The three-dimensional “AIM model” proposed by Hobson et al. is imaginative. However, many kinds of data suggest that the “dimensions” are not orthogonal, but closely correlated. An alternative view is presented in which mental functioning is considered as a continuum, or a group of closely linked continua, running from focused waking activity at one end, to dreaming at the other. The effect of emotional state is increasingly evident towards the dreaming end of the continuum.

[Hobson et al.; Nielsen; Solms]