Before we get into this, I came across an article which brought home to me the complexity of the information I present and try to explain. The particular article had nothing to do with what this effort is about. It was, instead, a tirade (?) about how Wikileaks was actually colluding with the Russians by presenting lines of code which the author said definitely proved her point. In so doing she presented lines of code, first in full, and then simplified for us illiterate hicks. Well, I looked at the presentation intently. I reread the central (data) part of the article again, and concluded that she might be proving the sky was blue. Now she may be right, or not. The point is that to most of you, even those who code, much of the neuroanatomy, physiology and physics will seem like bafflegab, no matter what I do to clarify it. I'll do my best. After all I've had 40 years of explaining Medicalese in people talk.

Thus, should those of you who venture down this page, not understand anything or even a little tid bit, please add your observations in the commentary.

In part 1 of this essay, there is mention of using near-infrared as the sensor by which to remotely "scan" if you will, brain activity. So we need a little background in this, which will be presented shortly.

Principle of knowledgeable, animate or computer, action:

Gathering information = sensing
Using information = effectuating that information for an intended goal.

At both points in this chain are invariably problems. For instance, regarding sensing, is the perception correct? Is the entire subject of interest perceived? Is the most efficacious manner (modality) of sensing being used? How does motion affect sensing? How do light or sound affect sensing?

Regarding effectuating the problems are somewhat similar regarding the targeting of the appropriate thing for action. As mentioned above, the target may be incompletely perceived or falsely perceived. Even if the target is correctly defined mishaps may occur. Inaccurate guidance of energy may be caused by motion, light, noise, absence of a stable platform from which to act.

Certain actions require no sensing, such as lightening or meteor strikes. But these require absolutely no knowledge of the target at all. The action just is, regardless of the discharge. Random, perhaps, perhaps not. Consider the Pleiades annual meteor shower which can be predicted years in advance. But which one of those whirling rocks is gonna come crashing where is not determined by those rocks.

Bacteria have sensing. Viruses have sensing. Politicians ostensibly have sensing. I know little about computer sensing, such as the web cam and microphone and keyboard (or even touch and possibly odor detection).

Sensing is vital for a sustainable species: virus, bacteria, monkeys. I did however come across something of interest recently concerning sensing in monkeys:

Okay, recess is over, back to work!

These two pictures are used to give you an idea why I concentrate so much on infrared sensing. After that we will study optics.

The very basics here:

Now a close up view:

Infrared

Learn about infrared.

Infrared radiation, or simply infrared or IR, is electromagnetic radiation (EMR) with longer wavelengths than those of visible light, and is therefore invisible, although it is sometimes loosely called infrared light. It extends from the nominal red edge of the visible spectrum at 700 nanometers (frequency 430 THz), to 1000000 nm (300 GHz)[1] (although people can see infrared up to at least 1050 nm in experiments[2][3][4][5]). Most of the thermal radiation emitted by objects near room temperature is infrared. Like all EMR, IR carries radiant energy, and behaves both like a wave and like its quantum particle, the photon.

Infrared radiation is used in industrial, scientific, and medical applications. Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected. Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space such as molecular clouds, detect objects such as planets, and to view highly red-shifted objects from the early days of the universe.[8] Infrared thermal-imaging cameras are used to detect heat loss in insulated systems, to observe changing blood flow in the skin, and to detect overheating of electrical apparatuses.

Infrared: wavelength and frequency compared:

Infrared compared to light and other spectra:

Abbreviated list of infrared, etc. physics and usage:

This completes the infrared section but I haven't even touched on much which is clinically relevant. Clinical relevance, actual and potential, will be discussed in part 4.