In our last blog, Rivers of Music Flow into the Mind, one of the contributing rivers we listed was a sense of space, and our movement within it.

We have no direct sense of space. There are no space sensors in our body — only indirect information from touch, sight, hearing.

The brain conducts a theater inside us (in the parietal lobe of the brain) which Arnold Trehub calls the retinoid space (The Theater of Consciousness), with ourselves in the center, in which 3D objects (and theoretically also time-based 4D objects) are constructed as models around us and then are “painted” with various multisensory attributes – sound, touch, taste – and displayed (become part of our consciousness).

• Part of this display preparation results from mathematical transformations of perceptual objects to compensate for viewing point (for example, turning ellipses caused by perspective into circles) or to perform imaginary mental changes such as mental rotation.
• The other part results from integration of the flow of multisensory and body information entering the theater through the thalamus structure, which is like a network of intelligent cables connecting all parts of the brain.

Other researchers with similar or overlapping views are Ravi Jerath & Molly Crawford, Marina Korsakova-Kreyn, Daniel Wolpert, and Daniela Dentico.

• Jerath & Crawford emphasize the role of the thalamus in creating consciousness and the images for display in the “3D theater.”
• Korsakova-Kreyn emphasizes the importance of supramodal (beyond individual senses) general processes for shaping our perceptions and mentally created objects, as in rotation transformations, which seem to treat musical and visual objects in a similar way.
• Wolpert says that brains are made for walking, so to speak, that is, motion control, not for purely perceiving or feeling. Animals have brains because they are mobile and need them. They need to know how to negotiate an environment, not just live in it. Plants do not need to do this. So he studies sensorimotor integration and finds this function is active in the inferior parietal lobe. Control of motion — and control of frame of reference — is vital in negotiating an environment, and that is what quaternions excel in computing. So I suspect that life forms learned how to tap the principles of quaternion relationships and operations in space through some handy analog process or mechanism involving organic structures, including molecules, that relate action to perceived and imagined movement — the logic of animal life.
• Dentico and associates demonstrate that electric flow of patterns from the occipital (initial vision-gathering) lobe during perception of real objects reverses direction during creation of imagined images, going from the prefrontal (planning) lobe to the parietal lobe (presumably for construction and awareness) and then to the occipital lobe (the reason is not clear).

One pattern that seems to emerge is that simple display function activity is correlated with the inferior region (IPL) of the parietal lobe, whereas motion-related activity, such as mental rotation or sensorimotor integration) is correlated with the superior region (SPL).

For references to a discussion of the work of these researchers, and a diagram of how they connect, see the following PDF file link to a 12-slide excerpt, Arnold Trehub and Related Researchers, from my presentation on a draft of The Culture of Quaternions.