Laboratório de Estudos de Memória, Departamento de Fisiologia, Universidade Federal do Rio Grande do Norte, Natal, Brazil.
Brain Cogn. 2010 Nov;74(2):145-51. doi: 10.1016/j.bandc.2010.07.012. Epub 2010 Aug 19.
Studies usually show better spatial learning in males and stronger emotional memory in females. Spatial memory differences could relate to diverse strategies, while dissimilar stress reactions could cause emotional memory differences. We compared male and female rats in two emotional (classical emotional conditioning and aversive discrimination memory) and two emotionally "neutral" tasks: (1) plus-maze discriminative avoidance, containing two open and two enclosed arms, one of which presenting aversive stimuli (light/noise). No differences were found in learning, retrieving, or basal emotional levels, while only male rats presented extinction of the task; (2) contextual fear conditioning--a cage was paired to mild foot shocks. Upon reexposure, freezing behavior was decreased in females; (3) spontaneous alternation--the animals were expected to alternate among the arms of a four-arm maze. No differences between genders were found and (4) open-field habituation was addressed in an arena which the rats were allowed to explore for 10 min. Habituation was similar between genders. Differences were found only in tasks with strong emotional contexts, where different fear responses and stress effects could be determinant. The lack of extinction of discriminative avoidance by females points out to stronger consolidation and/or impaired extinction of aversive memories.
研究通常表明男性在空间学习方面表现更好，而女性在情绪记忆方面更强。空间记忆差异可能与不同的策略有关，而不同的应激反应可能导致情绪记忆差异。我们比较了雄性和雌性大鼠在两个情绪任务（经典情绪条件反射和厌恶辨别记忆）和两个情绪“中性”任务中的表现：（1）加迷宫辨别回避，包含两个开放臂和两个封闭臂，其中一个臂呈现厌恶刺激（光/噪音）。在学习、检索或基础情绪水平方面没有发现差异，而只有雄性大鼠表现出任务的消退；（2）情境性恐惧条件反射——一个笼子与轻度脚震配对。重新暴露时，雌性动物的冻结行为减少；（3）自发交替——期望动物在一个四臂迷宫的臂之间交替。在性别之间没有发现差异，（4）在一个允许大鼠探索 10 分钟的竞技场中进行了开阔场地习惯化。男女之间的习惯化相似。只有在具有强烈情绪背景的任务中才发现了差异，在这些任务中，不同的恐惧反应和应激效应可能是决定性的。雌性大鼠对辨别回避的消退缺乏反应表明对厌恶记忆的巩固和/或消退受损。
