 A final issue of dual-aspect approaches in general refers to the problem of panpsychism or panexperientialism, respectively (see the review by Skrbina 2003, and the entry on  panpsychism).  In the limit of a universal symmetry breaking at the psychophysically neutral level, every system has both a mental and a material aspect. In such a situation it is important to understand “mentality” much more generally than “consciousness”. Unconscious or proto-mental acts as opposed to conscious mental acts are notions sometimes used to underline this difference. The special case of human consciousness within the mental domain might be regarded as special as its material correlate, the brain, within the material domain.