Nemanic Sarah, Alvarado Maria C, Bachevalier Jocelyne
Department of Neurobiology and Anatomy, University of Texas Health Science Center, Houston, Texas 77030, USA.
J Neurosci. 2004 Feb 25;24(8):2013-26. doi: 10.1523/JNEUROSCI.3763-03.2004.
Recognition memory was assessed by submitting the same adult monkeys to visual paired comparison (VPC) with mixed delays (10-120 sec), followed by three consecutive versions of object-delayed nonmatching-to-sample (DNMS): increasing delays (10-600 sec), lengthened lists (3-10 objects), and intervening distractors in the delays (light at 10 sec, motor task at 30-600 sec, or context change at 600 sec). Four groups were tested: normal controls, monkeys with ibotenic acid lesions of the hippocampal formation (H), and monkeys with aspiration lesions of either the perirhinal (PRh) or parahippocampal (areas TH/TF) cortex. Group H was impaired on VPC at delays > or =60 sec but had difficulty on DNMS only at 600 sec delays with distraction. In group TH/TF, the VPC impairment emerged earlier (30 sec); yet, once the nonmatching rule was mastered, no significant change occurred on any DNMS condition. Only group PRh behaved congruently on VPC and DNMS, exhibiting a deficit at the easiest condition that worsened with increasing delays as well as in DNMS lengthened list and distraction conditions. These results led us to postulate that VPC and DNMS, as previously administered to monkeys, were not equivalent visual recognition memory probes. Specifically, we propose that, for VPC, because of passive (incidental) encoding, the animal's performance rests on both item familiarity and event recollection, whereas, for DNMS, because of active (purposeful) encoding, performance relies more on item familiarity. This proposal converges with current models postulating distinct, but interactive, mnemonic roles for the hippocampal and adjacent TH/TF regions.
通过让成年猴子进行混合延迟（10 - 120秒）的视觉配对比较（VPC）来评估识别记忆，随后进行连续三个版本的客体延迟非匹配样本任务（DNMS）：延迟增加（10 - 600秒）、列表加长（3 - 10个客体）以及延迟期间插入干扰物（10秒时为灯光，30 - 600秒时为运动任务，600秒时为情境变化）。测试了四组猴子：正常对照组、海马结构经鹅膏蕈氨酸损伤的猴子（H组）、嗅周皮层（PRh）或海马旁皮层（TH/TF区）经抽吸损伤的猴子。H组在延迟≥60秒的VPC任务中受损，但仅在600秒延迟且有干扰的DNMS任务中存在困难。在TH/TF组，VPC损伤出现得更早（30秒）；然而，一旦掌握了非匹配规则，在任何DNMS条件下都没有显著变化。只有PRh组在VPC和DNMS任务中的表现一致，在最容易的条件下就表现出缺陷，且随着延迟增加以及在DNMS列表加长和有干扰的条件下缺陷加剧。这些结果使我们推测，如先前用于猴子的VPC和DNMS并非等效的视觉识别记忆探测任务。具体而言，我们提出，对于VPC，由于被动（偶然）编码，动物的表现依赖于项目熟悉度和事件回忆，而对于DNMS，由于主动（有目的）编码，表现更多地依赖于项目熟悉度。这一推测与当前假设海马体和相邻的TH/TF区域具有不同但相互作用的记忆功能的模型相一致。
