Why Is A Face So Fast?

It takes a little more than three days to get from the earth to the moon.

It takes between 24 and 72 hours to digest a meal.

Your Google search is retrieved in about 200 milliseconds.

In only 100 milliseconds your brain recognizes a given lump of color and shape as a face.  70 seconds more and your brain will tell you whether know that face or not.

The brain is really good at recognizing faces.  The question is--why?

A view of the mind has emerged in recent years that suggests the brain is less like a meat computer and more like a meat app-store.  We aren't born with some tabula rasa of grey and white matter that we can program any old way we want.  Instead, our brain comes pre-installed with a number of modules for stuff like learning language, analyzing visual inputs, and yes--identifying faces--modules that are mostly hard-wired.  And really good at what they do.

So why is one of our modules devoted merely to identifying faces?

Humans are a perversely social creature.  We are more likely to live and die because of another person than because of any other factor.  Out there on the red-in-tooth-and-claw ancestral veldt I know that if I see Bert he'll buy me a pizza because he's cool.  But if I see Bobby I should be wary because Bobby likes hitting my head with rocks.

So it's important that our brains devote a huge amount of care to figuring out whether that lump of pink over there is a pig or OH MY GOD ITS BOBBY RUN GUYS RUN!

Sorry.  False alarm.  Not actually Bobby.  You see, sometimes the machinery of the mind goes wrong.  Usually what happens is that our face-finding module is set a little bit too high, so we like to find faces in places where faces just aren't.  This is called pareidolia and it is awesome.

All evidence to the contrary, this is not a smile.

And this is not Marlon Brando.

This is not actually a creeper.

And this is not a real dog.  Turns out it's just some pixels.  I KNOW.  I WAS FOOLED TOO.

Sometimes our face-finding module is set too low, or even turned off entirely.  Some of Oliver Sacks' most evocative writing is about people who suffer from a disorder called prosopagnosia, the inability to distinguish a face from the other mass of color and angle that splatters the visual field.  For them, a face isn't a face, it's just a vaguely face-shaped object.

The more we understand the brain, the more amazing even our simplest actions become.  So this Friday night as you and your friends indulge in your post-employment toasts, remember that merely to recognize that your friends are your friends takes thousands of years of careful evolution.

And watch out for Bobby.  I don't trust that guy.

If you're curious about the modularity of the mind, here's a fun video explaining it all.

Drink For The Muses

Monkeys do it.  College students do it.  Even gigantic elephants do it!  So why don't we do it?

Let's do it!  Let's get tipsy!

For our creativity, of course!  Lordly science has proved that a quaff of fermented potato juice can help the mind.

Recent research at the University of Chicago has started to explain why there may be a link between intoxication and creativity.  In what may be one of the simplest experimental set-ups I have ever read about, Andrew Jarsosz and his collaborators brought forty people into the lab to do a "Remote Associates Test", a common test of creative thinking.  Twenty of these lucky experimental subjects were given vodka.  The others were left quietly sober.  The tipsy people did better on the test of creativity than the dry ones.  Score one for the drunken artist!

Why should a drug that mildly poisons your brain also help you think?  Jarsosz et al suggest that drinking might help us get into what they call a divergent mode of thought, one which makes it easier to answer questions that require you to think creatively.

I am firmly to the coffee side of the coffee-alcohol-writer-continuum, so until Jarsosz and his friends prove that cracking open a beer can help blogs suddenly get popular, and novels suddenly become published, I am going to stick to my bean-based stimulant.

I read about this research on the excellent BPS Research Digest.  Boring name, fascinating blog.

Learning Today: May 24th 2011. The Kiddie-Diddling Tumor.

Everything a person is--every thought, feeling, idea and memory--is little more than an instance of brain activity. This is a radical and unsettling idea. My feeling of love is correlated with a particular set of neurons firing. My appreciation of great works of art is identical with activity in a particular region of my brain. I am a meat computer, weighing about three pounds, engorged with blood.

Though it may be unpalatable, there's a lot of evidence that the mind is nothing more than the brain. For instance, brain damage can often cause profound changes in human behavior. Take the case of the 40 year old schoolteacher who suddenly became an uncontrollable pedophile. His wife discovered him downloading child porn. He visited massage parlors. He even solicited sex from children.

But he also complained of horrible headaches. He urinated on himself and didn't care. He was unable to copy writing and drawings.

A day before he was supposed to go to prison on child molestation charges, he was put into an MRI. Doctors discovered a tumor in the right lobe of the orbifrontal cortex. When the tumor was removed, his sex addiction vanished.

But wait! Later, the man complained of headaches again and started to secretly collect porn. A second trip to the MRI revealed that the tumor had only be incompletely removed. The doctors out the remaining tumor, and the man was better again.

I heard about this story on the Philosophy Bites interview with David Eagleman. Check out the rest of the episode--it's a fascinating look into the intersection of ethics and neuroscience.