Yunjie Tong: “Concurrent near infrared spectroscopy (NIRS) and functional MRI studies on human brain function and physiology”
12:15 〜 13:00
CiNet 1F Conference Room
Mclean Imaging Center, McLean Hospital, Belmont, MA
Department of Psychiatry, Harvard Medical School, Boston, MA
Host PI : Okito Yamashita
Functional MRI (fMRI) and near infrared spectroscopy (NIRS) are two non-invasive imaging modalities commonly used to study human brain function. However, they can only measure neuronal activation indirectly through neurovascular coupling. Other non-neuronal physiological fluctuations, such as respiration, can also influence their signals. In this talk, I will introduce a novel method which identifies a physiological low frequency oscillation (LFO) in fMRI signals through concurrent fMRI/NIRS study. We have demonstrated that this LFO is a dynamic signal which travels with the blood throughout the brain Moreover, we found that the same LFO in the periphery. These findings indicated the systemic feature of this wave and its potential extracerebral origin. To put our discoveries into practical application, we have designed methods to convert this “confounding” systemic signal into a useful perfusion biomarker. For examples, using the LFO and its temporal shifts, dynamic cerebral blood flow map has been obtained from regular resting state fMRI scans, which allows simultaneous assessment of functional networks and perfusion. Furthermore, novel methods have been developed based on the same analytical principle to: 1) track cardiac pulsation wave in the fMRI data; 2) denoise fMRI data and 3) assess cerebral blood flow recovery in Moyamoya patients after surgery.
The Friday Lunch Seminar is CiNet's main regular meeting series, held every week at 12:15 in the beautiful main lecture theatre on the ground floor at CiNet. The talks are typically 40mins long and orientated towards an inter-disciplinary audience. They are informal, social, and most people bring their own lunch to eat during the talk. They are open to anyone who is feeling curious and wants to come, regardless of where you work.