Habituation and generalization of habituation by nonambulatory, profoundly mentally retarded children

Generalization of habituation along a form dimension was investigated with nonambulatory, profoundly mentally retarded children. On each of 4 testing days, 12 participants (mean CA = 7.83 years, median MA = 3.50 months) were given habituation trials with either a circle or an ellipse, followed by test trials involving presentations of the habituating stimulus and three test stimuli that differed in shape from the habituating stimulus. Fixation times decreased over habituation trials and increased during test trials. No differences in fixation times to test stimuli were found in the group data, and analyses of individual subject data indicated that only 2 children showed generalization gradients.