My research activity focuses broadly on the
development of non-invasive optical techniques and application in the
neurosciences, neurology, and brain health. Near-infrared spectroscopy (NIRS)
uses light in the visible and near-infrared spectral regions to quantify absolute or relative changes in hemoglobin
concentration in biological tissues. I began working with NIRS in the early
1990s, when the field was just emerging, and I have contributed to the
development of instruments now commercially available and widely used. As a
pioneer in the field, I have made substantial contributions to the modeling and
testing of the diffusion theory to describe light propagation in turbid media.
As an experimentalist interested in biomedical applications, I have tested the
technique for several medical applications, including detection of breast
cancer, assessment of peripheral vascular disease, non-invasive blood glucose
monitoring, brain oxygenation monitoring, brain functional activity, and
neurovascular coupling investigation.

Since early 2000, I have devoted part of my time to
the development of a sophisticated near-infrared spectroscopy device (FDNIRS-DCS)
that can determine brain health in infants at the bedside by quantifying
regional hemoglobin oxygenation, cerebral blood volume, cerebral blood flow,
and oxygen consumption in the neonates brain. Such a device shows potential
for detecting brain tissue compromise before the development of irreversible
structural damage, thus allowing timely and specific intervention. I have
collected data from 500+ infants and demonstrated this systems ability to
follow normal brain development and detect brain damage. In collaboration with
medical doctors I am now studying the effect of therapies such as controlled
hypothermia on cerebral metabolism to establish NIRS as a potential tool to
guide and optimize individual care, and, in collaboration with ISS Inc., I have developed a commercial version of our FDNIRS-DCS device. 

At the same time,
in the past 20 years I have developed fNIRS technology for functional brain
studies and to investigate neurovascular coupling. I have designed and
performed a number of multimodal studies using fNIRS in conjunction with fMRI,
MEG, and EEG in humans and small animal models. This work has helped to
establish NIRS in the field of neuroscience.