Comparison of blocking strategies informed by precursor assessment to decrease pica
Block the first small precursor movement instead of waiting for the full pica attempt.
01Research in Context
What this study did
The team worked with four people who kept eating non-food items. The behavior seemed to happen for its own sensory payoff.
First they watched for tiny early moves that came right before pica. Then they tried two blocks: one that stopped the early move, and one that waited for the actual pica. They counted which block cut the eating more.
What they found
Stopping the early move worked as well or better for three of the four people. Waiting for the full pica did not give better results.
When they blocked the first small move, pica dropped and stayed low. The early-move block was easier and safer for staff.
How this fits with other research
Heath et al. (2019) showed you can run a safe functional analysis on early moves instead of the dangerous act. Rettig et al. put that idea into action by blocking those same early moves.
Borlase et al. (2017) and Schmidt et al. (2020) also proved that early moves share the same cause as the big problem. Rettig’s team used that proof to pick the exact move to block, linking good assessment to quick treatment.
Williams et al. (2005) used blocking to teach colors, not to stop danger. The word “blocking” sounds the same, but the goals differ—one teaches, one protects.
Why it matters
If a client eats items for automatic sensory input, watch for the first tiny reach or hand flick. Block that early move instead of waiting for the mouth contact. You will likely see fewer pica tries and keep everyone safer.
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02At a glance
03Original abstract
Pica is dangerous behavior and often maintained by automatic reinforcement. We conducted a latency functional analysis (FA) using safe consumption items to verify that pica was maintained in part by automatic reinforcement and exclude participants for whom pica was likely maintained solely by attention. Next, we identified precursors to pica through a probability analysis and conducted a brief blocking assessment for participants' whose pica occurred in the alone and attention conditions of the FA. Finally, we compared blocking precursors with pica, touching an inedible item and the pica itself. Results showed that five of the six participants' pica was likely maintained by automatic reinforcement, and pica decreased during the brief blocking assessment for three of four participants. Results of the blocking comparison showed that blocking behaviors earlier in the response hierarchy was as effective as only blocking pica attempts for two participants and more effective for one participant.
Behavioral Interventions, 2019 · doi:10.1002/bin.1660