Picture what life would be like if you couldn't picture things.
Say, somebody puts a lump of clay in front of you and wants you to sculpt what ever you want,
but you can't construct an image in your mind of what you want to make, so you can't sculpt.
Or maybe you're reading Harry Potter and the Sorcerer's Stone for the very first time,
but all of the descriptive scenes are just lost on you.
That first portrayal of Hogwarts, the skin of the Troll, or the look of the Quiditch Pitch – you can't picture
what the words are describing.
Or maybe your significant other calls you and you realize you don't know what they look like.
All of these things are symptoms of a neurological condition that has recently been described for
the very first time, it is now undergoing its first major study.
It's called Aphantasia – the inability to visualize things in your imagination.
It's almost the opposite of Pareidolia, a phenomenon we talked about a couple of weeks ago.
Pareidolia is just a trick that the mind plays on most of us when we see things that aren't there,
like a face in a pancake, or a tiny woman on Mars.
But Aphantasia is, like, the reverse, where a patient lacks the so-called "mind's eye."
Accounts of the condition go back more than 100 years, but it was only named and identified last month
by Dr. Adam Zeman, a neurologist at the University of Exeter, after media coverage of one of his studies
revealed that the phenomenon may be more common than anyone thought.
Recently, Zeman published a case study about a patient who awoke from heart surgery and found that he
no longer had the ability to picture things in his mind.
Discover Magazine then profiled Zeman's work, and soon he was contacted by nearly two dozen people
who said they had the same symptoms as the heart patient.
But most of them didn't know that there was anything different about them until they read about his research.
One subject, a 25 year old man from Ontario, was not only unable to picture things in his mind,
he can't conjure up smells, or sounds, or tastes, or any other sensations without experiencing them directly.
Another patient, a physician in Wales, has no visual memory and can't remember what any objects or people
look like until she sees them again.
Now, this is where I normally talk about what causes Aphantasia, but, of course, we don't know because it
was just identified a month ago.
The process of visualization is very complex because it involves most of the major areas of the brain,
so it's hard to pin down where a syndrome like this might start.
The act of seeing is processed by the Occipital lobe at the back of your head, for example, but whether or not
you actually perceive, recognize, or remember what you see depends on what's going on in a number of other
parts, including the Parietal and Temporal lobes.
Now that Zeman has enough subjects to study, he'll be analyzing their sensory skills, their life histories,
and even their dreams at night to see how their brains can tell them about people, places, and things
without being able to imagine them.
And this research is especially timely because we recently lost one of the most famous figures in
neurology and the study of perception.
Dr. Oliver Sacks died on August thirtieth of cancer, and we didn't want this week to pass without acknowledging
what he taught us about the science of the mind.
For fourty years, Sacks was a professor of neurology and Psychiatry at the Albert Einstein College of Medicine
in New York, and he spent the rest of his career in Columbia University.
But, unlike most other scientists we tell you about here, Sacks didn't do much laboratory research.
He was kicked out of the first lab he worked in in the 1960s because he kept losing samples and
breaking equipment.
So, instead, he began seeing patients, and there he discovered the type of research that would frame his
career: the case study.
He's remembered for writing books about people with rare and seemingly bizarre conditions,
like the man who mistook his wife for a hat, a book about a brilliant concert pianist who couldn't recognize
faces, including that of his own wife.
But, more often, he wrote about conditions as commonplace as migraines and color blindness.
He wrote about how people who can't hear experience the world in their own way,
and what life is like for a man who was born blind and suddenly becomes able to see.
And Sacks' investigations into conditions like Tourette's and Asperger's – syndromes that, at the time he wrote
about them were practically unknown – are now, thanks in part to his clear and sympathetic portrayals, better
understood, better diagnosed, and less stigmatized.
Essentially, Oliver Sacks did for the human brain what Carl Sagan did for space – he clarified misconceptions,
dispelled fears, and inspired wonder in all of us, and we will miss him.
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