Communication with the outside world
So far we have been focusing on the networks of nervous and endocrine communication within the body. These help to maintain the integrity and viability of the multicellular organism. To complete this section, let us briefly look at the broader picture of how the whole person interacts with their surroundings.
We have seen that there is a pattern linking our activities that can be summarised thus: sense - process - do. This pattern can be applied to the cellular level and levels above. For example, we have different types of sensory receptors that respond to a variety of incoming stimuli, and that information is relayed to the central nervous system for processing. Then some appropriate response is initiated in muscles and glands. At its simplest this pattern of communication is seen in reflex arcs, and at its most complex the quality of consciousness is involved.
At the whole-person level, this repertoire of activities can be very complex. Muscular movements in the larynx, pharynx, and mouth can result in the production of sounds - speech, singing, shouting, whispering. Movements in the facial muscles can communicate expressions of joy, despair, puzzlement, and curiosity. Facial expressions, vocalisations, even body language allow us to communicate our thoughts, moods, and attitudes to others, just as we read these signs in others. Through these interactions - not only with other people, but also with other living and non-living systems - we develop our understanding of the world and our place within it.
That completes our brief look at communication and responsiveness. The only thing left to do now is to place all these different activities we have looked at into the context of the human lifecycle.