A phase transition in infants' ability to disengage visual attention

The development of the ability to disengage gaze was followed in 16 infants. Two phases were identified: infrequent disengagement and frequent, flexible disengagement. All infants moved rapidly from the first to the second phase. The infants differed in the age at which the shift began, and in its smoothness. We were unable to conclude definitively that the shift between the two phases was a noncyclic, discontinuous phase transition. There was clear evidence for anomalous variance and tentative evidence for bimodality and inaccessibility. However, whether the rapid change in behaviour was an example of a sudden jump rather than rapid growth was not clear. An experimental investigation to determine if hysteresis is present is recommended.