Hetrick W P, Sandman C A, Bunney W E, Jin Y, Potkin S G, White M H
Department of Psychiatry and Human Behavior University of California, Irvine, USA.
Biol Psychiatry. 1996 Jan 1;39(1):51-8. doi: 10.1016/0006-3223(95)00067-4.
Central nervous system (CNS) inhibitory mechanisms hypothesized to "gate" repetitive sensory inputs have been implicated in the pathology of schizophrenia. The present study investigated gender differences in inhibitory gating of evoked brain responses to repeated stimuli in normal subjects (30 women and 30 men) using an auditory conditioning-testing paradigm. Pairs of click stimuli (S1 and S2) were presented with a 0.5 s intrapair and a 10 s interpair interval. The amplitudes and latencies of the P50, N100, P180 components of the auditory evoked response to the conditioning (S1) and test response (S2) were measured, and the gating ratios were computed (T/C ratio = S2/S1 * 100). The amplitudes to S1 were not significantly different between men and women at P50, N100, or P180. However, women had significantly higher amplitudes to S2 at P50 (p = 0.03) and N100 (p = 0.04). The T/C ratios for women were higher (i.e., less suppression of response to S2) for P50 (p = 0.08) and N100 (p = 0.04) compared to men. The results suggested that differences in auditory gating between men and women were not due to biological differences in the P50 and N100 generators but possibly to differential influence of inhibitory mechanisms acting on the generator substrates of these evoked responses.
中枢神经系统（CNS）的抑制机制被认为可以“调节”重复性感觉输入，这一机制与精神分裂症的病理过程有关。本研究使用听觉条件化测试范式，调查了正常受试者（30名女性和30名男性）对重复刺激诱发的脑反应抑制调节中的性别差异。成对的点击刺激（S1和S2）以0.5秒的配对内间隔和10秒的配对间间隔呈现。测量了对条件刺激（S1）和测试刺激（S2）的听觉诱发电位中P50、N100、P180成分的振幅和潜伏期，并计算了调节比率（T/C比率 = S2/S1 * 100）。在P50、N100或P180时，男性和女性对S1的振幅没有显著差异。然而，女性在P50（p = 0.03）和N100（p = 0.04）时对S2的振幅显著更高。与男性相比，女性在P50（p = 0.08）和N100（p = 0.04）时的T/C比率更高（即对S2反应的抑制较少）。结果表明，男性和女性在听觉调节上的差异并非由于P50和N100发生器的生物学差异，而是可能由于作用于这些诱发电位发生器底物的抑制机制的不同影响。
