Infant habituation functions to checkerboard stimuli are dependent on the pattern check-density, age of infant, and temporal dimensions of the stimulus presentations. This study was designed to determine the extent to which these parameters are dependent on the spatial frequency content of the stimuli and the spatial contrast sensitivity of the infant. Data were obtained from 75 2-month-old and 75 3-month-old infants who were presented with either a 4 × 4, 12 × 12, or 20 × 20 achromatic, checkerboard pattern (12 °) for eight trials. Contrast threshold data for 2- and 3-month-old infants were derived from the mean contrast sensitivity function (CSFs) of Banks and Salapatek (1981) and correlated with metrics based on the two-dimensional Fourier amplitude spectrum and both a single-channel filter and multiple-channel filters. In general, the amount of initial fixation, overall fixation, and slopes of the habituation functions were best predicted by a maximum-amplitude model. These findings are discussed in terms of a dual-process theory of infant visual attention in which stimuli with greater suprathreshold energy, as seen through the infant's CSF, potentiate visual fixation via a sensitization pathway.
- spatial frequency
ASJC Scopus subject areas
- Developmental and Educational Psychology