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Learning the Functional Analysis- Bryan's first FA of Challenging Behavior

blog post Dec 29, 2022
Behavior analysis talking about learning the functional analysis

Disclaimer: All persons and the company described herein are fictional. Any resemblance to humans or companies, real or fake, is coincidental and unintentional. 


Byan’s First Functional Analysis of Challenging Behavior (Part 2) 

Bryan’s breath makes a cloud on the two-way mirror that looks into Ideal World Behavioral Solution (IWBS)’s assessment room. The coolness of the room punctuates the starkness of floor-to-ceiling padding and child-sized furnishings. Rose, one of the behavioral technicians at IWBS, is perched atop a comically tiny chair, pretending to read an adult-size edition of Highlights magazine. Between page flips, she imperceptibly glances at Mateo, a 5-year-old learner who started therapy at IWBS last week, to check that he is safe. Mateo is not only safe but happily arranging cards from an animal matching game in a neat, domino-like line around  Rose’s feet. Bryan smiles at the intricacy of Mateo’s design and makes a mental note that the kid has got some serious concentration and independent play skills.   

During the intake interview that Bryan conducted two weeks ago, Mateo’s parents said they were most concerned about his recent bouts of aggression towards his peers and his sister, which seemed to start around the same time Mateo started public school and his father picked up night shifts. Watching Mateo now, as he gingerly places the cards around the perimeter of Rose’s chair, one would never guess that, last night, he pulled a lock of his sister’s hair out by the roots or that, weeks ago, he hit a peer at school that resulted in a week’s suspension.


Though not apparent on her intentionally expressionless face, Rose is thrilled for the opportunity to be a therapist in a functional analysis (FA). She read about FAs in her Introduction to Applied Behavior Analysis (ABA) course last semester, but she has yet to be a part of one. Though she would rather be playing with Mateo (his interest in animals allows for plenty of teaching opportunities), she realizes that this FA is a necessary and temporary prelude to designing a behavioral treatment for challenging behavior. She knows that the results of the “unnatural-looking” sessions they do this week will allow Bryan to design a reinforcement-based treatment for Mateo’s aggression—and that treatment will be focused on teaching Mateo a different, less harmful way of communicating whatever it is that his aggression is currently communicating. 

In addition to feeling excited for the FA, Rose is also feeling grateful to work with Bryan, her new supervising BCBA®. She gained a lot of respect for Bryan last week during a team meeting, when he admitted to having no experience with FA. While listening to Bryan explain his plan, which included having Jessica, a more senior BCBA® advise and assist with an FA of Mateo’s aggression, Rose intuited that it is a rare and splendid thing to have a supervisor who readily admits their limitations and takes their supervisees on learning journeys with them. 

During the team meeting that bolstered Rose’s respect for Bryan, Bryan and Jessica reviewed the data collected on Mateo’s aggression thus far (from parent interviews and technician-collected ABC data), discussed their plan for the FA, and conducted behavioral skills training (BST) for the 3 technicians who would be therapists and data collectors during the FA. At first, Rose thought all of that training was overkill, but, after talking with some folks in her master’s cohort, she realized how special her work experience truly is—and what excellent learning opportunities she fell into. 

Rose checks that her attention scripts are still tucked in the magazine—textual prompts in case she needs them. Yes, still there; good. She skims the page: “That hurts,” “Oh no, I don’t like when you do that,” and “I’m going to tell your father,” are among the phrases listed. 

She wonders what other forms of attention Mateo’s sister, peers, and parents typically provide after he has done something aggressive to them. She ponders the many dimensions “attention” can have: the words that could be used, how long each instance could last, the combinations of physical touch that could co-occur…. His sister might cry, Rose imagines, or his mom might say “that’s not a nice thing to do,” and give him something else to do, away from his sister. It is almost as if Rose, having children of her own, read the interview Bryan conducted with Mateo’s mother earlier this week. 


Bryan’s finger is hovering over the “AGG” button on his electronic data collection app, as he waits for any form of aggression to occur. Before starting the session, he reread the operational definitions, like he usually does before collecting data:

Aggression is defined as any instance of unrequested, forceful contact between Mateo’s hands, feet, or teeth and another person.

Clear, concise, and complete, he thought at the time. But, now, as he waits for aggression to occur, he thinks it could be clearer. He regrets his use of the word “forceful.” How will I know if the contact is “forceful,” and would another observer agree?, he asks himself. I’ll refine the definition later, he reasons, as he silently wipes the fog from the mirror with his sleeve. 

Bryan glances at his timer and feels his anticipation grow. It is 4 minutes into the first 5-min session of the functional analysis (FA) that he and Jessica designed, but Mateo has yet to do anything besides play contentedly on the floor. Bryan wonders whether he should remove the matching game: It was the lowest-preferred item in the Paired-Stimulus Preference Assessment (PSPA) they conducted earlier in the week, as a preparation for the FA, but it seems to be distracting Mateo from any desire he might have to play with Rose. 

He knows that Jessica said that moderate-to-low preferred items are sometimes included in the attention condition of an FA to decrease the likelihood that there will be a false-positive if the challenging behavior is automatically maintained. But, considering the target is aggression, which is rarely automatically maintained, he wonders if they can remove the game now that they’ve started the assessment. 

He remembers how Jessica warned him that, despite their careful planning, safety preparations, and staff training, it was possible that they might not see any challenging behavior, in which case they can go back to the interview or observational data to see if there is something they’re missing. 

I wonder what I can do to make aggression more likely now so I can make it less likely later, Bryan wonders. The faster they can identify the function of Mateo’s aggression, the faster they can design a function-based treatment (i.e., a reinforcement-based treatment likely to be effective without punitive methods). 


Rose hears a timer beep: her cue that the session is over. She tells Mateo that she has to leave and Bryan is coming in with some new toys. Upon standing, Rose loses her balance; she stumbles backward into her chair, scattering Mateo’s carefully arranged line of cards across the floor beside him. 

Mateo, who is still on the floor, shrieks and grabs for Rose’s legs. He screams as he hits her, but she steps back and blocks her legs with a safety pad. Rose learned during last week’s training that, even if the session ends, she is to continue doing what she was doing in the session, including blocking and safety procedures. So, she backs up to avoid Mateo’s kicks and says, “Please don’t kick me, Mateo. I don’t like when you kick me.”  

Mateo has fallen to the floor; he is crying and kicking blindly into the air. Though still blocking her legs with the pad, one of his kicks lands on her shin. She winces. Considering her limited experience with challenging behavior, she surprises herself with how quickly she thinks on her feet. 

Jessica told her to improvise the attention statements when needed, so she abandons the scripted lines for the more natural, “I’m so sorry, Mateo. I didn’t mean to kick your cards. I would be upset if that happened to me, after working so hard to build it. Do you want me to put it back together?”  


Bryan enters. He gestures to Rose to check that Mateo is OK. Rose nods and gives a thumbs up to say, I’ve got this. Mateo’s face is covered by his hands, but he probably saw the gesture. Mateo continues to cry, but he is no longer kicking. 

Bryan feels nervous. He is supposed to be in charge, but this was unplanned, and he doesn’t know what to do! He knows Jessica is watching and feels the pressure build in his chest. 

In a moment of clarity, he realizes they did plan for this. Well, not this, exactly, but the protocol he and Jessica wrote states that, if challenging behavior occurs at the end of or between FA sessions, he would step in as therapist and attempt to de-escalate the challenging behavior. So, they had a plan for him to de-escalate the situation, but now he is not sure what de-escalate entails. Nothing like finding the holes in your plan through experience! 

Bryan gestures to Rose that he will take over; she passes the safety pad to him as she leaves. Bryan sits beside Mateo while his sobs subside; eventually, Bryan asks if he would like to play with the cards or something else. Mateo doesn’t reach for the cards, so Bryan looks to the window and raises his eyebrows, hoping that Jessica is still there to pick up on his silent mand for materials. 


Jessica, who walked up just before Bryan entered the room, has been observing from behind the mirror. Rose debriefed her when she exited, and Jessica was not surprised to learn that aggression occurred when Mateo’s cards were knocked out of place. His mother reported something similar with other lined-up items at home, especially when his sister was involved. The consequences are the most relevant information, though, and she cannot get a clear handle on what the relevant consequences entail, from the interview or this single observation. 

Jessica sees Bryan look towards the glass. She interprets his look to mean that, now that  Mateo has been calm for a few minutes, he will continue on with the FA. It is fortuitous that the next FA condition is a control condition, in which Mateo will have free access to his highest preferred activities and plenty of attention. Jessica locates the bin marked “control items” and brings it into the session room with Bryan and Mateo. 


Mateo’s eyes light up upon seeing an iPad, his most preferred item, in the bin. As soon as he reaches for it, nothing else matters. For the next 5 min, Mateo does not look up from his iPad; yet, Bryan sits beside him, intermittently making comments about the images on the screen. 

Some control condition this is, Bryan thinks to himself. The last 10 minutes have been a bust! He is really starting to get down on himself and the whole FA process. This is just too structured. Naturally occurring situations are messier than this. Why would he engage in aggression in order to get attention while he’s doing something by himself? Social-positive and social-negative reinforcement…it’s impossible to isolate them so cleanly! He wonders, What was it about the cards being strewn that evoked aggression towards Rose? Was the relevant EO deprivation, aversive stimulation, or…frustration? He knows frustration is not a function of behavior, at least not one that he was taught, but he can relate to feeling so frustrated that it makes him sometimes want to do something. 

Maybe there’s something about the feeling of frustration that is an EO for aggression, he thinks. But why? What reinforcers occur, besides a decrease in the feeling of frustration? He is certainly feeling a little frustrated now, attempting to describe the function of Mateo’s aggression using 4-term contingency social-positive and social-negative reinforcement terminology. He cannot state it cleanly. Did aggression provide some escape from the feelings of frustration or disappointment? He needs to talk to Jessica before he spins his gears into the more familiar territory of explanatory fictions, mentalisms, and hypothetical constructs. 

He hears the timer beep and tells Mateo, “Two more minutes with the iPad, then it will be time to get ready for lunch.” This last bit was not part of the FA protocol, but Bryan made an executive decision to buy himself some time while he talks to Jessica. In 10 short minutes, Bryan has felt excitement, anticipation, curiosity, fear, ease, and frustration; perhaps understandably, 10 min was enough time for his FA enthusiasm to wane. 

Tim, another of the technicians participating in the FA, enters the room so Bryan can leave. Thank goodness Jessica is here to help coordinate, Bryan thinks. He will be sure to bring her a coffee later. Bryan says to Tim, “just continue doing what I was doing; don’t start the next session yet.” 


When Bryan enters the hallway, he sees that Jessica has placed a few stools against the wall with the two-way mirror. Jessica is seated on the middle stool, with Rose beside her. Rose has the data collection software ready for action, but Bryan tells her to hold off for a minute. Rose, now having nothing to do, starts disinfecting the matching game and other session materials. 

“This isn’t going well, Jess,” Bryan states, as he sits on the stool closest to the door. 

“What makes you say that?” Jessica asks. “We finally saw aggression at the clinic. It is of great concern to his parents; it occurs at home and school but, until a few minutes ago, had yet to occur here. We have to see behavior in order to treat it; now that we have, we can figure out when it’s more and less likely to occur in order to design an effective, non-punitive treatment. So what if aggression didn’t happen during the session? One bout wouldn’t be enough to make conclusions anyway. Now we know at least one circumstance under which it is likely to occur!” 

Bryan begrudgingly agrees. “Yeah, but I don’t know how to explain the potential function in terms of 4-term contingencies.” 

Yet!” Jessica emphasizes the word, “We don’t know how to explain it yet.” Her enthusiasm is catching. “Look, we only have two data points. Both are zero, but we saw aggression once. Let’s not scrap the FA process. Let’s rethink our plan based on new evidence and lack thereof. Remember, an FA is never set in stone. ‘Towards a functional analysis…’” she says, making air quotes. “What are your main concerns?” 

“I guess my main concern is that the only antecedent to aggression that we’ve seen is someone messing up the cards Mateo spent 5 minutes arranging – that’s not an EO I want to test repeatedly.” 

“OK, fair enough,” Jessica adds. “Messing up the hard work of children…not part of the job.” She pauses a beat, then ticks the options off on her fingers. “We can go back to the interview and look for other antecedents. We can talk to his mother again, to add to the existing interview. We can conduct a few probes of similar antecedent conditions before proceeding with 5-min test and control conditions.” Bryan nods, and Jessica continues, “We will also continue taking ABC data outside of FA sessions, of course. At least 4 options! What other concerns do you have?” 

“Well,” Bryan says, “I wanted to scrap the cards from the attention condition. I felt like they were a distraction or a competing stimulus.”

“OK,” Jessica rewords what Bryan said. “So, you’re saying that, if attention deprivation is an establishing operation for aggression, then having something else to do while he is attention deprived might decrease the probability of aggression maintained by attention?”  

“Yes, exactly,” Bryan agrees.  “And I feel like the control condition, where he has free access to his iPad, even if it is a high-preferred item, is not exactly a control for attention.” 

“Well, you were also giving him noncontingent attention while he had the iPad, but I can see why you’d feel your attention to be irrelevant in that condition,” Jessica remembers how Mateo seemed to ignore everything Bryan said during the control condition. “OK, we will rethink the test and control conditions.” 

“Great,” Bryan continues, “I’m also curious about the Practical Functional Assessment I’ve been hearing about. Is it too late to switch to that?”

Jessica smiles and shakes her head. “Nope! That’s a bigger conversation, but, the short and skinny is that the Practical Functional Assessment, formerly called the IISCA and SCA, simply provides another way to implement the contingencies in the test condition of the FA. For instance, instead of Rose’s condition only testing for the effects of attention on aggression, we could arrange for it to test an attention and escape function simultaneously. The interview did not suggest an escape function—at least not in the usual sense of escaping from task demands—but it’s possible that escaping the presence of another person, especially when preferred items are around, is a controlling variable.”

She glances at her watch. “I need to get to my next observation, but you have some great suggestions for where to take it next. The FA process can take some time. Try not to be discouraged. Yes, we want to be quick, but we don’t want to rush the process. Why don’t you instruct his techs to continue pairing, probing mastered tasks, and taking ABC data for now? We can chat at the end of the day and come up with a more formalized plan for how to proceed.” 

Bryan nods and says, “Thank you for your help. This is such a great learning experience. I look forward to meeting with you at the end of the day. What’s your drink of choice?” 

“Red,” Jess says breezily. “Oh, you mean coffee. None for me, you caffeine addict!” She laughs but sees the disappointment on his face. “Hot chocolate, if you must,” she concedes, as she rounds the corner out of sight. 

“Until then,” Bryan says, as he packs up the session materials and sends his techs on their way, with a big thanks and instructions to walkie if they need him.

To be continued… 


Written by Dr. Jennifer N. Haddock, BCBA-D


Dr. Haddock is currently an Adjunct Professor at the University of Kansas, where she teaches in the online master’s program in the Department of Applied Behavioral Science. She also writes for her own blog, Everyday Behaviorist, and provides continuing education and performance management consulting for ABA companies. Dr. Haddock began working with neurodivergent populations as an undergraduate at the University of North Carolina, Chapel Hill, in 2003. She was introduced to behavior analysis after graduating in 2005, when she worked at The Mariposa School for Children with Autism. It was love at first natural-environment-teaching procedure, and she never looked back. In the 17 years since, she studied clinical psychology at North Carolina Central University; took an online course sequence in behavior analysis from the Florida Institute of Technology; completed her master’s of science at California State University, Los Angeles; and obtained her Ph.D. from the University of Florida. She subsequently completed a Postdoctoral Fellowship on the Neurobehavioral Inpatient Unit at the Kennedy Krieger Institute and was an Assistant Professor at McNeese State University before moving to her home state of North Carolina to be closer to aging family members. During and throughout the past two decades, she has conducted research and provided clinical and consultative services for people and ABA agencies with various needs. She is unfathomably grateful for all of the learning, teaching, and life-improving opportunities that have and continue to come her way. These days, you can find her teaching online courses in behavior analysis; consulting with ABA companies; guest reviewing for behavioral journals; driving between North Carolina and Georgia; spending time with her family and dog, Risley; teaching and practicing yoga and meditation; gardening; co-hosting the Behaviorist Bookclub Podcast, and/or writing for Everyday Behaviorist.

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