Ishiwari Keita, King Christopher P, Martin Connor D, Tripi Jordan A, George Anthony M, Lamparelli Alexander C, Chitre Apurva, Polesskaya Oksana, Richards Jerry B, Woods Leah C Solberg, Gancarz Amy, Palmer Abraham A, Dietz David M, Mitchell Suzanne H, Meyer Paul J
Clinical and Research Institute on Addictions, University at Buffalo, Buffalo, NY, USA.
Department of Pharmacology and Toxicology, University at Buffalo, Buffalo, NY, USA.
bioRxiv. 2023 Aug 1:2023.06.30.547228. doi: 10.1101/2023.06.30.547228.
Organisms must regulate their behavior flexibly in the face of environmental challenges. Failure can lead to a host of maladaptive behavioral traits associated with a range of neuropsychiatric disorders, including attention deficit hyperactivity disorder, autism, and substance use disorders. This maladaptive dysregulation of behavior is influenced by genetic and environmental factors. For example, environmental enrichment produces beneficial neurobehavioral effects in animal models of such disorders. The present study determined the effects of environmental enrichment on a range of measures related to behavioral regulation using a large cohort of male, outbred heterogeneous stock (HS) rats as subjects to mimic the genetic variability found in the human population. Subjects were reared from late adolescence onwards either in pairs in standard housing with minimal enrichment (n=200) or in groups of 16 in a highly enriched environment consisting of a large multi-level cage filled with toys, running wheels, and shelters (n=64). Rats were subjected to a battery of tests, including: (i) locomotor response to novelty, (iI) light reinforcement, (iii) social reinforcement, (iv) reaction time, (v) a patch-depletion foraging test, (vi) Pavlovian conditioned approach, (vii) conditioned reinforcement, and (viii) cocaine conditioned cue preference. Results indicated that rats housed in the enriched environment were able to filter out irrelevant stimuli more effectively and thereby regulate their behavior more efficiently than standard-housing rats. The dramatic impact of environmental enrichment suggests that behavioral studies using standard housing conditions may not generalize to more complex environments that may be more ethologically relevant.
面对环境挑战时，生物体必须灵活调节其行为。调节失败可能导致一系列与多种神经精神疾病相关的适应不良行为特征，包括注意力缺陷多动障碍、自闭症和物质使用障碍。这种行为的适应不良调节受到遗传和环境因素的影响。例如，环境丰富化在这类疾病的动物模型中产生有益的神经行为效应。本研究以一大群雄性远交群（HS）大鼠为对象，确定环境丰富化对一系列与行为调节相关指标的影响，以模拟人类群体中发现的遗传变异性。从青春期后期开始，将实验对象分别饲养，一组200只成对饲养在标准环境中，环境丰富度最低；另一组64只成群饲养在高度丰富的环境中，该环境由一个装满玩具、跑轮和庇护所的大型多层笼子组成。对大鼠进行了一系列测试，包括：（i）对新奇事物的运动反应，（ii）光强化，（iii）社会强化，（iv）反应时间，（v）斑块耗尽觅食测试，（vi）巴甫洛夫条件性接近，（vii）条件性强化，以及（viii）可卡因条件性线索偏好。结果表明，与饲养在标准环境中的大鼠相比，饲养在丰富环境中的大鼠能够更有效地过滤掉无关刺激，从而更有效地调节其行为。环境丰富化的显著影响表明，使用标准饲养条件的行为研究可能无法推广到更符合生态学意义的更复杂环境中。
