Ferreiro Dardo N, Amaro Diana, Schmidtke Daniel, Sobolev Andrey, Gundi Paula, Belliveau Lucile, Sirota Anton, Grothe Benedikt, Pecka Michael
Division of Neurobiology, Department Biology II, Ludwig-Maximilians-Universität München, Munich, Germany.
Department of General Psychology and Education, Ludwig-Maximilians-Universität München, Munich, Germany.
Front Behav Neurosci. 2020 Sep 25;14:576154. doi: 10.3389/fnbeh.2020.576154. eCollection 2020.
A central function of sensory systems is the gathering of information about dynamic interactions with the environment during self-motion. To determine whether modulation of a sensory cue was externally caused or a result of self-motion is fundamental to perceptual invariance and requires the continuous update of sensory processing about recent movements. This process is highly context-dependent and crucial for perceptual performances such as decision-making and sensory object formation. Yet despite its fundamental ecological role, voluntary self-motion is rarely incorporated in perceptual or neurophysiological investigations of sensory processing in animals. Here, we present the Sensory Island Task (SIT), a new freely moving search paradigm to study sensory processing and perception. In SIT, animals explore an open-field arena to find a sensory target relying solely on changes in the presented stimulus, which is controlled by closed-loop position tracking in real-time. Within a few sessions, animals are trained via positive reinforcement to search for a particular area in the arena ("target island"), which triggers the presentation of the target stimulus. The location of the target island is randomized across trials, making the modulated stimulus feature the only informative cue for task completion. Animals report detection of the target stimulus by remaining within the island for a defined time ("sit-time"). Multiple "non-target" islands can be incorporated to test psychometric discrimination and identification performance. We exemplify the suitability of SIT for rodents (Mongolian gerbil, ) and small primates (mouse lemur, ) and for studying various sensory perceptual performances (auditory frequency discrimination, sound source localization, visual orientation discrimination). Furthermore, we show that pairing SIT with chronic electrophysiological recordings allows revealing neuronal signatures of sensory processing under ecologically relevant conditions during goal-oriented behavior. In conclusion, SIT represents a flexible and easily implementable behavioral paradigm for mammals that combines self-motion and natural exploratory behavior to study sensory sensitivity and decision-making and their underlying neuronal processing.
感觉系统的一个核心功能是在自我运动过程中收集有关与环境动态交互的信息。确定感觉线索的调制是外部引起的还是自我运动的结果，这对于感知不变性至关重要，并且需要不断更新关于近期运动的感觉处理。这个过程高度依赖于上下文，对于诸如决策和感觉对象形成等感知表现至关重要。然而，尽管其具有基本的生态作用，但在动物感觉处理的感知或神经生理学研究中，自愿自我运动很少被纳入。在这里，我们提出了感觉岛任务（SIT），这是一种新的自由移动搜索范式，用于研究感觉处理和感知。在SIT中，动物探索一个开放场竞技场，仅依靠所呈现刺激的变化来寻找感觉目标，该刺激由实时闭环位置跟踪控制。在几个训练阶段内，通过正强化训练动物在竞技场中搜索特定区域（“目标岛”），这会触发目标刺激的呈现。目标岛的位置在试验中是随机的，使得调制后的刺激特征成为任务完成的唯一信息线索。动物通过在岛内停留一段规定时间（“停留时间”）来报告检测到目标刺激。可以纳入多个“非目标”岛来测试心理测量辨别和识别性能。我们举例说明了SIT适用于啮齿动物（蒙古沙鼠）和小型灵长类动物（小鼠狐猴），以及用于研究各种感觉感知表现（听觉频率辨别、声源定位、视觉方向辨别）。此外，我们表明将SIT与慢性电生理记录相结合，可以揭示在目标导向行为期间生态相关条件下感觉处理的神经元特征。总之，SIT代表了一种灵活且易于实施的哺乳动物行为范式，它结合了自我运动和自然探索行为来研究感觉敏感性和决策及其潜在的神经元处理。
