Fuster Joaquín M
Semel Institute for Neuroscience and Human Behavior, School of Medicine, University of California Los Angeles, Los Angeles, CA, United States.
Handb Clin Neurol. 2019;163:3-15. doi: 10.1016/B978-0-12-804281-6.00001-X.
Throughout the nervous system, posterior structures are mainly devoted to receptive functions-sensation and perception-while anterior structures are devoted to motor functions. In the cortex, that dichotomy is unclear because perception and action are intertwined in the perception-action cycle, the biocybernetic cycle that adapts the organism to its environment. All neural systems store information (memory), which they enact in behavior and language. There are no "systems of memory" but the memory of systems. The cortex of the frontal lobe is a hierarchical system: motor cortex at the bottom for coordination of simple movements, and prefrontal cortex at the top for complex goal-directed actions. In the coordination of such actions, the frontal hierarchy engages the posterior (perceptual) cortex in the perception-action cycle. Inputs to the cycle come to prefrontal cortex from sensory-evoked perceptual memory and biologic (phyletic) memory. The first comes from neocortex, the second from limbic structures-through orbitomedial cortex. Outputs flow to pyramidal and diencephalic structures. Feedback inputs for monitoring and correction operate at all levels of the cycle. All prefrontal functions-planning, executive attention, working memory, decision-making, and inhibitory controls-are prospective, i.e., have a future perspective for the cycle to reach its goal. Damage to lateral prefrontal cortex impairs all of them. Orbitofrontal damage impairs the exclusionary aspect of attention and often leads to poor impulse control, excessive risk taking, unstable mood, and antisocial behavior. Medial prefrontal damage leads to poor monitoring of behavioral outcome for prevention of errors.
在整个神经系统中，后部结构主要负责接受功能——感觉和感知，而前部结构则负责运动功能。在皮质中，这种二分法并不明确，因为感知和行动在感知 - 行动循环中相互交织，这是一种使生物体适应其环境的生物控制论循环。所有神经系统都存储信息（记忆），并在行为和语言中表现出来。不存在“记忆系统”，只有系统的记忆。额叶皮质是一个分层系统：底部的运动皮质用于协调简单运动，顶部的前额叶皮质用于复杂的目标导向行动。在这种行动的协调中，额叶分层系统在感知 - 行动循环中与后部（感知）皮质相互作用。该循环的输入从前额叶皮质的感觉诱发感知记忆和生物（系统发育）记忆而来。前者来自新皮质，后者通过眶额皮质来自边缘结构。输出流向锥体和间脑结构。用于监测和校正的反馈输入在循环的所有层面上起作用。所有前额叶功能——计划、执行性注意力、工作记忆、决策和抑制控制——都是前瞻性的，即对循环达到其目标具有未来导向性。外侧前额叶皮质受损会损害所有这些功能。眶额损伤会损害注意力的排他性方面，并常常导致冲动控制不佳、过度冒险、情绪不稳定和反社会行为。内侧前额叶损伤会导致对行为结果的监测不佳，从而难以预防错误。
