Title : Adaptive Shaping of Cortical Response Selectivity in the Vibrissa Pathway

Author Contributions HJVZ, QW and GBS conceived and designed the experiments. HJVZ conducted the experiments and analyzed the corresponding data. HJVZ and GBS wrote the paper. Abstract 1 One embodiment of context-dependent sensory processing is bottom-up adaptation, where 2 persistent stimuli decrease neuronal firing rate over hundreds of milliseconds. Adaptation is not, 3 however, simply the fatigue of the sensory pathway, but shape the information flow and 4 selectivity to stimulus features. Adaptation enhances spatial discriminability (distinguishing 5 stimulus location) while degrading detectability (reporting presence of the stimulus), for both 6 the ideal observer of the cortex and awake, behaving animals. However, how the dynamics of 7 the adaptation shape the cortical response and this detection and discrimination tradeoff is 8 unknown, as is to what degree this phenomenon occurs on a continuum as opposed to a 9 switching of processing modes. Using voltage-sensitive dye imaging in anesthetized rats to 10 capture the temporal and spatial characteristics of the cortical response to tactile inputs, we 11 showed that the suppression of the cortical response, in both magnitude and spatial spread, is 12 continuously modulated by the increasing amount of energy in the adapting stimulus, which is 13 non-uniquely determined by its frequency and velocity. Single-trial ideal observer analysis 14 demonstrated a tradeoff between detectability and spatial discriminability up to a moderate 15 amount of adaptation, which corresponds to the frequency range in natural whisking. This was 16 accompanied by a decrease in both detectability and discriminability with high-energy 17 adaptation, which indicates a more complex coupling between detection and discrimination 18 than a simple switching of modes. Taken together, the results suggest that adaptation operates 19 on a continuum and modulates the tradeoff between detectability and discriminability that has 20 implications for information processing in ethological contexts.