Both neurotypical and autistic people sometimes use defense mechanisms, albeit often in different ways and in different circumstances. When people use defense mechanisms, they are typically not aware of it. Defense mechanisms often go hand-in-hand with logical fallacies, as both are ways that people defend their egos and support their opinions/arguments/beliefs.
Therapy (with an autistic-friendly therapist) can be extremely helpful for identifying your own use of defense mechanisms, and replacing your use of unhealthy defense mechanisms with healthy defense mechanisms and coping skills.
Why people use defense mechanisms
People who hold themselves to very high standards may be more likely to use defense mechanisms. This is because they have a deep fear that if they have done something wrong, this would mean that they are a terrible person, or that their identity of having a certain character trait, such as being intelligent, would be invalidated. As a way of protecting ourselves from having to think bad things about ourselves, our brains use defense mechanisms, often without us being aware of it. Our perception (can add more science here) of situations is fluid, and our brain is very skilled at altering how we view situations to align with what it expects (confirmation bias).
What if I use defense mechanisms?
It can be difficult to see and to admit to your own use of defense mechanisms, and this is where a skilled therapist or a kind friend can be very helpful. If you use defense mechanisms (most people do), it does not mean that you are lying or bad. In fact, people with trauma may be more likely to use defense mechanisms, as this can be the brain's way of protecting oneself from future trauma. I have identified my own use of defense mechanisms through neurodivergent-friendly therapy, and I found that being honest with myself and others about my use of defense mechanisms always works out better than trying to pretend I am perfect all of the time. Neurotypical people and autistic people alike can appreciate honesty and humility. Most people feel more comfortable around people who admit to making mistakes and being wrong about things.
It is absolutely impossible for *anyone* to never make a mistake or be wrong about anything. I have found that it is much easier to accept this fact about myself and others, as it allows me to forgive myself and others and give people the benefit of the doubt.
Dealing with defense mechanisms
Autistic people tend to be very logical, so they may easily pick up on when others are using defense mechanisms and their arguments are flawed. This can be frustrating, because it may be difficult to comprehend how someone seems to convinced of something that seems to clearly not be true. It is important to keep in mind that when people use defense mechanisms, they often genuinely believe that what they are saying is the truth. Therefore, it is respectful to try to acknowledge their feelings and not invalidate their perspectives/experiences. However, this is not to say that people never lie or deliberately misrepresent facts. In general, it is easier to get along with people if you try to err on the side of giving people the benefit of the doubt (i.e. treating them as as honest or deserving of trust despite your doubts) when they say things that seem to be inaccurate. People often use defense mechanisms to make themselves feel better, rather than to try to trick you or lie to you. Sometimes people will use defense mechanisms as a way to argue against opposing opinions that make them feel threatened. It is very easy to feel frustrated or upset when you notice someone doing this, and that is totally normal and okay. It can be helpful to try to think about different reasons why someone may be doing this, and to remember that all people think about themselves and their own feelings more than they think about anyone else. Therefore, if you perceive something someone said as hurtful, and inform them of this, they may become defensive and deny that they "said anything wrong." This is because when people are told that they may have hurt your feelings, they may interpret this as you accusing them of being mean or bad. When this happens, both parties can take accountability, as what occurred was a miscommunication, since neither of you intended to hurt each other.
It is always best to try to take accountability and validate someone's feelings when they express that their feelings have been hurt by something that you said or did, even if you don't agree that it was hurtful, or you did not intend to hurt them. This sets a good example, so they are more likely to do the same for you in the future.
Types of defense mechanism
Can add descriptions of healthy vs. unhealthy defense mechanisms