A method for treatment of a brain and/or spinal cord includes inserting a flexible catheter into a cerebrospinal fluid space, the flexible catheter including two lumens adapted to allow a fluid to circulate therein in a closed loop within the flexible catheter and the flexible catheter being adapted to be connected to a device for cooling and circulating the fluid. The cerebrospinal fluid in the cerebrospinal fluid space is cooled with the flexible catheter to enable selective central nervous system cooling. The functional status of the brain and/or spinal cord is monitored, and the treatment of the brain and/or spinal cord is modified to adjust for any change in the functional status of the brain and/or spinal cord.