AANAT	Arylalkylamine N-Acetyltransferase
AD	Alzheimer’s Disease
AKT	Protein Kinase B
ALAN	Artificial Light at Night
ALS	Amyotrophic Lateral Sclerosis
AMPK	AMP-Activated Protein Kinase
AQP-4	Aquaporin-4
ASMT	Acetylserotonin O-Methyltransferase
AVP	Arginine Vasopressin
Aβ	Amyloid-Beta
BBB	Blood–Brain Barrier
BDNF	Brain-Derived Neurotrophic Factor
BMAL1	Brain and Muscle ARNT-Like 1
CCG	Clock-Controlled Genes
CK1δ/ε	Casein Kinase 1 Delta/Epsilon
CLOCK	Circadian Locomotor Output Cycles Kaput
CREB	cAMP Response Element-Binding Protein
CRY	Cryptochrome (gene family)
CSF	Cerebrospinal Fluid
DLB	Dementia with Lewy Bodies
DLMO	Dim-Light Melatonin Onset
GSK3β	Glycogen Synthase Kinase-3 Beta
HD	Huntington’s Disease
HIOMT	Hydroxyindole-O-Methyltransferase
HPA	Hypothalamic–Pituitary–Adrenal (axis)
ipRGC	Intrinsically Photosensitive Retinal Ganglion Cells
MDD	Major Depressive Disorder
MMP	Matrix Metalloproteinase
MMSE	Mini-Mental State Examination
MoCA	Montreal Cognitive Assessment
MPTP	1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine
MS	Multiple Sclerosis
MT	Music Therapy
MT1	Melatonin Receptor 1A
MT2	Melatonin Receptor 1B
NLRP3	NOD-like Receptor Protein 3
PD	Parkinson’s Disease
PER	Period (gene family)
PGC-1α	Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-Alpha
PI3K	Phosphatidylinositol 3-Kinase
RBD	REM Sleep Behavior Disorder
REV-ERBα	Reverse-Erb Alpha
RORα	Retinoic Acid Receptor-Related Orphan Receptor Alpha
ROS	Reactive Oxygen Species
RRE	ROR Response Element
SCFA	Short-Chain Fatty Acids
SCN	Suprachiasmatic Nucleus
SIRT1	Sirtuin 1
TRE	Time-Restricted Eating
TTFL	Transcriptional–Translational Feedback Loop
VIP	Vasoactive Intestinal Peptide