Brain responses to audiovisual speech mismatch in infants are associated with individual differences in looking behaviour

Research on audiovisual speech integration has reported high levels of individual variability, especially among young infants. In the present study we tested the hypothesis that this variability results from individual differences in the maturation of audiovisual speech processing during infancy. A developmental shift in selective attention to audiovisual speech has been demonstrated between 6 and 9 months with an increase in the time spent looking to articulating mouths as compared to eyes (Lewkowicz & Hansen-Tift. (2012) Proc. Natl Acad. Sci. USA, 109, 1431–1436; Tomalski et al. (2012) Eur. J. Dev. Psychol., 1–14). In the present study we tested whether these changes in behavioural maturational level are associated with differences in brain responses to audiovisual speech across this age range. We measured high-density event-related potentials (ERPs) in response to videos of audiovisually matching and mismatched syllables /ba/ and /ga/, and subsequently examined visual scanning of the same stimuli with eye-tracking. There were no clear age-specific changes in ERPs, but the amplitude of audiovisual mismatch response (AVMMR) to the combination of visual /ba/ and auditory /ga/ was strongly negatively associated with looking time to the mouth in the same condition. These results have significant implications for our understanding of individual differences in neural signatures of audiovisual speech processing in infants, suggesting that they are not strictly related to chronological age but instead associated with the maturation of looking behaviour, and develop at individual rates in the second half of the first year of life.

A Cultural Approach to a Canadian Tragedy: The Indian Residential Schools as a Sacred Enterprise

For over a century, the Canadian state funded a church-run system of residential schools designed to assimilate Aboriginal children into Euro-Canadian culture. In addition to the problems associated with its ethnocentric philosophy, the school system was also characterised by terrible health conditions and physical and sexual abuse of the students was widespread. Recently, the schools have been the object of the most successful struggle for redress in Canadian history. One particularly puzzling aspect about the school system is that it persisted for so long, despite that many of its failings were known very early in its operation. In this article, this puzzle is addressed via a cultural analysis of a political struggle over the residential schools that occurred within Canadian Anglicanism at the outset of the twentieth century. The article concludes that the meaning of the school system as a sacred enterprise contributed to its persistence.