OCD	Obsessive–compulsive disorder
OCS	Obsessive–compulsive symptoms
GM	Gut microbiome
GBA	Gut–brain axis
GAD	Generalized anxiety disorder
MDD	Major depressive disorder
ADHD	Attention-deficit/hyperactivity disorder
ELS	Early-life stress
CSTC	Cortico-striato-thalamo-cortical
GWAS	Genome-wide association studies
MAF	Minor allele frequency
CNV	Copy number variant
WES	Whole exome sequencing
DNAm	DNA methylation
miRNA	microRNA
EWAS	Epigenome-wide association studies
fMRI	Functional magnetic resonance imaging
SRIs	Serotonin reuptake inhibitors
SSRIs	Selective serotonin reuptake inhibitors
PANDAS	Pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection
PANS	Pediatric acute-onset neuropsychiatric syndrome
TAF	Thought–action fusion
NP	Negative priming
IBA	Inverse Bayesian account
SLEs	Stressful life events
ACEs	Adverse childhood experiences
SCFA	Short-chain fatty acid
CNS	Central nervous system
MR	Mendelian randomization
BBB	Blood–brain barrier
ASD	Autism spectrum disorder
GABA	γ-aminobutyric acid
CBT	Cognitive–behavioral therapy
GOS	Galactooligosaccharides
FOS	Fructooligosaccharides
NJREs	Not just right experiences
FMT	Fecal microbiota transplantation