Extended consciousness is said to arise in the brain of animals with substantial capacity for memory and reason. It does not necessarily require language. The perception of a historic and future self arises from a stream of information from the immediate environment and from neural structures related to memory.
A neurology department chairman from University of Iowa College of Medicine popularized the concept. Antonio Damasio theorized extended consciousness to arise in the structures in the human brain he described as image spaces and dispositional spaces.
Image spaces imply areas where sensory impressions of all types are processed, including the focused awareness of the core consciousness. Dispositional spaces include convergence zones, which are networks in the brain where memories are processed and recalled, and where knowledge is merged with immediate experience.
Image processing in the cerebrum is regionally specific to various senses, but is highly distributed and interconnected, with images such as visual, spatial and perhaps linguistic impressions stored in diverse areas then assembled when recalled as a thought. Likewise, neural convergence zones are widely distributed in the lobes of the cerebral cortex.
While humans are theorized to share extended consciousness with some animals, theorized neural mechanisms for extended consciousness do not provide answers to philosophical or cosmological questions about consciousness such as why we perceive ourselves as a limited part of a larger universe.