How you see color, part 3

So if light is just a wave of energy, how do we see color? How do we see at all?




You eyeball has specialized cells called cone cells. Cones come in three different types. Each type is sensitive to a different wavelength on the spectrum. The cones are usually referred to as short, medium, and long, often shortened to S, M, and L, for the length of the electromagnetic waves they sense.



You might think that the three types of cones must see red, blue, and yellow, the three primary colors. However, these colors don't really correspond nicely to colors. L cones, for instance, are sometimes referred to as red receptors. Actually, they are closer to green-tinged yellow. The other cones, likewise, do not easily match up with primary or secondary colors. As a matter of fact, cones' light perception varies from person to person. The different cones' are sensitive to overlapping ranges of light, which is what lets us sense the variations.



The genes for sensing visible light are carried on the X chromosome. That is why color blindness is more common in men, and why some women have an extra type of cone, which can allow them to see light beyond what is visible for most people.



In lower lights, different cells, called rods, sense light. Rods don't have much to do with color differentiation though.



Intensity and amount of light is what determines the saturation of color. Saturation describes how dark or pale a color is.



Once the cones – and to some extent, rods – have absorbed the light, the nerves send that information to the brain, which puts the information together to form the images that you see. Interestingly, the inside of the eye sees the image in front of you upside down, and the brain has to flip it back right-side up in order to be useful to you in navigating the world.

Microchips and photonchips

Earlier this week, Google celebrated the co-creator of the first microchip with one of their Google Doodles. A microchip is defined by Wikipedia as "an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material."




I'll be honest, I read that a few times, and all I got was tiny thingamajig with some tiny conductor thingies that makes computers and the like work. Computers, cell phones, and other digital products couldn't work without them. Various microchip-esque ideas came and went between 1945 and 1958, when the first working microchip was created by Jack Kilby. They have come quite a ways since then. Moore's Law states that (in the long term) the number of circuits that can be inexpensively fit on a microchip of equal size doubles every two years.



Now, a new advance may put Moore's Law in the past. A new chip is in development which manipulates individual photons of light, guiding them and also containing and initiating their interactions. These tiny pathways on a silicon chip represent a huge step towards a quantum computer. Is anyone else thinking about the wonders of tomorrow-land?

How you see color

The human eye sees a wide spectrum of visible light - black to white and blue to red. While the keys on a FunKeyBoard are several colors, the fact is, the light is colored, and the keys just reflect that light.




Sunlight, lamplight, headlights...This light is all more or less clear, or white to the eye. White light is actually a combination of all colors in the visible spectrum. You've probably seen a prism split that white light into a rainbow, displaying the whole spectrum of visible light separately. Rainbows work the same way, with water droplets acting as prisms.



When you look at something, you perceive its color - unless you are colorblind, or course. A FunKeyBoard has a red case. What that means in terms of how you see the color is that the material it is made of reflects the red light. The reflected light is the light your eyes take in. The FunKeyBoard's case actually absorbs all of the colored light except red.



The keyboad that is on my laptop is black. It is reflecting back none of the colors of visible light, absorbing all frequencies. In actuality, it is not a pure black, which would reflect no light at all. Theoretically, a black hole would be the best example of a real black.

Recent studies find Autistic brain develops more slowly in some ways - performs better in others

Autistic children are usually (though by no means always) diagnosed in their early childhood.  New research from UCLA, however, indicates that brain development experiences delays into the teen years.  These findings could help account for some of the symptoms of autism experienced by many individuals in this age range.  The parts of the brain that are involved in learning, emotional processing, language, and social skills appear to develop more gradually in autistic preteens.  Often, autistic children experience difficulties with socializing, particularly in this already difficult period of their lives. 

While these new findings help researchers understand (and in the future, possibly ease) some of the difficulties autistic individuals experience throughout their life cycles, one should not take slower brain development in some areas to mean defective or inferior.  Particularly, areas like reasoning tend to be better developed in individuals who have been diagnosed with autism.  This is not limited to so-called “savants.”  While autistic individuals often score poorly on standardized tests or have difficulty communicating, those who know them well would probably tell you that many people with autism are incredibly smart, just not in a way that easily translates into what is “normal,” which is why autism was considered a defect for many years.  

Nurture vs Nature - Autism

The cause of autism and ASD has been a topic for much discussion, research, and debate for years, more so as the prevalence of this disorder increases.  There has recently been a quantity of research regarding genetic links to ASD.  In fact, in a post from last month, I discussed a couple of these studies, which were finding more solid links between certain genes and proteins and autism.

Today a new study reports a more tangible link to environment in development, as well.  Often, children in a family are more likely to have autism if another family member also has it.  This study on twins and families indicated that up to 55% of the cause of autism may be environmental.  While this seems to be contradictory to the previous studies, it is not.

It is becoming more and more clear that autism is not simply something you are born with, an "in your genes, if you have it you have it and there's nothing to be done" disorder.  Instead, while ASD is certainly linked to genetics, it is also largely influenced by environment.  A child with the genetics that say he or she may have ASD will not necessarily develop autism.  Instead, whether or not they present autistic symptoms may be determined by other factors.

Think of it like this.  Everyone who gets speeding tickets and traffic violations has (or had) a vehicle, or at least used one.  However, not everyone who has a vehicle gets traffic violations.  Having the vehicle is necessary to the ticket, but is not the sole factor.

Likewise, it is appearing more and more likely that while genetics may determine who is at risk or likely to develop ASD, environment plays a role as well, possibly even in larger part than genes.  When it comes to ASD, nature and nurture work together to decide if an individual will begin displaying autistic symptoms or not.

The Science of Autism

Individuals on the autism spectrum range from high functioning with a few mannerisms to those who face severe challenges in everyday life.  With the number of cases seeming to continually increase, research into autism has also increased.  While they have yet identify the cause of autism, there has been a fair amount of progress in recent years.

There are dozens of “suspect genes” that researchers have identified as possibly relating to autism.  In recent research, different groups of scientists have identified that it is not the genes themselves that may be part of the cause of autism, but rather the proteins they produce.  There are an extraordinarily large number of proteins at work in the human body and brain.  The way certain proteins interact indicates that they may be related to autism.

Both findings suggest that different types of autism may share a common pathway even when they occur in distinct syndromes or alone—something that wasn't clear just from looking at the genes.  These common pathways are hopeful targets for drug development, Zoghbi says. "Our interactome is only a first step, but it could lead to a framework to investigate new genes and test new drugs."

 Another study indicates that this is not just an effect of autism, but possibly the cause.

Two other clear-cut patterns emerged when the scientists compared the autistic and healthy brains. First, the autistic brain showed a drop in the levels of genes responsible for neuron function and communication. Second, the autistic brain displayed a jump in the levels of genes involved in immune function and inflammatory response. "By demonstrating that this pathology is passed from the genes to the RNA to the cellular proteins, we provide evidence that the common molecular changes in neuron function and communication are a cause, not an effect, of the disease."

This is incredibly exciting news for individuals affected by ASD, autism spectrum disorder, and hints that there may be a more effective treatment for autism in the future.

Computers

Computer is a very ancient term, which originally referred to individuals who performed calculations or computations.  It was not until the end of the 19th century that it started to obtain is modern connotations.  Computers today are capable of thousands of functions, all derived from a digital, binary code.  Interestingly, this code is remarkably like the code of DNA, which contains four variables instead of the two which computers use. 

 

The ENIAC is considered the first general use, programmable computer.  It was created in 1946 to calculate artillery firing tables, but was first put to use making calculations for the hydrogen bomb.  Referred to as the "Giant Brain," ENIAC reached speeds that have yet to be matched.  At  680 square feet, ENIAC was a hulking predecessor of modern technology.

 

Before the ENIAC, there was the advent of the Turing Machine, which "is a theoretical device that manipulates symbols on a strip of tape according to a table of rules," according to wikipedia.  While not a practical computing device, all modern computers are descendants of the Turing machine. 

Earlier still, the first data to be read by computers was on punched paper cards.  This revolution in computer science was used to tabulate the 1890 census.  This technology was originally made to create automatic patterns in weaving.  Joseph Marie Jacquard developed the punched card system in 1801.  It was the first instance of programmable technology in action. 

Earlier yet, ancient mechanical computers included the abacus, the slide rule,and the astrolabe.  More impressive is the Antikythera mechanism, an early analog computer device that was probably used to calculate the position of sun, moon, and planets, predict lunar and solar eclipses, track the rise and set of major stars, and keep the  Metonic, Saros, and Exeligmos cycles, which are used in fixing calenders and range from 18-54 years.  The device is now known to have at least 37 gears, was small enough to be portable, and had  a built-in instruction manual.  It is thought to have been made based on designs of Archimedes, and probably was one of several similar devices, all dating back to approximately 100 BC.

Yes, the computer you are reading this on has come a long, long way.  Amazing how technology has made such leaps, and how it continues to stretch forward.