This study explores vocal development as an early marker of autism, focusing on canonical babbling rate and onset, typically established by 7 months. Previous reports suggested delayed or reduced canonical babbling in infants later diagnosed with autism, but the story may be complicated. We present a prospective study on 44 infants later diagnosed…

Fragmented sleep is common in infancy. Although night awakening is known to decrease with age, in some infants night awakening is more persistent and continues into older ages. However, the influence of fragmented sleep on development is poorly known. In the present study, the longitudinal relationship between fragmented sleep and psychomotor…

Saccade latency is widely used across infant psychology to investigate infants' understanding of events. Interpreting particular latency values requires knowledge of standard saccadic RTs, but there is no consensus as to typical values. This study provides standard estimates of infants' (n = 194, ages 9 to 15 months) saccadic RTs under a range of…

Screening studies of a population in primary health care are sparsely reported. The aim was to describe observed atypical behaviours that may be associated with autism spectrum conditions, in a population (n?=?4,329) of infants at eight months. Observations were performed by paediatric nurses. An observational instrument, named SEEK developed for…

Infants can track small groups of solid objects, and infants can respond when these quantities change. But earlier work is equivocal about whether infants can track continuous substances, such as piles of sand. Experiment 1 ("N" = 88) used a habituation paradigm to show infants can register changes in the size of piles of sand that they…

Background: The present study was designed to investigate the association between visual exploratory behaviour in early infancy, novelty seeking in adolescence, and the dopamine D4 receptor (DRD4) genotype. Methods: Visual attention was measured in 232 three-month-old infants (114 males, 118 females) from a prospective longitudinal study using a…