Fig 4. The model function of visuo-auditory multisensory integration.

This is the equation of the model for audition-dependent modulation. R is response firing rate; ϕ_V, ϕ_A are azimuths of visual and auditory stimuli, respectively; I_V, I_A are intensity of the visual or auditory stimuli, respectively; α is a modulation weight for a neuron; δ is a global modulation function for a mouse; S is a sigmoidal function; and b is a baseline firing rate. See Materials and methods for details. For the vision-dependent model, the global modulation function δ depends on ϕ_V and I_V. For the no-modulation model, α is fixed to 1.