Above: Martha Farah, Ph.D. and Geoff Aguirre, M.D., Ph.D.
introduced us to imaging today through a series of great lectures.
And we’re off! Boot Camp has officially started, and I am
already officially overloaded with things to say about the experience. But
don’t worry. I’m not going to paste in my lecture notes. Instead, I’ve come up
with a three-pronged strategy to deliver the goods: (1) a short play-by-play of the day; (2) things
that we learned today that seem really really really really really really
ridiculously good looking important (if you don’t get the joke, google
“Zoolander really”); and (3) more on the interesting people I’ve met. Also, for
those who can’t attend, you may have a chance sometime in the future to attend
via video (if plans work out to construct a video lecture series in the Fall).
(Click below for more).
After a free breakfast (bonus points
given for having a lot of fruit salad), Martha introduced the program and had
us each introduce ourselves. She emphasized, as I mentioned yesterday, that
this is a program for non-neuroscientists. The goal of boot camp is to
improve the speed of take-up and quality of research in the many different
disciplines neuroscience may intersect. To do this, we’ll have a combination of
lectures, break out sessions, and labs. This will sum up to a program that
Martha describes as a “highly abridged undergrad course,” with the material
focused primarily on higher level processes in the brain since higher level
cognition is most relevant to the disciplines represented.
Going around the room for introductions by participants, it was amazing to hear the diversity of the group. We have novelists, science writers, lawyers, philosophers, economists, psychologists, business school professors, political scientists, private sector representatives, and even a Tsunami survivor (more on him another day – but he climbed a tree, survived, and is now doing research motivated by the experience). For those thinking about boot camp in the future, you should know that a majority of us announced that we have little to no formal training in neuroscience. If you consider yourself a neuroscience newbie, this is the place for you to be
Martha’s first lecture gave us some important historical
perspective on neuroscience generally, and imaging in particular. At lunch, a
group of us went en masse to the beautiful Pottruck Health
and Fitness Center to sign up for our 2-week memberships. Lunch credit is
provided for on-campus dining at the Houston
Market. This is a nice approach, as it allows you a great amount of choice
in filling your belly. Full and ready to really get into the nitty-gritty of
imaging, we were treated to energetic afternoon sessions led by Geoff Aguirre. Geoff is a dynamite
teacher, and made some complicated processes seem understandable. We finished
the day with a tour of the fMRI facilities here at Penn, and participants had
an opportunity to slide into a mock fMRI scanner to see what it feels like to
be inside. We finished a little after
Today’s big lessons were:
- understanding the brain’s architecture as a parallel distributed processing (PDP) network;
- placing neuroscience and fMRI in historical context;
- the physics underlying Magnetic Resonance methods;
- the importance of distinguishing between the system of cognition (how external stimuli lead to neuron firing), and the system of neuro-vascular coupling (how neuron firing leads to fMRI images), ... explained through a very detailed step-by-step discussion of how fMRI images are generated.
I can’t cover each of these important topics in the space of
a blog post, but if you’re interested in a more complete version of the notes
once boot camp is finished please email me in a few weeks when I have them
ready. In the meantime, I want to focus on the last thing I mentioned: the
distinction between these two systems that take us from experimental conditions
to pretty brain image. Geoff suggested that if you can understand linearity and
the distinctions between these two systems, “you will be ahead of 55% of folks
who do work in this field, and haven’t captured this idea”. Now, Geoff may just
be trying to make us feel better (and if so, it worked!), but his main point
was an incredibly important one: the [ External stimuli à Neurons firing ]
system (call this “system 1”) is distinct from system #2: [ Neurons firing à
Nerve cells à
alter local blood flow à alter concentration of deoxy hemoglobin à
changes the rephasing à changes the T2* signal à gives us an image of
the brain with the amount of Deoxyhemoglobin at any particular point ]. If
system #2 seems complicated, that’s because it is. Really complicated.
So complicated, in fact, that neuroscientists are still working to understand
the precise pathways. And so complicated that many researchers who use fMRI
don’t understand the underlying chemistry and physics either.
But what Geoff emphasized is that system #2 is linear, meaning roughly that if you double the input (e.g. the number of neurons firing) you’ll double the output (e.g. you’ll see more activation). BUT, and this is a big but so that’s why it gets all caps, the linearity of system #2 does not mean that system #1 is linear. Just because I show you brighter lights or play louder music does not necessarily mean that more neurons will fire. Indeed, trying to define the relationship between external stimuli, such as an experimental condition, and neuron activity is what the research and hypothesis testing is all about.
It’s tough to stop here, since so much of Geoff’s presentation is also really important, but in the interest of time and space, let me transition.
III. Who's at boot camp with me?
Two business school professors, Gal Zauberman of Wharton and Jeff Galak of Carnegie Mellon, are both doing really neat consumer research on decision-making, marketing, and a host of other cool topics.
Gal will have an fMRI study up and running soon, and Jeff is an emerging superstar, having his recent research on commercials and consumer happiness featured in all the big media outlets. He’s created the Consumer Behavior Lab, and I can report that he’s also an excellent roommate!
I had other great conversations today with lawyers, professional writers, an anthropologist, a political scientist, and philosophers. I’m hoping I can profile a few of them as the camp continues.
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