
In this series, I dig a little deeper into the meaning of psychology-related terms. This week’s term is behavioural experiments.
Behavioural experiments are a cognitive behavioural therapy (CBT) technique to test out beliefs in real-world conditions. It’s like being your own social scientist. Behavioural experiments are commonly used in the treatment of anxiety disorders to test unrealistic predictions and provide exposure.
We often make predictions about the world based on our own internal models about how the world works. Yet the way we think the world works doesn’t necessarily match up all that well with reality. In science, that kind of thing is tested by selecting an appropriate setting and running an experiment to deliberately gather evidence that can either support or go against a hypothesis. A behavioural experiment is the same kind of thing.
The process begins by selecting a belief to test and rating the strength of the belief. If it’s helpful, you can break this rating down into how strongly you believe cognitively and emotionally; it’s not uncommon for emotional attachment to persist even when there’s some cognitive recognition that it might not be reality-based. The next step is deciding on a setting/context and a way to test it. You’ll want a setting that allows you to actually test the belief without a lot of noise getting in the way.
Examples of behavioural experiments
Potential experiments include:
- seeing what happens when safety behaviours are dropped (safety behaviours are things we do to try to feel safer, but they don’t actually increase physical safety and end up just perpetuating anxiety)
- deliberately doing a behaviour you’re worried about exhibiting (e.g. being shaky or dropping something) to see if the consequences match your predictions
- deliberately exposing yourself to an anxiety-provoking situation to see if the feared outcome will occur
- test out a feared situation through role-playing or replicating some elements of the context but in a controlled situation
- if you’re working on adopting new beliefs, testing those out in real-life settings
- surveying other people to see if they think what you assume they do
- discovery experiments can involve searching for information that may confirm or deny a belief
- testing out two different predictions to see which turns out to be closer to the actual outcome
- having someone else conduct an experiment and directly observing how it turns out
It’s important that the experiment be set up so that nothing happening, or people doing nothing, wouldn’t act as evidence to support your prediction. Doing nothing is always easier than doing something; for that reason alone, people doing nothing is a likely outcome.
Evaluating the outcome
Once the experiment is completed, the next step is to compare the expected and actual outcomes, and determine if the strength of the belief has changed. If the outcome was different from what was expected, that becomes part of the evidence base that the belief is unrealistic. We have a natural cognitive bias to pay more attention to the negative, and evaluating the results of a behavioural experiment can be a way of rationally working through experiences that aren’t negative.
If the outcome is in fact what was expected, that could indicate that the belief itself isn’t the issue. At that point, a better place to focus might be on developing coping strategies. For example, if I’m anxious about people noticing my tremor, and people do sometimes notice it (which is true in my case), the focus could shift from “what if they notice” to “how am I going to cope most effectively when they do notice?”
Usefulness of this tool
For beliefs that have built up over years, doing a behavioural experiment or two obviously isn’t going to make them change overnight. It’s a tool in the toolbox that may be useful for some people, and may not be for others.
While I’m a logical-minded person, and this appeals to me on that level, with my own particular brand of crazy, I don’t tend to make a lot of predictions. When I do, it tends to relate continuation of already established patterns of outcomes. While I occasionally get some physical anxiety symptoms with my depression, I don’t avoid doing things because of anxiety. I avoid situations that repeatedly produce dysphoria, but I don’t need a behavioural experiment to confirm it; it’s already been confirmed; the issue is what to do about it, not whether it’s true.
Have you ever done behavioural experiments? How did that turn out?
Worksheets from PsychologyTools or TherapistAid can help with the process.
References
- CBT4panic.org: Behavioural experiments
- Oxford Guide to Behavioural Experiments in Cognitive Therapy
- PsychologyTools: How to use behavioural experiments to test what you believe
The post Psychotherapy Alphabet Soup: CBT, DBT, ACT, and More provides an overview of a variety of different therapeutic approaches.

The Psychology Corner has an overview of terms covered in the What Is… series, along with a collection of scientifically validated psychological tests.
I did a behavioral Case study and (later) behavioral experiment, as a requirement of my undergraduate Psychology degree. I was fading, so I don’t remember much about it. And, my work in Statistics is even worse!
Statistics wasn’t my friend either.
Good article. I think CBT saved me and I’ve always been my own best lab to run experiments.
Yeah, I think it’s made a big difference for a lot of people.
I don’t think I did them consciously but they definitely helped me conquer a lot of my anxiety around eating alone, entering different kinds of shops, going to the supermarket, going out for social gatherings etc.
That’s good!
They worked for me and my anxiety. And I loved the use of CBT when working with patients who had schizophrenia. To see their faces, that lightbulb moment — when they realised that no, the t.v. was not talking to them specifically. However, don’t try this at home – these behavioural ‘experiments’ took many anxiety-provoking months, working collaboratively with the patients, their families and Consultants.
I can imagine.
I don’t know if this counts, but when I was agoraphobic, my psychiatrist at the time had me make a list of errands I needed to do from least scary to most scary. I remember grocery shopping was least scary (which is weird because it still terrifies me most). Then she had me do the first thing on the list over and over until I was less terrified. Then I could move on to the second. This way I wasn’t overwhelming myself with all the errands at once. That method and anxiety medicine is how I’m able to leave the house today.
That’s great! And yeah, that idea of making a fear hierarchy and starting at the lowest level is a big thing in CBT.
I’ve always found exposure therapy and certain aspects of CBT tricky. If a situation doesn’t go to plan and you felt bad about it, it felt to me that CBT was invalidating. It’s alright telling yourself ‘it wasn’t so bad’ but the problem for me is actually believing it.
That definitely makes sense.
You do seem like a very logically-minded person. You remind me a little bit of my pastor, in particular as having a reverence for the scientific method. Um, I have read this three times and still do not fully comprehend it. I don’t have very strong reading skills, unfortunately. I’ll try again later tonight.
I do like my logic. Another way of putting is that we all have our own set of knowledge that we’ve acquired, and it lives in our house. Some of it may be tucked away in the crawl space where we’ve forgotten it, but it’s still there. Then there’s the knowledge that lives in the other houses in our neighbourhood. We haven’t been inside to take a look around, but we still know that it’s there. But there’s also knowledge living in a village in Siberia that we’ve never heard of. The problem comes if we fail to recognize that the world doesn’t just consist of the knowledge in our town.
To put a religious spin on it, it’s sort of like the fundamental flaw in someone thinking that the knowledge they’ve accumulated comes anywhere even remotely close to to the amount of knowledge that’s known by an omniscient God. There’s value in recognizing that we are small compared to that kind of vastness.
You’re brilliant.
Thank you!
It’s so obvious, it’s not even a compliment. 😉
Oh my, I realize just now I explained the wrong post! i guess that’s one of the risks of reading comments in the Reader. Brilliant or not, confusion is equal opportunity!
I realized that your explanation didn’t pertain precisely to this particular post. But what was the post pertinent to the explanation? I’d like to read it, if I haven’t already.
It’s the one I posted today on what we don’t know we don’t know.
Okay. I’ll read that after a bit.