions.nnnCONCLUSIONnThese results support the hypothesis that intelligibility scores are poor predictors of listeners comprehension in real communication situations. Intelligibility and comprehension scores appear to provide different insights, the first measure being centered on speech signal transfer and the second on communicative performance. Both theoretical and practical implications for the use of speech intelligibility tests as indicators of speakers performances are discussed.

Sonification of in-vehicle interface reduces gaze movements under dual-task condition

In-car infotainment systems (ICIS) often degrade driving performances since they divert the drivers gaze from the driving scene. Sonification of hierarchical menus (such as those found in most ICIS) is examined in this paper as one possible solution to reduce gaze movements towards the visual display. In a dual-task experiment in the laboratory, 46 participants were requested to prioritize a primary task (a continuous target detection task) and to simultaneously navigate in a realistic mock-up of an ICIS, either sonified or not. Results indicated that sonification significantly increased the time spent looking at the primary task, and significantly decreased the number and the duration of gaze saccades towards the ICIS. In other words, the sonified ICIS could be used nearly exclusively by ear. On the other hand, the reaction times in the primary task were increased in both silent and sonified conditions. This study suggests that sonification of secondary tasks while driving could improve the drivers visual attention of the driving scene.

Expectations in culturally unfamiliar music: influences of proximal and distal cues and timbral characteristics

Listeners musical perception is influenced by cues that can be stored in short-term memory (e.g., within the same musical piece) or long-term memory (e.g., based on ones own musical culture). The present study tested how these cues (referred to as, respectively, proximal and distal cues) influence the perception of music from an unfamiliar culture. Western listeners who were naïve to Gamelan music judged completeness and coherence for newly constructed melodies in the Balinese gamelan tradition. In these melodies, we manipulated the final tone with three possibilities: the original gong tone, an in-scale tone replacement or an out-of-scale tone replacement. We also manipulated the musical timbre employed in Gamelan pieces. We hypothesized that novice listeners are sensitive to out-of-scale changes, but not in-scale changes, and that this might be influenced by the more unfamiliar timbre created by Gamelan “sister” instruments whose harmonics beat with the harmonics of the other instrument, creating a timbrally “shimmering” sound. The results showed: (1) out-of-scale endings were judged less complete than original gong and in-scale endings; (2) for melodies played with “sister” instruments, in-scale endings were judged as less complete than original endings. Furthermore, melodies using the original scale tones were judged more coherent than melodies containing few or multiple tone replacements; melodies played on single instruments were judged more coherent than the same melodies played on sister instruments. Additionally, there is some indication of within-session statistical learning, with expectations for the initially-novel materials developing during the course of the experiment. The data suggest the influence of both distal cues (e.g., previously unfamiliar timbres) and proximal cues (within the same sequence and over the experimental session) on the perception of melodies from other cultural systems based on unfamiliar tunings and scale systems.

Evaluation de la sonifcation d'un système multimédia automobile

An automotive multimedia system that would be sonified should offer to the driver the possibility to interact with this system without his eyes, having thus a better visual focus on the road. The sonification should indeed facilitate the discovery of the system and the navigation within the menu tree.n We have prepared a prototype to test with users the efficiency and acceptability of the sonification, made by hierarchical sounds, vocal synthesis, spearcons (compressed vocal synthesis), musical samples and feeback sounds. Our results confirm that sonification is interesting. Even if it doesnt allow to navigate and to reach the data faster, the participants want to keep it as they find their driving safer.n Vocal synthesis and hierarchical sounds used on the first menu levels are the most helpful sounds with the alphabetical letters used in the long list of data. Hybrid sounds, composed of earcons and auditory icons, are prefered to orchestra sounds (musems) because the link to the fonction is more intuitive. Spearcons are not appreciated because they are not understood and do not help the positioning in the lists of data. Feedback sounds are appreciated all along the navigation, in particular the sound of scrolling and the sound « end of the list / empty list ».

Automatic Speech Recognition Predicts Speech Intelligibility and Comprehension for Listeners With Simulated Age-Related Hearing Loss

PurposenThe purpose of this article is to assess speech processing for listeners with simulated age-related hearing loss (ARHL) and to investigate whether the observed performance can be replicated using an automatic speech recognition (ASR) system. The long-term goal of this research is to develop a system that will assist audiologists/hearing-aid dispensers in the fine-tuning of hearing aids.nnnMethodnSixty young participants with normal hearing listened to speech materials mimicking the perceptual consequences of ARHL at different levels of severity. Two intelligibility tests (repetition of words and sentences) and 1 comprehension test (responding to oral commands by moving virtual objects) were administered. Several language models were developed and used by the ASR system in order to fit human performances.nnnResultsnStrong significant positive correlations were observed between human and ASR scores, with coefficients up to .99. However, the spectral smearing used to simulate losses in frequency selectivity caused larger declines in ASR performance than in human performance.nnnConclusionnBoth intelligibility and comprehension scores for listeners with simulated ARHL are highly correlated with the performances of an ASR-based system. In the future, it needs to be determined if the ASR system is similarly successful in predicting speech processing in noise and by older people with ARHL.

Auditory Information in the Soundscape of a Train Station

This papers issues are (1) to reveal peoples ability to collect information in the soundscape of a train station, and (2) to indicate how this information is involved in the recognition of the different types of space (platform, hall, etc.). In a first study, two listening experiments are carried out on a set of recorded soundscape samples. Three types of acoustical information are revealed by the first experiment: sound sources, human activities, and room effects. The second experiment shows that people were able to recognize the type of space just by listening to its soundscape. Then, the auditory information involved in the space recognition is found by comparing the two experiments. In a second study, an in situ questionnaire survey asked the travellers to describe the soundscape of the space in which they were situated. The results show that the same kind of auditory information is used as those found in the laboratory.

Mechanisms underlying the auditory continuity illusion

This study investigates the auditory continuity illusion, combining psychophysics and magnetoencephalography. Stimuli consisted of amplitude‐modulated (AM) noise interrupted by bursts of louder, unmodulated noise. Subjective judgments confirmed that the AM was perceived as continuous, a case of illusory continuity. Psychophysical measurements showed that the illusory modulation had little effect on the detection of a physical modulation, i.e., the illusory modulation produced no modulation masking. Duration discrimination thresholds for the AM noise segments, however, were elevated by the illusion. A whole‐head magnetoencephalographic system was used to record brain activity when listeners attended passively to the stimuli. The AM noise produced a modulated magnetic activity, the auditory steady‐state response. The illusory modulation did not produce such a response, instead, a possible neural correlate of the illusion was found in transient evoked responses. When the AM was interrupted by silence, oscill...