Elliott Blake L, O'Brien Kathleen J, Fain Matthew, Ellman Lauren M, Murty Vishnu P
bioRxiv. 2025 Aug 22:2024.12.16.628816. doi: 10.1101/2024.12.16.628816.
The ability to adapt to a dynamic world relies on detecting, learning, and responding to environmental changes. The detection of novelty serves as a critical indicator of such changes, priming mechanisms to detect and respond to goal-relevant information. However, neural regions that support novelty detection (hippocampus) and goal-directed behavior (dopaminergic midbrain [VTA] and prefrontal cortex [PFC]) have yet to be described as a sequential process that unfolds over time. Using a forward-prediction functional magnetic resonance imaging (fMRI) model, we explored interactions between the hippocampus, VTA, and PFC in humans performing a novelty-imbued target-detection task. Hippocampal novelty activation predicted subsequent VTA target activation, enhancing readiness to detect goal-relevant information. Concurrently, goal-directed PFC activation modulated VTA target activation, refining focus on behaviorally significant cues. These circuits function both synergistically and independently, promoting subsequent hippocampal activity during target trials. This work provides new insights into how distributed circuits coordinate to optimize adaptive behavior.
Surviving in dynamic environments requires coordinated neural mechanisms to detect, learn from, and respond to change. However, neural regions that support novelty detection and goal-oriented behavior have yet to be described as a sequential process that unfolds over time. Using a novel forward-prediction functional magnetic resonance imaging (fMRI) model, we show that hippocampal activation during novelty predicts VTA readiness to process goal-relevant information. Concurrently, goal-directed PFC activity modulates VTA responses, sharpening focus on behaviorally significant cues. Furthermore, these synergistic and independent circuits enhance hippocampal sensitivity for future adaptive responses, offering novel insights into integration of brain mechanisms critical for learning, motivation, and executive function. Biological Sciences, Neuroscience.
适应动态世界的能力依赖于对环境变化的检测、学习和响应。新奇性的检测是此类变化的关键指标，启动检测和响应与目标相关信息的机制。然而，支持新奇性检测的神经区域（海马体）和目标导向行为的神经区域（多巴胺能中脑[腹侧被盖区]和前额叶皮质[PFC]）尚未被描述为一个随时间展开的连续过程。使用前瞻性预测功能磁共振成像（fMRI）模型，我们探索了人类在执行充满新奇性的目标检测任务时海马体、腹侧被盖区和前额叶皮质之间的相互作用。海马体的新奇性激活预测了随后腹侧被盖区的目标激活，增强了检测与目标相关信息的准备状态。同时，目标导向的前额叶皮质激活调节了腹侧被盖区的目标激活，使注意力更集中于行为上重要的线索。这些神经回路协同且独立地发挥作用，在目标试验期间促进随后的海马体活动。这项工作为分布式神经回路如何协同以优化适应性行为提供了新的见解。
在动态环境中生存需要协调的神经机制来检测、从中学习并对变化做出反应。然而，支持新奇性检测和目标导向行为的神经区域尚未被描述为一个随时间展开的连续过程。使用一种新颖的前瞻性预测功能磁共振成像（fMRI）模型，我们表明新奇性期间的海马体激活预测了腹侧被盖区处理与目标相关信息的准备状态。同时，目标导向的前额叶皮质活动调节腹侧被盖区的反应，使注意力更集中于行为上重要的线索。此外，这些协同且独立的神经回路增强了海马体对未来适应性反应的敏感性，为对学习、动机和执行功能至关重要的脑机制整合提供了新的见解。生物学、神经科学。
