Infant side biases and familiarity-novelty preferences during a serial paired-comparison task

We monitored changes in looking that emerged when 3- to 6-month-old infants were presented with 48 trials pairing familiar and novel faces. Graphic displays were used to identify changes in looking throughout the task. Many infants exhibited strong side biases produced by infants looking repeatedly in the same direction. Although an overall novelty preference was found for the group, individual infants exhibited brief novelty runs. Few infants began with a familiarity preference. We argue that variable looking patterns emerged during the task from competition between the infants' preference to look for something novel versus their tendency to look back to previous locations. Our data suggest that looking during paired-comparison tasks is a dynamic process dependent on perceptual-motor events happening during the task itself.