Psychiatric disorders are a large class of debilitating mental illnesses that affect everyday life of patients and people around them. In fact, they result in alteration of thinking, moods, behavior and increased risk of disability, pain, death, or loss of freedom. Nevertheless, the exact mechanisms behind these diseases are still unknown. Over the last few years, researchers focused on the study of abnormalities in brain neurodevelopment genetic mutations, impact of traumatic events and the interaction between these factors. In particular, both genetic and environmental factors may influence brain developmental process throughout childhood, adolescence and adulthood. Previous studies investigated how genetic and environmental risk factors act during sensitive brain developmental periods whereby altering adult behavior and possibly causing vulnerability to neuropsychiatric disorders. Different brain systems have been involved in the development of psychiatric disorders. However, for disorders such as attentional deficit hyperactivity disorder (ADHD), schizophrenia, and post-traumatic stress disorder (PTSD) there are consistent evidence of a major implication of the dopaminergic and endocannabinoid systems.
Dopamine (DA) plays an important role acting as a trophic factor, in the development of neuronal cyto-architecture and also modulating neurodevelopmental processes during the embryonic and postnatal period. In particular, dopaminergic alterations within the prefrontal cortex (PFC) or Striatum, two brain area involved in cognition, learning and emotion, have been previously correlated to the etiology of neuropsychiatric disorders like schizophrenia, autism and ADHD. On the other hand, several studies have related dysfunctions of endocannabinoid system to psychiatric disorders. In fact, the relationship between cannabis consumption, especially during critical period of brain development, and schizophrenia onset has been demonstrated
