In biology, stability is important. From body temperature to blood pressure and sugar levels, our body ensures that these remain within reasonable limits and do not reach potentially damaging extremes. Neurons in the brain are no different and, in fact, have developed a number of ways to stabilise their electrical activity so as to avoid becoming either overexcitable, potentially leading to epilepsy, or not excitable enough, leading to non functional neurons.
While the first actual bionic man (or woman) might still be a ways off, the writers of the show might be impressed at this. A international team of researchers, have just taken an important step in the area of cell therapy: repairing the cerebral cortex of the adult mouse using a graft of cortical neurons derived from embryonic stem cells.