In this continuum, cell death occurs as hybrids ranging from apoptosis to necrosis (Figs. 4 and 5). We found that the death of neurons is not always strictly apoptosis or necrosis, according to a traditional binary classification of cell death. Neuronal death also occurs as intermediate or hybrid forms of cell death with coexisting characteristics (Fig. 5) that lie along a structural continuum with apoptosis and necrosis at the extremes (6,7). It appears that the maturity of the brain and the subtype of glutamate receptor (GluR) that is activated influence cell death along this continuum (6,7).