TRANSCRANIAL NEAR-INFRARED SPECTROSCOPY OF SMOKING BRAINS

We used a mobile wireless near-infrared sensor for the noninvasive recording of cerebral hemoglobin concentration changes during cigarette smoking. Each measurement included 5 min of rest, 5 min of smoking imitation, and 5 min of actual smoking. We observed significant effects of the tobacco smoking on temporal changes in the human brain at time scales ranging from 200ms to about 1min. The most reproducible effects were an increase of the heartbeat rate and a decrease in the heartbeat power spectral density during smoking. Significant but highly individual changes due to smoking were observed in temporal patterns of hemodynamic fluctuations in 5-50 s time scales. We have also found statistically significant slow increases in both oxy- and deoxy-hemoglobin concentrations during smoking.