The present invention relates to a method of determining whether a test compound is a proliferation-inducing or proliferation-inhibiting agent of ependymal neural stem cells. The method comprises: (a) contacting an ependymal neural stem cell with the test compound: and (b) determining the proliferation of the ependymal neural stem cell, wherein if the proliferation of the ependymal neural stem cell is increased in the presence of the test compound as compared to the absence of the test compound, the test compound is identified as a proliferation-inducing agent or wherein if the proliferation of the ependymal neural stem cell is decreased in the presence of the test compound as compared to the absence of the test compound, the test compound is identified as a proliferation-inhibiting agent.