Events

Oct 04, 2016
12:00 PM

 

Abstract

Deep brain stimulation (DBS) has been highly effective in the treatment of movement disorders, and has undergone multiple clinical trials in psychiatric disorders. There have been promising early results in major depression (MDD) and obsessive-compulsive disorder (OCD), but blinded and randomized trials have not reliably shown a signal. Even in successful trials, a third or more of patients do not respond at all. Part of the problem is that we apply DBS at anatomically defined targets, without a clear understanding of how it affects brain function or how that might map to response or adverse effects. I will overview the state of our knowledge, then present early results from electroencephalography (EEG) studies seeking to map those mechanisms at the level of cortical oscillations. We have identified a possible mechanism of action that modulates a fronto-cingulate network involved in top-down control. The other major question is whether traditional psychiatric diagnoses (based on symptom checklists) are the right way to define a DBS-eligible population. I will present early results from TRANSFORM DBS, an MGH-led effort to deliver DBS targeting functional domains and their underlying neural circuits.

 

About the Speaker

Read more about Dr. Widge's research and interests here http://scholar.harvard.edu/awidge/biocv

Oct 12, 2016
12:00 PM
Oct 19, 2016
12:00 PM

 

Abstract

Magnetic resonance imaging of the human brain and spinal cord at an ultra-high magnetic field of 7 Tesla offers new opportunities to visualize structures with high spatial resolution and enhanced conspicuity, and to detect functional networks with greater sensitivity. This talk will highlight some of the technical challenges and recent advancements in functional imaging of the human brain and spinal cord at 7 Tesla, and discuss how this research may translate to the clinic to facilitate a more complete understanding of biological processes and etiologies of central nervous system diseases such as multiple sclerosis and spinal cord injury.

About the Speaker

Robert Barry completed his Ph.D. in Biomedical Engineering at the Centre for Functional and Metabolic Mapping at Western University in London, Ontario, Canada, and then pursued postdoctoral studies at the Vanderbilt University Institute of Imaging Science in Nashville, Tennessee. In 2014, he was the lead author on a publication demonstrating the first conclusive evidence of resting state correlations in the human spinal cord using functional MRI. Robert is the recipient of a K99/R00 award, and joined the Martinos faculty in June 2016 to pursue neuroimaging of the brain and spinal cord at ultra-high magnetic fields.

Oct 21, 2016
12:00 PM

 

Abstract 

Magnetic resonance (MR) imaging technologies provide unique capabilities to probe the mysteries of biological systems, and have enabled novel insights into anatomy, metabolism, and physiology in both health and disease. However, while MR imaging is decades old and has already revolutionized fields like medicine and neuroscience, current methods are still far from fully realizing the potential of the MR signal. In particular, traditional methods are based on the Fourier transform, and suffer from fundamental trade-offs between signal-to-noise ratio (SNR), spatial resolution, and data acquisition speed. These issues are exacerbated in high-dimensional applications, due to the curse of dimensionality. Our work addresses the limitations of traditional MR imaging using signal processing approaches that have recently become practical because of improvements in modern computational capabilities. These approaches are possible because of the "blessings of dimensionality," i.e., the observation that high-dimensional data often possesses unexpectedly simple structure, which can be exploited to alleviate the classical barriers to fast high-resolution imaging. This seminar will describe approaches we have developed that use novel constrained imaging models (based on sparsity, partial separability, linear predictability, etc.) to guide the design of new MR data acquisition and image reconstruction methods, and enable substantial acceleration of both low-dimensional and high-dimensional MR imaging experiments. These methods will be illustrated in the context of applications such as fast high-resolution T1-weighted anatomical imaging, fast sub-millimeter diffusion imaging, ungated free-breathing cardiac imaging, and a novel high-dimensional diffusion-relaxation hybrid experiment that provides unique insights into tissue microstructure.

About the Speaker

Justin Haldar received the B.S. and M.S. degrees in Electrical Engineering in 2004 and 2005, respectively, and the Ph.D. in Electrical and Computer Engineering in 2011, all from the University of Illinois at Urbana-Champaign. He is currently an Assistant Professor of Electrical Engineering and Biomedical Engineering at the University of Southern California, where he co-directs the Biomedical Imaging Group and is affiliated with the Signal and Image Processing Institute, the Dana & David Dornsife Cognitive Neuroscience Imaging Center, and the Brain and Creativity Institute. His research interests include image reconstruction, signal modeling, parameter estimation, computational methods, and experiment design for imaging problems, with a particular focus on biomedical magnetic resonance imaging applications. His research has been recognized with a 2014 CAREER award from the National Science Foundation, a best student paper award at the 2010 IEEE International Symposium on Biomedical Imaging, and the first-place award in the student paper competition at the 2010 international conference of the IEEE Engineering in Medicine and Biology Society. He is a member of the IEEE Signal Processing Society's Bio Imaging and Signal Processing (BISP) Technical Committee, a member of the IEEE Signal Processing Society's Computational Imaging (CI) Special Interest Group, and an Associate Editor for IEEE Transactions on Medical Imaging.

Oct 26, 2016
12:00 PM

 

Abstract

It is widely known that almost all cortical areas consist of heterogeneous fine-scale neural clusters that show different selectivity and response profile and play different functional roles.  However, due to the low spatial resolution of neuroimaging techniques, especially in human studies, this heterogeneity is usually ignored, and cortical areas are treated as one single homogenous unit.  Unfortunately, this may lead to wrong and misleading interpretations of neuroimaging results about the functional role of cortical areas. Secondary visual area (V2) is a good example of this heterogeneity.  More than 30 years ago, histological studies in non-human primates showed that V2 consists of three different stripe-shape structures.  These fine-scale structures were categorized into thin, thick and pale stripes according to their size and their level of myelination.  Subsequent single cell and optical imaging studies showed that these stripes serve different functional purposes, and are part of segregated processing streams. In humans, until recently, evidence for such fine-scale cortical structures was limited to a handful of postmortem histological studies. Due to the low spatial resolution of the conventional neuroimaging techniques, no previous study had shown any functional evidence for these stripes, and V2 was treated as one homogenous cortex. 

Recently, by taking advantage of high-resolution fMRI based on using ultra-high field (7T) scanner, we demonstrated the first functional evidence for these stripes in humans (Nasr, Polimeni and Tootell, 2016).  We have also shown evidence for similar fine-scale cortical structures in the subsequent visual area V3. In this talk, I will start with a brief presentation of our recently published results.  Then, I will demonstrate our new findings about the functional properties of these fine-scale cortical structures (e.g. selectivity for color, disparity, shape and spatial frequency) in V2, V3, V3A and V4 and explain how ignoring this heterogeneity can lead to misinterpretation of the findings.      

Suggested  Readings:

-       Nasr, S., Polimeni, J. R., & Tootell, R. B. (2016). Interdigitated color-and disparity-selective columns within human visual cortical areas V2 and V3.The Journal of Neuroscience36(6), 1841-1857.

-       Nasr, S., & Tootell, R. B. (in press). Visual Field Biases for Near and Far Stimuli in Disparity Selective Columns in Human Visual Cortex. NeuroImage.

About the Speaker

I was born and raised in Tehran, Iran.  I received my B. S. (1999) and M. S. (2002) in Biomedical engineering from Shahid Beheshti Medical University (SBMU) and Iran University of Science and Technology (IUST) respectively.  I received my Ph. D. in cognitive neuroscience from the Institute for Research in Fundamental Sciences in 2009 under the supervision of Dr. Hossein Esteky. Then I moved to the U.S. to join Dr. Roger Tootell’s lab as a post-doc.  Since 2014, I have been an instructor in radiology at Harvard Medical School and assistant in neuroscience at Massachusetts General Hospital.  

Nov 02, 2016
12:00 PM
Nov 09, 2016
12:00 PM

 

Abstract

The Primordial Enigma is a smaller-formatted replica of the monumental Polyptych (4.4m x 4m x 0.50m) of the same name commissioned by the Director of the Veneranda Fabbrica del Duomo di Milano for the forthcoming EXPO 2015 at the Duomo of Milan. At the initiative of Professor Bruce Rosen this replica came into existence and is displayed at the Athinoula A. Martinos Center for Biomedical Imaging.  

The work is the culmination of an extraordinary adventure marked by Le Hasard et La Nécessité (Chance and Necessity), to quote the title of Jacques Monod’s famous essay: Chance -in my fortuitous milanese encounter with the Director of the VFDM that brought it to life, and Necessity -in its convergence with so many dreams and past compositions shaped by my profound interest in scientific discoveries in Astrophysics (quasars, exoplanets, dark energy, black holes…), Molecular Biology, Paleontology, and Philosophy (Teilhard de Chardin ), Psychoanalysis (Jungian Archetypes), Spirituality (the remarkable Rhenish abbess HIldegard of Bingen), as well as an abiding passion for masterpieces of the art world (Grünewald’s Issenheim Altarpiece). At the heart of this fascination lies the essential role of human intuition that led to this particular venue. Indeed, in initial sketches of the emerging Primordial Enigma in April 2013, inspired by The Legend of the True Cross based on Jacques de Voragine’s The Golden Legend, the thematic Tree of Knowledge immediately and strangely took the form of a gigantic brain. How moving to surprisingly discover a posteriori the existence of magnificent images of neuronal brain connections obtained by Human Connectome Project teams that scientifically validated my intuition: one of these images -in its original state- inevitably had to be integrated into my painting, because somehow it was expressing my concept: it was “my” Tree of Knowledge, the brain of the universe, the gigantic “Wak-Wak that converses with the comets!

Examples of Myth that anticipate science through intuition as in The (Premonitory) Portrait of Apollinaire by Giorgio de Chirico (1914), The Self-Portrait by Victor Brauner (1931), Afasia Rossa by E. M. Paraito, and The Primordial Enigma, demand our utmost consideration. Perhaps scientists experimenting on the brain have already found tentative explanations to this mystery. The fact remains that an artwork continues to be an enigma, not lending itself to simple responses despite the artist’s attempts to shed light on concepts that brought it to life and processes used in its completion; herein lies the pertinence of Duchamp’s teaching that it is the spectator’s role to recreate it. 

About the Speaker

Kathy Toma lives and works in Paris. Since her childhood she has dedicated herself to painting while completing university degrees (MA) in French Literature and Art History at the University of Strasbourg and PhD at the Sorbonne University, Paris, and theater and music studies at the Conservatory of Strasbourg.

Her pictorial works, shown in many exhibitions mostly in Italy and in France are using the synthesis of a semi-figurative language and Body Art: rooted in myth and memory, it brings into play different media that incorporate into classical painting Super 8 film, photography, video, manipulation and transformation of “lost-and-found objects” in sculptures, jewelry (some of them have been used for the film series I Medici, the Masters of Florence) and artist books. Her artistic production encompasses the monumental fresco, small scenographies, Teatro d’Artista and Show/Performance. Her work often develops in thematic cycles that involve an identification process (Eros/Thanatos; Eurydice; Narcissus; The Lady and the Unicorn; Heloise and Abelard; Saint George and the Princess; The Dioscuri; The Angels of the Annunciations; The Musicians of Gesualdo) sometimes with the staging of her own body.

For more than twenty years she has devoted herself to a work of creation and research on the composer Carlo Gesualdo, a contribution that elevates the theme of the Prince of Venosa to mythic proportions, with the 2002 production of paintings for the Arch of the Church of the Addolorata in the city of Gesualdo of which she is an honorary citizen.

The artist is also committed to didactic and research activity as a participant in conferences and publications (Lecturer at the Centre National d’Art et de Culture Georges Pompidou, Paris, 1977-2009).

www.kathy-toma.com

Nov 30, 2016
12:00 PM
Dec 09, 2016
12:00 PM

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