Which layer of the meninges is closest to the brain?

The layer of the meninges that is closest to the brain is the pia mater. This delicate membrane closely adheres to the surface of the brain and follows its contours, providing a protective layer. The pia mater is part of the three meningeal layers that cover the brain and spinal cord, which include the dura mater, the outermost layer, and the arachnoid mater, the middle layer.

Each of these layers serves specific protective roles and contributes to the overall function of the central nervous system. The dura mater is thick and provides a strong barrier, while the arachnoid mater is situated between the dura and pia, encompassing the subarachnoid space filled with cerebrospinal fluid. However, it is the pia mater that is directly in contact with the brain tissue, making it the closest layer to the organ itself.