Remembering the Pre-Aversive Stimulus


There are some terms and concepts from behavioral psychology’s past that have found themselves buried in time. Tucked away in a journal here or there but largely forgotten. The older research that tracked rates of behavior following “noxious stimuli”, for example- A phrase we don’t use anymore.  Time has also changed the fascination with respondent conditioning and effects that just two (or more) paired stimuli somewhere along the line could change responding for a lifetime. Powerful principles, which with progress now seem so mundane. Somewhere in there, we have the pre-aversive stimulus.

The pre-aversive stimulus had a great role in early behavioral science animal research to describe responding patterns, but the concept easily applies to humans as well. A pre-aversive stimulus, simply put, is the stimulus that reliably precedes an aversive stimulus. Have you ever heard the term avoidance responding? Some people may call that “escape-maintained behavior” in the field but it is effectively just that- engaging in behavior (responding) to avoid a stimulus that was aversive in the past. Running away. Getting away. Dodging it. What signals that, then? The pre-aversive stimulus. It goes even further. Just through respondent conditioning, the pre-aversive stimulus can take on features of the aversive stimulus and become a conditioned aversive stimulus itself. Then there’s another pre-aversive stimulus that could reliably precede that, and with enough second-order conditioning, you could get messy (over)generalization and find all sorts of related stimuli as aversive. Generalized Anxiety Disorder theoretically works on this same principle. It’s not hard to see how this kind of thing can tangle up a person’s life- whether they are able to realize it and vocalize it or not.



Wait! Isn’t a pre-aversive stimulus just a kind of SD?

Let’s not jump to any conclusions and mistake a pre-aversive stimulus for an SD just yet. They have some things in common. They’re both stimuli (but so is almost everything else). They can both be considered antecedent stimuli when we look at the framework of the avoidance responding that sometimes follows them. They signal something. All good comparisons- but here’s a big distinction if you don’t remember: A discriminative stimulus (SD) signals reinforcer availability for a specific type of response.

The per-aversive stimulus does not necessarily have to.

In some situations, you could conceptualize a case for negatively reinforced behavior, but that might muddy the definitions of both terms being used concurrently. They speak to different phenomena even though they could describe one particular stimulus. The big difference is that the cue for available reinforcement is not necessary for a pre-aversive stimulus. It is simply a stimulus that has commonly preceded something aversive, or bad.

Example: An individual has been stung by a wasp before. Maybe several times if they were unlucky. Prior to the stinging, they heard the buzzing around a wasp nest.

That buzzing could likely become a pre-aversive stimulus, and through respondent conditioning, a conditioned aversive stimulus itself in the future.

In the research, pre-aversive stimuli tended to evoke “anxiety” in respondents- which was quasi-operationalized to the term conditioned emotional response (CER), also called conditioned suppression. That’s an important distinction to keep in mind. Here, a pre-aversive stimulus appears to suppress or decrease responding- not signal reinforcement for a response like an SD would.

Like freezing near a wasp nest when buzzing is heard. The usual comfortable walking pace (response) is suppressed in the presence of the buzzing sound (pre-aversive antecedent stimulus).



Anxiety! Conditioned Emotional Responses! Conditioned Suppression!

Respondent conditioning research has some fascinating lessons that are just as relevant today as they were decades ago. Sometimes in the day to day practice of behavior analysis- things get oversimplified for the sake of ease of practice.

Behavior goes up? Reinforcement is at work.

Behavior goes down? Punishment is at work.

To a degree, those definitions work. Even with our wasp nest example earlier, those initial stings could absolutely punish some future walking behavior. But we can’t forget about the little things- the little preceding stimuli that have so much to do with the actual phenomenon. The buzzing didn’t punish the walking. Don’t forget the antecedents. Don’t forget the respondent conditioning. Taking the time to examine just one more step explains the process so much more clearly.

What conditioned pre-aversive stimuli appear to evoke conditioned emotional responses in your day to day life? Do you see conditioned suppression of behavior, as a result, that would have otherwise been there? What pre-aversive stimuli could be “tagging on” to the effects of an aversive stimulus you’re aware of? Does it evoke any avoidance behavior?

Too simple? Laurence Miller ‘s (1969) work on compounding pre-aversive stimuli might whet your broader research appetite. Citation below.

Thoughts? Comment! Question! Like!



Coleman, D. A., Hemmes, N. S., & Brown, B. L. (1986). Relative durations of conditioned stimulus and intertrial interval in conditioned suppression. Journal of the Experimental Analysis of Behavior,46(1), 51-66. doi:10.1901/jeab.1986.46-51
Miller, L. (1969). Compounding of pre-aversive stimuli1. Journal of the Experimental Analysis of Behavior,12(2), 293-299. doi:10.1901/jeab.1969.12-293
Ormrod, J. E. (2016). Human learning. Harlow, Essex, England: Pearson.
Image Credits:, photographer Hubert Mousseign

How I Designed An Effective RBT Training Program


When the BACB introduced the Registered Behavior Technician (RBT) credential, I remember reading the email all the way back in 2013 and having my brain race over just how credentialing the entry-level ABA practitioner might work. It was in a sense revolutionary- how many people in psychology or education undergraduate programs would believe that they could work full time in a field related to their study before graduation, and be credentialed for it? I knew that eventually it would be my role to design an effective and efficient RBT training protocol to give the new ABA practitioners a solid education in the basics of ABA and therapy implementation. I started as a therapist myself. I went through the process that eventually lead to my BCBA graduate studies and certification. The question now was, if I were starting all over what would I have wanted to set me up for the greatest chance of success?

The BACB Standards

The RBT Task List and the training guidelines are essential. These are necessary for counting towards the credential. There are certain things you can expound on, and present in variations of practicality, but everyone passing the 40 hour training essentially has to learn the exact same thing as it’s listed by the BACB. Think of this as you would an approved course sequence for BCBA classes. I think it has the best current structure to the material necessary for this level of service, so even if you are thinking of using training that does not necessarily require the RBT credential, this is a great “ABA style” guideline for the necessary skills.

I like to think of it this way: You don’t want to train staff for just the challenges they face right now for clients, you want them to be prepared for all the appropriate behavior-analytic necessities down the line too.

When I designed my first RBT training protocol in 2015, I stuck to the RBT Task List and BACB standards for RBT training to the letter (I still do, but added and improved upon it). My picks for what would be used as the source material to fill out this training were: B.F Skinners collected works, the Baer, Wolf, and Risley article, and my favorite, “Applied Behavior Analysis” by Cooper et al. For my first run at this, I broke it down into modules with discussion board posts, quizzes, and “chapter exams” for each section. While this material was being run, I also preferred to apply these to real-world client situations so that what they saw on the pages could be implemented. Every trainee would meet a real client, see how the material relates, and practice shadowing/running some of the techniques.

Some of the trainings I was seeing online were just Q&A material presentation with quizzes, but no actual practice. That gave me pause because I knew the next step required by the BACB was the competency assessment and that requires actual in vivo clinical skill usage for most sections.

Training to meet the standards of the Competency Assessment and the RBT Exam

My initial 40-hour training program was built from the ground up based on the framework that the BACB set out. It was not until the actual trainee feedback came back from both the competency exams (in clinical skills judged by a BCBA), and the results of the RBT Exam (a Pearson computer testing center exam) that I was able to get the correct amount of information to expand on the areas where most were finding the difficulty. If you’ve taken the BCBA exam, the RBT exam is very similar in style. It’s tough, but has a smaller and more appropriate task list for the job. Multiple choice, but best answer. None of that easy 3 answers are wrong, 1 answer is right. My second training, which I created at the tail end of 2015 and revised twice into 2016 aimed to treat a common difficulty that was arising from my experience with the gaps between the Competency Exam and the RBT Exam. The RBT competency exam was a breeze for people who could use the language and run the data collection, graphing, and skill acquisition skills with clients in the real clinical setting, but when it came to the Pearson exam; using the terms to answer the questions was much tougher. Familiarity with terms was good enough to pass clinical muster, but that RBT Exam was a tough nut to crack.

I adjusted my training to fill this skill gap I was seeing with some of the applicants by testing the terminology during the competency assessment during the option interview section. The BACB has a great sheet they included onto the RBT Competency checklist, which has a series of opened ended topics that the applicant discusses with the testing BCBA. I took those, and adapted some of the tougher relations- People could tell me what frequency data was, but they couldn’t explain what continuous measurement was used for. People could tell me when we used partial and whole intervals, but couldn’t describe why discontinuous measurement was appropriate for a situation. People could use prompting during a discrimination training program, but couldn’t always figure out how to stimulus fade if they saw improvement. Could a 40 hour training really condense all of this down to meet the rigor of the exam? The competency was a breeze for most applicants after the training, but the test required some considerable additional studying if they had never practiced ABA clinical work before. So, I kept going with it, tweaking my training to give some obvious terminology repetition, gain some fluency with the practical in-person time during the 40 hour training. Pass rates went up. Not to 100%, but higher than the first version.


Competency Exam as Feedback

The Competency exam step was really something interesting. It was where we saw the independent clinical skills of the RBT, therapeutically, with real clients, and measurable results. It had interobserver agreement (IOA) built into it. It hit on every topic of the task list, but on the other hand, an applicant could potentially display 1/4 skills and still pass a section which had its own challenges. But we got great feedback from the applicants during the process, how they saw the training, how comfortable and proficient they felt they were, how proficient they actually were.

The competency exam did allow for some limited roleplay where the in-vivo skills were impractical for the situation, but we used those sparingly. The real situations often challenged the applicants in ways that we the observers could not have thought up. There were teachable moments, there were even sometimes failures of the competency, but the next week they were back to try again.

We all learned a lot.

The trouble was that the competency exam was technically separate from the 40 hour training. Someone could come to apply for a position, require a competency exam, but already have a 40-hour certificate from an online training site. More often than not, when it came to skills like discrete trial training (DTT), or other skill acquisition routines that required more than objective maladaptive behavior measurement; these applicants would simply struggle. The prompting techniques were sloppy. “Least to most” was not in their vocabulary. “What is chaining?”– we’d hear. Orientation for the position was not enough, even with a legitimate online 40-hour training. This was also feedback. Was our training process over teaching? Was it too difficult or complex for what the RBT role was designed for? Were we demanding too much from our applicants during the RBT process? If so- how were we to measure that? And how exactly were these materials we were training with, and competency testing with, serving us so well with the applicant results on the RBT Exam through Pearson. Did these outside trainings have the same post-training measures? Did they use feedback? It would be impossible to survey them all. The answers came from somewhere else. The people who actually trained and tested with us the entire way through. Our first year RBTs. They did my training, they passed the competency, they passed the RBT Exam, and they were still working under qualified BCBAs directly in therapy every single day.

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Registered Behavior Technicians as Models in the RBT Training Process

If I were to say one thing that gave the greatest leap in how well we could get new applicants through the process, pass the material, retain the material, and pass both the competency exam (which was a little subjective based on BCBA), and the RBT Exam (which was the be-all objective computer test)- it was the inclusion of practiced Registered Behavior Techs in the 40-hour initial training process itself. They had the viewpoint that a veteran BCBA might not. They went through the most recent RBT Task List updates. They passed their renewal competencies. They knew what these new applicants would have to know not only to pass the competency, but the RBT exam, and prospective employment under a BCBA. They knew it all.  It was late 2017. We had feedback from applicants, we had feedback from post-exam takers, and now we had feedback from the VIP RBTs that were involved in training the new staff.

We had the process down to a well oiled machine. Sometimes we had people slip through the cracks. Sometime we had no calls and no shows. Sometimes people just had test anxiety and had to retake. But the actual practice and feedback from all pieces and perspectives at all levels helped shape it to the form I currently use today. It kept it fresh. I cut out some of the useless parts that didn’t seem to help as well as hands on practice- the discussion board posts. I added more hours into the 40 that were hands on. More terminology usage. More skill transfer checks. Same RBT Task List. Same BACB framework, but with a multi-level feedback and checks and balance system. Everybody had a part to play in the training of the applicants now, and those applicants held on to the things that they would teach to the next applicants that came through once they were RBTs.  Then those RBTs wanted to be BCBAs. Tens. Maybe close to a hundred now.

Three years. Enough time for a graduate program. Enough time for 1500 hours of supervision. Enough time for a BCBA exam cycle. I saw the next generation grow up with ABA right before my eyes.

I love it.


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