Visual speech inputs can enhance auditory speech information, particularly in noisy or degraded conditions. The natural statistics of audiovisual speech highlight the temporal correspondence between visual and auditory prosody, with lip, jaw, cheek and head movements conveying information about the speech envelope. Low-frequency spatial and…

In this study, we investigated how people deal with irrelevant contextual information during speech production. Two main models have been proposed. WEAVER++ assumes that irrelevant information is removed from the production system by an early blocking mechanism. On the other hand, the response exclusion hypothesis assumes a blocking mechanism that…

This fMRI study was conducted to investigate whether language semantics is processed even when attention is not explicitly directed to word meanings. In the "unattended" condition, the subjects performed a visual detection task while hearing semantically related and unrelated word pairs. In the "phoneme" condition, the subjects made phoneme…

Conversation is multi-modal, involving both talk and gesture. Does understanding depictive gestures engage processes similar to those recruited in the comprehension of drawings or photographs? Event-related brain potentials (ERPs) were recorded from neurotypical adults as they viewed spontaneously produced depictive gestures preceded by congruent…

Everyday conversation is both an auditory and a visual phenomenon. While visual speech information enhances comprehension for the listener, evidence suggests that the ability to benefit from this information improves with development. A number of brain regions have been implicated in audiovisual speech comprehension, but the extent to which the…

Broca's area has been considered, for over a century, as the brain centre responsible for speech production. Modern neuroimaging and neuropsychological evidence have suggested a wider functional role is played by this area. In addition to the evidence that it is involved in syntactical analysis, mathematical calculation and music processing, it…

Speech is not a purely auditory signal. From around 2 months of age, infants are able to correctly match the vowel they hear with the appropriate articulating face. However, there is no behavioral evidence of integrated audiovisual perception until 4 months of age, at the earliest, when an illusory percept can be created by the fusion of the…

Variability in talker identity, one type of indexical variation, has demonstrable effects on the speed and accuracy of spoken word recognition. Furthermore, neuropsychological evidence suggests that indexical and linguistic information may be represented and processed differently in the 2 cerebral hemispheres, and is consistent with findings from…

Many studies have shown that infants prefer infant-directed (ID) speech to adult-directed (AD) speech. ID speech functions to aid language learning, obtain and/or maintain an infant's attention, and create emotional communication between the infant and caregiver. We examined psychophysiological responses to ID speech that varied in affective…