Figure 4.

A neural model of the HIV‐associated neurocognitive disorders (HAND) severity. This model was inspired by research in Alzheimer's disease (Jack & Holtzman, 2013). As in the Alzheimer's disease model, the degree of neural injury was very hypothetical and was used to illustrate the potentially different degree of injury to different regions. The potential overlaps between different HAND stages were shown. One novel and specific prediction of this model is the transition from pre‐ANI to ANI that happens when the injury to the caudate/striatum/subcortical becomes prominent (i.e., overweighs the injury to the frontal/ACC). It is worthwhile to note that injury to other key regions such as the hippocampus and cerebellum might be prominent as well, probably even more than the frontal at more advanced stages of HAND, such as HIV‐associated dementia (HAD) (Moore et al., 2006). ACC: anterior cingulate cortex; ANI: asymptomatic neurocognitive impairment; CN: cognitively normal; MND: mild neurocognitive disorder