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Program in NHP Neuroimaging. Calum Avison. Overview. Rationale Biophysics Biology / behavior Facilities / Capabilities Imaging Support Equipment Staff Projects DTI Tractography Validation Rhesus (3T) - neurodevelopmental consequences of cocaine exposure in utero
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Program in NHP Neuroimaging Calum Avison
Overview • Rationale • Biophysics • Biology / behavior • Facilities / Capabilities • Imaging • Support Equipment • Staff • Projects • DTI Tractography Validation • Rhesus (3T) - neurodevelopmental consequences of cocaine exposure in utero • Squirrel monkey (9.4T) - neural correlates of tactile illusion / correlation with optical imaging and electrophysiology
Structural Homology? Functional Homology? NHP Rationale - Biology
Prenatal Cocaine Exposure in Rhesus • Developmental neurobiology • PNCE behavioral/cognitive impairment? • Structure • Functional circuitry • Pre-/post-synaptic defects in neurotransmission • Methodology • mPET mapping of receptors, neurotransmitter release • High resolution structural MRI + VBM • High resolution DTI • fMRI responses to pre-/post-synaptic agents • Co-registration
Co-registered (ABA) PET/MR images of Rhesus Monkey T1-weighted MR image acquired on a human 3T scanner Summed image from a 3-hr acquisition after 4.9 mCi injection of the D2 receptor ligand [F-18]fallypride
p_2_22 p_2_31 p_2_27 p_2_17 HARDI / FORECAST - NHP (92 directions) 1.5 mm isotropic 2ch FLEX-M coil SENSE, R=1.5
p_2_31 p_2_27 p_2_22 p_2_17 HARDI / FORECAST - NHP (92 directions) 0.8 mm isotropic 2ch FLEX-M coil SENSE
Implementation on Intera Achieva 3T • Humans - 2 mm isotropic; 32, 92 directions • Neonatal development • Normal and abnormal • Developmental abnormalities • Correlation with ss-fMRI (structure begets function) • NHPs - 0.8 mm isotropic; 92 directions • Validation of HAR diffusion methods • Structural homology (y/n?) with humans • y Model of human brain • n Brain evolution • Effects of prenatal cocaine exposure
HARDI / FORECAST Human vs NHP (92 directions) p_2_17 h_03
HARDI / FORECAST Human vs NHP (92 directions) p_2_22 h_09
HARDI / FORECAST Human vs NHP (92 directions) p_2_25 h_10
NHP at 3T • 2ch FLEX-M coil • SENSE
Coregistration (Overlay) functional 2D anatomic Coregistration using gyri information to match 2D and 3D Draw Volumes-of-interest • Look at timecourse information for each VOI • - Statistics: GLM, ROI analysis
Volumes-of-interest supragenual anterior cingulate cortex (ACC1) Caudate head (Divided into RH and LH) Subgenual anterior cingulate cortex (ACC2) Putamen (Divided into RH and LH)
BrainVoyager Capability General Linear Model Graph and Table of beta weight values Can apply statistics and obtain timecourse of only significantly activated voxels. (above: TC of significantly activated voxels of all six determined volumes-of-interest. 1.0 mg Cocaine administered at volume 200.)