South Korean scientists said Thursday that they have developed a way to allow drugs to reach the brain that could lead to a safe and cheap treatment method for various neurological diseases. A Korea Advanced Institute of Science and Technology (KAIST) team led by bio and brain engineering professor Choi Chul-hee said it had used an ultra-high frequency laser to temporarily weaken the \"blood-brain barrier,\" which permitted treatment drugs to reach unhealthy parts of the brain in laboratory tests.