Figure 4.

(Figure illustrated by Jessamyn Camille Reddy, adapted from; [1] p. 26, permission obtained) Model of glymphatic function in Young, Old and Alzheimer’s disease. In young people, CSF travels along periarterial routes, entering the brain parenchyma, and washes solutes and waste products into the veins. In older people, the loss of AQP4 water channels will result in reduced glymphatic clearance. In those with Alzheimer’s disease, the accumulation of amyloid-beta impairs fluid movement within the interstitial space, decreasing glymphatic clearance.