The present study evaluated the use of computer-assisted image analysis for investigating the temporal alterations in microtubule-associated protein 2 (MAP-2) immunoreactivity in the piriform cortex following acute soman intoxication. Brain samples harvested at various time points after the onset of soman-induced seizures were immunostained with MAP-2 antibody. Color digital images captured with a color digital camera were converted to grayscale images and enhanced to identify the areas of MAP-2 immunoreactivity from the background. Segmentation was then performed by thresholding to highlight pixels occupied by the MAP-2 immunostain. The average total area of MAP- 2 immunostaining in the piriform cortex was significantly decreased by 20% (P0.001) 1 hr after soman-induced seizure onset as compared to control counterparts. Differences in the mean total area of MAP-2 immunostaining at 3 and 6 hr after seizure onset were not significantly different from the average total value obtained from 1 hr. At 12 hr, loss of MAP-2 immunostaining was visually obvious in layers II and III, and the total area occupied by MAP-2 immunostaining was significantly reduced by 65%. At 24 hr, only 17% of the total area was occupied by MAP-2 immunostaining. Using this technique, alterations in MAP-2 immunoreactivity were consistently quantified and reproducible.