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Brainworks: Explaining Optical Illusions and Other Mental Tricks

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Back during the summer, an early copy of Brainworks showed up in our office. National Geographic was planning to advertise the book in mental_floss magazine (and this was even before we kept popping up on Curb Your Enthusiasm). I got sucked into the optical illusions featured throughout the book and asked if I could reprint a few of the explanations behind them. They agreed. Here you go!

Shepard's Tables

The horizontal/vertical illusion dates to its description in German physiologist Adolf Fick's 1851 doctoral thesis. He demonstrated differences among simple geometrical properties and how they are perceived. These kinds of disparities are called geometrical-optical illusions.

Fick observed that a vertical line looks longer than a horizontal line of the same length. This is easily seen in the letter T when the horizontal and vertical strokes measure precisely the same length, or when two line segments of exactly the same dimension form a right angle with one segment horizontal and the other vertical.
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Another explanation rests on an illusion of perspective. The brain chooses to interpret the drawing as two tables. Applying the rules of perspective it has formed through experience, the brain views the table on the left as receding farther, and being longer, than the one on the right.

The Arrow Illusion

Compare the tables with the Müller-Lyer Illusion (or Arrow Illusion). It is named for Franz Carl Müller-Lyer, a 19th-century German psychiatrist and sociologist. He began his illusion by drawing two parallel lines of the same length. At the ends of one line, he placed two arrowhead shapes with their open ends pointing outward. At the ends of the other line, he placed the same two arrowhead shapes with their open ends pointing inward. The line segment with the arrowheads pointing inward and the ends open to the outside looks significantly longer than its mate. The illusion holds true with the line segments in any orientation.

The Ames Room

American psychologist Adelbert Ames used his background as a painter to create an elaborate trick on the brain: the construction of a distorted room that looks normal when viewed from front and center. The back wall of the room slants away from the viewer instead of lying perpendicular to the viewer's line of sight, but Ames compensated for this by using perspective cues to make the room appear normal. A person who stands at the most distant corner of the sloping wall appears tiny, with plenty of space overhead; the same person standing in the nerer corner crowds the ceiling like a giant. An adult on one side is dwarfed by a child on the other because both appear equidistant from the viewer. The key to this illusion is that perspective and one particular angle make the room appear perfectly rectangular and normal.

If you like this kind of thing, check out the book's site. Here's the description: "You'll see for yourself why these visual illusions and experiments hoodwink the brain. You'll find out how the structure of the eye influences what you see. And you'll think of events that may not have actually happened, in order to learn how the mind can create a false memory."

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A Simple Way to Charge Your iPhone in 5 Minutes
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Spotting the “low battery” notification on your phone is usually followed by a frantic search for an outlet and further stress over the fact that you may not have time for a full charge. On iPhones, plugging your device into the wall for five minutes might result in only a modest increase of about three percent or so. But this tip from Business Insider Tech may allow you to squeeze out a little more juice.

The trick? Before charging, put your phone in Airplane Mode so that you reduce the number of energy-sucking tasks (signal searching, fielding incoming communications) your device will try and perform.

Next, take the cover off if you have one (the phone might be generating extra heat as a result). Finally, try to use an iPad adapter, which has demonstrated a faster rate of charging than the adapter that comes with your iPhone.

Do that and you’ll likely double your battery boost, from about three to six percent. It may not sound like much, but that little bit of extra juice might keep you connected until you’re able to plug it in for a full charge.

[h/t Business Insider Tech]

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Trying to Save Money? Avoid Shopping on a Smartphone
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Today, Americans do most of their shopping online—but as anyone who’s indulged in late-night retail therapy likely knows, this convenience often can come with an added cost. Trying to curb expenses, but don't want to swear off the convenience of ordering groceries in your PJs? New research shows that shopping on a desktop computer instead of a mobile phone may help you avoid making foolish purchases, according to Co. Design. Ying Zhu, a marketing professor at the University of British Columbia-Okanagan, recently led a study to measure how touchscreen technology affects consumer behavior. Published in the Journal of Retailing and Consumer Services, her research found that people are more likely to make more frivolous, impulsive purchases if they’re shopping on their phones than if they’re facing a computer monitor. Zhu, along with study co-author Jeffrey Meyer of Bowling Green State University, ran a series of lab experiments on student participants to observe how different electronic devices affected shoppers’ thinking styles and intentions. Their aim was to see if subjects' purchasing goals changed when it came to buying frivolous things, like chocolate or massages, or more practical things, like food or office supplies. In one experiment, participants were randomly assigned to use a desktop or a touchscreen. Then, they were presented with an offer to purchase either a frivolous item (a $50 restaurant certificate for $30) or a useful one (a $50 grocery certificate for $30). These subjects used a three-point scale to gauge how likely they were to purchase the offer, and they also evaluated how practical or frivolous each item was. (Participants rated the restaurant certificate to be more indulgent than the grocery certificate.) Sure enough, the researchers found that participants had "significantly higher" purchase intentions for hedonic (i.e. pleasurable) products when buying on touchscreens than on desktops, according to the study. On the flip side, participants had significantly higher purchase intentions for utilitarian (i.e. practical) products while using desktops instead of touchscreens. "The playful and fun nature of the touchscreen enhances consumers' favor of hedonic products; while the logical and functional nature of a desktop endorses the consumers' preference for utilitarian products," Zhu explains in a press release. The study also found that participants using touchscreen technology scored significantly higher on "experiential thinking" than subjects using desktop computers, whereas those with desktop computers demonstrated higher scores for rational thinking. “When you’re in an experiential thinking mode, [you crave] excitement, a different experience,” Zhu explained to Co. Design. “When you’re on the desktop, with all the work emails, that interface puts you into a rational thinking style. While you’re in a rational thinking style, when you assess a product, you’ll look for something with functionality and specific uses.” Zhu’s advice for consumers looking to conserve cash? Stow away the smartphone when you’re itching to splurge on a guilty pleasure. [h/t Fast Company]

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