Psychedelics and the mind’s eye: 5 Questions for aphantasia researcher Joel Pearson
Pearson discusses if psychedelics can turn on mental imagery.
Close your eyes and imagine a red apple. How vivid is the image? Can you see the bright red skin, possibly even a stem? Or is it more blurry? For people with aphantasia, an absence of mental imagery, they see nothing at all.
The neurologist Adam Zeman began publishing scientific papers in the 2000s on people who had lost—or never had—mental imagery. It prompted thousands to reach out to him to share that they too only saw darkness in their minds. It’s now estimated that aphantasia affects 3 percent of all people.
A few of them have claimed that an experience with psychedelics gave them the ability to mentally visualize. In one 2018 case report, a man with self-diagnosed aphantasia started to see images of his hometown and father 30 minutes after consuming ayahuasca. He continued to have mental imagery after the drug wore off. “It feels like this experience…has slightly opened up my mind’s eye and allowed me to experience internal images like I have never had before,” he told researchers. “Ayahuasca turned on my mind’s eye, even if it is faint.”
Such stories are rare but intriguing. The Microdose talked to aphantasia researcher and neuroscientist at the University of New South Wales, Joel Pearson, about the experience of aphantasia, and the potential consequences if psychedelics could actually switch on a film reel in the mind.
I have aphantasia, and yet I find it hard to explain. How would you describe the experience of having aphantasia?
I have imagery, so I can’t give a first-person description of it. The best analogy I have is that I have trouble packing when I’m going from a cold climate to a hot climate, or vice versa. I pack for where I am at the moment, so I suffer from this presentism. If it’s winter [in Australia] and I’m going to a conference in Florida where it’s going to be really hot, I think I’ve got to bring long pants and sweaters and jackets. I have a lot of trouble imagining that change in temperature. That’s the closest I can get to capturing a glimpse of what it might be like to have aphantasia.
What I hear from the other people I talk to ranges. They see black on black; black velvet on black velvet is one description I’ve heard a lot of times. There’s a shadow experience—where it’s almost something, but not. It’s almost a black thing on a black background, but not.
The black object can maintain some spatial representation of an object despite not being able to generate an image of an object, the colors, or the surface. People have won memory competitions who have aphantasia, and instead of a mind palace, they use a mind-spatial layout of their neighborhood, where they have spatial representation, but no objects in that space. That’s hard for me to understand.
People will often try to visualize apples or red stars to self-diagnose aphantasia. How do researchers determine who has it?
The most popular way to assess imagery is the Vividness of Visual Imagery Questionnaire. You can do it very quickly, but it has some downsides. It assesses two different things simultaneously: someone’s vividness of their imagery, but also their criteria for how they decide their vividness number. Me and you could have the exact same mental image, but give it very different numbers because of our criteria for how to make that decision. It relies heavily on the word vividness, and some people have different interpretations of that word. They might interpret it to be an emotional thing. Some people take it to just be a visual, sensory thing.
We have developed a number of different, more objective techniques to assess visual imagery in the lab. The binocular rivalry method uses a visual illusion as a measurement tool to measure the sensory strength of visual imagery. Another method we use capitalizes on the emotional content of imagery. You can ask people to imagine emotional scenarios while they’re connected to a thing around their finger which measures changes in micro-levels of sweat, a proxy for emotional arousal. People who have aphantasia, when they read these emotional scenarios, their skin response was pretty bumpy and more or less flatlined. Those with imagery had an increase. More recently, we’ve developed a way to use pupil response. It turns out if you can imagine bright objects versus dark objects, your pupil will constrict or dilate in response to that, just like if you look at a bright object or a dark object. Of course, there’s fMRI, where you could scan blood oxygen levels in the visual cortex, but that’s very expensive.
When did you first hear that some people with aphantasia were able to visualize things in their mind’s eye after taking psychedelics?
I have heard people say that they have had an imagery experience from different kinds of meditation and also from taking psychedelics. I’ve also heard from plenty of people that have tried psychedelics and not had any visual experience.
There’s big variation in the reports I’ve heard anecdotally from people, which makes me think that psychedelics are not going to be a way to give every person imagery who doesn’t have imagery. There are a few case study reports that were done retrospectively, which means no one gave them a questionnaire or measured imagery beforehand. We’re relying on their memory, and comparing that to some period later in time.
We don’t want to throw these stories out, but there are a lot of unknowns there. I’m also hearing anecdotal reports that people have tried [psychedelics for aphantasia] after they saw these reports, and it didn’t move the needle for them. It makes me think that this is going to be for only a subset of the population. We have no idea what the percentage is. If we tested 100 people, how many would this work for?
If psychedelics can bring back visualization in some rare cases, what do you think is happening in the brain? Can we learn about aphantasia from psychedelics?
There might be two things going on. If you have some conscious visualization experience while the [psychedelic] molecule is active, having a flash of that shows you what it can be like, and it can teach you what to pay attention to. We also know that psychedelics put the brain in a very plastic state where it can speed up brain changes that would normally take much longer.
Aphantasia itself is very heterogeneous. There’s all different types: pure visual, pure auditory, full multi-sensory. It’s not one shoe that fits all. If we zoom in on visual aphantasia, it may be that there are different types. There could be one subtype where people have unconscious imagery; there are still images being formed in the visual cortex, it just remains unconscious for some reason that we don’t yet know. Another type, call it 100% pure aphantasia, could have no unconscious image.
It could be that if you have unconscious imagery, taking psychedelics may make that conscious, help you pay attention to it, and amplify that, combined with the brain plasticity. Psychedelics would shed light on that theory of unconscious imagery as a subset of those with apantasia. From that point of view, psychedelic studies could be really interesting for the study of mental imagery.
People with aphantasia might be curious about “switching on” mental imagery, but you have recently written that caution is needed. Why?
There are psychedelic studies happening for mental health reasons around the world, and this should be mentioned in the ethics declarations before people take part in the study: it is a possibility that if they don’t have imagery, that may change afterwards.
While the psychedelics might be used to treat PTSD, increasing imagery may counter that. Strong imagery, generally speaking, is associated with worse experiences of anxiety, neurological diseases, and mental health. There have been associations between imagery and strong thoughts, and an emotional amplification of those thoughts because they become an image in your brain.
That’s one of the things that’s held us back from doing a big study on this. If you gave a large number of people imagery who had never had it before, and it was basically irreversible, what if half of those people then had trouble sleeping? If they had intrusive thoughts? They would not have had the years of practice to learn the strategies to deal with these thoughts, and we’d be in a sticky situation.
I’m not trying to be alarmist or freak people out, but from all the data we have, there is probably—everything else being equal—more downside to having very strong imagery than upside. People who don’t have imagery often think that getting imagery would solve a lot of problems in their lives, but we don’t see a lot of data to support that.
This interview has been edited and condensed for clarity and length.
