  Barn owls hunt in the dark by using cues from both sight and sound to locate
their prey. This task is facilitated by topographic maps of the external space
formed by neurons (e.g., in the optic tectum) that respond to visual or aural
signals from a specific direction. Plasticity of these maps has been studied in
owls forced to wear prismatic spectacles that shift their visual field.
Adaptive behavior in young owls is accompanied by a compensating shift in the
response of (mapped) neurons to auditory signals. We model the receptive fields
of such neurons by linear filters that sample correlated audio-visual signals,
and search for filters that maximize the gathered information, while subject to
the costs of rewiring neurons. Assuming a higher fidelity of visual
information, we find that the corresponding receptive fields are robust and
unchanged by artificial shifts. The shape of the aural receptive field,
however, is controlled by correlations between sight and sound. In response to
prismatic glasses, the aural receptive fields shift in the compensating
direction, although their shape is modified due to the costs of rewiring.
