a, The cartoon illustrates the imaging planes of the optical horizontal sections at different depths of the amygdala. The brain diagrams were rendered by the scalable brain composer (https://scalablebrainatlas.incf.org/services/sba-composer.php?template=ABA_v3) based on the Allen Mouse Brain Common Coordinate Framework version 326,27. b, Segregation of sweet and bitter cortical projections in the amygdala. Sweet cortical neurons project to anterior BLA (green), whereas bitter cortical neurons predominantly innervate the CEA (red) and a portion of the posterior BLA (red). Top, optical horizontal sections at different dorsal–ventral positions are shown (sections 1–4; see a). Bottom, the boundaries of amygdala nuclei were determined by aligning fluorescence images to the Allen Brain Institute atlas26 (http://brain-map.org/). Scale bar, 500 μm. Similar results were observed in six independently labelled and imaged animals.