Patterns of jaw coarticulatory direction and linguomandibular coordination in VCV sequences

Data on lingual movement, dorsopalatal contact and F2 frequency presented in previous papers of ours (Recasens, 2002; Recasens and Pallarès, 2001; Recasens, Pallarès and Fontdevila, 1997) suggest that the degree of articulatory constraint (DAC) model accounts to a large extent for the extent and direction of tongue dorsum coarticulation in VCV and CC sequences. A goal of this investigation is to verify the predictions of this model with respect to jaw V-to-V effects in VCV sequences using articulatory movement data collected with electromagnetic articulometry (EMA)

Test-retest reliability of the magnetic mismatch negativity response to sound duration and omission deviants

Mismatch negativity (MMN) is a neurophysiological measure of auditory novelty detection that could serve as a translational biomarker of psychiatric disorders, such as schizophrenia. However, the replicability of its magnetoencephalographic (MEG) counterpart (MMNm) has been insufficiently addressed. In the current study, test-retest reliability of the MMNm response to both duration and omission deviants was evaluated over two MEG sessions in 16 healthy adults. MMNm amplitudes and latencies were obtained at both sensor- and source-level using a cortically-constrained minimum-norm approach. Intraclass correlations (ICC) were derived to assess stability of MEG responses over time. In addition, signal-to-noise ratios (SNR) and within-subject statistics were obtained in order to determine MMNm detectability in individual participants. ICC revealed robust values at both sensor- and source-level for both duration and omission MMNm amplitudes (ICC = 0.81-0.90), in particular in the right hemisphere, while moderate to strong values were obtained for duration MMNm and omission MMNm peak latencies (ICC = 0.74-0.88). Duration MMNm was robustly identified in individual participants with high SNR, whereas omission MMNm responses were only observed in half of the participants. Our data indicate that MMNm to unexpected duration changes and omitted sounds are highly reproducible, providing support for the use of MEG-parameters in basic and clinical research

Lower Approximations by Fuzzy Consequence Operators

Peer ReviewedPostprint (author's final draft

Acoustic characteristics of velar stops and velar softening in German, Polish and Catalan

Two hypotheses have been proposed in order to account for velar softening, i.e., a process through which /k/ changes to an affricate. Whereas one hypothesis states that for the process to apply the velar stop has to be realized as an (alveolo) palatal stop (articulation-based hypothesis), the other claims that velar softening is triggered by acoustic similarity between the input and output segments (acoustic equivalence hypothesis). The present paper investigates the acoustic equivalence hypothesis by comparing several acoustic properties of /k/ in various vowel contexts with those of /ts , ts , tc / for three languages differing in stop burst aspiration, i.e., German, Polish and Catalan. Results suggest that the acoustic equivalence hypothesis could account for velar softening in aspirated velar stops but not in unaspirated velar stops. The results also provide an explanation as to why aspirated velar stops are prone to undergo softening more easily when followed by front vocalic segments than in other contexts and position

Low-frequency oscillatory correlates of auditory predictive processing in cortical-subcortical networks: a MEG-study

Emerging evidence supports the role of neural oscillations as a mechanism for predictive information processing across large-scale networks. However, the oscillatory signatures underlying auditory mismatch detection and information flow between brain regions remain unclear. To address this issue, we examined the contribution of oscillatory activity at theta/alpha-bands (4–8/8–13 Hz) and assessed directed connectivity in magnetoencephalographic data while 17 human participants were presented with sound sequences containing predictable repetitions and order manipulations that elicited prediction-error responses. We characterized the spectro-temporal properties of neural generators using a minimum-norm approach and assessed directed connectivity using Granger Causality analysis. Mismatching sequences elicited increased theta power and phase-locking in auditory, hippocampal and prefrontal cortices, suggesting that theta-band oscillations underlie prediction-error generation in cortical-subcortical networks. Furthermore, enhanced feedforward theta/alpha-band connectivity was observed in auditory-prefrontal networks during mismatching sequences, while increased feedback connectivity in the alpha-band was observed between hippocampus and auditory regions during predictable sounds. Our findings highlight the involvement of hippocampal theta/alpha-band oscillations towards auditory prediction-error generation and suggest a spectral dissociation between inter-areal feedforward vs. feedback signalling, thus providing novel insights into the oscillatory mechanisms underlying auditory predictive processing

Coarticulació i assimilació en fonologia : dades de moviment lingual sobre els grups consonàntics amb C2=/d/ en català

This paper uses the electromagnetic midsagittal articulometry technique (EMMA) for the investigation of tongue tip and tongue blade activity during the production of Catalan clusters consisting of consonants specified for adjacent places of articulation. C2 of these clusters is /d/ (a dental in Catalan); C1 is either an alveolar (/1/, /n/, /r/, /z/), a post-alveolar (/ʒ/) or an alveopalatal (/ʎ/). Apical and laminal trajectories for these clusters are compared to those for intervocalic /d/ and for intervocalic C 1. Data show the presence of a single dental articulation for /nd/ and /1d/ and of two sequential articulatory places (alveolar for Cl and dental for C2) in the case of the cluster /rd/. The clusters /zd/ and /ʒd/ are produced with an alveolar place followed by an intermediate place between the dental and the alveolar zone, which indicates progressive co-articulatory effects (or even progressive assimilation) from Cl fricative onto C2=/d/. Finally, the production of the sequence /ʎd/ involves presumably gestural blending resulting into an intermediate location between that for C1 and that for C2. The notion of «articulatory constraint» is discussed in the light of these results