Fine-scale direction tuning of vertical system (VS)1 cell dendrites. (a) VS1 cell stained with Oregon Green BAPTA-1 showing the positions of the recording areas B-D. (b) Calcium response field of the dorsomedial dendrite to a square grating moving in eight directions. Presentation as in Figure 3. (c) Response field of the dorsal and (d) of the lateral dendritic branch of the same VS cell. Images b-d were taken at 10 Hz and 256 × 256 pixel resolution with multifocal two-photon laser-scanning microscopy.