Lesions of the dorsal noradrenergic bundle simultaneously enhance and reduce responsivity to novelty in a food preference test.

In conclusion, DNAB lesions have been shown to have two, apparently contradictory effects in a food preference test: to increase neophobia to a novel environment, and to increase the tendency to eat novel food in a novel environment. It has been suggested that these two effects occur because, although NA has a common action on neuronal firing in terminal fields, the dissociable consequences reflect the different functions of areas in receipt of these noradrenergic afferents. In addition, it has been shown that DNAB lesions, VNAB lesions, and a benzodiazepine, chlordiazepoxide, all have somewhat different behavioral effects in the food preference test. Taken together with the lack of correlation between the various behavioral measures used in these experiments, this suggests that neophobia does not reflect a single behavioral process, such as anxiety, or reactivity to novelty.