Pica, or the ingestion of inedible items, is a constant risk for some members of the developmentally disabled population. Within this population, two subsets of patients engaging in pica behaviors is evident: The severely to profoundly mentally retarded (lower functioning individuals), and the mildly to severely retarded with a co-occurring psychiatric diagnosis (higher functioning individuals).   This essay will present this writer’s personal observations of pica behavior during the course of 3+ years observing inpatient populations with developmental challenges. However, this writer has not employed formal research methodology to validate the hypotheses here to be offered.

Among the lower functioning and the higher functioning inpatient populations, the function of the pica behavior and how they engage in the pica act may appear similar if such variables are generalized, but when carefully observed, the function of the behavior and how they engage in the pica act is what truly differentiates these two populations. The pica act is self-reinforcing for both populations, but for different reasons. Likewise, the behavioral and situational antecedents prior to engaging in pica behaviors evidenced in lower functioning individuals vs. higher functioning individuals include similar factors, but also include specific dissimilar factors.

Lower functioning individuals engage in pica behavior as if they were in a developmental phase that failed to reach appropriate developmental milestones. They usually have a “preferred” nonedible item and will impulsively gravitate to that particular item. The lower functioning individual seems to be in a primitive, developmentally arrested stage of development, focusing on his or her pica need, the pica item, and the likely reinforcement that the pica item provides. That is a feedback loop, but apparently without connection between complex cognitions, brain executive functioning, planning, and the pica act.  For example, some lower functioning individuals will scan their environment for cigarette butts, and will abruptly run towards such item, with no or little regard for their safety (they may see a cigarette butt in the middle of a busy intersection, and will likely try to pick it up). No complex cognitions seem to be at play, neither higher executive decision making or planning. Impulse control, or the lack of, seems to play an important role in relation to their behavior.

Higher functioning individuals, on the other hand, demonstrate more complex behaviors and demonstrate other needs associated with the pica act. Higher functioning individuals, similar to the lower functioning individuals, have preferred pica items, although the pica behavior is sometimes exhibited during opportunistic situations, and during such opportunistic times the pica item chosen may be different than the “preferred” one. Opportunistic situations may include those situations in which the pica items are available and there are no staff monitoring the individual, or when the individual’s emotions are in turmoil and upheaval and the pica items are at hand’s reach, or a combination of several additional factors. During pica incidents it appears that the drive towards preferred pica items is significantly less prominent among the higher functioning individuals, other than the composition of the item, which usually tends to contain metals in one shape or another. Furthermore, for the higher functioning individuals, nonedible items include more man-made objects as compared to the lower functioning individuals (batteries, clips, thumbtacks, rings, pendants, earrings, etc.).  Moreover, a key difference in the pica behaviors evidenced between the two groups is that the higher functioning individuals will generally let someone know they have just ingested a nonedible item, and this is a key marker. The higher functioning individuals want staff to know about their pica act and want staff to know about the specific nonedible item ingested.

This is an important difference because with the higher functioning individuals the pica act seems to involve a three-way feedback loop. The higher functioning individual, by telling staff about his or her pica consumption, brings an additional variable to the function of the behavior. In addition, the higher functioning individuals appear to engage in elaborate pica rituals which involves the planning stage (of course, sometimes it is an impulse control event that is not planned), the physical act of grabbing the pica object and hiding it for later use - or using it right away; the telling staff about the actual pica act and what type of nonedible object was ingested, and the follow up response by staff. (Yes, the response by staff following a pica incident seems to be a part of the patient’s pica ritual). Thus, the relevance of their pica behavior is likely mediated by intrinsic self-reinforcing factors and also by extrinsic but reinforcing factors.

If these hypotheses are correct, then interventions must be individualized and tailored to the specific needs of each individual in order for the clinical interventions to be successful. For example, trying to extinguish a pica behavior exhibited by a lower functioning individual using complex behavioral/cognitive approaches is unlikely to succeed, as his/her pica behavior appears to be driven by rather primitive needs probably due to the result of developmentally-arrested key developmental milestones. On the other hand, utilizing a rather simple approach to attempt to extinguish a complex pica behavior evidenced in a higher functioning individual diagnosed with a co-occurring psychiatric disorder is unlikely to succeed, as well. To complicate matters, staff interventions aimed at reducing the pica incidents may inadvertently reinforce the pica behavior on both the lower functioning individuals and the higher functioning individuals.

Staff interventions may actually become a positively reinforcing event for the higher functioning individual if not handled properly by inadvertently positively reinforcing the pica ritual. For the lower functioning individual, interventions by staff may inadvertently create an intermittent schedule of reinforcement. Staff interventions may involve a negatively punishing event for the lower functioning individual, in which staff remove from the individual the desired pica item and ensures no other preferred pica items are within their reach. If no formal and informal training for the extinction of the pica behavior is employed, including the lack of a clear plan that addresses the acquisition of positively alternate behaviors, interventions are likely to fail, because rather than replacing a maladaptive behavior with an alternate positive replacement behavior, staff may be unknowingly reinforcing the craving for the pica item. Consider the following probable case scenario: 1) The lower functioning individual and his/her environment are not monitored properly and he/she is not provided with a clear positive replacement behavior plan and an individualized strategy tailored to his or her needs.  2) The individual intermittently finds the desired pica item and ingests it. 3) The intermittently finding and ingesting the pica item likely reinforces a stronger drive toward the pica item. 4) A difficult-to-extinguish intermittent schedule of reinforcement toward the pica item is then created and maintained.

In summary, pica behavior is a complex issue.  Whereas in the case of the lower functioning individuals the pica act may satisfy developmentally primitive needs, on the higher functioning individuals the pica ritual and the pica act may also include more elaborate self-reinforcing needs. Additionally, environmental factors including staff interventions may play key roles in the continuation of the pica behavior for both populations.  Thus, pica reduction strategies must be tailored to the specific needs of the individual engaging in pica. Additionally, proper staff training needs to be emphasized, because poorly trained staff may inadvertently create an environment in which the pica act is reinforced, rather than extinguished. To conclude, although this essay was based on careful observations of adults with developmental disabilities who engage in pica behaviors and living in inpatient settings, formal research methodology needs to be implemented to validate – or invalidate – the above-mentioned hypotheses.

Written by Julio Reyna, Psy.D.