OverviewRumination is an aberrant eating disorder found primarily in infants and individuals with mental retardation. The behavior involves the apparently deliberate regurgitation of food, retainment of the regurgitated food in the mouth, and rechewing or reswallowing the food (Fee & Matson, 1992;Johnston, 1993). Individuals who ruminate appear to do so with no apparent nausea and may gain satisfaction o r pleasure from the act (Humphrey, Mayes, Bider, & Good, 1989; Mayes, Humphrey, Handford, & Mitchell, 1988). Researchers have reported several response topographies associated with the initiation of a rumination sequence: (a) putting a finger into the oral cavity (Luiselli, 1989), (b) thrusting the tongue forward (Luiselli, 1989), ( c ) rocking the body from side to side or arching the back (Franco, Campbell, Tamburrino, & Evans, 1993), and (d) elevating the lower torso higher than the upper torso with sudden forward movements (Johnston, 1993). Episodes of rumination can be brief (e.g., one regurgitation) or may last several hours (Johnston, 1993).Two types of rumination have been described in the literature: psychogenic rumination and self-stimulatory rumination (Mayes et al., 1988). Psychogenic rumination is described as a deliberate, self-satisfying behavior that occurs in otherwise normally developing infants (Franco et al., 1993). Mayes et al. (1988) analyzed 26 infants with psychogenic rumination and found that the mean age of onset was 5.0 months (range = 0.7-17.0 months). In addition, 85% of these infants were functioning within normal developmental limits. Self-stimulatory rumination occurs in individuals with mental retardation, and has an onset ranging from infancy to adulthood (Franco et al., 1993). Mayes et al. (1988) analyzed 40 individuals with self-stimulatory rumination and found that the 564