Previous attempts to identify a unified theory of brain serotonin function have largely failed to
achieve consensus. In this present synthesis, we integrate previous perspectives with new …

The serotonergic system forms a diffuse network within the central nervous system and plays
a significant role in the regulation of mood and cognition. Manipulation of tryptophan levels …

Gastrointestinal and central function are intrinsically connected by the gut microbiota, an
ecosystem that has co-evolved with the host to expand its biotransformational capabilities …

The “serotonin hypothesis” of clinical depression is almost 50 years old. At its simplest, the
hypothesis proposes that diminished activity of serotonin pathways plays a causal role in the …

Depression is a global threat to mental health that affects around 264 million people
worldwide. Despite the considerable evolution in our understanding of the pathophysiology …

The monoamine hypothesis of depression predicts that the underlying pathophysiologic
basis of depression is a depletion in the levels of serotonin, norepinephrine, and/or …

Dysfunction in the monoamine systems of serotonin (5-HT), norepinephrine (NE) and
dopamine (DA) may causally be related to major depressive disorder (MDD). Monoamine …

Suicide ranks among the leading causes of death around the world and takes a heavy
emotional and public health toll on most societies. Both distal and proximal factors contribute …

Epidemiological and clinical data indicate high comorbidity between depression and drug
dependence that may reflect an attempt to self-medicate with drugs of abuse. The present …

Abstract Serotonin, like dopamine (DA), has long been implicated in adaptive behavior,
including decision making and reinforcement learning. However, although the two …