Laboratory for Brain Connectomics Imaging
Takuya HayashiM.D., Ph.D.
- Location：Kobe / MI R&D Center Building
- E-mail：takuya.hayashi[at]riken.jpPlease replace [at] with @.
- Lab Website
Dissecting brain function, architecture and connectivity – brain connectome
We are focusing on visualizing and understanding organization of brain function, structure, connectivity (brain connectome) using neuroimaging techniques such as MRI and PET. We develop various neuroimaging techniques such as image acquisition, analysis, and database. Imaging techniques developed thus are expected to help early diagnosis and treatment of intractable brain disease.
Diffusion weighted MRI is one of recently developed imaging techniques. This imaging allows to show the contrast depending on the diffusion motion of water molecule in tissue. In the brain, the water molecule diffusion motion is strongly limited by the neuronal axon membranes, therefore diffusion MRI has been expected to visualize properties of axon density and orientation. We have established a technique that visualize cortical distribution of such neurite properties by using a physiological model for neurites in combination with cortical mapping technique (Fukutomi et al., 2018). This technique allowed us to separately map density of cortical neurite, as well as that of myelin, which surrounding neurites (Fig 01). This may be potentially useful for diagnosis of neurite disease (e.g. neurodegenerative disease) and myelin disease (e.g. multiple sclerosis) in clinics.
Smokers are often patient for short-term abstinence but hardly quit smoking. We identified aberrant neuronal circuits in addiction revealed by functional MRI. We have found that the abnormal circuit between the orbitofrontal and the dorsolateral prefrontal cortex underlies the mechanism of craving for smoking in heavy smokers (Fig 02). The orbitofrontal cortex is involved in valuation of smoking behavior, while the dorsolateral prefrontal cortex in its contextual aspects such as availability or abstinence). In addition, the craving response was inhibited by transcranial repetitive magnetic stimulation targeted on the dorsolateral prefrontal cortex, suggesting potential use for medical treatment. The paper was published in the Proceedings of National Academy of Sciences, USA (PNAS), and selected as a highlight of the corresponding issue.
Marmoset is an experimental animal recently attracting neuroscientists and medical researchers as it can be bred efficiently and combined with genetic manipulation. We are focusing on brain mechanisms of ‘sociality’, one of higher-level cognitive functions in primates. Serotonergic neurotransmitter system is known to be associated with treatment of depression in human. We identified that marmoset has a similar serotonergic brain system like in humans, as shown by PET imaging. We also found the three big factors of marmoset social behaviors – aggressiveness, anxiety and friendliness – are represented in distinctive loci in the medial wall of cerebral cortices (Yokoyama et al Cerebral Cortex 2013) (Fig 03). In human, the medial wall of cerebral cortices is known to process self-others relationship and emotions. Therefore, the marmoset may be useful model for understanding sociality and developing sensitive imaging techniques, hopefully contributing to understand the mechanism of depression, autism etc.
- Visualization of brain connectomics
- Reorganization of brain network in regeneration
- Reorganization of brain network in plasticity
- Sociality, brain network and neurotransmitter
Main Publications List
Fukutomi H, Glasser MF, Zhang H, et al.
Neurite imaging reveals microstructural variations in human cerebral cortical gray matter.
Neuroimage S1053-8119(18). 30105-8 (2018) doi : 10.1016/j.neuroimage.2018.02.017
Morizane A, Kikuchi T, Hayashi T, et al.
MHC matching improves engraftment of iPSC-derived neurons in non-human primates.
Nature Communication 8. 385 (2017) doi: 10.1038/s41467-017-00926-5
Kikuchi T, Morizane A, Doi D, et al.
Human iPS cell-derived dopaminergic neurons function in a primate Parkinson’s disease model.
Nature 548. 592–596 (2017) doi: 10.1038/nature23664
Takenobu Y, Hayashi T, Moriwaki H, et al.
Motor recovery and microstructural change in rubro-spinal tract in subcortical stroke.
NeuroImage: Clinical14. 201-208 (2014) doi: 10.1016/j.nicl.2013.12.003
Yokoyama C, Kawasaki A, Hayashi T, et al.
Linkage Between the Midline Cortical Serotonergic System and Social Behavior Traits: Positron Emission Tomography Studies of Common Marmosets.
Cerebral Cortex 23(9). 2136-2145 (2013) doi: 10.1093/cercor/bhs196
Hayashi T, Ko JH, Strafella AP, et al.
Dorsolateral prefrontal and orbitofrontal cortex interactions during self-control of cigarette craving.
Proceedings of the National Academy of Sciences of the United States of America 110(11). 4422-4427 (2013) doi: 10.1073/pnas.1212185110
Hayashi T, Shimazawa M, Watabe H, et al.
Kinetics of neurodegeneration based on a risk-related biomarker in animal model of glaucoma.
Molecular Neurodegeneration 64(8), 594-601 (2010). 18(8). 4 (2013) doi: 10.1186/1750-1326-8-4
Hayashi T, Wakao S, Kitada M, et al.
Autologous mesenchymal stem cell-derived dopaminergic neurons function in parkinsonian macaques.
Journal of Clinical Investigation 123(1). 272-284 (2013) doi: 10.1172/JCI62516
Ikoma Y, Watabe H, Hayashi T, et al.
Measurement of density and affinity for dopamine D(2) receptors by a single positron emission tomography scan with multiple injections of [(11)C]raclopride.
Journal of Cerebral Blood Flow & Metabolism 30(3) 663-673 (2010) doi: 10.1038/jcbfm.2009.239
Takagi Y, Takahashi J, Saiki H, et al.
Dopaminergic neurons generated from monkey embryonic stem cells function in a Parkinson primate model.
Journal of Clinical Investigation 115(1). 102-109 (2005) doi: 10.1172/JCI21137