Section 4, Chapter 1, Neural controls for the muscles that control the actions that enable vision

In the previous two sections we discussed walking and turning on a stage to illustrate how physical action can be analyzed in terms of the movement of bones and joints. In this section we shall analyze vision. In the first chapter we shall discuss how action is required to make purposive vision and perception possible.

For supporting the actions required to be successful for evolution, vision has to be purposive or goal oriented. It helps to detect food, possible enemies, and mates.

The actions involve turning the head, opening the eye lids, turning and focussing the eyes.

The closest analogy is the control of a video camera, with tilt, pan, and focusing.

• The concept of paying attention likely differs from starting and stopping the camera.
• Zoom controls are generally not available
• Stereo images are available (2 eyes a known distance apart)
Diagram 1: Visual representation of the causal chain from neural information to muscle movement to eyeball rotation to direction of vision to visual information.