Optical imaging with voltage-sensitive dyes (VSD imaging) can record neural activity over an area of several square centimeters with high spatiotemporal resolution. The relative contributions of subthreshold and suprathreshold activity to the VSD signal are, however, poorly understood, making it difficult to interpret the imaging result. This paper shows how the activity in a computational model of V1 can be related to the VSD signal. The orientation tuning curve and the response time course in the model match those observed in VSD imaging, suggesting that the model represents VSD signal accurately and can be used to link neural activity to it. Key words: Optical Imaging, Voltage-Sensitive Dyes, Computational Model