Investigating the brain circuitry underlying crossmodal object recognition

人类的意识体验来自于对来自多个感官来源的刺激的感知。神经科学领域的一个重要问题涉及到将多感觉信息整合为有意义表征的大脑机制。本研究将利用啮齿动物模型研究多感觉信息处理的神经机制。具体来说，我们将研究跨模态物体识别的神经基础，即动物在不同感官模态下识别先前探索过的物体的能力。我们已经证明，老鼠可以通过视觉识别一个物体，而这个物体以前只能通过触摸来探索。我们提出的研究将评估参与这种适应性认知形式的互动脑回路。第二种类型的行为任务将使用配备触摸屏的计算机室来测量大脑操作对直接多感觉整合的影响。例如，对人类的研究表明，同时呈现与行为相关的听觉和视觉刺激会大大加快反应时间。我们将使用触屏室来开发这种多感觉整合任务的鼠标版本。这些实验室将使我们能够更有效、更灵活地进行实验，并将促进与人类发现的跨物种比较。随着这些任务的建立，我们将开始测试转基因小鼠，以评估选择性删除各种神经递质受体对多感觉整合的影响。像这样的动物研究对于我们观察神经操作和行为变化之间的因果关系至关重要。因此，我们的研究计划应该有助于阐明多感觉整合的大脑机制，多感觉整合是一种认知能力，其适应性优势影响许多重要的心理功能，包括感知、记忆、语言、情感和意识。因此，这项研究项目将产生有助于我们理解哺乳动物大脑基本功能的知识，并可能为优化人类认知功能的努力提供信息。

Human conscious experience arises from the perception of stimuli originating from multiple sensory sources. An important question in the field of neuroscience relates to the brain mechanisms involved in the integration of multisensory information into meaningful representations. The proposed research will use rodent models to study the neural mechanisms of multisensory information processing. Specifically, we will study the neural bases of crossmodal object recognition, the ability of an animal to recognize a previously-explored object when it is presented in a different sensory modality. We have shown that rats can recognize an object visually when it has only previously been explored by touch. Our proposed research will assess the interactive brain circuitry involved in this adaptive form of cognition. A second type of behavioural task will use computerized touchscreen-equipped chambers to measure the effects of brain manipulations on direct multisensory integration. For example, human studies indicate that reaction times are significantly facilitated by the simultaneous presentation of behaviourally relevant auditory and visual stimuli. We will use touchscreen chambers to develop mouse versions of this kind of multisensory integration task. These chambers will enable us to run experiments more efficiently and flexibly and will facilitate cross-species comparisons with human findings. With these tasks established, we will begin to test genetically modified mice to assess the impact on multisensory integration of selective deletion of various neurotransmitter receptors. Animal studies like these are essential in enabling us to observe cause and effect relationships between neural manipulations and behavioural changes. As such, our research program should help to shed light on the brain mechanism underlying multisensory integration, a cognitive ability whose adaptive advantage impacts numerous vital psychological functions, including perception, memory, language, emotion, and consciousness. This research program will therefore generate knowledge that will contribute to our understanding of the basic functions of the mammalian brain and which may inform efforts to optimize human cognitive function.