Circadian Rhythms
RDoC Classification
Domain: Arousal and Regulatory Systems
Description
Circadian Rhythms are endogenous self-sustaining oscillations that organize the timing of biological systems to optimize physiology and behavior, and health. Circadian Rhythms:
- Are synchronized by recurring environmental cues;
- Anticipate the external environment;
- Allow effective response to challenges and opportunities in the physical and social environment;
- Modulate homeostasis within the brain and other (central/peripheral) systems, tissues and organs;
- Are evident across levels of organization including molecules, cells, circuits, systems, organisms, and social systems.
Molecules
Input
DopamineGABAGlutamateMelanopsinNPYPACAPSubstance PSCN Synchronizing and Modulating Agents
AVPCalbindincAMPcGMPNOSteroid hormonesVIPOutput
AVPCortisolGABAMelatoninVIPCells
Circuits
Input
Raphe to SCN projectionRetinal cellsRetino-hypothalamic tractRetinogeniculate tractOutput
Basolateral amygdala/ HippocampusCentral extended amygdala (central nucleus of the amygdala / Bed nucleus of the stria terminalis)HPA axisHypothalamic neuroendocrine cell groupsHypothalamic orexin projectionsPVN, DMH, subparaventricular zone, PVTSCN/PVN/SCG/pinealSympathetic / parasympathetic nervous systemIntrinsic to SCN
Suprachiasmatic nucleus (SCN) core/shellSeasonal
SCN/PVN/SCG/pinealPhysiology
Behavior
Self-Report
Paradigms
Genetic Approaches – genome-wide association study, candidate gene, epigenomics, circadian genomics (temporal gene expression), mutagenesis, gene targeting, quantitative trait loci.