This research examined the effects of relative degree of exposure (a possible establishing operation) to potential reinforcers that were non-edible (i.e., toys) on the preferences of four children who have a developmental disability. The children, ranged from eight to twelve years of age and the experiment was conducted in each of their homes after school. Parents helped select six toys that were small and easily handled for each child and that they thought the child enjoyed. The children had access the toys only in the experimental sessions. Multiple stimulus without replacement (MSWO) preference assessments were conducted with each child to identify a preference ranking for each toy. The four bottom ranking toys were used in alternating control and test sessions. In the control sessions, participants were given 5 min of free access to each of the four toys prior to a MSWO preference assessment in each session. In the first eight test sessions, called deprivation sessions, the participants were given 5 min of free access to all but their lowest preferred toy before the MSWO assessment. The four highest ranked of the six toys were used for the second series of control and test sessions. Control sessions continued as before using these highest ranked toys. In the eight test sessions, called habituation sessions, participants were given 5 min of free access to only the most preferred toy. There were no consistent effects on preferences for the toys in the deprivation sessions, whereas the most preferred toy was selected less often in the in the habituation sessions. These results suggest that prior exposure to toys reduces the value of the toys
