Beyond correlations: causally linking neural circuits and consciousness in rodents

Research into the neural mechanisms of consciousness has so far mainly progressed through human neuroscience. However, most of the available techniques for use in human subjects lack the ability to probe the underlying neuron- and circuit-level mechanisms. Animal experiments offer a promising solution to these limitations. In particular, experiments in rodents allow us to combine large-scale neuronal recordings with the causal manipulations of neuronal activity. Although non-human species cannot verbally report their subjective experiences, behavioral indicators of consciousness have proven to be reliable across species, and the range of behavioral tests available for rodents has grown substantially. This chapter reviews recent advances in using rodents for consciousness research, emphasizing how microcircuit-level studies have the potential to majorly expand theoretical frameworks. We will highlight two key aspects that make rodents particularly valuable for consciousness science: novel behavioral assays and perturbational methods such as optogenetics. Ultimately, we aim to provide evidence that experiments in rodents need to become part of the standard toolbox for consciousness science, complementing and expanding insights gained from human experiments.