Traditionally, the five special senses have been defined as taste, smell, sight, hearing and feeling. However, touch is now considered to reflect the activity of the general senses, and equilibrium, or balance, can be thought of as a new fifth special sense. In contrast to the general sensory receptors, most of which are modified dendrites of sensory neurons, the special sensory receptors are distinct receptor cells. They are either localised within complex sensory organs such as the eyes and ears, or within epithelial structures such as the taste buds and olfactory epithelium.

The principle function of the special sensory receptors is to detect environmental stimuli and transduce their energy into electrical impulses. These are then conveyed along sensory neurons to the central nervous system, where they are integrated and processed, and a response is produced.

As part of the Physiome Project, the Eye Modelling Research Group at the Bioengineering Institute is aiming to develop an anatomically based and biophysically accurate integrated model of the eye. The initial stage of this project is to model fluid flow in the mammalian lens. The completed model will includes a range of spatial and temporal scales, from the level of the protein and cell, to the whole organ, and ultimately it will be integrated with other the organ systems in the Auckland Bioengineering Institute’s virtual human.