Inhibition of return in very young infants: A longitudinal study

Inhibition of return (IOR) was measured at 2-week intervals from 6 weeks to 6 months of age in 16 infants. IOR refers to the tendency not to return attention to a recently attended location. A spatial cueing task adapted to the attentional and oculomotor skills of the youngest infants was used. At 6 weeks, infants looked more frequently and faster to cued targets. Looks to uncued targets were more frequent than looks to cued targets from 16 weeks, and faster than looks to cued targets from 18 weeks. Infants differed in the tempo of development and the level of performance on both indices of IOR in the final session, individual preferences for uncued targets fluctuated from session to session, Unstable looking biases were observed in all infants. They explained a significant part of the intra-individual differences in preference. Latency to look to uncued targets was stable from the 18-week session.