Figure 3.

Mean number of c-Fos-positive cells (±SEM) in the mediodorsal thalamus in response to novel and familiar chemosensory stimuli. Rats that sampled a novel odor (0.01% isoamyl acetate, light gray bars) had greater expression of c-Fos than those with chemosensory experience (dark gray bars). However, rats with experience with a taste (0.1-M sucrose) or an odor-taste mixture had significantly greater c-Fos expression than rats in the novel taste or the novel odor-taste mixture groups, respectively. *P < 0.05.