This varies a lot with context. Some of the time, it sounds full of events – so many things happening at many different spatial and time scales. Other times, I’m not aware of the world outside my mind at all.

This is difficult to answer. I was aware as a child that I was sometimes aware of detail that other people ignored. But nobody – including me – ascribed any importance to this. The first time I can recall it being useful was as a teenage musician: I could hear very easily when something didn’t sound right – a note, a dial on an effects pedal.

Generally, my working assumption was that my perception and experience was much the same as anyone else’s. I thought my cognitive style and social experiences were within what one might expect for a bookish, shy man. I only really started to question this when my daughter was referred for an autism assessment and I found myself explaining to the psychologist that her behaviours were perfectly normal – because I did them too.

A lot of uncertainty and second-guessing myself collapsed. I found some validation in being diagnosed, and I was relieved to reach the end of a long wait. Of course, by then I had read a lot about autism, including some academic papers critical of the diagnostic process itself – so I also felt a bit annoyed at myself for being so easily pleased by a flawed and variable concept. But on the whole, I did think they got me right.

In the period after diagnosis, I experimented with thinking of myself as autistic. Since part of this involved thinking and talking about autism most of the time, and getting cross about many injustices visited on autistic people – especially on me – I became quite unbearable to those around me. I think I’ve calmed down a bit now.

Just normal, at least to me. And some years after diagnosis I once again think of myself as normal. I agree with the autistic philosopher Robert Chapman that autism is a political category, not a natural category. Most societies today have quite narrow assumptions about normal behaviour and are intolerant of the traits associated with people we label as autistic. One could imagine a slightly different society where weirdness would be unremarkable. I suppose the neurodiversity movement is trying to change our current society into this more tolerant one. I will continue to regard my life as normal for a human.

Lots of things just feel like they don’t fit properly. Many things – and people – make more noise than they need to. Neurotypical non-verbal communication is so rapid and pervasive that I sometimes feel I am continually radiating unintended signals. Sometimes people get alarmingly angry about tiny details being wrong: I delay a fraction of a second too long in responding, I forget to arrange my face the right way. Autistic pleasures must often be hidden. The stigma attached to being autistic is depressingly, irrationally powerful. The cognitive effort in dealing with all this is real, and would be measurable – brains use a lot of resources to run.

I am going to choose carefully here because I feel ashamed of my meltdowns and shutdowns. When one generally presents the identity of a successful professional to the world, public moments when that suddenly collapses feel shameful – and I know this shame is the operation of societal stigma in the form of internalised ableism, but that does not make it any easier.

My example occurs at an academic conference, in a poster session. The room was very crowded, hot and noisy – about a hundred researchers shouting at each other over the din. I was trying to read a poster and finding it impossible to think. I put my hands over my ears. Someone asked if I was OK, but I found I couldn’t speak. I realised I had to leave, but even my motor control had become clumsy – I think I knocked over one of the poster stands on my way out. I spent the next two days hiding in my hotel bedroom and left the conference without speaking to anyone.

These days I try to plan better to avoid situations where I might be unable to regulate myself. But this isn’t always possible.

I’m not sure. Being diagnosed so late – I was 52 – means that not masking can sometimes feel more awkward than masking. My experience of masking is not very uniform: there are some aspects I’m not very good at, or don’t habitually do. For example, I have never been very good at remembering to arrange my face into an appropriate expression, with the result that people seem to think I am depressed or angry most of the time.

For a contrasting example: experimenting with not making eye contact has been a bit of a revelation. It is so much more comfortable not to. And people really don’t seem able to tell if you perform a near miss – a nose or an ear. The research literature indicates that chronic masking is pretty bad for us, with links to worse mental health outcomes. That’s one reason why time on my own is so important.

For a long time, it didn’t. In an ironic reversal of autism research, I spent thirty years as an undiagnosed autistic running dozens of laboratory listening tests on my presumed neurotypical experimental participants. While reading about autism around my own diagnosis, I began to think that autism research had not done a very good job of explaining or even characterising differences in how autistic people hear and process sound. I was pleased to find that my non-autistic colleagues thought this topic was very interesting too.

So these days, my research is somewhat shaped by my own perception, and those of other autistic people. Together with my students, I try to devise experiments to explore formally the kinds of experiences that autistic people report – such as being able to experience heightened detail on multiple different scales, or finding the noise of background speech intolerable.

Aural diversity is the idea that there are many kinds of differences in hearing and processing sound between individuals and groups. The current medical model assumes most people have “normal” hearing, with the rest classed as impaired. Aural diversity proposes a better model: a spectrum of all the different kinds of hearing differences – explicitly patterned after the neurodiversity concept, but much broader.

Besides neurodivergent hearing differences, there are people with age-related hearing loss, noise-induced hearing loss, tinnitus, hyperacusis, auditory processing disorder, all the various d/Deaf communities, misophonia, and so on. Normal hearing is quite tightly defined – the age range is only 18–25 for a start – so it actually applies to a small minority of humans. The rest of us are not being properly catered for.

People should care about aural diversity because if widely adopted it should lead to a world where sound environments are a better fit to the people using them. They might also care about it because it is true.

That a lot of hearing differences are more common than often thought but hidden, and that the experience of them can vary from day to day. Tinnitus is a good example of both.

I think they might be quieter, calmer and more predictable.

Of course, though I’m not sure about how unintentional it is. I don’t mean that designers set out to exclude one group or another. But almost all design decisions are driven by money and regulation, so it is difficult to make accessibility the norm.

Providing more information about each space in a structured form, so that users – especially autistic users – know what to expect and can manage their own access accordingly.

I think a good example is given by the Royal Art Collection in London: they use photos and text to show you what to expect and plan your visit in detail. They don’t shy away from warning of potential sensory hazards. See: rct.uk – neurodivergent visitors at the King’s Gallery

I was approached by an existing trustee. I think the Board wanted someone working in higher education. Part of the reason I applied was because I thought I AM could do with some autistic representation on the Board.

I don’t forget that the name means that we have been entrusted to take these decisions on behalf of the users and beneficiaries of the charity. It can actually be a helpful guiding principle: which path will most benefit I AM’s members?

Perhaps that autistic people are everywhere. NHS data indicate that the great majority of autistic people are undiagnosed adults, many of whom will not know that they are autistic. Most autistic adults have no support at all.

That autistic people lack empathy, or have no need for social interaction.

When an autistic person is valued for all of who they are, instead of their mask.

Autistic people have always been part of the human race, and we exist in all societal roles. You will have interacted with many autistic people, often without knowing it. Autistic people can bring many strengths to work and society, and groups of people with diverse thinking styles can often achieve a great deal. But autistic lives are valuable independently of any economic contribution they make, simply because they are fully human.

Being misunderstood or alone seems to be an inevitable feature of being autistic in a world made for neurotypicals. It may be some comfort, therefore, that you are not alone after all – in the sense that many other autistics have experienced what you are experiencing now, and will fully understand and empathise with you. Furthermore, these other autistics have not all remained stuck where you are now but have instead found a way to work around the current difficulty, sometimes by connecting with each other.

Change is hard for most of us, even a change which might take us out of a bad situation. So don’t be hard on yourself for finding this difficult. Try to look after yourself; the world needs you here.