Boston-based start-up Spritz aims for the sky with its recently announced mobile application, which, according to the developers, will drastically change the way we read. Forget about sentences, paragraphs, and layout. Spritz fires text directly at your eyes, one word at the time, at a break-neck speed. The motivation behind this presentation mode is straightforward: The eye movements that we make during reading are just a waste of time and energy. Remove these eye movements from the equation, and our reading pace easily doubles–or even quadruples–without much extra effort. With hardly any practice, anyone should be able to “spritz” at an astonishing rate of a 1000 words per minute. The prospect of devouring The Hobbit in merely one-and-a-half hour made Spritz go viral on the Internet. Even though the application is yet to be released, the world seems ready to welcome it with open arms.

But is the hype justified? Here, we take a critical look at the science behind this reading of the future.

Getting rid of eye movements

Even though reading doesn’t seem to take much effort, our brain needs to work-out heavily to process the enormous amount of text that we are confronted with every day. Indeed, reading is a very complex exercise. For one thing, our eyes do not stop to process each word of a sentence individually. Instead, our brain strategically picks the next position for our eyes to fixate on, and only then programs the eyes to jump …

Scientists should do lots of things. Just search for #openscience on Twitter. It’s buzzing with reform!

Scientists should make their papers freely available, and no longer hide them behind the paywalls that are put up by commercial publishers. They should make their datasets available, so that analyses can be independently verified. They should post their ongoing work to pre-print servers (as many from the exact sciences already do), where it can be discussed, shared, and debated without unnecessary publication delays. They should spend more time replicating each others findings. They shouldn’t care about journal impact factors, but judge quality on a per-manuscript basis, using altmetrics. And the list goes on!

Sharing can be a little scary at first. But a young generation of scientists is doing it more and more. (Source)

But despite all the buzz, actual scientific practice has hardly changed. And I’m at fault here as much as anyone. I’ve written a few blogs on the subject, but I haven’t really conducted much #openscience at all. So, with our new-years resolutions fresh in mind, my colleagues and myself decided to put our money where our mouth is, and take the ‘high road’ to what will hopefully become our next publication.

As a first step, I posted all experimental materials to a GitHub repository. You can think of GitHub as a public DropBox with infinite history. All versions of all files within a specific project remain available, and you can easily inspect the changes …

Mantis shrimp are are colorful little critters. Especially in their own eyes.

Animals are able to perceive color because the eyes contain different types of light-sensitive cells, or photoreceptors, each of which is most sensitive to a different part of the visible-light spectrum. Human eyes have three such photoreceptors, with a peak sensitivity to greenish, blueish, and reddish light. (There is also a fourth type of photoreceptor, which is used mostly for peripheral vision, and vision in darkness.) In other words, humans are trichromatic. The tri in trichromatic doesn’t mean that we perceive only three colors, but that all colors that we perceive can be reduced to a mixture of three colors (see also my post on color vision).

Most other mammals, as well as colorblind humans, have only two types of photoreceptors for color vision, and are therefore bichromatic. Most birds, on the other hand, are tetrachromatic (i.e. four photoreceptors for color vision), and therefore have a slightly more colorful visual palette than we do. But the variation between species is relatively small: Most animals have two to four types of photoreceptors for color vision. And there is good reason for this evolutionary agreement: Two to four photoreceptors are all that is needed to capture the colors that are actually present in the environment. Adding a fifth photoreceptor does relatively little to improve color vision.

Source: National Geographic

But the Mantis shrimp is a remarkable exception. This coral-reef-dwelling crustacean is endowed with 12 to 21 different types …

The eye is a jelly-filled chamber with a lens in front of it. This lens focuses light onto the retina, in the back of the eye, from where nerve impulses are sent to the brain. But the eye’s lens is an imperfect device. For example, different colors have different focal lengths. This means that if you focus on the blue stripe of Newman’s Who’s Afraid of Red, Yellow and Blue, the yellow and red stripes will be ever so slightly out of focus. This and other types of distortion are most pronounced for large lenses, so it is best to keep the surface of the lens as small as possible. For this reason, most of the eye’s lens is covered by the colorful iris, which serves more than just an aesthetic purpose. And the part that is not covered by the iris is your pupil.

Who’s afraid of red, yellow, and blue?

But there is also downside to having small pupils: They don’t let a lot of light through. This doesn’t matter when you are in a bright environment where even tiny pupils let through sufficient light. But in darkness small pupils simply won’t do: Optical distortions or no, in darkness pupils must increase their size in order to let through the bare minimum of light that is required for vision.

So there are two opposing forces that together determine the size of your pupil. On the one hand, small pupils suffer …

Like workers from all trades, scientists produce things. Bakers produce bread, construction workers produce buildings and such. And we scientists… well, we produce p values that are smaller than .05.

So what exactly is a p value? If a scientist wants to prove a point, she generally does so by testing a hypothesis. For example, she might hypothesize that rich people are happier than poor people. She could test this hypothesis by collecting happiness ratings from fifty rich and fifty poor people, and calculate a p value for the difference. The p value then expresses the chance that these happiness ratings would be as different as they are, or more different, if rich and poor people were really just as happy. (For a more detailed discussion, see my previous post.)

Are you still with me? Maybe not, but no matter: The important point is that a low p value means that your hypothesis is probably correct. (Actually, it means that the data is unlikely given the null hypothesis, but let’s skimp over this important detail for now.) The commonly accepted threshold is .05: If your p value is below .05, you have found something worthy of publication, otherwise you haven’t.

So there is a clear incentive for scientists to find p values that are smaller than .05. So what do yo do if you get a p value of .051? Well, you do what any sensible scientist would do: You test a few more participants, analyze the data …