1. A touch detection circuit comprising: a map generation section configured to compare a touch signal corresponding to a proximity state of an external proximity object with each of a plurality of thresholds to generate a plurality of pieces of map data each showing touch regions; a labeling section configured to selectively perform labeling on the touch regions in the plurality of pieces of map data, based on inclusive relationship of the touch regions between the plurality of pieces of map data; and a detection section configured to perform touch detection based on processing results by the labeling section.