Dreams are internally generated experiences that occur independently of current sensory input. Here we argue, based on cortical anatomy and function, that dream experiences are tightly related to the workings of a specific part of cortical pyramidal neurons, the apical integration zone (AIZ). The AIZ receives and processes contextual information from diverse sources and could constitute a major switch point for transitioning from externally to internally generated experiences such as dreams. We propose that during dreams the output of certain pyramidal neurons is mainly driven by input into the AIZ. We call this mode of functioning “apical drive”. Our hypothesis is based on the evidence that the cholinergic and adrenergic arousal systems, which show different dynamics between waking, slow wave sleep, and rapid eye movement sleep, have specific effects on the AIZ. We suggest that apical drive may also contribute to waking experiences, such as mental imagery. Future studies, investigating the different modes of apical function and their regulation during sleep and wakefulness are likely to be richly rewarded.

梦想是内部产生的体验，独立于当前的感官输入而发生。在这里，我们认为，基于皮质解剖结构和功能，梦的经历与皮质锥体神经元的特定部分，根尖整合区（AIZ）的工作紧密相关。AIZ接收并处理来自各种来源的上下文信息，并且可能构成从外部体验到内部体验（例如梦）过渡的主要切入点。我们提出在梦中某些锥体神经元的输出主要是由输入AIZ驱动的。我们称这种功能为“顶驱”。我们的假设基于以下证据：胆碱能和肾上腺素能唤醒系统在清醒，慢波睡眠和快速眼动睡眠之间表现出不同的动态，对AIZ有特定影响。我们建议，根尖驱动也可能有助于唤醒体验，例如心理意象。未来的研究可能会获得丰厚的回报，这些研究调查了不同的心尖功能模式及其在睡眠和清醒过程中的调节。