Religion/spirituality and neuropsychiatry

SUMMARY In this chapter, we review the neurobiological basis of spirituality and related religious experiences. We first focus on regions of the brain associated with mystical and spiritual experiences showing that increased activity in the frontal and temporal lobes is a key component of such practices. We then explore serotonergic and dopaminergic systems in measures of spirituality. In this field, we mainly explore association studies between genetic polymorphisms and spirituality as a personality trait. These studies strongly suggest a higher activity of serotonergic and dopaminergic systems in individuals with high spirituality. We then propose a model encompassing both religious activities and measures of spirituality in connection with serotonergic and dopaminergic systems. This explanatory model could help to understand the complex link between psychiatric disorders and spirituality. INTRODUCTION Spiritual experiences, religion, and rituals may be viewed as the result of the evolutionary changes in the brain that have led humans to socialize and to form communities and societies. Within the evolutionary perspective, spirituality or religiousness could be seen as an advantageous tool for human beings over other species. This could be understood as a complex neurochemical process occurring in the brain. This view has led researchers to explore the brain's neurochemical activity to explain some of the spiritual processes we experience. However, dealing with the neurobiology of religious and spiritual experiences is a complicated and difficult task.