FMRI repetition suppression for voices is modulated by stimulus expectations

According to predictive coding models of sensory processing, stimulus expectations have a profound effect on sensory cortical responses. This was supported by experimental results, showing that fMRI repetition suppression (fMRI RS) for face stimuli is strongly modulated by the probability of stimulus repetitions throughout the visual cortical processing hierarchy. To test whether processing of voices is also affected by stimulus expectations, here we investigated the effect of repetition probability on fMRI RS in voice-selective cortical areas. Changing ('alt') and identical ('rep') voice stimulus pairs were presented to the listeners in blocks, with a varying probability of alt and rep trials across blocks. We found auditory fMRI RS in the nonprimary voice-selective cortical regions, including the bilateral posterior STS, the right anterior STG and the right IFC, as well as in the IPL. Importantly, fMRI RS effects in all of these areas were strongly modulated by the probability of stimulus repetition: auditory fMRI RS was reduced or not present in blocks with low repetition probability. Our results revealed that auditory fMRI RS in higher-level voice-selective cortical regions is modulated by repetition probabilities and thus suggest that in audition, similarly to the visual modality, processing of sensory information is shaped by stimulus expectation processes. © 2012 Elsevier Inc

SpeechDat(E) - Eastern European Telephone Speech Databases

Contains fulltext : 76435.pdf (author's version ) (Open Access)6 p

Audiovisual tools for phonetic and articulatory visu­alitation in computer-aided pronunciation training

Abstract. This paper reviews interactive methods for improving the phonetic competence of subjects in the case of second language learning as well as in the case of speech therapy for subjects suffering from hearing-impairments or articulation disorders. As an example our audiovisual feedback software “Speech-Trainer ” for improving the pronunciation quality of Standard German by visually highlighting acoustics-related and articulation-related sound features will be introduced here. Results from literature on training methods as well as the results concerning our own software indicate that audiovisual tools for phonetic and articulatory visualization are beneficial for computer-aided pronunciation training environments