Human embryonic stem cells or hESCs could go a long way in giving relief from degenerative diseases by multiple mechanism invoking. These cells can be grown without the requirement of animal feeder layers or immunosuppression. In order to highlight the effectiveness of stem cells the researchers used mouse neural stem cells for establishing the parameters of what could be achieved. The researchers also studied the stem cells of human origin and compared both the cells in order to highlight the usefulness of human embryonic stem cells in treatment of degenerative diseases and preservation of human life. The researchers were able to figure out that the implanted neural stem cells contributed much more than just replacement of brain tissues destroyed by the disease and some of the nerve cells which were replaced even transmitted nerve impulse hence suggesting that stem cell derived could integrate functionally into a diseased brain.