Emotional processing is a key function of the human brain, involving complex interactions between neural networks, cognitive mechanisms, and physiological responses. This review synthesizes current neuroscientific research on emotional regulation, focusing on the roles of the amygdala, prefrontal cortex, insula, and neurochemical pathways. It examines the influence of neurotransmitters and hormonal responses, particularly through the hypothalamic-pituitary-adrenal (HPA) axis, in shaping emotional experiences and responses. The review discusses empirical findings on the neurobiological mechanisms underlying emotion regulation and highlights their dysfunction in various psychological disorders, including anxiety, depression, post-traumatic stress disorder, and borderline personality disorder. In addition to summarizing key findings, this article identifies inconsistencies across studies and outlines directions for future research to better understand how emotional regulation processes vary across populations and contexts. Understanding these mechanisms is essential for informing effective interventions and improving mental health outcomes.