Humans can smell 1 trillion scents

Smell always seems to get the short shrift of the sensory world. We don’t rely on it to navigate and communicate like we do sight and sound; it doesn’t send shivers up our spine like a soft caress; and no one’s ever claimed a whiff of roses to be “orgasmic” like they might a bite of chocolate peanut butter cheesecake.

But smell will be relegated to the sensory corner no longer! New research published in Science reveals that our olfactory abilities are far stronger than anyone had previously imagined, enabling us to detect more than 1 trillion different scents — 10 million times more than was originally thought.

I’ve got a full review of the article published on The Atlantic, including how the researchers arrived at this staggering number. So check it out, and don’t forget to stop and smell the roses; there may be more in there than you thought.

Read this mind-blowing article in less than 30 seconds!

Ok, maybe not literally 30 seconds. (Or mind-blowing, for that matter; mildly interesting, perhaps?)

By now we’ve all heard about the “insane new app” that allows you to read comfortably at speeds of 500 words per minute, roughly twice the standard reading pace. Topping out at 1000 words per minute, this, according to the experts at the Huffington Post, would compute to being able to get through a 300-page book like Harry Potter and the Sorcerer’s Stone in under 77 minutes, saving dozens of hours wasted delving through JK Rowling’s delightful prose. Just imagine how quickly you could get through a book of poetry this way!

The developers of this platform, Spritz, claim that the magic happens by projecting words one at a time in rapid-fire succession on the screen, a technique known as rapid serial visual presentation (RSVP), while also helpfully presenting them at their optimal recognition point (ORP), highlighting the letter most crucial for your brain to process the word. This then negates the time-consuming practice of eye saccades – moving your eyes across the screen as you read – searching for the ORP, typically located in the middle or slightly to the left of the word. Spritz combines ORP and RSVP so that words are not only presented at a blistering rate, not allowing you to internally vocalize Harry’s posh British accent, but also ensuring that they are located at the exact same – and optimal – position on the screen.

RSVP has been around for decades and has long been known to increase reading speeds. However, this technique has also come under criticism for impacting comprehension. One problem with RSVP is that it narrows your focus to only foveal vision, the content presented in the very center of your visual field. Unfortunately, the world (and the page) doesn’t just exist within these confines, meaning that parafoveal vision (the area outside of your direct focus) is neglected. However, a lot of important information is contained in those parafoveal regions, including cues about where to jump to next while reading. RSVP doesn’t allow for the preprocessing of this type of information, meaning you have no insight about what’s coming next in the text. Spritz claims that by placing words at their ORP the need for parafoveal preprocessing is negated because you automatically know where to focus for the next word. However, they don’t offer any solution to the loss of foreshadowing that is gleaned from preprocessing textual content.

Another concern over Spritz’s method is the absence of regressive saccades, the act of reading backwards. Again, reading backwards or re-reading information is undoubtedly time-consuming, but it can also be essential for fully comprehending a passage. What happens if you zone out while reading with Spritz? Better hope there wasn’t anything important that you missed, because there’s no going back, only onwards and upwards!

Dr. Benjamim Gagl, a cognitive psychologist at the University of Salzburg, explains that, far from being unnecessary time-consumers, these visual-cognitive processes are essential for adequate comprehension: “Although, these paradigms [RSVP and ORP] were very useful for various reasons, they are outdated and eye movement evidence suggests that parafoveal preprocessing, as well as regressive saccades, are central to normal fluent reading. Both parafoveal preprocessing and regressive saccades are not possible in a RSVP paradigm, which leads to differences in brain responses when compared to more natural reading paradigms.”

Despite these shortcomings, I have to confess, I was pretty impressed when I tried the beta mode on the company’s website – you can certainly discern what the passages are saying as they sprint across your screen, and it seemed to require less effort than deliberate skimming or other speed-reading methods. However, despite their claims of total comprehension, I did feel like something was lost in terms of processing and retaining content, not to mention the sheer pleasure that can be derived from reading. Previous studies of world-class speed-readers have shown that even among the best, adequate comprehension (roughly 75%) is lost at speeds of 600 words per minute. And any time you need to re-read a passage, in an abstruse piece of literature, say, or with an unfamiliar academic paper, Spritz seems like it would hurt more than it would help.

And then there’s the concern of fatigue. Somehow I doubt I’d be able to manage much more than 20 minutes using the device (I confess, I’m weak) before the words started blurring together and I lost my place – and my motivation. Admittedly though, screen fatigue happens even with conventional reading methods, so perhaps the gain in processing speed balances out the loss in total time spent doing it.

Clearly this app is not for everyone, nor for every purpose. Spritz certainly would have come in handy while I was prepping for my PhD oral defense, trying to skim through the hundreds of papers I’d read over the last three years. But when it comes to my Potter, I think I’ll stick with my internal narration. Expelliarmus!

Also posted on Mind Read.

The science behind the meat sweats

A  friend of mine asked that I write about an important medical condition that will likely afflict us all at one point in our lives (except perhaps vegetarians). A diagnosis involving discomfort, physiological distress, remorse, and possibly embarrassment. I am referring, of course, to the meat sweats.

Following a barbecue, particularly Korean or Argentinean in nature, or a rib-eating contest, one might find oneself feeling flushed, overcome by fatigue, and noticing a telltale dampness underneath the arms. As your body processes what it has just been forced to consume, you might begin to perspire profusely, purging liquid-protein through your pores.

While scientists posit that the meat sweats aren’t actually real, and indeed there are no academic papers dedicated to the topic, we carnivores know better.

There are a couple popular theories regarding the sweats, ranging from the high salt content in many cured meats – your body sweating more in an effort to expel the extra sodium – to the pure adrenaline experienced while eating another formerly living creature (apparently this is even greater if you hunt and kill the animal yourself).

Most likely though, the meat sweats are caused by the thermic effect of protein. While it may seem like every calorie you eat fixes itself permanently to your gut, the energy in food is conserved in several different ways. This includes fueling the process your body must go through to breakdown and digest what it is consuming. Remember the rumor that eating celery actually burns calories? This is purportedly because your body uses more energy to digest the fibrous vegetable than it contains (this is unfortunately not true, though you’re still unlikely to gain much weight on a diet of rabbit food).

As your body works to breakdown a meal, it begins to heat up, and just like any machine, the harder it works, the hotter it gets. Eating a lot of anything can cause this phenomenon, but a diet high in protein is particularly susceptible to turning you into a furnace. This is because protein has more than twice the thermic effect of fat or carbohydrates, with 15-35% of the energy consumed in a steak being required to digest it. This applies whether it’s chicken, hamburgers or tofu you’re chowing down on, though the soy sweats are a lesser-known phenomenon, probably because there aren’t many tofu-eating contests out there.

This thermic effect is one reason diets like Atkins and Paleo have taken off. However, before you dive face first into a plate of pulled pork, keep in mind that fat (the other main ingredient in bacon) has twice the energy density of protein at 9 calories per gram, but only burns off at a measly 5-10%.

So with barbecue season around the corner, try to control yourself and consume in moderation. But if this isn’t possible, prepare yourself a comfortable digestion spot on the couch, maybe with a towel underneath, and get ready to ride it out. At least you can be comforted that science is on your side.

Happy meating!

Spending more time in the dark could boost hearing in old age

Your brain can do amazing things, not least of which is change. Specifically, neurons can adapt and grow new connections to help compensate for a loss in function in other areas. This has been most dramatically shown in children who have an entire hemisphere of their brain removed, usually to treat extreme cases of epilepsy, the other side taking over so that they can still walk, talk and function normally. Another common example of this type of neural plasticity is the improvement of other senses, particularly hearing, after the loss of sight.

In my latest article for The Guardian, I review a study that reports improvements in hearing in mice that have been visually sensory deprived for a week — meaning they were locked in a darkened room. Amazingly, cells in a sensory relay-station part of the brain reorganized to strengthen their hearing after this temporary loss of sight, even in older mice, which were previously thought to be exempt from this ability. While it’s still early days, this finding opens up the possibility for less invasive ways to treat hearing loss in old age.

Check out the full piece here.