Bilateral long-range interaction between right and left visual hemifield

Long-range interaction has been reported to be limited in space within a few degrees. Here, we present a new type of interaction by means of a bilateral configuration using two Gabor signals (GSs). Two horizontally oriented GSs, the first defined as a cue and the second as a probe, appeared in the right and left peripheral visual fields in mirror symmetrical regions. The detection threshold of the GS probe was found to decrease significantly up to cue-probe separations of 10 degrees tested. Since the interaction was sensitive to symmetrical locus, as well as specific to the direction of the horizontal axis, the results suggest novel long-range interaction extending toward the periphery with a mirror-symmetrical configuration. This may be acquired by neuronal communication, which directly connects bilateral receptive fields in the right and left visual cortices.