I’m back!

Hello, blog. It’s been a while. So many things have happened. I am now a doctor!

Let me tell you about how this happened. For starters, I gave an exit talk.


Then I gathered the signatures of all four committee members and I submitted my dissertation.

Screenshot from 2015-08-11 11:26:02

Finally, I got a lollipop. I could hardly believe it. I did it. I fooled them all.


[Not pictured: I got a “dissertation muffin top,” which is what I think we should call all those studies you started with your advisor during more optimistic times, that don’t fit neatly into the muffin cup of your thesis, but instead spill over into the rest of your life indefinitely. Currently responding to reviewers on a paper, for which I collected data in my FIRST YEAR of graduate school. Let that sink in.]

My first order of business as a doctor was, of course, to go to Burning Man.


It was a dusty one.


I came back, dusted myself off, and started a new job!


Which brings me to the reason for my return to the blogosphere. It’s been a nice summer-long hiatus during which all of my writing efforts were poured into “real science.” I figured I’d start writing for the internet again sometime, and that time is now. I have new goals, a new environment, a new perspective.

I’m a Thinking Matters fellow at Stanford (for real! It’s a kind of demi-professor post, so no, Mom, I’m not a real professor), which means I’ve been placed on three teams (one each for the fall, winter, and spring quarters of the school year) to teach a special set of classes designed for freshmen. They show up, having survived whatever insane gauntlet of courses and extracurriculars got them here in the first place, and they are required to take at least one of these courses to help them transition, pick up collegiate study skills, and level up on their critical thinking and rhetorical prowess. Given that these students will have a range of preparation from their high school years, I am excited to be a part of this great equalizer.

More selfishly, the curriculum and team dynamic of my first course, The Science of Mythbusters, are nothing short of perfect for me. I get to indulge all of the vendettas I’ve been fermenting for the last six years, by dropping truth bombs about how we do science onto the next generation of world leaders. That’s right, someone gave this angry woman a platform. Oh sure, I spend 4 hours a day commuting, sometimes crossing the bog of eternal stench that is the south bay on a very slow bus. And sure, I’m still getting used to some things (like how here, if a projector doesn’t work, it’s expected that something can be done about it–I guess that’s how money works). But the important thing is: I don’t hate my job.

In fact I really really really like my job.

I like my job so much that my ideas are starting to come back. I’ve been mining old notebooks for writing topics, reveling in my continued university-affiliated PubMed access, and scribbling down anecdotes that tumble from the mouths of some of the most ridiculously enthusiastic and engaged academics I’ve yet met. I’m still pretty sure that my still being in a university means I can’t access press releases on embargoed studies (holler at me if you think different, EurekAlert!), but then, how many times have I heard from my science writing idols that it’s lame to only cover things because they’re new? Challenge accepted.

Look for a new post soon–I wouldn’t be writing if I didn’t already have a special paper in mind. I’ve got three years in this here writing incubator. The work is fun, the people are nice, and the air here is rich with inspiration.

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Lately: Fresh writings!

It’s been a good month for writing! Dissertation AND extracurricular, I’m happy to say. I’m almost a doctor!

But first, we’ve got some important science to talk about. After hatching the idea (ha) at Zoo Bar, a grubby box across the street from the National Zoo in Washington, DC, my favorite story of all time has finally become an actual piece of writing on the internet. I emailed the zoo’s information line and soon found myself Skyping with Chris Crowe, whose last name by the way is Crowe. This bird man had the sweetest, weirdest story I’d ever heard, and it was incredibly fun to spin the gold he was giving me in the interview. Walnut the Crane who fell in love with her zookeeper trended for like a whole Saturday on the Verge until some Game of Thrones episodes leaked and wrecked her lead. It was a good day.

Still high off crane love, I went up to the Lawrence Hall of Science to cover their STEM Career Showcase for Students with Disabilities for the Berkeley Science Review blog. There, I got to meet Dr. Josh Miele, whose work I really admire. I first learned about him while researching the Sonic Eye for last fall’s issue of the BSR. He works on engineering smarter assistive devices for blind people, a field he got into out of plain necessity as he worked on his research in physics. Finding workarounds, and finding a community of people who knows workarounds too, is key to carving out a career when you have a disability. At the event, I talked with student attendees, panelists, and staffers at the Hall. The panelists shared so much of their passion and creativity with attendees who had faced similar challenges. I left the event excited about the work Miele and others are doing to make STEM careers more universally accessible.

Finally, the Spring 2015 issue of the Berkeley Science Review Magazine is out! It’s always nice to see in print: the design team does some truly stunning work, and I want to frame every page. For my last semester here as a grad student, I wrote a brief on how some people’s brains resist the buildup of plaques thought to be a marker of Alzheimer’s Disease. The piece is called Staying Sharp, and again I got to interview really nice people working on interesting stuff: Bill Jagust and Jeremy Elman. They were part of a team in Jagust’s lab whose results provide fresh evidence that the brain is plastic across the lifespah. Alzheimer’s Disease affects so many people, and as humans live longer, soon there won’t be so many young people to take care of the old people. Some days it terrifies me so much I think we should just dump the whole NIH budget into it. Anyway, enjoy the read!

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Brains and blinky lights: an update

An art installation at the Exploratorium’s Cognitive Technologies exhibit

Wow, post-SfN fatigue really took its toll on my posting frequency, eh? But I would like to draw your attention to a few pieces I’ve been working on that came out elsewhere recently, and share a few photos I took at the Exploratorium last week.

Here’s my labmate Alit trying out the brain-machine interface at the Exploratorium.

Just today, my coverage of the Exploratorium’s new exhibit went live. My dear pal Natalia invited me to cover it and I’m so glad she did. I highly recommend going to check it out. Invite me if you go, because there were a few things I didn’t get to try out because of all the people milling around. The exhibit contains the flashiest of flashies, and yet, I think its greatest contribution lies in its willingness to allow people to experience the limitations of what brain decoding and other technologies can do. Go put on an EEG headset, and when it tells you you’re relaxed, or excited, or whatever, ask yourself if you think that’s true. Then go tell your anti-vaccine relatives what you learned about the difference between being a single datapoint and really synthesizing a literature. Go ahead, I’ll wait.

Dry electrodes stud a repurposed scuba cap to drive a brain-machine interface. DIY at its finest!

Dry electrodes stud a repurposed scuba cap to drive a brain-machine interface. DIY at its finest!

A bit ago, I wrote about my favorite poster at SfN, by former Berkeley grad student Taraz Lee. Check it out here. Taraz studies choking under pressure, and he uses both non-invasive brain imaging techniques and mad scientist brain-zapping techniques to get a handle on what’s going on. Truth be told, I’m more excited about the preliminary brain-zapping results he told me about, although I covered his imaging work here. Can’t wait to see where he goes with it!

Oh no, it's....THE CLAWWW!!!

Oh no, it’s….THE CLAWWW!!!

Finally, the Helen Wills Neuroscience Institute, my home, my science family, got a freshly revamped website! They’ve focused on compiling their very own news section, pulling coverage from around the interwebs, but also recruited me and other grad students to do some ($$$PAID$$$) in-house public relations. It’s been a long time coming, but the first of three pieces I wrote for them, singing the praises of our legitimately awesome Brain Imaging Center, is here. In writing these pieces, I’ve had so much fun interviewing lots of Berkeley people, some I knew, most I did not. This one, the BIC writeup, is close to my heart because I’ve always known that the BIC was special for the level of independence and education it gives its users, and this gave me a chance to hear the real backstory.

A schematic from the Cog Tech exhibit

A schematic from the Cog Tech exhibit

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Four impossible things before breakfast: Amy Bastian’s empathic logic

I had wanted to write up Amy Bastian‘s excellent 8:30 am talk from SfN, and finally it is happening. That’s right, my hangover and I were front and center so you didn’t have to be. I’m looking at you, #sfnbanter. You’re welcome. A couple of weeks late.

This talk was excellent not least of all because Bastian understood that at 8:30 am, no one was functioning quite properly yet. There was going to have to be a lot of hand-holding, and a lot of balloon walkers. Bastian’s talks are always clear and engaging, and this one was particularly merciful to boot. Bastian walked us gently through four of her papers (instead of a thousand like some other speakers who shall remain nameless), and that is why I retained enough to write you all this (let’s be honest) listicle.

I will start with a point she finished with, which is that many injuries like stroke, trauma, or even surgeries that remove up to half of the brain to stop epilepsy, cannot be treated with drugs, operations, or even fancy stuff like lasers or tampering with DNA. All of which is to say that, and I’m paraphrasing Bastian here, we must engage in some rational way with the patients’ motor processes. We must play their game to figure out how they work, get them to give up their secrets. If you think you’ve heard me gush about this before, it’s because you have. I am a sucker for a paper that reads like a Roadrunner vs. Coyote storyline. That, and I once had a total meltdown upon breaking a piece of equipment that was worth more than I made in a year, so no, I don’t like using fancy equipment.

But physical therapists like Bastian, in particular, wow me with this incredible empathy. Bastian says, it’s easy for friends and family to shout at their injured loved one, “you can do it!” or “just take a bigger step!” Indeed, this is how we encourage babies. But people aren’t babies–their brains are not the doughy, plastic things that babies’ are. They are a loaf of bread with a jagged slice taken out of it, and you need to make a learn-to-walk-again sandwich.

So in this case–and this is what I love about this research–the rational, logical thing to do is to accept what is and work with it. You can’t make someone heal by telling them what to do, and there are no guarantees they’ll heal fully or only partly. This letting go of control is probably the hardest thing asked of scientists, Type A monsters that they are. To promote healing, often it is the brain’s implicit, rather than explicit, learning mechanisms that must take the wheel. You don’t learn to do a cartwheel by poring over an instruction manual, and you don’t learn to walk again by having your mom shout “Walk, baby, walk!” at you as you struggle to rise, unfortunately. You have to play by the rules of whatever brain part is still working, and these might be radically different from what you are used to, as a person who used to have a much wider repertoire of movement capabilities.

Bastian’s work is focused on figuring out what those rules are and playing by them. During her talk, I saw a little girl with half a brain walk around like any other kid, like it was no big deal. She should be paralyzed on one side of her body and who knows what else. But if you’re wily and you listen, you might think up the right question to ask the motor system, and it might say, ok, you got me. Here are my secrets. She can walk if you do x, y, and z, and then bam: walking girl.

Here are some crazy secrets of the motor system I learned very early one morning a couple of weeks ago.

1. Think of your brain as your 16-year-old self, learning to drive a car, except instead of a car it’s your body. At 16, you figured out how to drive a car, and as a baby, your brain figured out how to drive your body. The cerebellum creates a match between your brain and your body, even when your body changes. Depending what parts of the cerebellum are damaged, you might think parts of your body have more or less inertia, and therefore think they’re heavier or lighter than they really are. Bastian’s team modeled each patient’s “too light/too heavy” body/brain mismatch and corrected for it using robots that hold the arm as it moves. With their arms guided by the robots, the patients’ biases were corrected and their movements became more normal. These models could also be run in reverse: they could program them into the robot arms, strap in a healthy person, and get the healthy person’s arm to move as though they had a bias like that of the cerebellar damage patients. This is promising–in the future, perhaps prosthetic devices could capitalize on these models to provide corrective force to patients’ movements.

[Bhanpuri, Okamura, & Bastian 2014]

2. We rely on predictive control–that is, the ability to predict the consequences of our actions. When we make a mistake, we use that information to update our predictions. But patients with cerebellar damage can’t. This could be for two reasons: It’s possible that the cerebellum generates quick-fix adjustments to movements as we make them. If this is so, patients’ poor ability to adjust is because they can’t come up with these motor adjustments. It’s also possible that it deals with the senses more than movement, generating predictions about what sensory information to expect. If this is so, patients lack the proper predictive power to select the right motor plan for the sensory feedback they’re trying to get (say, shooting a ball into a hoop or bringing the coffee mug to their mouth). Well, it turns out we update our sensory predictions. They figured this out by having patients and controls make “shooting” and “pointing” movements. In shooting movements, they had to point straight to a target while their feedback was manipulated, eliminating the possibility of correcting for the manipulation on the way to the target. In pointing, they were allowed to correct on the way. Patients were impaired at both, meaning that it can’t be the motor adjustments driving learning–it made no difference when they were allowed to make them. Instead, if our sensory system learns that no, our arm will go over there,  not over there, when we engage certain muscles, then the next time we have that goal we’ll be able to pull up the right motor trajectories for that goal. So learning to predict the future, the future within our arm’s reach anyway, is to learn to control it.

[Tseng, Diedrichsen, Krakauer, Shadmehr, & Bastian 2007]

3. On to some of Bastian’s split-belt treadmill stuff. She asked, why do we learn? Why don’t we just keep limping after an injury–what’s wrong with that? Well, limbs are expensive, metabolically speaking. If you walk symmetrically, you exert much less effort. Bastian’s team measured people’s carbon dioxide output as they walked on a treadmill that was split down the middle, causing their two legs to walk at different speeds. Remarkably, people can deal with this and even get so good at it that their walk goes from a limp to a swagger. You hardly notice their legs have different step sizes, the walk becomes so smooth. Crazily, people can also walk forward with one leg and backward with the other. They found that when you learn a new speed, it is learned in a leg-specific and a direction-specific way. What you learn walking forward, your motor system doesn’t automatically assume will apply to walking backward. Ditto for the right and left legs–they each seem to have independent systems for learning. With this specificity of learning, the brain does upkeep for its expensive locomotion habit by straightening things out whereever needed, should we become injured, wear a pair of high-heeled shoes, or gain or lose weight. This knowledge can be leveraged to help customize people’s rehabilitation regimens, targeting the limbs and movements that need it most.

[Choi & Bastian 2007]

4. Now, this last one is my favorite, so, congratulations to you for reading this far. Imagine your friend is injured. What do you do when you go see them in the hospital? Do you offer to help them out of bed, or do you poke at them as they try to get up and laugh? I hope you said you help them, you monster. Well you’re wrong! I mean, no, you’re right, but not as right as you’d think. To rehabilitate someone, you’d think it would be a big help to hold their hand and walk them through whatever it is they’re relearning. That’s how you learned to ride a bike, right? Someone running along behind you, holding the seat? While this is nice, unless you intend to follow your friend around forever, you better knock it off. Patients learn better if you exacerbate their errors. That’s right. If someone’s limping a bit one way, push them a bit farther that way (Clarification: don’t you push them, and don’t tell anyone I told you to–this is what their PT should be doing, you dingus). This will help them learn to push back. If they’re making do with a limp, push them off-kilter enough that they have to catch themselves. Importantly, though, be gentle–the error you cause has to be within a somewhat normal range for them. If you push someone so far they’ve never experienced pushing back that much, they won’t be able to do it. You’ve got to push them to adjust more frequently for errors that are above-average in size. Eventually, they’ll be able to correct for their limp.

[Torres-Oviedo & Bastian 2012]

And so, dear readers, this is of course the part in my rhapsodizing where I tell you What It All Means, because this pushing a limping person thing, it is a metaphor for life. When life knocks you down, all you want to do is hole up in your comfort zone with some Ben & Jerry’s and Toddlers & Tiaras National Geographic documentaries. But no, you need to get out there, slugger, and push yourself, but only within your limits. Try new and difficult things, but be realistic about what you can do. It is the only way you will heal.



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SfN Day 3 (?) Highlight: A BMI in V1

That I stopped blogging my SfN highlights the same day I took care of Ned the Neuron is no coincidence. That guy loves making new connections.

While plugging into an outlet to power up, Ned and I looked up to see our friend Ryan Neely at his poster! Hi, Ryan! And so, while keeping careful watch of our possessions, Ned and I learned about what Ryan is up to these days. Ryan works with Jose Carmena on brain-machine interfaces (BMIs). A BMI usually consists of a sensor implanted in the brain, some kind of actuator like a cursor or a robot arm, an encoding algorithm to act as a lookup table between brain activation patterns and body movements, and a decoding algorithm to translate brain activity into action. An early goal of BMI research was to help patients who had lost a limb or function of a limb by reinstating control over their environment.

Work by Aaron Koralek, a recent Carmena lab alum, showed that rodents could learn to control the auditory tone they heard, from high to low, by ramping the activity of one group of neurons up and ramping the activity of a different group of neurons down. If they hit just the right tone and sustained it, they got a reward. And to show that these animals had truly learned a new skill and not picked up a new habit, they showed that if they offered a reward that the animal was at the moment sick of, either sugar or chow, they stopped working for it. These new skills seemed to rely on the strengthening of the circuits between the primary motor cortex and the striatum, an area deep within the brain implicated in both learning and storing habits and skills.

These animals had sensors implanted in their motor cortex, and without moving, they were able to drive activity in targeted groups of neurons up or down. How these groups form their allegiances, we aren’t sure. We do know that BMIs work better when both the encoding algorithm and decoding algorithm are allowed to be flexible, learning each other as both the brain and the algorithms update.

But so far, having only decoded from motor cortex, we figure the brain activity that drives all our encoding model’s power comes from motor imagery. When we imagine a movement, the brain is activated in a strikingly similar way, compared to when we actually execute movements. Motor imagery is so reliable, in fact, that it was used to detect signatures of consciousness in people in vegetative states. Simply asking them to imagine playing tennis or walking around their home, and then analyzing the patterns of brain activation, yielded reliable “yes” and “no” answers. Crazy.

So, ok, now imagine you’re a BMI researcher and you want to know, does this work for motor imagery only? Are we limited to making BMIs that do what arms and legs do? Which is awesome, but we’re not even really sure why decoding motor imagery into motor behavior works. Those “two groups of neurons” that are ramped up or down to raise or lower the tone of a cursor? Dunno. Statistics and magic. We call each group an “ensemble,” because they act together, but it’s unclear what, subjectively, the animal (or human) would be doing to change these ensembles’ activity. For all we know, the animals could be envisioning playing tennis to make the tone go higher or walking around his home to make it go lower.

Enter Ryan. Ryan is doing something kind of crazy, which is measuring activity in V1, or the primary visual cortex. At first blush, this seems like it will never work. We can consciously control our motor cortex’s activity by using motor imagery, but the visual cortex is a sensory area. Sen-so-ry. Got that? It’s in the business of input, not output.

Wait, what’s that you say? It worked. Hell yeah it worked. You see, the visual cortex is not as passive as its moniker would have you believe. It receives inputs from areas sandwiched between motor and visual cortex, and these areas are involved in attention. Injury to these regions in one side of the brain results in an inability to pay attention to things on the opposite side of space (visual input switches sides, left-to-right, on its way from the eye to the brain). Attention is thought to rain down on primary visual cortex to sharpen, enhance, and otherwise hasten your response to, whatever it is that you’re paying attention to.

So were the animals just changing how much they paid attention to things? Maybe. Don’t care. Turns out you can use a sensory cortex to drive a brain-machine interface. That is nuts. Does this mean you could someday use visual imagery to control robots? Does it mean robots could control you by showing you pictures? Does it mean having a “vision” for something really does, in a weird scientific/metaphorical fusion, sell us on the “If you can dream it you can do it” thing? Who knows! Science is fun and weird.

That was all of the science Ned and I took in that day, but we did have an awesome time at #sfnbanter, meeting Twitter folks. Whether we were up the next day for our 8:30 am talk, well, we’ll find that out in the next installment. Ciao for now, you beautiful, powerful mental imagery machines. Ciao.

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The Fall 2014 issue of the Berkeley Science Review is out!

Photo courtesy of the Berkeley Science Review. Original by me, image processing magic by Natalia Bilenko.

Photo courtesy of the Berkeley Science Review. Original by me, image processing magic by Natalia Bilenko.

You can peruse the issue online here. Or I can save you a click and you can skip right to MY piece here. I had a lot of help from my muses, the people I was writing about, in helping this feature get done on time, because as it turns out, features are hard! I thought it would be like that Mark Twain line, “I would have written a shorter letter, but I didn’t have time.” I thought longer would somehow be easier. Well, not if you want it to be good. So, thanks to them for keeping me close to the truth when time pressures almost ruined everything, round after round of edits. They are amazing people and friends and I’m proud to have publicized their admirable hustle.

Ned gets distracted from the poster sessions at SfN 2014.

Ned gets distracted from the poster sessions at SfN 2014.

In other news, obviously my post-a-day habit for SfN petered out after only a few days. To be fair, what really killed it was taking Ned the Neuron around to make new “connections” all day, including at the delightful Twitter party #sfnbanter. I’ll tell you, if you want a date to a Twitter party, you can’t beat Ned. He is so universally beloved, I actually lost track of him at the bar once or twice (don’t tell his mom!). But, we managed to leave together, both of us in one piece, AND still make it to an 8:30 am talk as well as my afternoon poster the next day. Which, by the way, thanks to everyone who stopped by!

Done with my poster! Woo hoo!

Done with my poster! Woo hoo!

I will post on the remainder of the amazing things from SfN soon. But as long as I’m yammering about SfN-related things that aren’t actual scientific content, I will close with three pieces of advice I received while at SfN, in descending order of utility:

1. “If you’re leaving academia to be a science writer, your dissertation is the least important thing you will write for the rest of your career, because only a few people will read it.” — A future science writing role model I was lucky to chat with

2. “I think I finally figured out why we have death. We need turnover of ideas. Can you imagine if all these old people never died and we were stuck with their shitty ideas forever?” — Not so much advice as perspective from a past advisor/role model

3. “Just keep saying to yourself, ‘It’s only a movie. It’s only a movie.'” — My present advisor, upon hearing that Berkeley’s fMRI scanner will be down for the month in which I’d scheduled 18 fMRI subjects, my dissertation’s Chapter 3. Sometimes there just isn’t any good advice, I guess.

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SfN Day 2 highlights

Day 2: Big day. Tweets will have covered most of this. While “SfN” has been “cracking down” on the livetweeting, apparently the big talks are ok. All the other talks, you have to wait a whole fifteen minutes til it ends. We’ll live. On with the show:

Never trifle with a multisensory perceptron when experience-dependent plasticity is on the line

Thanks to the booze rooster, I was up and at ’em at 8 am checking out a session on the cerebellar theory of autism. Sam Wang from Princeton ran the session and gave a standout talk. I should mention before diving in that this is the same Sam Wang whose election forecast models beat Nate Silver’s in the 2012 presidential election.

But that’s neither here nor there. Wang is also a neuroscientist, and a big proponent of the idea that autism is the result of dysfunction in the cerebellum. People with autism spectrum disorder consistently have abnormalities here, but there’s a paradox: If adults get an injury here they end up with an impaired ability to move, not autism. So Wang proposed that the damage must occur during what is known as a sensitive period to result in autism. This process he likened to the superfamous sensory deprivation experiments by Hubel & Wiesel, in which they sutured the eye of a young cat shut and saw that the deprived visual cortex failed to wire up properly. This only happened during a certain window of the cat’s early life, which told them that for normal function, the visual system requires stimulation in that window and once it’s passed, it’s too late.

Wang argued that, because the cerebellum acts as a neuronal machine for multisensory learning, if it sustains an injury early in life then all of the areas it connects to will fail to wire up properly. Because this doesn’t happen for adults with cerebellar injury, this means the cerebellum plays a special role in wiring up the brain during development. The association cortex, where sensory information is built up into more high-concept information, is deprived of the cerebellar guidance it needs. This lack of sensory convergence in the brain could explain some characteristics of autism spectrum disorders.

I’m “on” so many posters this year! Recognize my signature orange corduroy jacket?

Poster: Choking under pressure

I visited Taraz Lee and Scott Grafton’s poster on choking under pressure. Taraz carefully designed a study where people could receive 5, 10, or 40 dollars for completing a difficult motor task correctly. At the end of the experiment, he chose one trial at random for their payout, meaning it behooved them to bank a bunch of $40 trials. The $40 trials were kept rare to drive up the pressure, and people choked more often on them than on the $5 or $10 trials.

They used functional magnetic resonance imaging (fMRI) to scan their brains as they completed the task. In their recent paper, they found that the people who ended up choking less on these trials also had greater connectivity between their thinky, task-oriented, rule-loving dorsolateral prefrontal cortex (dlPFC) and their action-generating primary motor cortex (M1). “Connectivity,” of course, meaning their slow changes in blood flow tended to change in tandem.

In their current study, they used transcranial magnetic stimulation (TMS) to disrupt activity in the dlPFC. This increased the sensitivity to monetary pressure in a bunch of brain regions, causing others to compensate. TMS also turned “champions” (people who did better under monetary pressure) into “chokers.” Currently, Taraz & Scott need more data to see if this emerging pattern holds, but I like to think of the dlPFC as bracing and tightening and focusing as hard as it can on M1 the way a gymnast tries to summon laserlike focus on a balance beam. I sometimes anthropomorphize brain regions.

Ned stickers!

New Hero: Mahzarin Banaji

Banaji’s talk explored how we form in-group biases. Newborn babies will mimic facial expressions–we’re like Krazy Glue when it comes to picking up the expressions and habits of those around us. That’s how we charm our caregivers as babies, and we keep on doing it because someday this is how they will know to take care of us. We’re like them.

Discrimination, she said, isn’t as much about excluding people not like you as it is about giving preference to people like you. Really what we need is a diversity of perspectives. Next time you interview assistants, grad students, whoever–try to be just a little bit open-minded, and you’ll end up rich in the perspective that uptalking weirdo you hired brings. Geniuses aren’t always easy to spot in a crowd.

This applies to all kinds of intergroup behavior, and as it turns out, we are total idiots when it comes to deciding who’s good, who’s competent, who to trust. Simply decreasing the distance between a person’s eyes, studies have shown, will make complete strangers judge a face as dumber. These judgments come out of nowhere–what does it even MEAN, she asked, to say someone has an “honest smile”? And yet, the facial features that cause people to be viewed as “more competent” have predicted the margin of victory in every presidential election. There is no reason to think these heuristics are real or useful, and yet there they are, their fingerprints all over our minds whether we like it or not.

Look at these insatiable nerds.

Look at these insatiable nerds. Still arguing as the poster is being rolled up. They’re the most dedicated people I know, probably.

Tom Jessell: You are nothing without your vestibular system

Motor learning people like to start off their talks by saying something like “The human brain is for producing movement.” We say this because people studying all the fancy stuff like thoughts and feelings and the fun tricks that differentiate us from the animals, well, they tend to get most of the attention, and we have a bit of a chip on our shoulder about it. Movement is freaking amazing, ok? Just because your dog can do it doesn’t make it a dumb trick.

So anyway I don’t know if he meant to bait and switch, but it was pretty great. Try all you want to produce movement without a good solid vestibular system, but you won’t get very far. This system is a set of fluid-filled canals just beyond the eardrum that helps us balance and generally keep track of our body position in space. This information gets sent to neurons in the spinal cord responsible for twitching the muscle fibers to make us move. Jessell first pointed out that without inhibition from interneurons using the neurotransmitter GABA, wildly oscillating movements result. That is because this inhibition tells the motor neurons when to listen to the feedback and adjust for it and when to just keep on going with the smooth movement. When they administered diptheria toxin to mice to selectively destroy this inhibition, their movements became corkscrewy and hopelessly off-course.

He then talked about how normally, our extensor and flexor muscles work in alternation. Whether bending your knee to walk or flexing a bicep for an admirer, the muscle on one side of the limb is stretched while the other one can go more slack. However, when you, say, fall or lose your balance, they contract at the same time. By playing around with the inhibitory interneurons, altering the function of the pumps that maintain disequilibrium of chloride ions inside and outside the cell, they can switch the inhibition to excitation. They could manipulate the switch from alternation to co-contraction of muscles, and the result was…ok. Imagine if your fingers were so tightly outstretched, your toes too, that if you crawled around you were teetering atop your flexing, rigid fingers. Ballet-style en pointe, on your fingers. Watching a rodent do this was unsettling and weird and it made me deeply appreciate my vestibular sense and its amazing inhibitory interneurons.


That’s all for today, nerds. I don’t know why I’m still up, except for oh wait, it’s DC, so of course there is a pack of feral 22-year-olds above us doing superloud youthful things. Ugh. I hope they lose their vestibular senses so they collapse in a heap and this infernal pounding stops.


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