The Somatovisceral Sensory System

Abstract

The sensory system discussed in this chapter encompasses cutaneous sensibility, the sensibility of the internal organs (visceroception or interoception) and the deep sensibility of muscles and joints (proprioception). The sensations mediated by the skin provide a link with the outside world. With the sense of touch we learn about the three-dimensional aspects of our surroundings; with the temperature sense we perceive warmth and cold; with the sense of pain (Chapter 10, p. 223ff.) we recognize potentially dangerous stimuli. Visceroception enables us to perceive something of our interior state — for instance, feelings of fullness, shortness of breath or heart pains. By proprioception we keep track of the positions and movements of our joints. However, not all of the sensory information from these sources is consciously perceived; it is also required for many regulatory processes of which we are unconscious. Proprioception and the tactile sense participate in motor coordination (see Chapter 5), temperature information is used in the automatic regulation of body temperature (see Chapter 25), breathing is controlled on the basis of information about the gas content of the blood, and painful stimuli elicit protective responses (see Chapter 5). It is by integration of the diverse items of sensory information from the skin and the joints that we create the subjective impression of our body as a whole, the body image. In this process, visceroception seems to play only a minor role.