while the scratch reflex can be produced without supraspinal structures, research indicates that neurons in the motor cortex play a role in the modulation of the scratch reflex as well. stimulation of pyramidal tract neurons has been found to modulate the timing and intensity of scratch reflex. furthermore, extensive research has identified the involvement of supraspinal structures in the modulation of the rhythmic elements of the scratch reflex. the current theory is that efference copies from cpgs travel to the cerebellum via spinocerebellar pathways. these signals then modulate the activity of the cerebellar cortex and nuclei, which in turn regulate descending tract neurons in the vestibulospinal, reticulospinal, and rubrospinal tracts. presently, there is not much else known about the specifics of supraspinal control of the scratch reflex.