title: Mutual entrainment of bilaterally distributed circadian pacemaker.
abstract: The interactions between the bilaterally distributed components of the circadin system that controls the locomotor activity rhythm of the cockroach Leucophaea maderae were investigated in a series of surgical lesion experiments. Complete excision of one optic lobe (either right or left) or its surgical isolation from the central nervous system had no effect on the animals' ability to free-run in constant darkness nor was there any indication, as judged by postoperative pi values of any difference between left and right lobe pacemakers. However, these surgical procedures consistently resulted in a significant increase in tau over preoperative value while optic nerve section had no effect on tau. The propostion is developed that the left and right pacemakers in the two optic lobes are mutally coupled and that the compound pacemaker's period is shorter than either of its constituent pacemakers. It was also found that the integrity of either compound eye is sufficient to assure entrainment of both left and right pacemakers.
mesh_terms: D000818:Animals; D001683:Biological Clocks; D002940:Circadian Rhythm; D003058:Cockroaches / Q000502:physiology*; D007839:Functional Laterality; D008027:Light; D009043:Motor Activity / Q000502:physiology; D009799:Ocular Physiological Phenomena; D009899:Optic Lobe, Nonmammalian / Q000502:physiology
references.citation: Science. 1976 Jan 16;191(4223):197-9
references.pmid: 942799
references.citation: Brain Res. 1975 Apr 4;87(1):13-21
references.pmid: 1120252
references.citation: Photophysiology. 1976 Apr;23(4):253-73
references.pmid: 1273097
references.citation: Proc Natl Acad Sci U S A. 1972 Jun;69(6):1583-6
references.pmid: 4556464
references.citation: Brain Res. 1972 Jul 13;42(1):201-6
references.pmid: 5047187
references.citation: Science. 1971 Mar 19;171(3976):1167-9
references.pmid: 5544875
references.citation: Science. 1969 May 2;164(3879):562-3
references.pmid: 5778006
references.citation: Cold Spring Harb Symp Quant Biol. 1960;25:159-84
references.pmid: 13736116
references.citation: Proc Natl Acad Sci U S A. 1956 Sep;42(9):676-82
references.pmid: 16589930
references.citation: Science. 1970 Mar 20;167(3925):1624-6
references.pmid: 17746371
references.citation: Science. 1965 May 14;148(3672):958-9
references.pmid: 17751048