The Neuroscientist Will See You Now

Neuroscience Explained
Image: Daniele Oberti, Creative Commons.

Unintentionally, I think I might have started something. After my previous post, in which I discuss a weird brain moment my sister had (one of many, I assure you…) it appears that several of you have taken this as a cue to inundate me with your strange brain goings-on, followed by something along the lines of ‘explain, please?!’ Take this one, which my dad recounted to me in an email:

Now, I’ll tell you something I’ve discovered as a train spotter (I know that’s what you call me!) – very strange but like an odd sort of dyslexia.
So, an engine with number 37321 goes past.
I say to myself in my head, ‘that’s engine no. 37231.
I write down engine no. 37321 how do you explain that?! I see it correctly, my brain notes it incorrectly, but my eyes transpose it onto paper in the correct order that I saw it. How can that be?

This certainly intrigued me. It’s a great example of how the brain is always tinkering ‘behind the scenes’, carefully editing and filtering information in that brief time between your brain receiving information and you consciously perceiving it.
Remember when brain-training games first appeared as a new craze? If yes, you’ve probably encountered the sort of test where you’re presented with a series of words written in different colours, and your simple task is to read the words aloud.
TRAIN, BAKERY, HAMSTER
Pretty straight forward, but when you see GREEN written in red, chances are unless you’re paying close attention, you’ll blurt out ‘red’ instead. This is something strange called the Stroop Interference, and it shows just how powerful the influence of vision – our primary sense – is.

And my educated guess is that something similar was going on with my confused dad. Despite the incorrect number that he’d consciously perceived (the colour name written) his brain overrode this and replicated the image it had already seen and unconsciously registered: the correct number (in our other e.g, the colour the word was written in).
With this case, I suspect – and I may be wrong here – that the focus was largely on the shape that the numbers 37321 made, rather than what the numbers actually were, especially since he was physically replicating it by writing them down. The visual override here is that the brain was simply reproducing on paper the shape ‘37321‘ it has just seen, bypassing the conscious numerical though (and subtly different shape) of ‘37231‘.

But, Stroop Trainspotting Interference aside, I would just like to emphatically reiterate this: I am not a doctor. Hell, I’m not even a medical student! I haven’t even graduated and received my extortionately expensive piece of paper saying ‘congratulations, you know lots of temporarily true facts about brains.’ (For £27000 I am wholeheartedly expecting the most gosh-darned fancy piece of paper I have ever seen in my life. They better have started working on it already…) And even if I were any of these things, like every other human, I am a mountain of ignorance: the things I don’t know will always, always outweigh the things I think I know.

So, while it’s not my business to know everything, I very much make it my ponderous business to be fascinated by the strangeness of the brain. So keep the tales of neuro-quirks coming, the weirder the better; if only because, like some neuro-equivalent of Sherlock Holmes, they intrigue me and tickle my grey matter. I can’t give you a definitive answer, but I can certainly share my best thoughts.*
So…next?!

*Hopefully this should be obvious, but while this is all fun, if you think you might genuinely have a medical problem please, please go and consult a doctor.

Seeing Is (Not) Believing: The Mystery of the Chequered Blanket

Neuroscience Explained

Image: Pierre-Alexandre Garneau, Creative Commons

To anyone else, conversations between my sister Katy and I are probably strange to say the least. I’ll let you be the judge of that. However, one thing I can say is that our exchanges rarely give me pause for neuroscientific thought. Until now. What follows is a very condensed transcript of an extremely confused 10 minutes of heated typing over Facebook. What was the cause of such a frenzy? Well, since you ask, I’ll tell you: blankets.

(At this point, to give some context, I should probably point out that we had been talking about packing for an upcoming camping trip and don’t usually spend our time debating textiles.)

Katy: What about that chequered blanket you had on your chair in your old room? Have you disowned it, or did I imagine its existence.
Rebecca: ‘Chequered blanket on my chair’? Um I did have a pink one, I think? I can’t for the life of me remember a chequered one. What colour are these chequers? Are you sure we’re talking about a real blanket that actually exists, because I’m confused.
K: Do you have the blanket I was referring to?
R: …In case I hadn’t made it clear already, I DO NOT KNOW OF THIS CHEQUERED BLANKET OF WHICH YOU SPEAK!
K: I swear it exists!
R: What colour?! I’m concerned now that somehow my brain has managed to completely wipe a blanket I’ve apparently had in my room for years.
K: Green?
R: Green?!
K: You’ve not had it for years, you said you bought it in Hampstead. With its matching pillow?
R: Ohhhhh. That one. No, it’s brown you silly. Only the pillow was green/chequered (ish) – they don’t match…the chair under the blanket was green though?
K: Same thing. It had some green on it.

(Later….)

K: OOOHH, I remember now!
R:
K: Yeah, it was brown and the pillow was green chequered. My brain is smushing things together!
R: Bit weird.
K: Yeah, but you could’ve worked it out, I obviously wasn’t talking about your pink blanket.
R: Sorry, I’ll be sure to do a proper census of all my blankets in future. How foolish of me.

While the rest of my aching brain was lamenting 10 pointlessly fabric-related minutes of my life I was never going to get back, the neuroscientist in the corner was appreciating what a perfect example this was of the everyday lies that our brains feed us. Having seen these objects on several occasions (and even rested her sleepy little head on the pillow) how had my sister taken this:

and this:

and ‘smushed’ them together to fabricate some sort of hybrid blanket, totally convinced that it existed? Somehow, her brain had taken background details in memories which it deemed to be minor and simply glossed over them. In her words: ‘same thing. It had some green on it.’

A question like ‘but how do we know what’s real?’ sounds like it belongs in Inception or to that stage of drunkenness where certain people are prone to turn into philosophers. However, when you stop and think about it, the (equally Inception-worthy) answer is: ‘we don’t.’ We rely on our brains to perceive the world around us, and that’s what we have to accept as ‘reality’.

The trouble is that ‘reality’ isn’t always real. The universe’s most complex organ is surprisingly easy to fool. And when it’s not being fooled, chances are it’s either holding select things back or just downright making them up as it goes along! (The chequered blanket debacle being a case in point.)

Now, you might be thinking that mistaking a blanket for a cushion is a reasonable mistake. But what about two completely different people standing right in front of you: anyone could tell the difference, right? In one well-known study, which sounds more like the set-up of a prank show or a comedy sketch, people were stopped at random in a courtyard and asked for directions. Little did the unsuspecting subjects know that they were in fact talking to a researcher and were about to be part of an experiment. Whilst the person was attempting to give the researcher directions, ‘workmen’ carrying a door inconsiderately walked between the two people. During this rude interruption, whilst briefly obscured from the subject’s sight, the researcher was replaced by another who had been sneakily hiding behind the door whilst it was carried. Once the door was gone, a completely different person was standing in front of the subject: ta-da! Or so you might think, but astoundingly, the majority of the subjects didn’t even notice the change! Their brains simply weren’t seeing everything they were looking at. Unconvinced? Why not grab some friends, a door and some unsuspecting members of the public.

And here’s just a few more examples of how unsettlingly easy it is to trick your brain into feeding you an alternative ‘reality’.

The McGurk Effect (you can try this one out on yourself!)

Defying the boundaries of the body. The Rubber Hand Illusion

Altered Vision (To the left, to the left…)

As if the considerably deep question of ‘but how do we know what’s real?’ wasn’t enough to be going on with, the differences between the sensory information our individual brains receive and how they each decide to display this to us raise countless other questions. For example: how can we rely on court-case witnesses – even ones with whole-hearted, honest intentions – when countless tests have shown how fallible our sensory memory can be? Just because you believe, even know something to be true, doesn’t mean it is. This should also make us question the stigma attached to symptoms of neurological conditions. Take Charles Bonnet syndrome for instance, where patients losing their sight will experience visual hallucinations, but are fully aware that what they are seeing is not really there. While it’s actually thought to be quite common and affect around 1 in 10 of people suffering from eye diseases or deteriorating vision, it’s a largely underdiagnosed condition. Which is unsurprising, since our collective idea of sanity generally involves people being able to see the same things that we see. The more we learn about perception and the brain, the more bizarre this idea seems, because if there’s any conclusion we can be certain of in this world, it’s that – quite frankly – all brains are hair-raisingly weird. No matter how tiny the differences, my brain’s ‘reality’ is certainly different to your brain’s ‘reality’. All I know is that it’s real.

Isn’t it?

 

Brief Plug: Just in case you missed it, here’s a link to some ramblings I had fun writing for the folks over at Shot of Science called Test Tubes at Dawn: The Duelling Scientists (it is indeed as silly as it sounds…) Read if you so wish, or just carry on as you are. That’s fine. It’s up to you, really.