PSYCHOPHARMACOLGY:

There are three layers of meninges that cover the brain and the spinal cord. These are (14): Pia matter. Arachanoid layer. The dura matter. The innermost of the layers is called the pia meter, which tightly encloses the brain. It is rich in blood vessels. The arachanoid layer is situated outside the pia matter and looks like a thin layer of web. ................
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