Seiji Ogawa, CiNet Advisor
Dr. Seiji Ogawa and his collaborators discovered the BOLD effect, the fundamental principle underlying functional magnetic resonance imaging (functional MRI; fMRI) and led one of the first studies that successfully demonstrated the viability of fMRI as a brain activity measurement technique. BOLD stands for “blood oxygenation level dependent” and has the effect of changing the MRI signal according to the oxygen saturation level of the blood.
The hemoglobin in red blood cells has different magnetic properties depending on whether it is bound to oxygen or not. In other words, the amount of hemoglobin not bound to oxygen (i.e., oxygen saturation level) changes the MRI signal inside and around blood vessels. In the late 1980s, while imaging animal brains with MRI, Dr. Ogawa observed that a thread-like low signal appeared in the brain depending on the physiological state of the animal and further noticed that the signal change originated from hemoglobin in red blood cells. Dr. Ogawa had previously employed magnetic resonance (NMR) to study the molecular structure and function of hemoglobin, and this experience led to the discovery of the BOLD effect. He was convinced that the BOLD effect could be used to measure brain activity, and in 1992, together with colleagues, he succeeded in identifying brain regions that were activated during the performance of a task using fMRI.
Before the discovery the BOLD effect, the primary method to measure brain activity non-invasively consisted of collecting electrical signals from the scalp using a technique called electroencephalogram (EEG). One of the drawbacks of EEG, though, is that it is difficult to precisely identify the location of the sources of the measured brain activity. In addition, although other techniques such as positron emission tomography (PET) are capable of recording whole-brain activity, their use has been limited by the need to use radioisotopes. Functional MRI addresses these limitations by allowing researchers to noninvasively and repeatedly measure activity in the living brain and has played a fundamental role in advancing our understanding of human brain function.
Functional MRI have been used not only to identify brain regions recruited during the performance of different tasks but also to elucidate how these regions connect to one another to form networks. It has been heavily employed in clinical applications, such as in determining target sites before an operation and in unraveling brain networks that may serve to diagnose mental disorders in the future, but also in many other fields including neuroscience, psychology, cognitive science, and social science. Functional MRI has also made significant contributions to the advancement of AI technology by means of the so-called decoding technology, a technique employed to translate human brain information into actions and labels, as well as via the collection and the sharing of large amounts of brain activity data that may serve to guide the developments of AI systems in the future. Furthermore, fMRI research has led to technological innovations such as ultra-high magnetic fields in MRI systems and improvements in image analysis technology. Dr. Ogawa has received numerous prestigious awards for his pioneering contributions, including the Japan International Prize and the Gardner International Prize.
<Honors and Awards>
1967 Eastman Kodak Award in Chemistry for PhD student
1995 GOLD Medal Award from Society for Magnetic Resonance in Medicine
1996 Biological Physics Prize from The American Physical Society
1997 Fellow, International Society for Magnetic Resonance in Medicine
1998 Nakayama Prize from Nakayama Foundation for Human Science, Japan
1999 Asahi Prize from Asahi-Shinbun Cultural Foundation, Japan
2000 Member, Institute of Medicine (IOM) of National Academy of Sciences, USA
2003 Japan International Prize 2003 from Japan Science Technology Foundation
2003 Gairdner International Award from Gairdner Foundation, Canada
2004 Honorary Member, Japanese Society for Magnetic Resonance in Medicine
2004 Honorary Member, Japanese Society for Nuclear Magnetic Resonance
2005 Honorary Member, National Magnetic Resonance Society of India
2005 Foreign Fellow, The National Academy of Sciences of India
2007 ISMAR Prize from International Society of Magnetic Resonance
2008 Honorary Doctor of Science, S. Gandi Post-graduate University for Medical, Lucknow, Science India
2008 Olli V. Lounasmaa Memorial Prize, Helsinki University of Technology, Finland.
2009 Named as a Thomson-Reuter Citation Laureate in Medicine
2011 Linus Pauling Medal & Lectureship from Stanford University Medical School
2011 Mansfield Lecturer at ISMRM 2011 Society Meeting, Montreal
2011-2015 Fellow, National Institute Radiological Sciences (NIRS) of Japan
2014 Tateishi Grand Prize, Tateishi Science and Technology Foundation, Japan
2016 Honorary Fellow, National Institute for Quantum and Radiological Science and Technology, Japan
2017 Keio Medical Science Prize
2018 Prime Minister’s Prize, The Japan Medical Research and Development Grand Prize
2020 Distinguished Honorary Professor, Osaka University