Boston University.
J Cogn Neurosci. 1996 Summer;8(3):257-77. doi: 10.1162/jocn.1996.8.3.257.
The concepts of declarative memory and procedural memory have been used to distinguish two basic types of learning. A neural network model suggests how such memory processes work together as recognition learning, reinforcement learning, and sensorimotor learning take place during adaptive behaviors. To coordinate these processes, the hippocampal formation and cerebellum each contains circuits that learn to adaptively time their outputs. Within the model, hippocampal timing helps to maintain attention on motivationally salient goal objects during variable task-related delays, and cerebellar timing controls the release of conditioned responses. This property is part of the model's description of how cognitive-emotional interactions focus attention on motivationally valued cues, and how this process breaks down due to hippocampal ablation. The model suggests that the hippocampal mechanisms that help to rapidly draw attention to salient cues could prematurely release motor commands were not the release of these commands adaptively timed by the cerebellum. The model hippocampal system modulates cortical recognition learning without actually encoding the representational information that the cortex encodes. These properties avoid the difficulties faced by several models that propose a direct hippocampal role in recognition learning. Learning within the model hippocampal system controls adaptive timing and spatial orientation. Model properties hereby clarify how hippocampal ablations cause amnesic symptoms and difficulties with tasks which combine task delays, novelty detection, and attention toward goal objects amid distractions. When these model recognition, reinforcement, sensorimotor, and timing processes work together, they suggest how the brain can accomplish conditioning of multiple sensory events to delayed rewards, as during serial compound conditioning.
陈述性记忆和程序性记忆的概念被用来区分两种基本的学习类型。一个神经网络模型表明，在自适应行为中发生识别学习、强化学习和感觉运动学习时，这些记忆过程是如何协同工作的。为了协调这些过程，海马体和小脑都包含了学习自适应地调整其输出时间的回路。在该模型中，海马体的计时有助于在可变的任务相关延迟期间，将注意力保持在动机显著的目标物体上，而小脑的计时则控制条件反应的释放。这个特性是模型描述认知-情绪相互作用如何将注意力集中在有动机价值的线索上的一部分，以及这个过程如何由于海马体消融而崩溃。该模型表明，帮助快速将注意力吸引到显著线索的海马体机制可能会过早地释放运动命令，如果这些命令不是由小脑自适应地计时释放的话。模型的海马体系统调节皮质识别学习，而实际上并不编码皮质编码的表示信息。这些特性避免了几个提出海马体在识别学习中直接作用的模型所面临的困难。模型海马体系统中的学习控制自适应计时和空间定向。模型的特性阐明了海马体消融如何导致健忘症状以及在任务中遇到困难，这些任务结合了任务延迟、新颖性检测以及在分心时对目标物体的注意力。当这些模型的识别、强化、感觉运动和计时过程协同工作时，它们表明了大脑如何能够完成对多个延迟奖励的感官事件的条件作用，就像在序列复合条件作用中一样。
