Sexy Neuroscience IV

Every culture and subculture has its own rituals of greeting and affection – handshakes, backslaps, fist-bumps, hugs and so on – but when it comes to erotic contact, cultural differences seem to melt away into something more primal: Touch that just feels good for its own sake.

In fact, a new study has confirmed that erogenous zones are remarkably similar and consistent among people from widely different cultures. This first “systematic survey of the magnitude of erotic sensations from various body parts” found that both men and women in Britain and in sub-Saharan Africa love be caressed on their lips, necks, ears and inner thighs; while pretty much no one is into kneecap-play (rule 34, though, folks). In short, erogenous zones seem to have a whole lot more to do with touch-sensitive nerves than they do with cultural conditioning.

And so, in the spirit of Part I, Part II and Part III of the Sexy Neuroscience series – which, incidentally, got this site banned from buying advertising on Google (yes, really) – The Connectome presents Sexy Neuroscience IV: Global Erogenous Zone Challenge!

As the journal Cortex reports, a team led by Bangor University’s Oliver Turnbull surveyed 800 people, mostly from Britain and sub-Saharan Africa. The investigators asked the participants which body parts (aside from genitalia) produced the most intense erotic sensations when others touched them. While the researchers did discover a few differences between male and female erogenous zones – for instance, men found it more arousing to be touched on the backs of their legs, and on their hands, than women did – most of the participants ranked a list of 41 body parts in similar erogenous order.

“Surprising!” say the researchers. “Why?” reply the rest of us.

I mean, most of us learn what our own bodies enjoy long before we clearly understand what sex and eroticism are. And plenty of us have defied cultural conventions when they didn’t line up with our own experiences of physical pleasure. I’d say it makes more sense that the whole concept of erogenous zones, and the culture surrounding them, both stem from common physical experiences; not the other way around.

But this study actually does reshuffle the erogenous-zone deck in one surprising way: It revises the sensory homunculus yet again. As I explained back in Part II, the sensory homunculus is a concept developed in the 1950s – by a bunch of men, which turns out to be a very significant part of the story.

The core concept is pretty simple: As you can see in this picture, touch sensations in various parts of our bodies are mapped onto a series of adjacent but differently sized brain areas; the larger the area, the more touch-sensitive a body part is. So far, so good. Except that until a few years ago, hardly anyone bothered to mention that this entire model was based solely on male brains. The cervical walls, the labia and the clitoris weren’t on it at all. And it took until 2011 for someone to come along and fix this.

So it makes sense that this latest erogenous-zone study has cleared up yet another longstanding myth about the sensory homunculus: That the bottoms of the feet are erogenous zones. Previous researchers had claimed this was true because a) lots of people think feet are sexy, and b) the sensory brain areas devoted to the bottoms of our feet lie right alongside the areas devoted to genitalia.

And although there’s no doubt that feet can be sexy – both visually and to the touch – and that they’re highly touch-sensitive and often ticklish, three fourths of the people surveyed in Britain and sub-Saharan Africa gave feet an erogenous touch rating of zero, right alongside kneecaps.

Turnbull and his team suspect that those previous researchers may have confused fetishistic touch with erogenous touch – two related but distinct phenomena. Those two feelings can – and often do – feed off one another; but there’s nothing to suggest that a caress on the foot feels inherently erotic in the same way that, say, a nip on the earlobe or a breath on the neck does. If anything, feet seem to serve as a clear example of culturally (and/or experientially) conditioned eroticism.

So where does this leave us as far as sensory homunculi and erogenous zones? Well, results like this reinforce the importance of communicating with your partner(s) instead of just following sexual ideas you’ve picked up from others. Erogenous zones may be strikingly similar across genders and cultures, but no two of us are exactly alike: Some find erotic what others find ticklish or painful – and some find tickling and pain erotic. The only way to find out is to ask. Who knows – you might even find someone who enjoys kneecap foreplay.


“Learning How Brains Learn” — Podcast 9: Jeff Hawkins

On Episode 9 of the Connectome podcast, I’m joined by Jeff Hawkins, a computer engineer and neuroscience geek who’s obsessed with understanding how the brain learns.

Jeff is the inventor of the Palm Pilot and the founder of Palm Computing – as well as another computing company called Handspring – but in addition to his computer skills, he’s also been fascinated by neuroscience since the late 70s. Today, his company Numenta designs a range of software known as Grok, which learns and thinks like a living brain.

Jeff’s superb book On Intelligence lays out his theory in detail, and he also runs over the basics in this podcast. If you’re interested in digging further, here’s a link to Numenta’s technical documentation of how their software works, and here’s a page with lots of videos of Jeff’s other media appearances.

As you’ll hear on this podcast, though, Jeff’s curiosity extends far beyond software engineering, and explores subjects from space exploration to computing’s future to the nature of intelligence itself. Listen in, and you may find that your own curiosity gets sparked, too.

Click here to play or download:

Enjoy, and feel free to email us questions and suggestions for next time!

(Produced by Devin O’Neill at The Armageddon Club)


A Secret Society of Cells Runs Your Brain

In this article for Scientific American, I talk about a new study that discovered some surprising things about a class of brain cells that’ve long been assumed to sit silently. Oligodendrocytes aren’t neurons – they’re support cells; and for a long time, their exact behavior was a mystery. Now, researchers are discovering that they take a much more active role in brain function than anyone expected.

Bergles was intrigued by the persistent cycling of these progenitors, so he and his team determined to study the behavior of individual oligodendrocyte progenitors in living brains. The researchers set to work engineering mice in which just these cells make a green fluorescent protein, aiming to track their behavior on shorter timescales than ever before. What they discovered surprised them as much as anyone.

Read more of my article at Scientific American.

Oliver Sacks

“Hallucination & Imagination” — Podcast 8: Oliver Sacks

On Episode 8 of the Connectome podcast, I talk with Oliver Sacks, renowned neuroscientist and author of such books as The Man Who Mistook His Wife for a Hat, Musicophilia and Hallucinations. In particular, Sacks joins us to talk about some patients of his who’ve been hallucinating strange varieties of musical notation.

But musical hallucinations are only the beginning – Sacks also shares his insights on dreams, hallucinogenic drugs, selfhood, and plenty of other phenomena that make subjective experience so mysterious. Whether you’re new to Dr. Sacks’ work or a lifelong fan of his writing, this interview raises some consciousness-related questions that you may never have considered before.

Click here to play or download:

Enjoy, and feel free to email us questions and suggestions for next time!

(Produced by Devin O’Neill at The Armageddon Club)


What’s Individuality, and Where Does It Come From?

In this article for Scientific American, I dig into one of mankind’s oldest and deepest questions: What’s that special something that makes you different from me? Where does it come from, an how early can we find it? A new German study may have found some surprising answers to these age-old mysteries.

Three months later, the researchers reexamined the mice, and found not only that their brains had grown more and more individually distinct over time, but that the brains of the mice with the highest roaming entropy had grown and changed the most of all. Specifically, these mice sprouted far more new nerve cells in their hippocampus – a brain region crucial for forming and retrieving memories in mice and in humans – than less adventurous mice did.

Read more of my article at Scientific American.


Tomorrow’s Anti-Anxiety Drug Is… Tylenol?

In this article for Scientific American, I talk about a new study that may have found an unusual use for a popular pain drug. Could Tylenol – also known by the drug name acetaminophen – really be the anti-anxiety drug of the future? If so, how would that work? Why would it work? And are high doses of Tylenol safe for patients’ bodies?

The brain scans were clear: The ACCs of people who’d been taking acetaminophen didn’t respond nearly as strongly to feelings of social rejection as the ACCs of people who’d been on a placebo. The drug was buffering feelings of social pain – not by muting people’s emotions or fears, but by somehow toning down the brain’s central sense that anything was wrong or at risk in those particular scenarios.

Read more of my article at Scientific American.

Neurologist Dr. Oliver Sacks Speaks At Columbia University

Oliver Sacks’ Tales of Musical Hallucinations

In this article for Scientific American, I present my personal interview with renowned neuroscientist and author Oliver Sacks. Dr. Sacks’ latest book, Hallucinations, deals with his patients’ strange experiences with all sorts of visual and auditory phenomena – but he’s also here to discuss a recent paper in which he focuses on hallucinations of the musical kind.

One of Sacks’ patients, for example, found that the embroidered border of his bathmat tended to transform into elaborate staves and clefs of music. He noticed a similar transformation in the text of his newspaper as he tried to read it, so one day he set his newspaper on his music stand and tried to play what he saw. The only problem, Sacks says, is that “the notation turned into different music every few seconds, and it kept altering.” The patient, who also happens to be a professor of Sanskrit, discovered another odd twist when he studied his hallucinated notation more closely: The musical notes kept taking the shapes of letters in Sanskrit’s traditional Devanagari alphabet.

Read the rest of my article at Scientific American.

Roundtable Round 2

“Engineering a Mind (Part 2)” — Podcast 7: David Saintloth and Wai Tsang

On Episode 7 of the Connectome podcast, we rejoin our two-part roundtable discussion on the nature of intelligence, on the differences between biological and artificial intelligence, and on the ways in which the idea of digital intelligence can inform our understanding of how our own minds work. (Here’s the link to Part 1 of this discussion.)

Joining us, once again, are David Saintloth, a software engineer who’s working on programs that use a technique he calls “action-oriented workflow” to proactively learn and adapt as they find connections between data patterns; and Wai H. Tsang, a thinker, lecturer, futurist and software programmer who champions what he calls the “fractal brain theory:” the idea that everything the brain does can be described in terms of a single type of fractal pattern.

As before, we’re discussing a lot of ideas developed by thinkers like Jeff Hawkins and Ray Kurzweil, and our goal here is simply to compare notes on each of our perspectives, look for ways in which computer science can inform neuroscience (and vice versa), and hash out some general outlines of a shared descriptive vocabulary for comparing intelligence across digital and biological platforms. So feel free to jump into the comments and share your thoughts, criticisms and insights.

Who knows – your idea might be the spark that launches this discussion in a whole new direction.

Click here to play or download:

Enjoy, and feel free to email us questions and suggestions for next time!

(Produced by Devin O’Neill at The Armageddon Club)


Three Big Doubts About Brain-Mapping Efforts

Neuroscience research has come a hell of a long way since the days of scalpels and electrodes.

While some research teams are exploring the molecular machinery that churns at the hearts of nerve cells, others are working to assemble wiring diagrams for whole regions of the human brain. Just as biological science never looked the same once Watson and Crick explained the structure of DNA, neuroscience is transforming into a field filled with laser-controlled neurons, programmable stem cells and micro-scale brain scans.

Beyond all this excitement, though, looms a far more vast and ambitious goal – one whose scale and complexity exceed even the mapping of the human genome. Over the past several years, a growing group of scientists have been fighting for the idea that we can (and should) produce, within our lifetimes, a digital map of every function of every one of the trillions of synaptic connections in a human brain: A complete human connectome. Teams around the world, such as the minds behind the Human Connectome Project, are already working hard toward this goal, often freely sharing the data they discover along the way.

The Human Connectome Project's first huge data sets are already freely available to scientists around the world.

The Human Connectome Project’s first huge data sets are already freely available to scientists around the world.

Meanwhile, this February, the White House announced the launch of the Brain Initiative, a decade-spanning effort to build a “Brain Activity Map” or BAM – a simulation, in other words, of all the activity in a human brain, from the cellular level on up. The project’s launch budget is $100 million, and some scientists expect that costs will soar into the billions before it starts cranking out useful data.

Unsurprisingly, this has stirred up a hurricane of press coverage – not all of it positive. While some advocates of the BAM project promise that it’ll unleash a wealth of new cures for neurological and psychological diseases, opponents argue that even billions of dollars and years of research won’t be enough to decode the brain’s workings on such a comprehensive scale – especially if, as some anti-BAM pundits say, we’re still a long way from knowing how the brain even encodes information at all.

I’ve put together a little write-up on three of the biggest BAM bones of contention. Though I can’t cover the whole issue in detail with just one article, these summaries should help you score some points in a BAM-related argument – and give you some fuel for your own exploration. So let’s see what (some of) this fuss is all about.

Doubt #1: Do we have the computing power to simulate a whole human brain?

Nvidia's "Titan" supercomputer, which (as of April 2013) holds the world speed record of 20 petaflops.

Nvidia’s “Titan” supercomputer, which (as of April 2013) holds the world speed record of 20 petaflops.

The BAM invites a lot of comparisons – both positive and negative – with the Human Genome Project of the 1990s. Both are long-term projects, both are hugely expensive, and both involve number-crunching and analysis on scales that demand tight cooperation from top scientists and universities around the globe.

But whereas the Human Genome Project set out to map somewhere in the neighborhood of 20,000 to 25,000 genes, all of them constructed from the same four nucleotide molecules, a map of the human connectome would have to incorporate the behavior of at least 84 billion neurons and as many as 150 trillion synapses – all communicating via a dizzying menagerie of messenger chemicals, not to mention physically reshaping themselves as a brain grows and learns.

Estimates vary widely on the question of how much computing power it’ll take to simulate a whole human brain, but even the most optimistic experts believe it’ll take a computer capable of performing at least 1 quintillion (that’s 1,000,000,000,000,000,000) floating point operations per second (1 exaflop). By comparison, your average home computer processor maxes out around 7 million flops (7 gigaflops), a fast graphics card can reach over 300 million flops (300 gigaflops), and the latest supercomputer processors clock in at a little over 20 quadrillion flops (20 petaflops). So, on that front at least, our resources are rapidly approaching the goal – scientists at Intel predict that we’ll be computing in exaflops before this decade is over.

But raw computing power is only one part of the equation. In the most basic sense, even the most advanced computer is just a machine that follows instructions – so even after we’ve built our exaflopping supercomputer, we’ll still need to know what instructions to give it.

[UPDATE! – May 8, 2013]

Carlos Brody, a neuroscientist at Princeton’s Brodylab, has added a clarification of his own to this section. Here’s what he has to say:

“I think Doubt #1 is about the European Human Brain project, not about the U.S.-based BRAIN Initiative. The way I’ve understood it, the Europeans, with their billion-euro Human Brain project, are trying to simulate every neuron in a brain. In contrast, the U.S.-based BRAIN Initiative/BAM is about developing the technology to allow us to record the activity of every neuron in a brain. Not simulate, but measure what’s there. It’s a big difference, because in order to simulate you have to build in a lot of knowledge we don’t yet have (i.e., put in a giant truckload of untested assumptions). That is largely why many people think the simulation effort is pointless, there’s so many untested assumptions going in that what you end up with may bear little to no relation to an actual brain. The goal of measuring the activity, as in BAM, is to gain that knowledge we don’t yet have.”

Thanks, Dr. Brody, for your insight into that distinction!


Doubt #2: Do we know enough about brains to know what we’re attempting?

All human DNA is made up of just four "bases," known as nucleotides: Adenine, cytosine, guanine and thymine.

The Human Genome Project set out to map the position – but not necessarily the function – of each nucleotide in all 23 human chromosomes.

Contrary to oft-repeated belief, the Human Genome Project’s goal was never to decode the function of every gene in human DNA – it was to map (sequence) the order and position of every nucleotide molecule in all 23 human chromosomes.

Scientists have only begun to make a dent in decoding the 20,000+ genes whose positions the Human Genome Project mapped. Even today, leading researchers are still debating how many genes the human genome actually contains – let alone what functions most of those genes encode. And that’s more than half a century after Watson and Crick described, in detail, the way that DNA encodes recipes for manufacturing the molecules that make up our bodies.

When it comes to the brain, on the other hand, the world’s top neuroscientists are still puzzling over the question of how neural activity encodes information at all. We’re using computers to construct videos of entire visual scenes based on the brain activity of people watching them – but that’s only after recording brain scans of dozens of patients as they watched hundreds of videos, then telling a computer to reverse the process and assemble a video that matches the brain activity patterns it sees.

This is no small achievement, to be sure – but even so, it’s sorta like learning to recognize whether the letters in a book are Chinese, Japanese or Arabic (assuming you don’t read any of those languages). You might be able to match a new book with the country that produced it, and maybe even recognize whether it’s, say, a novel or a dictionary. But none of that tells you much of anything about what a specific line on the page actually says.

This is one of the trickiest questions for BAM advocates to answer – and the answers tend to come in two main flavors. One response is that the fastest way to crack the neural code is to try simulating it digitally – just as the fastest way to learn a new language is to start writing and speaking it yourself. Another response is that a base-level understanding of the code may not be necessary for a rich and detailed understanding of how a brain works. Scientists have already mapped the functions and interactions of all 302 neurons in the nervous system of the tiny roundworm known as C. elegans. Even without knowing exactly how these neurons encode information, we’ve still built up a precise understanding of how each of them influences other neurons and muscle cells throughout the worm’s body.

Although the human brain’s 84 billion neurons aren’t exactly a small step up from C. elegans‘s 302, it stands to reason that if we do develop software and hardware that can simulate all our neurons’ interactions, we’ll be in a much better position to pinpoint specific processes and problems down at the cellular level.

Doubt #3: Will an epic mapping project produce useful results?

Just as no two humans share exactly the same set of genes, no two human brains are wired in exactly the same way.

Just as no two humans share exactly the same set of genes, no two human brains are wired in exactly the same way.

BAM critics like to draw a third unflattering parallel between the BAM project and the Human Genome Project: As the Human Genome Project approached completion, its White House advocates predicted that a sequenced human genome would lead to cures for diseases like cancer and Alzheimer’s, along with “a complete transformation in therapeutic medicine.” But more than a decade after the Project’s completion, very few of those medical benefits have actually materialized.

What has resulted from the Human Genome Project is a vast storehouse of data on how human DNA differs from that of other animals – and from one human being to another. This means that when we consider the outcome of the BAM, it’s important to keep our sights not on vague and grandiose promises about cures for poorly understood problems, but on what we can be sure would come out of a successful BAM project: A more detailed, accurate and integrated understanding of the human brain’s workings than we’ve ever had before.

If one thing about the BAM is certain, it’s that the project’s news coverage – and the intensity of the debates that coverage stirs up – will increase in step with the Brain Initiative’s funding demands and timing estimates. As I said at the beginning of this article, a few thousand words aren’t nearly enough to cover all the ink that’s already been spilled in the earliest stages of this debate – so jump into the comments and chime in with your own opinions, doubts, speculations and questions. Because in the end, the only way to resolve an argument is to talk it out.

Roundtable Round 1

“Engineering a Mind (Part 1)” — Podcast 6: David Saintloth and Wai Tsang

Episode 6 of the Connectome podcast brings together two guests who are obsessed with understanding how intelligence and thinking work – not by studying patients in MRI scanners, but by working to develop software that recognizes patterns and connections in the same way a brain does.

Our guests are David Saintloth, a software engineer who’s working on programs that use a technique he calls “action-oriented workflow” to proactively learn and adapt as they find connections between data patterns; and Wai H. Tsang, a thinker, lecturer, futurist and software programmer who champions what he calls the “fractal brain theory:” the idea that everything the brain does can be described in terms of a single type of fractal pattern.

To be fair, many of the ideas we discuss here – or, at least, very similar ones – have already been developed in detail by theorists like Jeff Hawkins and Ray Kurzweil. So our goal here is simply to share and compare what we’ve each learned so far, and bring you in on our conversation. We’re looking forward to dialoguing and debating with you in the comments.

Who knows – maybe you’ve noticed something all three of us are totally missing.

Click here to play or download:

Enjoy, and feel free to email us questions and suggestions for next time!

(Produced by Devin O’Neill at The Armageddon Club)

Powered by WordPress | Designed by: free Drupal themes | Thanks to hostgator coupon and cheap hosting
Social links powered by Ecreative Internet Marketing