抄録
This study was performed to examine the effects of mental arithmetic (MA) on cerebral blood flow (CBF) . We recorded the blood flow velocity before, during and after mental arithmetic in the bilateral internal carotid arteries (ICA) and vertebral arteries (VA) simultaneously and continuously in nine healthy males (25.8±7.2 y.o.) . The subjects performed MA for 30-60 seconds. The mean values of blood flow velocity (BFV) were calculated for each pulse using an FFT-analyzer.
We observed BFV in 24 ICAs and 9 VAs in all of the 9 subjects. During MA in comparison with the period before MA, BFV in the 10 of ICAs and the 3 of VAs increased significantly, however BFV in the other 3 of ICAs decreased significantly and the rest 11 of ICAs was unchanged. The number of increases was significantly higher than that of decreases and no changes. After MA compared with the period during MA, BFV in the 3 ICAs and the 3 VAs decreased significantly, however BFV in one ICA increased significantly and the rest of 20 ICAs was unchanged. Also the blood pressure and heart rate were unchanged during MA.
In summary, our study identified and documented statistically significant changes in cerebral blood flow velocity during MA. And it was suggested that some other factors, such as mental state, have influence on cerebral blood flow velocity during MA.
