Fiber pathways associated with cerebellar self-stimulation in the rat: a retrograde and anterograde tracing study

Intracranial self-stimulation (ICSS) was obtained from an area of cerebellum just rostro-ventral to the fastigial nucleus. The acquisition of cerebellar ICSS was slow, although this depended in part on the type of operant task required. The afferent and efferent fiber connections of the region of cerebellum supporting ICSS were identified using silver-degeneration and horseradish peroxidase tracing techniques. Two major pathways, one ascending to the ventromedial thalamus and one descending to the paramedian reticular formation and the region of the solitary nucleus, are discussed as possible substrates of ICSS at sites in the cerebellum as well as from other pontine and medullary regions.