Two aspects of consciousness are first considered: consciousness as awareness (phenomenological meaning) and consciousness as strategic control (functional meaning). As to awareness, three types can be distinguished: first, awareness as the phenomenal experiences of objects and events; second, awareness as meta-awareness, i.e., the awareness of mental life itself; third, awareness as self-awareness, i.e., the awareness of being oneself. While phenomenal experience and self-awareness are usually present during dreaming (even if many modifications are possible), meta-awareness is usually absent (apart from some (...) particular experiences of self-reflectiveness) with the major exception of lucid dreaming. Consciousness as strategic control may also be present in dreams. The functioning of consciousness is then analyzed, following a cognitive model of dream production. In such a model, the dream is supposed to be the product of the interaction of three components: (a) the bottom-up activation of mnemonic elements coming from LTM systems, (b) interpretative and elaborative top-down processes, and (c) monitoring of phenomenal experience. A feedback circulation is activated among the components, where the top-down interpretative organization and the conscious monitoring of the oneiric scene elicitates other mnemonic contents, according to the requirements of the dream plot. This dream productive activity is submitted to unconscious and conscious processes. (shrink)

The question that we deal with in this commentary is the need to clarify the synergistic role of different non4) with REM and while awake in elaborative encoding of episodic memory. If the assumption is that there is isomorphism between neuronal and cognitive networks, then more detailed analysis of NREM sleep and dreams is absolutely necessary.

Dreaming can be explained as the product of an interaction among memory processes, elaborative processes, and phenomenal awareness. A feedback circuit is activated by this interaction according to the associative links and the requirements of the dream scene. Recently, it has been hypothesized that a partial similarity exists between dreaming and mind wandering and that these two processes may involve the same neural default network. This commentary discusses the differences and similarities between phenomenal consciousness during dreaming and phenomenal consciousness during (...) mind wandering from the perspective of the “continuity” of engagement of cognitive systems. The greatest difference consists in the lack of reality testing during dreaming. Dream imagery is hallucinatory by nature. Consequently, the simulated world in dreams makes dream imagery more akin to perception. In contrast, the imagery of mind wandering is more similar to imagination. The level of meta-awareness is preserved more frequ... (shrink)

Autoscopic phenomena are complex experiences that include the visual illusory reduplication of one’s own body. From a phenomenological point of view, we can distinguish three conditions: autoscopic hallucinations, heautoscopy, and out-of-body experiences. The dysfunctional pattern involves multisensory disintegration of personal and extrapersonal space perception. The etiology, generally either neurological or psychiatric, is different. Also, the hallucination of Self and own body image is present during dreams and differs according to sleep stage. Specifically, the representation of the Self in REM dreams (...) is frequently similar to the perception of Self in wakefulness, whereas in NREM dreams, a greater polymorphism of Self and own body representation is observed. The parallels between autoscopic phenomena in pathological cases and the Self-hallucination in dreams will be discussed to further the understanding of the particular states of self awareness, especially the complex integration of different memory sources in Self and body representation. (shrink)

Nielsen's model presents a new isomorphic brain-mind viewpoint, according to which the sole dream generator is found in a REM-on (explicit or covert REM) mechanism. Such a model cannot explain the dreamlike activity during SWS (slow wave sleep), SO (sleep onset) and in the last period of sleep. Moreover the hypothesis contrasts with Solms's data, which show that dreaming is present also in case of destruction of the REM generator. [Nielsen; Solms].