Are Addictions a Byproduct of Evolution?

iStock/Charles Wollertz
iStock/Charles Wollertz

Franklin Veaux:

Addictions are a byproduct of chemical warfare.

Plants evolved chemicals like caffeine, opioids, nicotine, cocaine, and theobromine because they are chemical poisons that protect the plant from being eaten by pests. They work by disrupting signaling in the brain, usually by binding to receptors for neurotransmitters in the brain.

They’re extremely potent neurotoxins that kill insects. A plant can’t run away from predators, so it uses chemical warfare instead: It secretes these chemicals that disrupt brain signaling, insects try to eat the plant, insects die.

Animals like humans are much bigger than insects. Doses of these chemicals that
disrupt an insect’s brain signaling to the point where insects die disrupt our brain signaling in ways that feel pleasant to us.

Many of these chemical poisons are effective at killing insects because they mimic natural neurotransmitters, but they are more effective than normal neurotransmitters. They grab hold of receptors and don't let go, or they persist longer than natural neurotransmitters—or both.

Your brain tries to maintain a normal baseline. If you take a chemical that disrupts brain signaling, it tries to work around the disruption to get things back to normal.

Let’s say you take a chemical that activates opioid receptors, like morphine. Your opioid signaling system starts sending out a flood of signals. You perceive this as pleasure.

Your brain says “hang on, the opioid signaling system is going crazy. I’m going to turn it down to get back to normal.” So it changes the number of opioid receptors.

You take the morphine again, and you don’t feel that incredible pleasure, because you have more opioid receptors in your brain for the morphine to activate. This is how tolerance works.

So you take more. Now you feel that rush of pleasure again.

But your brain says “Hang on, something still isn’t right. The opioid signaling system is still going bonkers. I better dial it down some more.” So it changes the number of receptors even further.

Now you stop taking the drug. Your brain has turned the opioid signaling system way way down, since you were blasting it with a chemical that sends it into hyperspace. Now you’ve stopped taking that chemical that was sending it into orbit, which means now it’s underactivated. You perceive that under-activation as intense pain. This is what withdrawal is.

This post originally appeared on Quora. Click here to view.

Presidents Day vs. President's Day vs. Presidents' Day: Which One Is It?

iStock
iStock

Happy Presidents’ Day! Or is it President’s Day? Or Presidents Day? What you call the national holiday depends on where you are, who you’re honoring, and how you think we’re celebrating.

Saying "President’s Day" implies that the day belongs to a singular president, such as George Washington or Abraham Lincoln, whose birthdays are the basis for the holiday. On the other hand, referring to it as "Presidents’ Day" means that the day belongs to all of the presidents—that it’s their day collectively. Finally, calling the day "Presidents Day"—plural with no apostrophe—would indicate that we’re honoring all POTUSes past and present (yes, even Andrew Johnson), but that no one president actually owns the day.

You would think that in the 140 years since "Washington’s Birthday" was declared a holiday in 1879, someone would have officially declared a way to spell the day. But in fact, even the White House itself hasn’t chosen a single variation for its style guide. They spelled it “President’s Day” here and “Presidents’ Day” here.


Wikimedia Commons // Public Domain

Maybe that indecision comes from the fact that Presidents Day isn’t even a federal holiday. The federal holiday is technically still called “Washington’s Birthday,” and states can choose to call it whatever they want. Some states, like Iowa, don’t officially acknowledge the day at all. And the location of the punctuation mark is a moot point when individual states choose to call it something else entirely, like “George Washington’s Birthday and Daisy Gatson Bates Day” in Arkansas, or “Birthdays of George Washington and Thomas Jefferson” in Alabama. (Alabama loves to split birthday celebrations, by the way; the third Monday in January celebrates both Martin Luther King Jr. and Robert E. Lee.)

You can look to official grammar sources to declare the right way, but even they don’t agree. The AP Stylebook prefers “Presidents Day,” while Chicago Style uses “Presidents’ Day.”

The bottom line: There’s no rhyme or reason to any of it. Go with what feels right. And even then, if you’re in one of those states that has chosen to spell it “President’s Day”—Washington, for example—and you use one of the grammar book stylings instead, you’re still technically wrong.

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Full vs. Queen Mattress: What's the Difference?

iStock.com/IPGGutenbergUKLtd
iStock.com/IPGGutenbergUKLtd

If you’re in the market for a new mattress this Presidents Day weekend (the holiday is traditionally a big one for mattress retailers), one of the first decisions you’ll need to make is regarding size. Most people know a king mattress offers the most real estate, but the difference between a full-sized mattress and a queen-sized one provokes more curiosity. Is it strictly a matter of width, or are depth and length factors? Is there a recommended amount of space for each slumbering occupant?

Fortunately, mattress manufacturers have made things easier by adhering to a common set of dimensions, which are sized as follows:

Crib: 27 inches wide by 52 inches long

Twin: 38 inches wide by 75 inches long

Full: 53 inches wide by 75 inches long

Queen: 60 inches wide by 80 inches long

King: 76 inches wide by 80 inches long

Depth can vary across styles. And while you can find some outliers—there’s a twin XL, which adds 5 inches to the length of a standard twin, or a California king, which subtracts 4 inches from the width and adds it to the length—the four adult sizes listed above are typically the most common, with the queen being the most popular. It's 7 inches wider than a full (sometimes called a “double”) mattress and 5 inches longer.

In the 1940s, consumers didn’t have as many options. Most people bought either a twin or full mattress. But in the 1950s, a post-war economy boost and a growing average height for Americans contributed to an increasing demand for larger bedding.

Still, outsized beds were a novelty and took some time to fully catch on. Today, bigger is usually better. If your bed is intended for a co-sleeping arrangement with a partner, chances are you’ll be looking at a queen. A full mattress leaves each occupant only 26.5 inches of width, which is actually slightly narrower than a crib mattress intended for babies and toddlers. A queen offers 30 inches, which is more generous but still well below the space provided by a person sleeping alone in a twin or full. For maximum couple comfort, you might want to consider a king, which is essentially like two twin beds being pushed together.

Your preference could be limited by the size of your bedroom—you might not be able to fit a nightstand on each side of a wider bed, for example—and whether you’ll have an issue getting a larger mattress up stairs and/or around tricky corners. Your purchase will also come down to a laundry list of options like material and firmness, but knowing which size you want helps narrow down your choices.

One lingering mystery remains: Why do we tend to shop for mattresses on Presidents Day weekend? One reason could be time. The three-day weekend is one of the first extended breaks since the December holidays, giving people an opportunity to trial different mattress types and deliberate with a partner. Shopping Saturday and Sunday allows people to sleep on it before making a decision.

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