Neural connections of sparrow pineal: role in circadian control of activity.

ABSTRACT

Surgical and chemical interference with the neural connections of the house sparrow (Passer domesticus) pineal does not abolish the free-running rhythm in constant darkness, unlike pinealectomy. Pineals transplanted to the anterior chamber of the eye are capable of restoring rhythmicity to pinealectomized birds in constant darkness. The avian pineal does not appear to be neurally coupled to other components of the circadian system.