Viewpoint on Single-Neuron Multisensory Dynamics

Abstract

In this viewpoint article, Florencia Iacaruso, Benjamin A. Rowland and Barry E. Stein examine the principles and open questions surrounding single-neuron dynamics in multisensory integration. Drawing on decades of work, they emphasize that individual neurons, particularly in structures such as the superior colliculus, exhibit rapid, nonlinear interactions when combining inputs from different sensory modalities. These dynamics are shaped by experience, circuit architecture, and the precise timing and balance of converging inputs, rather than reflecting fixed or purely feedforward processes. The authors highlight that single-neuron responses provide a critical bridge between cellular mechanisms and behaviour, revealing how multisensory signals are integrated in real time to support detection, localization, and decision-making. Recent methodological advances, including high-density electrophysiology, calcium imaging, and computational modelling, are enabling more detailed characterization of these dynamics within distributed and context-dependent networks. Key open questions focus on the origin of multisensory effects observed at the single-neuron level, including whether they arise from local circuit computations or reflect inputs inherited from broader network interactions. The variability of neuronal responses across contexts, such as changes in attention, behavioural state, and task demands, further complicates the identification of general principles. Looking forward, the authors argue that integrating large-scale functional data with anatomical connectivity and artificial intelligence approaches will be essential for linking single-neuron dynamics to system-level function. They conclude that understanding multisensory processing at the level of individual neurons remains central to explaining how the brain constructs coherent perception from diverse sensory inputs.