Gaëlle Desbordes, PhD
Research Interests
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Quick links: Home Publications Curriculum Vitae (also in PDF) |
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Current work: Meditation neuroscience |
I am currently working on two studies to investigate
meditation from a neuroscientific perspective, using
functional magnetic resonance imaging (fMRI) and
simultaneous recordings of autonomic markers (cardiac,
respiratory, and electrodermal).
The first study is part of a multisite investigation of
meditation and mind-body health
(the Compassion
and Attention Longitudinal Meditation (CALM) study, in
collaboration with
Chuck
Raison at University of
Arizona, Tad
Pace at Emory University, Eric
Schwartz at Boston University, and other collaborators at
the Massachusetts General Hospital (MGH)-Harvard-MIT
Martinos
Center for Biomedical Imaging in Boston.
The first results from this study are now published in the journal Frontiers in Human Neuroscience (Full article available here). I recently presented these and other new results at several conferences, including the The second study is an exploration of the neural and physiological correlates of more advanced forms of meditation practice which may enable top-down regulation of homeostasis mechanisms classically considered to be beyond voluntary control. These two projects are funded by the NIH (NCCAM) with grants R01AT004698, R01AT004698-01A1S1 (P.I. Raison), and ARRA RC1AT005728 (P.I. Schwartz), and by a Varela Award from the Mind and Life Institute.
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Other projects |
| I also recently started collaborating with
Vitaly Napadow
on the neural (fMRI) correlates of itch
and its treatment with acupuncture.
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Previous postdoctoral work: Population coding in the early visual system |
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I was previously a postdoctoral fellow
in Garrett
Stanley's group, at Harvard University and then at
Georgia Tech (in Atlanta). My work was on neuronal
population coding in the early visual pathway. I was
investigating the neural code in the Lateral Geniculate
Nucleus (LGN) at the scale of small populations of
neurons (n = 10-12 neurons).
Neurons convey information about the world in the form of trains of action potentials (spikes). These trains are highly repeatable when the same stimulus is presented multiple times, and this temporal precision across repetitions can be as fine as a few milliseconds. It is usually assumed that this time scale also corresponds to the timing precision of several neighboring neurons firing in concert. However, the relative timing of spikes emitted by different neurons in a local population is not necessarily as fine as the temporal precision across repetitions within a single neuron. I showed that the temporal scale of the population code entering visual cortex is on the order of 10 ms and is largely insensitive to changes in visual contrast. Since closely timed spikes are more efficient in inducing a spike in downstream cortical neurons, and since fine temporal precision is necessary in representing the more slowly varying natural environment, preserving relative spike timing at a ~10-ms resolution may be a crucial property of the neural code entering cortex (Desbordes et al., 2008). I then found that fine spike timing precision—within single cells as well as across nearby neurons in the local LGN population—was continually modulated as the visual stimulus unfolds, and that this modulation could be captured by a generalized linear model (GLM) that combines stimulus-driven elements with spike-history dependence associated with intrinsic cellular dynamics (Desbordes et al., 2010). |
Last update: Feb 8, 2013