Abstract
Our laboratory reported that facial skin blood flow may serve as a sensitive tool to assess an emotional status and that both prefrontal oxygenation (as index of regional cerebral blood flow) and facial skin blood flow decrease during positively-charged emotional stimulation, without changing hand skin blood flow and arterial pressure. However, the focal location of the prefrontal responses in concentration of oxygenated haemoglobin (Oxy-Hb) that correlate with peripheral autonomic reaction remained unknown. This study was undertaken using 22-channel near-infrared spectroscopy to reveal spatial distribution of the responses in Oxy-Hb within the prefrontal cortex (PFC) during emotionally-charged audiovisual stimulation. Pleasantly-charged (comedy) stimulation caused a substantial decrease of Oxy-Hb in all regions of the PFC in 18 subjects, especially in the rostroventral frontopolar PFC, whereas negatively-charged (horror) or neutral stimulation (landscape) exhibited a weaker decrease or insignificant change in the prefrontal Oxy-Hb. In the rostral parts of the dorsolateral and ventral frontopolar PFC, the oxygenation response during comedy stimulation exhibited the most significant positive correlation with the decrease in facial skin blood flow. Thus the rostral regions of the PFC play a role in recognition and regulation of positive emotion and may be linked with neurally-mediated vasoconstriction of facial skin blood vessels.
Highlights
The accumulating evidence suggests that the prefrontal cortex (PFC) is engaged in emotional recognition and processing as well as multiple functions such as attention, planning of motor act, and cognitive function
With two-channel near-infrared spectroscopy (NIRS) probes attached on the forehead, we have recently revealed that positively-charged audiovisual stimulation can evoke a reduction in prefrontal oxygenation, which may imply a decrease in regional cerebral blood flow (CBF) and thereby may reflect reduced activity in the PFC29
We have reported that facial skin blood flow decreases during positively-charged emotional stimulation and may serve as a more sensitive tool to assess an emotional or mood status in humans[28]
Summary
The accumulating evidence suggests that the prefrontal cortex (PFC) is engaged in emotional recognition and processing as well as multiple functions such as attention, planning of motor act, and cognitive function. Since the neuroimaging procedures accompany restriction of posture and body movement and probably impose stress more or less, such restriction may affect the emotional response, to a positively-charged stimulation As another problem of the imaging procedures, it is difficult to conduct real-time monitoring of prefrontal activity simultaneously with peripheral autonomic and circulatory changes, because the signal of blood oxygen level-dependent contrast has low time resolution and low signal to noise ratio. With two-channel NIRS probes attached on the forehead, we have recently revealed that positively-charged audiovisual stimulation can evoke a reduction in prefrontal oxygenation, which may imply a decrease in regional CBF and thereby may reflect reduced activity in the PFC29. The present study was undertaken (1) to measure the prefrontal Oxy-Hb responses on the different 22 locations using multichannel NIRS during emotionally-charged interventions and (2) to reveal the spatial distribution of the oxygenation responses in terms of both response magnitude and the extent of correlation with the changes in facial skin blood flow
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
