About CUSP

Behavioral Cusps Anyone?

By Eric W. Maier

Suggestions to use developmental stages as the framework for identifying target behaviors may be presented to behavior analysts by professionals from other fields. These developmental concepts provide behavior change explanations over an individual’s life time as the sequential emergence of different stages (Baer & Rosales-Ruiz, 1997.) Rosales-Ruiz and Baer (1997) discuss how developmental psychologists view the complexity of behavior as organized in a stage progression and describe the increase in behavior by the increasing complexity over an individual’s life time as opposed to the amount behavior increases. Further, the developmental stage is viewed by developmental psychologists as a part of the life of the individual and that each stage is different from other developmental stages in the individual’s life. These developmental stage concepts have been challenged and criticized not only by professionals outside the community of developmental psychologists but by individuals within their own verbal community. Specifically, the vague stage definitions, the developmental explanation of the necessary number of stages, and how the transition from each stage is described have been challenged and criticized (Baer & Rosales-Ruiz, 1997.)

Rosales-Ruiz and Baer (1997) offered a different but comparable concept that can be derived from the most basic mechanisms of behavior analysis, which are its environmental contingencies, and from its most basic strategy, which is to study behavior as its subject matter (Rosales-Ruiz and Baer, 1997, p.1.) This different and comparable concept is the behavioral cusp. 

A cusp is a socially significant behavior change that allows an individual access to new reinforcers, contingencies, and environments that lead to further important behavior changes and that have an impact on the people within the individual’s verbal community (Baer & Rosales-Ruiz, 1997.) To compare developmental stages and behavioral cusps using a metaphoric example, the development or emergence of behavioral stages occurs in a linear format or fashion, whereas with the behavioral cusp it is more like the branches of a tree. They stem from an earlier branch or trunk, and new branches may stem from them, where their structure in conjunction with the environment allows for that. But their mutual order, size, and probability of twigs are not very thoroughly predetermined (Baer & Rosales-Ruiz, 1997.)

Bosch and Fuqua (2001) suggested a set of socially significant behavioral cusp guidelines that may assist behavior analysts and other professionals in identifying appropriate target behaviors when designing programs for individuals with developmental disabilities. Specifically, they proposed that the acquisition of a new behavior:

1. Should allow the learner access to new reinforcers, contingencies, and environments
2. It should be socially valid
3. Generative in that the skill acquired should be a stepping stone to the acquisition of novel behaviors that are not programmed or specifically taught
4. The new behavior is incompatible with an inappropriate behavior or makes a previous behavior obsolete
5. should have an impact on individuals within the learner’s verbal community 

We would further suggest quantifying each of the proposed cusp guidelines which may simplify the identification and assessment of proposed behavioral cusps. The following is an example and is not based on research to date:

1. The new skill allows the learner access to an additional 50% of novel reinforcers, contingencies, and environments from baseline measures
2. It should be socially valid in that 80% of stakeholders agree that the proposed behavior change is socially significant for all parties involved
3. The new behavior should be generative in that the skill acquired should be a stepping stone for the acquisition of a minimum of three novel behaviors that were not programmed or specifically taught. In addition, one of the three novel skills must emerge from a different behavioral domain.
4. The new behavior is incompatible with at least one inappropriate behavior or makes at least one previous behavior obsolete.
5. The behavior change should have an impact on a minimum of 80% of the individuals within the learner’s verbal community. 

The quantification of each proposed cusp guideline may vary from individual to individual and even vary from the individual’s behavioral domains. Future cusp research should investigate whether all five guidelines are necessary when assessing whether or not a behavior change qualifies as a cusp and develop evidence based criteria to quantify each specific cusp guideline. It may also be beneficial if future research could identify whether or not a specific sequential order of the proposed cusp guidelines are necessary in that it would make the process more so efficient when identifying behavioral cusps when designing behavior programs. 

References

Baer, D. M., Wolf, M. M., & Risley, T. R. (1968). Some current dimensions of applied behavior analysis. Journal of Applied Behavior Analysis, 1, 91-97.
Bosch, S., & Fuqua, R.W. (2001). Behavioral cusps: A model for selecting target behaviors. Journal of Applied Behavior Analysis, 34, 123-125.
Bosch, S., & Hixson, M. (2004). The final piece to a complete science of behavior: Behavior development and behavioral cusps. The Behavior Analyst Today, 6, 244-254.