Purdon S E, Klein S, Flor-Henry P
Department of Psychiatry, University of Alberta, Edmonton, Canada.
J Int Neuropsychol Soc. 2001 Sep;7(6):703-9. doi: 10.1017/s1355617701766064.
Gender specific discrepancies on psychometric examination are often interpreted to reflect static differences in cerebral hemisphere specialization, but dynamic alterations relating to circulating gonadal hormones may also be relevant after puberty. The often cited inference of a right hemisphere advantage in males and left hemisphere advantage in females derived from small but reliable differences on spatial tasks and verbal tasks, for example, may to some extent relate to gender-specific differences in circulating gonadal hormones. Performance fluctuations on other higher order cognitive tasks through the menstrual cycle tend to support a temporal association between alterations in cerebral laterality and hormone fluctuations. A potential left hemisphere advantage after menstruation when estrogen and progesterone levels are high in contrast to a right hemisphere advantage at menstruation when estrogen and progesterone levels are low has also received support from shifts in visual field perception. The present investigation continues this line of work by measurement of prospective changes in unirhinal olfactory acuity in the menstrual, ovulatory, and midluteal phases of the menstrual cycle in 11 healthy women who agreed to blood assays of estradiol and progesterone prior to completing a modified version of the Connecticut Chemosensory Perception Exam (CCPE). The CCPE detection of n-butanol showed a clear pattern of changes over the menstrual cycle marked by an asymmetry favoring the right nostril during menstruation when estradiol and progesterone levels were low, an asymmetry favoring the left nostril during ovulation when estradiol levels were high and progresterone levels were low, and an absence of asymmetry during the midluteal phase when estradiol levels decreased and progesterone levels increased. Preliminary correlation analyses revealed a potential competitive influence of estradiol and progesterone on this apparent shift in cerebral laterality. There is thus sufficient evidence to conclude that dynamic changes in relative cerebral hemisphere advantages have a temporal relation to fluctuations in circulating gonadal hormones and to suggest the value of additional investigation of more specific causal relations.
心理测量学检查中的性别差异通常被解释为反映大脑半球特化的静态差异，但青春期后与循环性腺激素相关的动态变化也可能起作用。例如，常被引用的男性右半球优势和女性左半球优势的推断，源于空间任务和语言任务上虽小但可靠的差异，这在一定程度上可能与循环性腺激素的性别差异有关。月经周期中其他高阶认知任务的表现波动倾向于支持大脑偏侧性改变与激素波动之间的时间关联。与雌激素和孕酮水平低的月经期右半球优势相反，雌激素和孕酮水平高的月经后期潜在的左半球优势也得到了视野感知变化的支持。本研究通过测量11名健康女性在月经周期的月经期、排卵期和黄体中期单鼻孔嗅觉敏锐度的前瞻性变化来延续这一工作思路，这些女性在完成改良版的康涅狄格化学感觉知觉测试（CCPE）之前同意进行雌二醇和孕酮的血液检测。CCPE对正丁醇的检测显示出在月经周期中明显的变化模式，其特征是在雌激素和孕酮水平低的月经期，右鼻孔具有不对称优势；在雌激素水平高而孕酮水平低的排卵期，左鼻孔具有不对称优势；在雌激素水平下降而孕酮水平上升的黄体中期，不存在不对称性。初步相关性分析揭示了雌二醇和孕酮对这种明显的大脑偏侧性变化可能存在竞争影响。因此，有足够的证据得出结论，相对大脑半球优势的动态变化与循环性腺激素的波动存在时间关系，并表明进一步研究更具体因果关系的价值。
