Abstract: | We have systematically and simultaneously recorded vesical pressure and maximum urethral closure pressure (MUCP) in 109 women consulting for urinary incontinence over an extended period of time. During the recording, we asked them to peform a mental calculation (MC) test and other tests designed to induce an effort of voluntary attention. We found a significant increase in MUCP during the MC. At rest, 57 women displayed urethral pressure variations (UPV) higher than 15 cm H2O. MC inhibited UPV in 80% of these cases. Such variations have never yet been reported. The effect of MC can be compared to an orienting reaction, which normally increases the sympathetic tonus. The role of the smooth and striated muscle fibers of the urethra, in the observed changes in urethral pressure, is discussed in light of the literature data. |