We propose to examine the possible behavioral significance of a recently discovered neural growth which occurs in the rat brain as a result of lesions of the anterior hippocampal formation, fornix-fimbria or septal nucleus. This unusual growth, termed anomalous sympathetic innervation (ASI) is the result of collateral sprouting of axons whose cell bodies are located in the superior cervical ganglia of the sympathetic nervous system. This anomalous innervation, first discovered by Loy and Moore in 1977, has now been observed in several other laboratories as well. Although subsequent electron microscopy by Loy has indicated that these sprouting collaterals are in all likelihood forming synaptic contacts, the functional significance of ASI is unknown. The development of ASI can be completely prevented by removal of the superior cervical ganglia. We propose to examine the behavior of rats with discrete lesions of the anterior hippocampus and extensive ASI, in comparison with that of rats with similar hippocampal lesions but no ASI. The ASI in the latter group will be prevented by bilateral superior cervical ganglia removal. Some of the behaviors to be examined include spontaneous alternation, spatial maze acquisition and conditioned taste aversion.