Language processing involves the ability to store and integrate pieces of information in working memory over short periods of time. According to the dominant view, information is maintained through sustained, elevated neural activity. Other work has argued that short-term synaptic facilitation can serve as a substrate of memory. Here we propose an account where memory is supported by intrinsic plasticity that downregulates neuronal firing rates. Single neuron responses are dependent on experience, and we show through simulations that these adaptive changes in excitability provide memory on timescales ranging from milliseconds to seconds. On this account, spiking activity writes information into coupled dynamic variables that control adaptation and move at slower timescales than the membrane potential. From these variables, information is continuously read back into the active membrane state for processing. This neuronal memory mechanism does not rely on persistent activity, excitatory feedback, or synaptic plasticity for storage. Instead, information is maintained in adaptive conductances that reduce firing rates and can be accessed directly without cued retrieval. Memory span is systematically related to both the time constant of adaptation and baseline levels of neuronal excitability. Interference effects within memory arise when adaptation is long lasting. We demonstrate that this mechanism is sensitive to context and serial order which makes it suitable for temporal integration in sequence processing within the language domain. We also show that it enables the binding of linguistic features over time within dynamic memory registers. This work provides a step toward a computational neurobiology of language.

语言处理涉及在短时间内将信息存储和整合到工作存储器中的能力。根据主流观点，信息是通过持续的，升高的神经活动来保持的。其他工作认为短期的突触促进作用可以作为记忆的基础。在这里，我们提出一个帐户，其中记忆由下调神经元放电速率的内在可塑性支持。单神经元反应取决于经验，我们通过仿真表明，这些兴奋性的自适应变化可在几毫秒到几秒的时间范围内提供记忆。因此，尖峰活动将信息写入耦合的动态变量中，这些变量控制适应性并以比膜电位慢的时间尺度运动。根据这些变量，信息被连续读回到活性膜状态以进行处理。这种神经元记忆机制不依赖于持续活动，兴奋性反馈或突触可塑性来存储。取而代之的是，信息会以自适应电导的形式保存，从而降低发射率，并且无需提示即可直接访问。记忆跨度与适应的时间常数和神经元兴奋性的基线水平系统地相关。当适应时间长时，内存中的干扰效应就会出现。我们证明了这种机制对上下文和序列顺序很敏感，这使其适合于语言域内序列处理中的时间集成。我们还表明，它可以随着时间的推移在动态内存寄存器中绑定语言功能。