FIGURE 3.

A, The Perturbational Complexity Index (PCI) as a marker of consciousness in different clinical conditions and states. Adapted from Casali et al. ⁹⁷ VS = vegetative state, MCS = minimally conscious state, EMCS = emerging from minimally conscious state. A key question is what is the range of consciousness as measured by PCI in people with severe Alzheimer's disease (AD)? B, Orthogonal activation in auditory, visual, and fronto‐parietal networks in response to watching a film. This has been used to demonstrate presence (Patient 2) or absence (Patient 1) of covert awareness in minimally conscious states and could be used similarly in people with severe AD. Adapted from Naci et al. ¹⁰¹