 Further observations of young and old monkeys have proven that the younger subjects have thinner membranes with fewer layers of astrocytic processes while the older monkeys possess much thicker membranes.As of 2011, research is focused on the two-way communication between neurons and glial cells.Communication between these two types of cells allows for axonal conduction, synaptic transmission, as well as the processing of information to regulate and better control the processes of the central nervous system.