rigid thinking (cognitive inflexibility)

Cognitive inflexibility, also erroneously referred to as rigid thinking, black-and-white thinking or all-or-nothing thinking, is one of the diagnostic characteristics of autism, but can also be present in ADHD and AuDHD. It accounts for differences in perspective-taking, adaptability, and what clinicians call “set-shifting” — the ability to move between tasks, rules, or strategies when circumstances change. But as with many other traits that have been named after the observable behaviour instead of the internal experience, there is a lot to unpack here. The internal experience is better understood through monotropism: a processing style that goes deep rather than wide. The depth that makes sustained focus, thoroughness, and reliability possible is the same depth that makes switching costly. The difficulty and the strength are the same mechanism.

If you’ve spent your life being called rigid, stubborn, difficult, or “too much” — for holding people to what they said, for needing a plan before you could settle, for caring about consistency in a world that treats consistency as optional — then “cognitive inflexibility” is the clinical term for what you’ve been living with. And like most clinical terms built by people observing from the outside, it describes how the trait looks rather than what it does.

The stigma of “rigidity”

The word “rigid” carries moral weight. It implies stubbornness, petulance, selfishness — a character flaw rather than a cognitive style. “Cognitive inflexibility” sounds more neutral, but anything with “cognitive” in front of it makes people assume their brain is damaged, their thinking is broken, and their intelligence is compromised. None of that is accurate. This has nothing to do with intellectual capacity.¹ And “rigid” sits uncomfortably close to “frigid” — another word used to reduce a full, complex internal experience to a single dismissive judgement made from the outside, locating the fault in you rather than in the other person’s unwillingness to understand.

What the label misses — what it has always missed — is that the internal experience of so-called rigidity feels nothing like what the word implies. When you look inward for the stubbornness, the inflexibility, the unreasonableness that others seem to see, you find something else entirely: consistency. Logic. Reliability. Taking people at their word. Processing deeply, caring about accuracy, and finding it genuinely costly to abandon something your brain has invested in fully.

What is the meaning of “rigid thinking”?

In clinical and diagnostic language, rigid thinking or cognitive inflexibility refers to difficulty shifting between tasks, perspectives, or strategies when circumstances change.² It includes things like perseveration (returning to a previous response even when the rules have shifted), difficulty disengaging from a current focus, and trouble generating alternative approaches to a problem. It’s typically measured through lab-based tasks in which people learn one rule and then switch to another. It’s considered a component of executive functioning alongside working memory and inhibitory control.

For decades, the dominant explanation has been the executive dysfunction model: the switching mechanism in the autistic brain is “impaired”, and it produces a cascade of rigid behaviours. This explanation has a seemingly straightforward logic: if you can’t switch, you get stuck, and if you get stuck, you become rigid. Simple.

Except the evidence doesn’t support that tidy story. A meta-analysis examining cognitive flexibility across multiple studies found highly inconsistent results, with outcomes varying by task type, age, comorbidities, and the way flexibility was measured.² It seems like this explanation is simplistic, and alternative explanations have better empirical support. A philosophical analysis of rigidity in autism reached a similar conclusion: the assumption that all forms of rigidity reduce to cognitive inflexibility is unmotivated by the research, and the construct itself is “too understudied and underdeveloped to represent a meaningful treatment target.”⁴

In other words, clinicians have a name for what they see, but they haven’t done the work of understanding why it happens. The label came first. The understanding is still catching up.

Research increasingly suggests that cognitive inflexibility in autism has roots in how the brain is wired during development. Overactivity in a cell-level signalling pathway called mTOR leads to denser local neural connections and less efficient long-range communication between brain regions, which means shifting between mental tasks or contexts requires the brain to push signals through more noise.

A different explanation: monotropism and the depth of focus

A more complete account comes from monotropism — a theory of autistic cognition developed by autistic researchers Dinah Murray, Wenn Lawson, and Mike Lesser.⁵

The monotropism model describes a processing style where fewer interests are active at any given time, but each one attracts more of the brain’s available resources.

Where a polytropic (broad-focus) mind has many interests gently aroused simultaneously — allowing easy movement between them — a monotropic mind concentrates its processing resources into fewer, deeper channels. The focus is more intense, the engagement more thorough, and the emotional investment in whatever currently holds attention is greater.

This means processing that goes deep rather than wide, and depth always comes with a switching cost.

When you’re deeply invested in a line of thought, a plan, a task, a conversation — when you’ve loaded the full weight of your attention into it — redirecting that attention means dismantling something substantial. Fergus Murray, who has written extensively about monotropism from an autistic perspective, describes it as loading a cart to the brim with thoughts and feelings, and then having to steer it round a sharp corner.⁶ The difficulty with the corner isn’t a “steering deficit”. The cart is full because the thinking was thorough in the first place.

Switching from deep processing is costly

Murray, Lesser, and Lawson describe what happens when the attention tunnel is interrupted without warning: “every unanticipated change is abrupt and is truly, if briefly, catastrophic: a complete disconnection from a previous safe state.“⁵ That language may sound dramatic to someone who can switch between tasks easily. For someone whose processing runs deep, it’s an accurate description of what an unexpected interruption actually feels like — a momentary collapse of the entire framework you were operating inside, before anything new can take its place.

This reframe matters because it changes what the “inflexibility” means. The depth of focus that makes switching costly is the same depth that makes sustained attention, thoroughness, and intense engagement possible. Fergus Murray proposed the term “autistic inertia” as a replacement for “executive dysfunction”: resistance to a change in state, including difficulty starting, stopping, and changing direction.⁶ Inertia is a property of objects in motion. The momentum that carries you deep into a thought is the same momentum that makes it hard to change course. One produces the other. You cannot have depth without the switching cost, because they are the same mechanism.

Rigidity is not constant

The switching cost that gets labelled as “rigidity” is not constant. It depends heavily on the context — and the research on this point is straightforward.

In social contexts, the cost is significantly higher. A study comparing autistic and non-autistic adults on an emotional shifting task found that the switching cost was substantially more pronounced when the stimuli were social (involving other people) than when they were non-social, and this difference was specific to autistic participants.⁷ In non-social contexts, the switching cost largely disappeared. Autistic participants could adjust to unexpected changes in non-social emotional situations at roughly the same rate as non-autistic participants.

This makes sense through the monotropism lens. Social interaction is inherently multi-channel: spoken words, tone of voice, facial expression, body language, unspoken rules, shifting expectations — all running simultaneously and all requiring processing. For a brain that works best in single-channel depth, that combination is structurally more demanding. The switching cost is higher because the processing load is already higher before any switching is required.

Petrolini and colleagues point out that in difficult social situations, most people become more rigid — they follow rules more strictly, they stick to routines, and become less tolerant of uncertainty.⁴ This is a human trait, not an autistic one: social overwhelm produces rigidity in everyone. But if autistic people navigate the social world at consistently higher cognitive cost, then many facets of what gets called “autistic rigidity” may be responses to that ongoing cost rather than expressions of a broken cognitive mechanism. The rigidity isn’t the condition, but what happens when you’re spending so much on social processing that there’s nothing left to spend on for flexible adaptation.

“Rigid” is not one thing

Part of what makes the label so unhelpful is that it gets applied to a collection of experiences that are actually distinct from each other.⁴

Petrolini and colleagues identified at least seven separate facets that all fall under “rigidity”.

These can be conceptually and empirically separated. You can have intense interests without insistence on sameness. Or you might experience intolerance of uncertainty, but don’t relate to black-and-white thinking. You can take rules seriously without having any difficulty switching between tasks.

They cluster together in autistic people more often than in the general population, but the clustering doesn’t mean they share a single cause — and treating them as though they do leads to interventions that miss the point.

Even within “inflexible attention” specifically, the picture is more varied than a single label suggests. Research using eye-tracking distinguished between “sticky attention” (being slow to disengage from a current focus) and “springy attention” (quickly returning to a previous focus after briefly attending to something new).⁹ These two patterns had different correlates entirely: sticky attention was associated with more intense sensory experiences, while springy attention was associated with reduced learning opportunities. Calling both of them “rigid” collapses a meaningful distinction into a useless generality.

The lived experience of being called “rigid”

For many late-identified neurodivergent adults, the word “rigid” arrived long before any understanding of why their brain works the way it does, and it was never a neutral description, more like an insult or an accusation.

The experience often goes something like this. There’s an agreement — a plan, a deadline, a stated commitment. You take it at face value because you communicate directly, and you assume others do the same. When the agreement shifts without warning, you’re thrown — not because you can’t handle the new plan, but because the old plan was already built into your operating framework and now the whole structure needs to come down. You say something about it. And instead of accountability for the broken agreement, you get: “Why are you being so rigid about this?”

Rigid? You mean consistent and reliable

The “rigidity” that people see from outside is often just consistency being punished and reliability being treated as a problem. Direct communication — saying what you mean and meaning what you say — being held against you when the other person was using language loosely and didn’t bother to flag that.

The accommodation work flows one way: you learn to ask more questions, to build contingency plans, to force vague commitments into concrete ones. “Does this deadline mean it has to be done by then, or is it a rough estimate? Can you tell me which part needs to be done by when?” Clarity work that benefits everyone involved, but that only you seem to be doing.

For people who carry a strong internal sense of themselves, this mismatch between the label and the inner experience produces frustration and confusion — a sense that other people are unreliable and the world is full of broken promises.

For people whose internal core is less settled (for example, due to trauma or adverse experiences), the damage runs deeper. When you look inward and can’t find the stubbornness or selfishness that “rigid” implies — when your internal experience is something entirely logical and consistent — but the label keeps arriving from the outside, a specific kind of erosion starts. You begin to distrust your own self-knowledge. The feeling that something about you is broken, or boring, or too much, takes root — not because you’ve found evidence for it internally, but because enough people have told you it’s true from the outside.

Years of this, before diagnosis, produce a particular kind of confusion: a person who doesn’t feel rigid, but who has absorbed the message that the way they operate is somehow not good enough. Reframing that experience — understanding that “rigid” was never the right word for what they are — is often where the repair begins.

A note for practitioners
The word “rigid” in a clinical report or a conversation with a client carries more weight than its technical definition. For late-identified adults, it often lands on top of decades of the same judgment from partners, parents, teachers, and colleagues. Reframing cognitive inflexibility as monotropic processing, as depth of focus with a switching cost, or as a nervous system that processes deeply and invests fully — rather than as a deficit to be remediated — can be reparative in itself. The client doesn’t need to be taught flexibility. They need the people around them to understand what the depth is for.

What actually helps with rigidity

Any approach that targets rigid thinking as the problem to be solved — through compliance training, repeated forced exposure to change, behavioural conditioning designed to increase “tolerance” of disruption, or interventions that reward flexibility for its own sake — is working against the person rather than with them. These approaches treat the switching cost as a behaviour to be eliminated rather than a feature of how the brain processes. And because the depth of focus and the switching cost are the same mechanism, suppressing one means suppressing the other. You cannot train away the difficulty of transitions without also training away the capacity for sustained, thorough, deeply invested thinking. That trade-off is never worth making, and it is rarely acknowledged by the people proposing it.

What helps is working with the processing style rather than against it.

More time for transitions.

A brain that processes deeply needs longer to disengage from one thing and re-engage with another. Rushing the transition adds social pressure on top of the processing demand, which makes both worse. Time is the cheapest accommodation available, and it’s consistently the most effective one.

Advance notice of changes.

A changed plan announced with enough lead time can be integrated before the current framework needs dismantling. A changed plan announced in the moment means demolition and construction happening simultaneously, while the person is also expected to be socially appropriate about it. The difference between these two scenarios is often the difference between a smooth transition and what observers describe as a “disproportionate” reaction.

Clearer communication from the start.

A significant portion of what gets labelled “rigidity” in relationships and workplaces is a mismatch between direct and indirect communication styles. When agreements are explicit, concrete, and mean what they say, the “rigidity” often vanishes — because there’s nothing ambiguous to be inflexible about. Clarity up front prevents conflict downstream, and it benefits everyone involved.

Identifying which facet is actually in play.

Since “rigid” describes at least seven different things⁴, knowing which one is relevant changes what might help.

• If someone’s “rigidity” is actually intolerance of uncertainty, the answer is more information, not flexibility training.
• But if it’s literalism, the answer is clearer communication, not cognitive remediation.
• And if it’s adherence to rules in social situations they can’t otherwise navigate, the answer is better support for navigating those situations — not abandoning the rules that make them manageable.

Treating all rigidity as one thing produces interventions that miss the actual need.

Environments that accommodate depth rather than punish it.

Open-plan offices with constant interruptions, meeting-heavy work cultures, rapid context-switching throughout the day — these are environments designed for polytropic processing. For a monotropic brain, each interruption collapses an attention tunnel that took real cognitive resources to build. Workplaces, classrooms, and living arrangements that allow sustained focus, with transitions that are signalled and paced rather than abrupt, make monotropic processing viable rather than penalising it.

Recognising the strength & the joy of monotropism

Monotropic depth produces thoroughness, sustained attention, intense engagement, and a kind of immersive absorption that broad-focus processing rarely reaches. It also produces joy.

The awe of noticing something nobody else saw because nobody else was looking that closely. The deep emotional connection to interests, people, and ideas that comes from giving them your full attention rather than a fraction of it. The satisfaction of going all the way into something rather than skimming across it. These experiences are worth having for their own sake — not because they produce useful outputs, and not because other people benefit from them.

Erasing the switching cost means erasing all of this along with it. The depth is not a consolation prize for the difficulty. They are one thing, and the thing is worth protecting.