FIG. 8.

Schematic of 3 inhibitory surrounds. A: increased single-site stimulation produces increased amplitude without change in area of activation. In addition, local surround falls below baseline (cf. Simons et al. 2005, 2007). B: addition of a second stimulus at an adjacent digit leads to decreased amplitude (vertical arrow) and area (horizontal arrows) of response. C: addition of a second stimulus at a nonadjacent digit leads to decreased area (horizontal arrows) but little change in response amplitude. Adjacent digit stimulation produces a stronger suppressive effect than nonadjacent digit stimulation (compare horizontal arrows in B and C).