Tracking perception of pronunciation variation by tracking looks to printed words: The case of word-final /t/

We investigated perception of words with reduced word-final /t/ using an adapted eyetracking paradigm. Dutch listeners followed spoken instructions to click on printed words which were accompanied on a computer screen by simple shapes (e.g., a circle). Targets were either above or next to their shapes, and the shapes uniquely identified the targets when the spoken forms were ambiguous between words with or without final /t/ (e.g., bult, bump, vs. bul, diploma). Analysis of listeners’ eye-movements revealed, in contrast to earlier results, that listeners use the following segmental context when compensating for /t/-reduction. Reflecting that /t/-reduction is more likely to occur before bilabials, listeners were more likely to look at the /t/-final words if the next word’s first segment was bilabial. This result supports models of speech perception in which prelexical phonological processes use segmental context to modulate word recognition

Acoustic correlates of Dutch lexical stress re-examined: Spectral tilt is not always more reliable than intensity

The present study examined two acoustic cues in the production of lexical stress in Dutch: spectral tilt and overall intensity. Sluijter and Van Heuven (1996) reported that spectral tilt is a more reliable cue to stress than intensity. However, that study included only a small number of talkers (10) and only syllables with the vowels /aː/ and /ɔ/. The present study re-examined this issue in a larger and more variable dataset. We recorded 38 native speakers of Dutch (20 females) producing 744 tokens of Dutch segmentally overlapping words (e.g., VOORnaam vs. voorNAAM, “first name” vs. “respectable”), targeting 10 different vowels, in variable sentence contexts. For each syllable, we measured overall intensity and spectral tilt following Sluijter and Van Heuven (1996). Results from Linear Discriminant Analyses showed that, for the vowel /aː/ alone, spectral tilt showed an advantage over intensity, as evidenced by higher stressed/unstressed syllable classification accuracy scores for spectral tilt. However, when all vowels were included in the analysis, the advantage disappeared. These findings confirm that spectral tilt plays a larger role in signaling stress in Dutch /aː/ but show that, for a larger sample of Dutch vowels, overall intensity and spectral tilt are equally important

At which processing level does extrinsic speaker information influence vowel perception?

The interpretation of vowel sounds depends on perceived characteristics of the speaker (e.g., average first formant (F1) frequency). A vowel between /I/ and /E/ is more likely to be perceived as /I/ if a precursor sentence indicates that the speaker has a relatively high average F1. Behavioral and electrophysiological experiments investigating the locus of this extrinsic vowel normalization are reported. The normalization effect with a categorization task was first replicated. More vowels on an /I/-/E/ continuum followed by a /papu/ context were categorized as /I/ with a high-F1 context than with a low-F1 context. Two experiments then examined this context effect in a 4I-oddity discrimination task. Ambiguous vowels were more difficult to distinguish from the /I/-endpoint if the context /papu/ had a high F1 than if it had a low F1 (and vice versa for discrimination of ambiguous vowels from the /E/-endpoint). Furthermore, between-category discriminations were no easier than within-category discriminations. Together, these results suggest that the normalization mechanism operates largely at an auditory processing level. The MisMatch Negativity (an automatically evoked brain potential) arising from the same stimuli is being measured, to investigate whether extrinsic normalization takes place in the absence of an explicit decision task

Listeners track talker-specific prosody to deal with talker-variability

One of the challenges in speech perception is that listeners must deal with considerable segmental and suprasegmental variability in the acoustic signal due to differences between talkers. Most previous studies have focused on how listeners deal with segmental variability. In this EEG experiment, we investigated whether listeners track talker-specific usage of suprasegmental cues to lexical stress to recognize spoken words correctly. In a three-day training phase, Dutch participants learned to map non-word minimal stress pairs onto different object referents (e.g., USklot meant “lamp”; usKLOT meant “train”). These non-words were produced by two male talkers. Critically, each talker used only one suprasegmental cue to signal stress (e.g., Talker A used only F0 and Talker B only intensity). We expected participants to learn which talker used which cue to signal stress. In the test phase, participants indicated whether spoken sentences including these non-words were correct (“The word for lamp is…”). We found that participants were slower to indicate that a stimulus was correct if the non-word was produced with the unexpected cue (e.g., Talker A using intensity). That is, if in training Talker A used F0 to signal stress, participants experienced a mismatch between predicted and perceived phonological word-forms if, at test, Talker A unexpectedly used intensity to cue stress. In contrast, the N200 amplitude, an event-related potential related to phonological prediction, was not modulated by the cue mismatch. Theoretical implications of these contrasting results are discussed. The behavioral findings illustrate talker-specific prediction of prosodic cues, picked up through perceptual learning during training

Orbital Selective Magnetism in the Spin-Ladder Iron Selenides Ba1−x_{1-x}Kx_{x}Fe2_2Se3_3

Here we show that the 2.80(8) {\mu}B/Fe block antiferromagnetic order of BaFe2Se3 transforms into stripe antiferromagnetic order in KFe2Se3 with a decrease in moment to 2.1(1) {\mu}B/Fe. This reduction is larger than expected from the change in electron count from Ba$^{2+}$ to K$^{+}$, and occurs with the loss of the displacements of Fe atoms from ideal positions in the ladders, as found by neutron pair distribution function analysis. Intermediate compositions remain insulating, and magnetic susceptibility measurements show a suppression of magnetic order and probable formation of a spin-glass. Together, these results imply an orbital-dependent selection of magnetic versus bonded behavior, driven by relative bandwidths and fillings.Comment: Final versio

An introduction to the EULAR–OMERACT rheumatoid arthritis MRI reference image atlas

This article gives a short overview of the development and characteristics of the OMERACT rheumatoid arthritis MRI scoring system (RAMRIS), followed by an introduction to the use of the EULAR–OMERACT rheumatoid arthritis MRI reference image atlas. With this atlas, MRIs of wrist and metacarpophalangeal joints of patients with rheumatoid arthritis can be scored for synovitis, bone oedema, and bone erosion, guided by standard reference images