Living Under Threat: Stress as a Mediator Between Community Violence and Mental Health in the Arab Society in Israel.

Parkinson's disease (PD) is characterized by dopaminergic hypofunction in the basal ganglia, which is considered to lead to typical motor symptoms of PD. However, PD is increasingly considered a multisystem neurodegenerative disease including also various non-motor symptoms, such as sleep and autonomic nervous system disturbances, anxiety, depression, and psychiatric symptoms. In addition, a broad spectrum of cognitive symptoms, ranging from mild cognitive impairment in PD (PD-MCI) to PD dementia (PDD, has been described. The endocannabinoid system (ECS) is a widespread neuromodulatory system that plays an important role in various neurophysiological functions, such as motor control, synaptic plasticity, and neurodevelopment, but also in cognitive processes and the regulation of mood and emotions. Type 1 cannabinoid receptors (CB1R) are the most abundantly expressed cannabinoid receptors in the brain and are found in high densities particularly in the basal ganglia. Various pre-clinical studies suggest that cannabinoid agonists impair working memory and long-term memory formation, whereas cannabinoid antagonists and inverse agonists may enhance learning and memory. Additionally, cannabinoid receptor activation is shown to decrease anxiety and have antidepressant activity.