preferential looking

A method used to assess visual acuity in pre-verbal infants and young children. It involves presenting two side-by-side stimuli: one with black and white stripes (gratings) of varying spatial frequencies, and the other a homogeneous gray field matched for luminance. An observer judges which stimulus the infant preferentially looks at by monitoring their eye and head movements. The finest grating the infant can resolve provides an estimate of their visual acuity.