Boas Blog: Brain Mapping
Gary at Large
San Francisco, June 23, 2009
The concierge didn't think I could do it. Or would do it, anyway. "Walk from Union Square to the Presidio?" he asked. (Did he just suppress a chortle?) "There are a lot of hills here, you know."
"Why not?" I replied. "I'm relatively young. Somewhat sturdy. I can do it." I fixed him with an icy stare, which I'm sure came across as anything but intimidating. And with that I gathered my belongings, stepped out into the San Francisco morning and began my long trek.
I had a destination in mind. While I'd mapped out a route that would take me to the "Crookedest Street" and San Francisco Maritime National Historical Park, and eventually to the northern tip of the Presidio, with its hazy, impressionistic views of the Golden Gate Bridge, I mostly wanted to visit the Exploratorium - the museum of science, art and human perception housed in the Palace of Fine Arts on the eastern edge of the Presidio.
Lombard Street, the "crookedest" in San Francisco. (Photonics Media photos by Gary Boas)
The museum offers a state-of-the-art microscope imaging station, where visitors can look at fruit flies and zebrafish, for example, using research-grade microscopes. I played at the station for a while, exploring stem cells and reading about the potential benefits of stem cell research, and then went downstairs to see if I could find further information about it.
The woman in the Resource Center could not have been more accommodating. Though I'd totally walked in off the street and, I'm sure, looked more than a little bedraggled (it was rather warm outside, and there are indeed a lot of hills in San Francisco), she asked if I would like to talk to one of the scientists and immediately picked up the phone to arrange something.
Kristina Yu, on the other end of the line, was equally accommodating. She was about to step into a meeting, she said, "but are you at large in the museum? Can you meet me in 45 minutes?"
The microscope imaging station at the Exploratorium.
"I am indeed at large," I responded. "I'll see you then."
Later, Kristina gave me a tour of the Life Sciences section of the Exploratorium and then showed me the labs, where she and the other biologists and microscopists work to support the current exhibits and develop new ones. I have to say, it was an impressive setup.
We also talked about education, which is central to all of the museum's activities. In addition to maintaining the museum itself and extensive online exhibits, the Exploratorium offers teacher training, outreach to underserved communities and "Science Snacks" (miniature versions of some of the museum's exhibits) for use in the classroom. Education is of course a pressing concern in the sciences, one that we at Photonics Media plan to cover regularly and in-depth.
I thanked Kristina, took my leave of the Exploratorium and began the long walk back to the hotel, where I will catch a shuttle to the airport. As I write this, I'm sitting in a coffee shop on Union Street - on a stretch called "Cow Hollow," apparently. I've had a great time here in San Francisco, exploring the city and catching up with old friends, but more importantly I've learned all kinds of exciting things about the brain and about science in general. It's time to go home, though. I'll see you next time.
Making the Inscrutable Scrutable
San Francisco, June 22, 2009
In flipping through my notes looking for a topic for today's blog, I kept coming back to the following, scribbled hastily in nearly indecipherable handwriting: "Memories consist of widely distributed networks made of neurons synaptically modulated by experience." There's nothing remarkable here - at least, not in the context of a meeting given over entirely to such statements. Yet I kept returning to this page. Something about it took hold of my imagination and wouldn't let go.
What was it, though? I chewed on this question for some time, and finally it dawned on me: I was intrigued by the attempt to break down into component parts - to explain using scientific means - what has always been an essentially romantic concept. Memory is associated with longing and desire, loss and regret. It is source material for "Cats," and the root of nostalgia for a simpler, better time.
Memory has also always been more or less inscrutable. You know what it is, of course, but you can't hold it in your hand, poke and prod it, try to figure out how it works. Yet here was a researcher doing just that. Listening to him rock back and forth between the deeply mysterious and the thoroughly explicated was actually kind of a thrill.
Much of the meeting has been like that, though. Listening to talks about memory, learning and decision-making, I have been struck by the difficulty of the task at hand: working out how we know what we know, for example, or what precisely enables us to exercise our free will. By imaging otherwise imperceptible changes in blood flow in hidden folds of the brain, the investigators have somehow achieved a better understanding of, well, the human experience.
But not through imaging alone. Brain mapping is almost by definition a multidisciplinary endeavor and the meeting has benefited from the perspectives of researchers whose primary gig is elsewhere. A philosopher discussed morality. A psychologist talked about musical intelligence. Alan Baddeley, who delivered a keynote lecture on working memory, admitted up front that he was "not exactly an expert" in neuroimaging. "I assume the organizers knew that when they invited me," he said. At least that's what I think he said. I really can't make out what I scrawled in my notes.
Deconstructing Morality, Voxel by VoxelSan Francisco, June 21, 2009
Here's a little tidbit I don't often mention, at least not in the company of scientists: I studied anthropology back in the day (music and anthropology, actually, but that's another story). I'm still intrigued by the social and cultural underpinnings of this and that, so I'm pleased that such questions have figured in many of the sessions I've attended here at the Human Brain Mapping meeting.(Incidentally, I'm fascinated by the social and political economies of the research community in general, and have been studying them - quietly, methodically - for nearly 10 years. Someday I'll write that book.)
The meeting kicked off on Thursday with the Talairach Lecture, presented by Patricia Churchland of the University of California, San Diego. Churchland studies and writes about the interface between neuroscience and philosophy - including such weighty topics as free will and the self - and in this talk discussed "Morality and the Social Brain."
She began by positing that moral values are built upon a platform of attachment and trust. Animals are programmed for self-preservation, she explained. This instinct applies also to their offspring, and in highly social animals to others in their immediate group. Thus attachment and, ideally, trust.
This was relatively familiar ground. Churchland went on, though, to relate this instinct for social preservation to findings from brain imaging studies, specifically to oxytocin receptor levels (oxytocin is a hormone found in mammals that also acts as a neurotransmitter). For example, prairie voles and montane voles - cute little guys, all of them - exhibit very different behaviors with respect to mate attachment. As it turns out, they also exhibit very different oxytocin receptor levels. Similarly, in other mammals, these levels have been shown to increase in a mother just before she gives birth - thus ensuring her attachment to the pup, it seems.
Now, this is all well and good in terms of explaining particular behaviors, but how do we get from here to the decidedly more esoteric realm of morality? Churchland views morality not as a well-circumscribed set of rules - as many others do, of course - but essentially as a series of decisions based on attachments: In a given situation, how does one ensure the well-being of the group? We humans, in particular, have enlisted our enlarged prefrontal cortex to develop assorted social practices and problem-solving skills to facilitate this. And from these the concept of "morality" emerged.
Life, the Universe and Human Brain Mapping
San Francisco, June 19
Four hundred years ago, in June of 1609, many astronomers still believed that the heavens rotated around the Earth. And not just astronomers: Pretty much anyone who contemplated such things subscribed to the notion of a geocentric universe. Why wouldn't they? Centuries of observations by the naked eye suggested a cosmology in which planets and stars circled the Earth in an eternal celestial dance.
That very summer, though, the eldest son of an Italian lute player built his first 3X telescope and launched a study that would set all of this on its head. In January 1610, after tracking Jupiter and "three fixed stars, totally invisible by their smallness," Galileo Galilei determined that the "stars" (moons, it turned out) were orbiting the planet. This conclusion did not square with Aristotle's widely accepted conceptualization of the cosmos, and incidentally landed Galileo in hot water with the Catholic Church. Still, his continuing observations shaped and confirmed an alternative, heliocentric understanding of the Earth and its neighbors – one that most people now regard simply as fact.
What can we take away from the tale of Galileo? Among other things, this: Our universe is defined by the tools at our disposal.
The final great frontier, perhaps, is the human mind: the stomping ground of consciousness, the fountainhead of thought. The ancients - a cavalcade of Greek, Indian and Islamic thinkers - puzzled over the nature of consciousness, contemplating the relationship between the mind and the soul and debating where exactly each resides. Physicians and philosophers eventually worked out that the mind, at least, makes its home in the head. Still, questions remained: Where precisely might one find the "higher" intellectual functions, including reason and memory? And what about the passions? From where do love and joy; fear, lust, greed and envy arise?
Recent decades have given us tools with which to probe these questions, to identify regions of the brain associated with particular cognitive functions and emotional responses. This area of study, which has come to be known as "brain mapping," has largely been the purview of functional magnetic resonance imaging - with high-resolution scans revealing changes in blood flow coupled with neural activity, itself associated with cognitive tasks or emotional stimuli, for example. Optical imaging has also yielded important findings, though, often by measuring the same hemodynamic responses.
Together, these tools have helped us paint a detailed picture of what goes on in the brain and how it relates to a universe of behaviors and conditions - and thus understand, at least a little better, who we are, what makes us human.
The 15th annual meeting of the Organization for Human Brain Mapping kicked off on Thursday, here in San Francisco. I arrived on Thursday afternoon and will be here for the duration of the conference. I'll post updates when I can. Check back to see what I've learned. In the meantime, here's a couple familiar views of San Francisco:
After working in the research community as a writer and editor, Gary Boas joined Laurin Publishing in 2001. Today, he is a news editor for BioPhotonics magazine and a contributing editor to Photonics Spectra. In addition, he continues to crash as many academic cocktail parties as he can.
- An instrument consisting essentially of a tube 160 mm long, with an objective lens at the distant end and an eyepiece at the near end. The objective forms a real aerial image of the object in the focal plane of the eyepiece where it is observed by the eye. The overall magnifying power is equal to the linear magnification of the objective multiplied by the magnifying power of the eyepiece. The eyepiece can be replaced by a film to photograph the primary image, or a positive or negative relay...
- The technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. The science includes light emission, transmission, deflection, amplification and detection by optical components and instruments, lasers and other light sources, fiber optics, electro-optical instrumentation, related hardware and electronics, and sophisticated systems. The range of applications of photonics extends from energy generation to detection to communications and...
- An afocal optical device made up of lenses or mirrors, usually with a magnification greater than unity, that renders distant objects more distinct, by enlarging their images on the retina.
MORE FROM PHOTONICS MEDIA