The rodent whisker sensory system is a commonly used model of cortical processing, however, anesthetics cause profound differences in the shape and timing of evoked responses. Evoked response studies, especially those using spatial mapping techniques, such as fMRI or optical imaging will thus show significantly different results depending on the anesthesia used. To describe the effect of behavioral states and commonly used anesthetics, we characterized the early surface evoked response potentials (ERP) components (First ERP peak, GAMMA band 25-45 Hz, fast oscillation FO 200-400 Hz, and very fast oscillation VFO 400-600 Hz) using a 25 channel electrode array on the somatosensory cortex during whisker stimulation. We found significant differences in the ERP shape under ketamine/xylazine, urethane, propofol, isoflurane, pentobarbital, and during sleep/wake states. The highest ERP amplitudes were observed under propofol anesthesia and during quiet sleep. Under isoflurane, the ERP was nearly absent, except for a very late component which was concombinant with burst synchronization. The slowest responses were seen under urethane and propofol anesthesia. Spatial mapping experiments that use electrical, NMR, or optical techniques must consider the anesthetic dependency of these signals, especially when comparing stimulation protocols or electrical and metabolic responses.