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New study suggests we have 6,200 thoughts every day
fMRI scans show each new thing you think of as a "thought worm."
- The study passes on figuring out what we think, focusing instead on the frequency of thought.
- Consistent neurological signals identify the transitions between thoughts.
- fMRI scans tracked participants' thoughts while they watched movies and when they were at rest.
A new study from psychologists at Queen's University in Kingston, Ontario reports observations of the transition from one thought to another in fMRI brain scans. Though the researchers didn't detect the content of our thoughts, their method allowed them to count each one. Referred to as "thought worms," the team says that the average human has 6,200 thoughts per day.
"What we call 'thought worms' are adjacent points in a simplified representation of activity patterns in the brain," said senior study author Jordan Poppenk. "The brain occupies a different point in this 'state space' at every moment. When a person moves onto a new thought, they create a new thought worm that we can detect with our methods."
The study was recently published in the journal Nature Communications.
Billion Photos / Shutterstock
Not so much the 'what' as the 'when'
There's been a fair amount of research devoted to understanding what a person is thinking based on observations of brain activity. However, the only way to know what a particular pattern of brain activity means would be to recognize its similarity to a brain-activity template known to represent that type of thought. Few such templates are available thus far, and they're time-consuming and expensive to produce.
Poppenk and his MA student Julie Tseng went another way. "We had our breakthrough by giving up on trying to understand what a person is thinking about, and instead focusing on when they have moved on," said Poppenk. He adds, "Our methods help us detect when a person is thinking something new, without regard to what the new thought is. You could say that we've skipped over vocabulary in an effort to understand the punctuation of the language of the mind."
A thought, says the study, is generally viewed by researchers as a mental state, a "transient cognitive or emotional state of the organism." Poppenk says that since such states are relatively stable in terms of brain activity — sustained attention being most closely associated with the angular gyrus — it's possible to identify transitions between one state and another using fMRI data from individual participants. "We argue that neural meta-state transitions can serve as an implicit biological marker of new thoughts," the study reads.
The researchers verified their hypothesis using fMRI scans from two groups of participants: some who were watching movies, and others who were in a resting state. "Transitions detected by our methods predict narrative events, are similar across task and rest, and are correlated with activation of regions associated with spontaneous thought."
"Being able to measure the onset of new thoughts gives us a way," explains Poppenk, "to peek into the 'black box' of the resting mind — to explore the timing and pace of thoughts when a person is just daydreaming about dinner and otherwise keeping to themselves."
The use of fMRIs is key, he adds. "Thought transitions have been elusive throughout the history of research on thought, which has often relied on volunteers describing their own thoughts, a method that can be notoriously unreliable."
Spontaneous thought and attention regions distinguish transitions from meta-stability
Image source: Poppenk, et al
Have you thought your 6,200 thoughts yet today?
While we average 6,200 thought worms a day, Poppenk anticipates further research tracking the manner in which the number of daily thoughts an individual has may change over the course of a lifetime. Likewise, he's interested in investigating potential associations between how quickly a person jumps from one thought to another and other mental and personality traits. "For example," he says, "how does mentation rate — the rate at which thought transitions occur — relate to a person's ability to pay attention for a long period?"
In addition, the researcher wonders if "measures of thought dynamics serve a clinical function? For example, our methods could possibly support early detection of disordered thought in schizophrenia, or rapid thought in ADHD or mania."
"We think the methods offer a lot of potential," Poppenk says. "We hope to make heavy use of them in our upcoming work."
A new study finds that dogs fed fresh human-grade food don't need to eat—or do their business—as much.
- Most dogs eat a diet that's primarily kibble.
- When fed a fresh-food diet, however, they don't need to consume as much.
- Dogs on fresh-food diets have healthier gut biomes.
Four diets were tested<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTU5ODI1MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NjY0NjIxMn0._w0k-qFOC86AqmtPHJBK_i-9F5oVyVYsYtUrdvfUxWQ/img.jpg?width=980" id="1b1e4" class="rm-shortcode" data-rm-shortcode-id="87937436a81c700a8ab3b1d763354843" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="960" />
Credit: AntonioDiaz/Adobe Stock<p>The researchers tested refrigerated and fresh human-grade foods against kibble, the food most dogs live on. The <a href="https://frontierpets.com.au/blogs/news/how-kibble-or-dry-dog-food-is-made" target="_blank">ingredients</a> of kibble are mashed into a dough and then extruded, forced through a die of some kind into the desired shape — think a <a href="https://en.wikipedia.org/wiki/Food_extrusion" target="_blank">pasta maker</a>. The resulting pellets are sprayed with additional flavor and color.</p><p>For four weeks, researchers fed 12 beagles one of four diets:</p><ol><li>a extruded diet — Blue Buffalo Chicken and Brown Rice Recipe</li><li>a fresh refrigerated diet — Freshpet Roasted Meals Tender Chicken Recipe</li><li>a fresh diet — JustFoodforDogs Beef & Russet Potato Recipe</li><li>another fresh diet — JustFoodforDogs Chicken & White Rice Recipe.</li></ol><p>The two fresh diets contained minimally processed beef, chicken, broccoli, rice, carrots, and various food chunks in a canine casserole of sorts. </p><p>(One can't help but think how hard it would be to get finicky cats to test new diets. As if.)</p><p>Senior author <a href="https://ansc.illinois.edu/directory/ksswanso" target="_blank" rel="noopener noreferrer">Kelly S. Swanson</a> of U of I's Department of Animal Sciences and the Division of Nutritional Sciences, was a bit surprised at how much better dogs did on people food than even refrigerated dog chow. "Based on past research we've conducted I'm not surprised with the results when feeding human-grade compared to an extruded dry diet," he <a href="https://aces.illinois.edu/news/feed-fido-fresh-human-grade-dog-food-scoop-less-poop" target="_blank">says</a>, adding, "However, I did not expect to see how well the human-grade fresh food performed, even compared to a fresh commercial processed brand."</p>
Tracking the effect of each diet<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTU5ODI1OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3NjY1NTgyOX0.AdyMb8OEcjCD6iWYnXjToDmcnjfTSn-0-dfG96SIpUA/img.jpg?width=980" id="da892" class="rm-shortcode" data-rm-shortcode-id="880d952420679aeccd1eaf32b5339810" data-rm-shortcode-name="rebelmouse-image" data-width="1440" data-height="960" />
Credit: Patryk Kosmider/Adobe Stock<p>The researchers tracked the dogs' weights and analyzed the microbiota in their fecal matter.</p><p>It turned out that the dogs on kibble had to eat more to maintain their body weight. This resulted in their producing 1.5 to 2.9 times the amount of poop produced by dogs on the fresh diets.</p><p>Says Swanson, "This is consistent with a 2019 National Institute of Health study in humans that found people eating a fresh whole food diet consumed on average 500 less calories per day, and reported being more satisfied, than people eating a more processed diet."</p><p>Maybe even more interesting was the effect of fresh food on the gut biome. Though there remains much we don't yet know about microbiota, it was nonetheless the case that the microbial communities found in fresh-food poo was different.</p><p>"Because a healthy gut means a healthy mutt," says Swanson, "fecal microbial and metabolite profiles are important readouts of diet assessment. As we have shown in <a href="https://academic.oup.com/jas/article/92/9/3781/4702209#110855647" target="_blank">previous studies</a>, the fecal microbial communities of healthy dogs fed fresh diets were different than those fed kibble. These unique microbial profiles were likely due to differences in diet processing, ingredient source, and the concentration and type of dietary fibers, proteins, and fats that are known to influence what is digested by the dog and what reaches the colon for fermentation."</p>
How did kibble take over canine diets?<p>Historically, dogs ate scraps left over by humans. It has only been <a href="https://www.thefarmersdog.com/digest/the-history-of-commercial-pet-food-a-great-american-marketing-story/" target="_blank">since 1870</a>, with the arrival of the luxe Spratt's Meat Fibrine Dog Cakes—made from "the dried unsalted gelatinous parts of Prairie Beef", mmm—that commercial dog food began to take hold. Dog bone-shaped biscuits first appeared in 1907. Ken-L Ration dates from 1922. Kibble was first extruded in 1956. Pet food had become a great way to turn <a href="https://www.dogfoodadvisor.com/choosing-dog-food/animal-by-products/" target="_blank">human-food waste</a> into profit.</p><p>Commercial dog food became the norm for most household canines only after a massive marketing campaign led by a group of dog-food industry lobbyists called the Pet Food Institute in 1964. Over time, for most households, dog food was what dogs ate — what else? Human food? These days more than half of U.S. dogs are <a href="https://www.nytimes.com/2014/08/03/magazine/who-made-that-dog-biscuit.html" target="_blank">overweight or obese</a>, and certainly their diet is a factor.<span></span></p><p>We're not so special among animals after all. If something's healthy for us to eat—we're <em>not</em> looking at you, chocolate—maybe we should remember to share with our canine compatriots. Not from the table, though.</p>
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Eating veggies is good for you. Now we can stop debating how much we should eat.
- A massive new study confirms that five servings of fruit and veggies a day can lower the risk of death.
- The maximum benefit is found at two servings of fruit and three of veggies—anything more offers no extra benefit according to the researchers.
- Not all fruits and veggies are equal. Leafy greens are better for you than starchy corn and potatoes.