R. Todd Constable, PhD

Contact

Address:
Yale University, School of Medicine
Magnetic Resonance Research Center
TAC, N132, 300 Cedar Street
New Haven, Connecticut 06520-8043
United States

Email: todd.constable@yale.edu
Telephone: (203) 737-2768
Fax: (203) 785-6534

Education:

PhD, Medical Biophysics, University of Toronto, 1990

Please click here for Curriculum Vitae

Research Interests:

Magnetic Resonance Imaging (MRI) can provide information on both structure and function. Research in my lab focuses on the development of MRI techniques to provide functional information and quantitative information in addition to high quality pictures of anatomy and the application of new methods to answer fundamental questions in basic science and medicine.

We have efforts underway to examine the relationship between the increment in the functional MR signal measured during a task (cognitive or sensory/motor) and the influence of baseline brain activity on this increment. We have research projects aimed at understanding negative blood oxygenation level dependent signal changes observed in certain cognitive tasks and the relationship between simultaneously recorded surface EEG signals and fMRI, in order to better understand the relationship between the fMRI signal changes measured and brain function. Clinical applications include localization of inter-ictal electrical discharges in the brains of epilepsy patients, assessing normal vs. abnormal cortical connectivity, and functional mapping for neurosurgical treatment planning. In more fundamental MR engineering projects, we are focused on developing novel MR imaging strategies for faster and more efficient parallel imaging.

My lab's current research centers on either technical development of new MRI methods, or functional brain imaging. In the former category, we are doing research aimed at not only quantifying fat in tissue but also developing MR methods that allow us to characterize the type of fat present; this may have important diagnostic consequences. We are also developing a new approach to MRI that uses novel higher order encoding gradients designed to be complementary to the spatial encoding provided by coils in order to perform highly efficient parallel image acquisitions. This approach is very general and could work with any pulse sequence. On the functional brain imaging side, we are interested in exploring the relationship between eeg signals and fMRI as measured via blood oxygenation, cerebral blood flow, or cerebral blood volume. We are also interested in functional connectivity as measured by fMRI and are developing novel contrast mechanisms based on connectivity data as well as exploring changes in connectivity as a function of baseline metabolic state and as a function of disease.

Selected Publications:

1. Meltzer J, Negishi M, Mayes LC, Constable RT, Individual differences in EEG theta and alpha dynamics during working memory correlate with fMRI responses across subjects, Clinical Neurophysiology, 118(11): 2419-2436, 2007.
2. Meltzer JA, Negishi M, Constable RT, Biphasic hemodynamic responses influence deactivation and may mask activation in block- design fMRI paradigms, Human Brain Mapping, 29(4): 385-399, 2007.
3. Meltzer JA, Zaveri HP, Goncharova II, Distasio MM, Papademetris X, Spencer SS, Spencer DD, Constable RT, Effects of working memory load on oscillatory power in human intracranial EEG, Cerebral Cortex, 18(8): 1843-1855, 2007.
4. Kim H., Pinus AB, Wang J, Murphy PS, Constable RT, On the application of chemical shift-based multipoint water-fat separation methods in balanced SSFP imaging, Magn. Reson. in Med., 58(2): 413-418, 2007.
5. Scouten A, Constable RT, Applications and limitations of whole-brain MAGIC VASO functional imaging. Magn Reson Med. 2007 Aug;58(2):306-15
6. Constable RT, Ment LR, Vohr BR, Kesler SR, Fulbright RK, Lacadie C, Delancy S, Katz KH, Schneider KC, Schafer RJ, Makuch RW, Reiss AR, Prematurely born children demonstrate white matter microstructural differences at 12 years of age, relative to term control subjects: an investigation of group and gender effects, Pediatrics 121(2): 306-316, 2008.
7. Scouten A, Constable RT, VASO-based calculations of CBV change: Accounting for the dynamics of CSF volume, Magn. Reson. Med., 59(2): 308-315, 2008.
8. Kim H, Booth CJ, Pinus AB, Chen P, Lee A, Qui M, Whitlock M, Murphy PS, Constable, RT, Induced hepatic fibrosis in rats: hepatic steatosis, macromolecule content, perfusion parameters, and their correlations – preliminary MR imaging in rats, Radiology, 247(3): 696-705, 2008.
9. Negishi M, Abildgaard M, Laufer I, Nixon T, Constable RT, An EEG (electroencephalogram) recording system with carbon wire electrodes for simultaneous EEG-fMRI (functional magnetic resonance imaging) recording. J. Neurosci. Methods, online ahead of print, 2008.
10. Ment LR, Constable RT, Injury and recovering in the developing brain: evidence from functional magnetic resonance imaging studies of the prematurely-born, Nature Clinical Practice Neurology, 3(10): 558-571, 2008.

For a further list of Constable's publications, please see Pubmed.

Current and Former Trainees

Undergraduate Summer Students:

1994 -  Joseph Yeh, Project Title: Phase Velocity Imaging in Cardiac MRI,
1995 -  Jessica Bloom Project Title: ROC Analysis of Methods in functional MRI,
1999 -  Johanna Zumer, Project Title: Functional MRI of the Hippocampus,
2000 -  Clifford Georges, Hippocampal Activation in Encoding and Retrieval,
2001 -  Ella Beyroya, fMRI of Language in Epilepsy,
2002 -  Samuel Wyche, Spatial Cueing and Exogenous Control over Covert Orienting,
2002 -  Nicole Hanick, fMRI Amplitude and Brain function, behavior, and Medication,
2002 -  Scott Degregorio, Partial volume, cortical thickness, fMRI activation amplitude,
2003 -  Nicole Hanick, fMRI Amplitude and Brain function, behavior, and Medication,
2004 -  Greg Fonzo, Configural vs. Elemental Associations: An EEG Investigation
2005 -  Geoffrey Schreiner: Imaging the Basilar Membrane
2005 -  Kendra Klang: Diffusion Tensor Imaging in Reading Disabled Children
2005 -  Jenelle Jindal: Subject Group Effects on fMRI of Language in Neurosurgery
2006 -  Kylene
2007 -  Kate Mullen: White matter microstructural abnormalities in preterm children
2007 -  Edmund Burke: Modality, Syntax and Semantics in preterm children

Graduate Students:

2001 -  2006, Jed Meltzer, PhD Student, Interdepartmental Neuroscience Program,
2003 -  2007, Amy Scouten, PhD Student, Biomedical Engineering
2005 -  2009, Yeunan Wang, PhD Student, Biomedical Engineering
2006 -  Current, Jason Stockman, PhD Student, Biomedical Engineering
2008 -  Current, L k Tam, PhD Student, Biomedical Engineering
2008 -  Current, Pelin Aksit, PhD Student, Biomedical Engineering

Supervision of residents of fellows research:

Neurosurgery Resident: Alexandre Carpentier from University of Paris VI, H'opital De La Salpetriere: Project Title: Functional MR Imaging of Language in Neurosurgical Planning, Oct. 98 - Oct. 99

Postdoctoral Fellows:

1996 - 1998, Matthew Robson: Project Title: Imaging image distortions in MRI – Cardiac and other applications. Now Faculty at Oxford University
1999 - 2002, Huairen Zeng. Project Title: Image Distortion and the PSF in MRI, Now at Vanderbilt University
2000 - 2002, Robert Astur:  Project title: The role of the hippocampus in mnemonic processes, Now Faculty at Institute of Living/Yale Psychiatry
2001 – 2002, Jess DiGiogianni:  Project title: Attention and Memory, Now teaching Faculty at Magdelan College
2001 - 2007, Robin Schafer:  Project title: Language, Linguistics and the impact of pathology
2001 - 2005, Vivien Rekkas:  Project title: Encoding and Retrieval Processes in Memory
2002 - Current, Michiro Negishi:  Project title: fMRI/EEG Fusion for Epileptogenic Tissue Localization
2002 - 2004, Alexander Pinus:  Project title: Dynamic shimming in fMRI, now in Medical School
2002 - Current, Maolin Qiu: Project title – Cerebral blood flow measured using MRI
2003 - Current, Jinghua Wang: Project title – Diffusion tensor imaging in the presence of brain lesions
2003 - 2008,  Rajeevan Nallakkandi: Project title – Development of analysis tools for fMRI
2004 - 2008,  Hyeonjin Kim: Project title – Development of noninvasive assessment of liver disease
2005 - Current, Ilan Laufer: Project title – Mismatched Negativity: EEG and fMRI correlates relating to top-down versus bottom up processing
2006 - Current, Jennifer Roth: Project Title – Negative BOLD and Cognitive Processing
2007 - Current, Roberto Martuzzi: Project Title – EEG/fMRI in Multi-sensory paradigms with modified baseline brain activity

BIOSTEP Mentor:
[BIOSTEP: Biomedical Summer Research Training and Enrichment Program for Minority Students]

Clifford Georges, from NYU, Summer 2000.
Ella Beyroya, from Mount Holyoke, Summer 2001.
Samuel Wyche, Emory, Summer 2002.
Greg Fonzo, Summer 2004.

External PhD Examiner: 

2001  Medical  College of Wisconsin, PhD Candidate: Vinai Roopchansingh, 
Title: Field compensation approaches in MRI
Biophysics Research Institute
Madison Wisconsin

1996  University of Toronto, PhD Candidate: Jonathon Bishop,
Dept. of Medical Biophysics Thesis Title: Techniques for Improved Time
and Data Efficiency in Fourier-encoded Magnetic Resonance Imaging,
Toronto, Ontario, Canada