• Decrease Font Size
  • Increase Font Size
  • Contrast

Introduction to Autism, Part 1: What is Autism?

Written by Dr Melanie Heyworth

Often at Reframing Autism our priority is on educating people on what Autism is not. We spend swathes of time debunking myths, righting misconceptions, and challenging the assumptions and stereotypes that contribute to the stigma and discrimination directed against the Autistic community. But, as we wrapped up our 2020 work, the RA team realised that, in our fervour to correct wrongs, we have yet to say clearly what Autism is.

This blog is thus the first in a series we will write as an introduction to the essentials of Autism. Over the series, we will cover topics like early developmental signs of Autism, first steps to take after a formal Autism identification, neurodiversity (what is it and why do we care?), and common co-occurring conditions.

But, before we can address any of those areas, we need to create a shared understanding of what Autism actually is, and how we might understand it, to frame and define it.

The purpose of this piece, then, is to explain the Autistic experience, or how Autism is manifested in Autistic people’s behaviours and experiences of the world. I realise that, technically, this piece is a description rather than a definition, and as a subjective description it could never capture the vast diversity of Autistic experience. Nonetheless, for most people, I hope, it will be sufficient.

So, with that in mind, let’s get to the crux of the matter.

In essence, Autism is a neurodevelopmental difference. Autistic individuals’ brains develop in distinct ways that do not correspond to how “typically developing” (“TD”) brains are expected to develop. Thus, Autistic individuals think, process, sense, move and interact atypically.

Let’s start with thinking.

One of the hallmarks of the Autistic experience is “orthogonal thinking” or an “orthogonal mindset”. The word orthogonal is defined as “not pertinent to the matter under consideration” (deriving from the Euclidean geometric definition of right angles, or of things perpendicular to each other). Orthogonal thinking is the ability to draw on ostensibly unrelated elements to inspire new perceptions and ideas (in contrast to “linear thinking”).

There is neurobiological evidence which explain why orthogonality is so much a part of Autistic thinking. For my purposes here, though, it is enough to say that Autistic individuals engage many more – and different – brain regions when we process incoming stimuli than TD brains. Autistic brains have additional neuronal pathways (termed “hyperconnectivity”) that are diffuse throughout the brain.

I want to make the point here that “hyperconnectivity” is a value-neutral term. More does not necessarily equate to better (or, indeed, worse) connectivity or processing. Hyperconnectivity comes with strengths and challenges, as I’ll discuss further below. Autistic hyperconnectivity simply “is”; it is a difference that impacts the way that Autistic people are, which is neither preferable nor inferior to the way that TD people are.

As a TD brain develops and matures, diffuse connections become more focal (so only the strictly “relevant” regions of the brain “fire” at different stimuli). The Autistic brain, however, does not generally become more focal, so that our connections remain diffuse throughout our lives. Essentially, this dispersion of “firing” neuronal pathways means that Autistic individuals draw on many different regions to interpret and process incoming stimuli.

It is unsurprising, then, that we make connections where others see none, or draw together what seem like disparate experiences or ideas to achieve new and exciting innovations, because the neuronal pathways in our brains are “lighting up” and connecting in unusual and new ways as we process information.

Our brains are wired for seeing patterns and making connections that are not obvious.

Autistic brains are also known for imagining and playing differently to TD brains. It is important to emphasise here that Autistic people do not lack imagination, nor do they eschew “play”. Rather, the way we imagine and play is informed strongly by our orthogonality, and they are thus expectedly unexpected.

What about processing?

Those atypical, diffuse connections throughout our brains might give Autistic individuals our characteristic orthogonality, but with that many connections “firing” simultaneously, Autistic brains are not particularly efficient at shifting rapidly to new focuses.

This means that transitions can be challenging for the Autistic person.

We also know that Autistic neuronal connections have an increased duration – that is, they last longer – when compared to TD connections. Autistic connections linger such that we find it harder to process new or unexpected stimuli, or to transition or switch between processes without sufficient notice.

Dispersed, lingering connections also contribute to Autistic inertia. Autistic inertia is Newtonian in quality: many Autistics find it difficult to begin something (anything!), but equally difficult to stop that thing once they begin. This principle has fundamental implications for how we might be motivated to start a task: it takes effort and determination to engage so many regions of the brain, and to filter, prioritise and organise the multiple tasks and processes required in even basic daily activities.

Autistic inertia also contributes to differences in the way we transition. Once we have begun a process or task, it is (quite literally) all-consuming, so we need careful preparation to transition from a task or between processes (especially if they are not “finished” or “complete”) because our whole brains are involved in the current task or process.

It’s also more challenging to prioritise stimuli when multiple brain regions are clamouring for primacy, so many Autistic people find it difficult to filter stimuli. For many of us that car revving its engine, or the birds chattering, are equally as important to our brains as the voice of our teacher or the facial expression of our friend. So, another frequent aspect of Autism is that Autistic individuals take in much more stimuli, which triggers much more scattered connections in our brains, and “lights up” regions that are unlikely to register in a TD brain.

All of this makes for very busy brains.

When we start to interrogate the actual regions of the brain that are hyperconnected, we see that there are significant differences in the way that Autistic people sense the world around them and move through that world. Thus, the regions connected to interpreting sensory stimuli are very often hyperconnected in Autistic brains, as are the regions which mediate socio-emotional analysis and reaction.

I doubt it will surprise many Autistic people to learn that we can see hyperconnectivity in the regions of Autistic brains involved in, for example:

  • interpreting touch and pain sensation,
  • proprioception (the position, movement and action of our body),
  • mediating the vestibular system (balance and movement coordination, and spatial orientation),
  • auditory processing,
  • understanding visceral and somatic sensations,
  • interoception (the sensations inside our body),
  • moderating and facilitating sleep,
  • recognising faces,
  • controlling facial expressions,
  • emotional recognition, understanding and expression (in oneself and in others),
  • empathy,
  • social cognition,
  • attention, and
  • risk-taking.

These are all areas in which our Autistic brains process atypically, and which others’ notice (externally) our atypicality. It is not – emphatically not – that Autistic people do not experience these things at all. On the contrary, we often experience them more than our TD peers.

The unique connectivity in our brains means that the Autistic experience of empathy, touch, sound, sleep, and emotions are often more overwhelming, more prominent, more intense because of our hyper-connected, busy brains.

So, what about Autistic interaction?

Alongside hyperconnectivity in certain regions, Autistic brains regularly have fewer connections in other regions when compared to TD brains. In particular, our “default mode network” (or “DMN”), which is strongly correlated to high-level self- and social-cognitive processes (like Theory of Mind), often doesn’t mature as expected and has reduced connectivity.

Like hyperconnectivity, hypoconnectivity doesn’t mean that Autistic people are inferior or disordered, or indeed superior, in their processing, but simply different.

The point to take away is that Autistic people have significantly different connectivity in brain regions that are characteristically associated with Autistic behaviours. It is likely that the hypoconnectivity in the Autistic DMN contributes to differences in the way in which we interact with others, form and define friendships and relationships, communicate, and experience and display emotions, especially given that many of these processes are also arbitrated through the areas of Autistic hyperconnectivity explained above.

In summary, then, Autistic people have atypical brains that mean we do many things differently. Importantly, there is no one “Autistic” way of communicating, interacting, reacting, perceiving and sensing. These are simply the external markers of the Autistic brain’s fundamental differences.

We present differently to those with TD brains, but so too, we present differently to each other.

The exact nature of these Autistic brain differences I’ve described is unique to each Autistic individual. Ultimately, they inform the way in which Autistics experience their Autism, and the way in which non-autistics experience another’s Autism.


Whether you are Autistic, you love someone Autistic, or you work with Autistic people, we want to hear from you.

Anyone who is committed to achieving inclusion and acceptance for the Autistic community can take advantage of our educational program by subscribing. Subscription is free and offers you priority access to all Reframing Autism events.


Sign up with your email address to receive news and updates.