Brain self-organization dynamics.

During early phases of brain development gene expression and postranslational modifications of gene expression are controlled by biochemical signals which are produced in a cellular microenvironment. Later in brain development there is a difference from the development of other organs because electrical signals are added to biochemical messengers as a further signaling in the self-organizing between genes and their respective environments. It must be considered that these electrical signals are capable in influencing gene expression and postranslational modifications. Electrical signals are transported by neuronal processes over distances and with highly topological selectively. This enlarges the range and complexity of the "environment" available to self-organization process. The "environment" relevant to brain self-organization includes all domains with which the evolving brain is capable to interact and from which it receives messages. The same electrical signals which convey messages are used by the brain as information carriers for computational process. The key concept in theories and modeling is that of refference. Cyclical process of emergent goal seeking, refference and sensory feedback constitute the basis for a subject consciousness. This cycle suggest further "inference" that the physiological basis of cause and effect lies in the mechanism of reafference. This tract results in the replacement of sensory stimuli by self-organization activity patterns that are contingent on past experience, present motivational state and expectancy of the future.