when do symptoms of axon damage show up
Diffuse axonal injury DAI is characterized by axonal separation, in which the axon is torn at the site of stretch and the part distal to the tear degrades. While it was once thought that the main cause of axonal separation was tearing due to mechanical forces during the trauma, it is now understood that axons are not typically torn upon impact; rather, secondary biochemical cascades, which occur in response to the primary injury (which occurs as the result of mechanical forces at the moment of trauma) and take place hours to days after the initial injury, are largely responsible for the damage to axons.[13][14][15]