动物,包括人类,依靠上下文信息来解释模棱两可的刺激。受损的上下文处理是几种神经精神疾病的标志,包括精神分裂症,自闭症谱系障碍,创伤后应激障碍,和上瘾。虽然这些疾病的患病率和表现存在性别差异,情境处理中潜在的性别差异仍然不确定。这里,我们研究了对线索诱发的奖励寻求及其神经相关因素的上下文控制的性别差异,在老鼠雄性和雌性大鼠在双向场合设置准备中进行了训练,其中两个听觉奖励预测线索的有效性由存在告知,或缺席,视觉上下文特征(LIGHT:X+/DARK:X-/LIGHT:Y-/DARK:Y+)。女性对线索引起的奖励寻求的情境控制明显较慢。然而,一旦建立,在雌性大鼠中,对行为的上下文控制更加强大;它显示出会话内变异性较小(先前奖励的影响较小)和对急性压力的抵抗力更大。与男性相比,女性获得的这种出色的上下文控制伴随着眶额皮质(OFC)的激活增加。严重的,这些行为和神经性别差异是特定于上下文调制过程的,而不是在简单的情况下观察到的,上下文无关,奖励预测任务。这些结果表明,在获取提示奖励寻求的上下文调制中,获取速度与表现的鲁棒性之间存在性别偏见。沿快速学习↔稳定性能连续体的性别分布不同可能反映了OFC的参与程度不同,可能会影响我们对精神疾病中性别差异的理解。
Animals, including humans, rely on contextual information to interpret ambiguous stimuli. Impaired context processing is a hallmark of several neuropsychiatric disorders, including schizophrenia, autism spectrum disorders, post-traumatic stress disorder, and addiction. While sex differences in the prevalence and manifestations of these disorders are well established, potential sex differences in context processing remain uncertain. Here, we examined sex differences in the contextual control over cue-evoked reward seeking and its neural correlates, in rats. Male and female rats were trained in a bidirectional occasion-setting preparation in which the validity of two auditory reward-predictive cues was informed by the presence, or absence, of a visual contextual feature (LIGHT: X+/DARK: X-/LIGHT: Y-/DARK: Y+). Females were significantly slower to acquire contextual control over cue-evoked reward seeking. However, once established, the contextual control over behavior was more robust in female rats; it showed less within-session variability (less influence of prior reward) and greater resistance to acute stress. This superior contextual control achieved by females was accompanied by an increased activation of the orbitofrontal cortex (OFC) compared to males. Critically, these behavioral and neural sex differences were specific to the contextual modulation process and not observed in simple, context-independent, reward prediction tasks. These results indicate a sex-biased trade-off between the speed of acquisition and the robustness of performance in the contextual modulation of cued reward seeking. The different distribution of sexes along the fast learning ↔ steady performance continuum might reflect different levels of engagement of the OFC, and might have implications for our understanding of sex differences in psychiatric disorders.