Does LSD Induce Synesthesia?


Since Albert Hoffman discovered LSD (lysergic acid diethylamide) in 1938 and hippie culture made it a popular social drug in the 1960s, its psychedelic effects on the brain have been a source of scientific investigation. Anecdotally it’s known to cause visual and auditory hallucinations as well as reports of an individual’s sense of self dissolving and merging with a larger consciousness.

Recent research done at Imperial College London discovered through brain imaging that there is indeed a great deal of activity in the visual cortex of the brain when on LSD, and that it seems to interrupt connections between other brain networks, leading to that ephemeral state of oneness reported by users.

Yet these overlapping sensory experiences also share a lot in common with the brain condition synesthesia, in which an individual’s senses overlap or trigger each other in a way that is atypical. The disorder is rare. Estimates range, but most agree on approximately 1 percent of the population.

A group of researchers at the University of London (UoL) recently set out to study whether the effects of LSD qualified as true synesthesia. Their results, published in Neuropsychologia, suggest that what LSD-users are experiencing is not genuine synesthesia. The researchers say their findings open the door to a better understanding of how we process sensory perceptions.

“Synesthesia is basically understood as … a kind of condition in which a stimulant, known as an inducer, will consistently elicit a secondary experience that is atypical—not something generally experienced in the general population,” Devin Terhune, cognitive neuroscientist at UoL, tells mental_floss.

While every synesthete’s experience is unique, Terhune says there are some commonalities. For instance, many report seeing the letter B as blue, zero as white, and one as black. The most common instances of synesthesia are sound/color pairings (where the sound of a doorbell may evoke a green aura, for example) and color/grapheme pairings (where a particular letter or part of a word may appear in a specific color and even shape, like a blob or spiny edges).

To be considered congenital synesthesia, however, the response must be confirmed by consistency and specificity—that is, the same inducer must produce the same reaction every time.

For the placebo-controlled study, 10 physically and psychologically healthy participants were injected with saline solution for their first session, then they completed psychological tests to measure synesthesia-like experiences: a grapheme-color association test and a sound-color association test. After five to seven days, they were injected with 40-80 micrograms of LSD, and the tests were repeated.

While the participants said they had spontaneous synesthesia-like experiences while on LSD, they didn't report specific color experiences with graphemes and sounds, and sounds and colors were no more consistent on LSD than with the placebos. These results suggest that whatever is happening while under the influence of LSD, it isn't “true” synesthesia.

Given such anecdotal associations of color hallucinations in the existing literature about LSD, Terhune says he was surprised to find that “the color experiences effect was not even statistically significant.”

Terhune says the small sample size of 10 participants may have something to do with the weakness of the results. Another factor may have been the laboratory setting itself. Most people who take LSD aren't experiencing the drug's effects in a lab environment. “Factors like novelty and exposure to stimuli may be more critical,” he says. “Congenital synesthesia is really known as a stimulant-specific phenomenon—that something in your environment triggers your experience, reliably and automatically.”

He suggests future studies could be designed that would follow people taking LSD “out in the field” and ask them at various times, using an app, to report what they’ve been experiencing. This could yield a wider range of data.

Another question for future researchers is whether there is a “fundamental distinction between spontaneous forms of synesthesia and the inducer-specific experiences that congenital synesthetes’ experience,” Terhune says.

There may be genetic underpinnings to the disorder, which seems to be inherited in families. There are several working theories on its origins. One is the immune hypothesis, which considers that the genes responsible for normal cortical development are also involved in the development of synesthesia. The hyperconnectivity theory suggests that synesthetes, whose brains have been shown to have extra-developed myelin along sensory pathways, may experience a collaboration of senses resulting in synesthesia. Other theories consider the influence of the childhood environment or potentially higher levels of serotonin in the brains of synesthetes.

While the results of this study may not appear to have immediate implications—and no researcher is out to “cure” synesthesia—Terhune says that one motivation for his work is to understand the neurochemicals involved in the phenomenon. Plus, there is research to suggest that synesthetes with grapheme-color synesthesia have enhanced recognition memory compared to the average person, which could be of benefit to cognitive research.

“I don’t think synesthesia is going to reveal the really deep insights into different psychological phenomena,” Terhune concludes, “but it can provide us with some useful insights and potentially interesting models for things such as memory, imagery, and other cognitive functions.”

Penn Vet Working Dog Center
Stones, Bones, and Wrecks
New Program Trains Dogs to Sniff Out Art Smugglers
Penn Vet Working Dog Center
Penn Vet Working Dog Center

Soon, the dogs you see sniffing out contraband at airports may not be searching for drugs or smuggled Spanish ham. They might be looking for stolen treasures.

K-9 Artifact Finders, a new collaboration between New Hampshire-based cultural heritage law firm Red Arch and the University of Pennsylvania, is training dogs to root out stolen antiquities looted from archaeological sites and museums. The dogs would be stopping them at borders before the items can be sold elsewhere on the black market.

The illegal antiquities trade nets more than $3 billion per year around the world, and trafficking hits countries dealing with ongoing conflict, like Syria and Iraq today, particularly hard. By one estimate, around half a million artifacts were stolen from museums and archaeological sites throughout Iraq between 2003 and 2005 alone. (Famously, the craft-supply chain Hobby Lobby was fined $3 million in 2017 for buying thousands of ancient artifacts looted from Iraq.) In Syria, the Islamic State has been known to loot and sell ancient artifacts including statues, jewelry, and art to fund its operations.

But the problem spans across the world. Between 2007 and 2016, U.S. Customs and Border Control discovered more than 7800 cultural artifacts in the U.S. looted from 30 different countries.

A yellow Lab sniffs a metal cage designed to train dogs on scent detection.
Penn Vet Working Dog Center

K-9 Artifact Finders is the brainchild of Rick St. Hilaire, the executive director of Red Arch. His non-profit firm researches cultural heritage property law and preservation policy, including studying archaeological site looting and antiquities trafficking. Back in 2015, St. Hilaire was reading an article about a working dog trained to sniff out electronics that was able to find USB drives, SD cards, and other data storage devices. He wondered, if dogs could be trained to identify the scents of inorganic materials that make up electronics, could they be trained to sniff out ancient pottery?

To find out, St. Hilaire tells Mental Floss, he contacted the Penn Vet Working Dog Center, a research and training center for detection dogs. In December 2017, Red Arch, the Working Dog Center, and the Penn Museum (which is providing the artifacts to train the dogs) launched K-9 Artifact Finders, and in late January 2018, the five dogs selected for the project began their training, starting with learning the distinct smell of ancient pottery.

“Our theory is, it is a porous material that’s going to have a lot more odor than, say, a metal,” says Cindy Otto, the executive director of the Penn Vet Working Dog Center and the project’s principal investigator.

As you might imagine, museum curators may not be keen on exposing fragile ancient materials to four Labrador retrievers and a German shepherd, and the Working Dog Center didn’t want to take any risks with the Penn Museum’s priceless artifacts. So instead of letting the dogs have free rein to sniff the materials themselves, the project is using cotton balls. The researchers seal the artifacts (broken shards of Syrian pottery) in airtight bags with a cotton ball for 72 hours, then ask the dogs to find the cotton balls in the lab. They’re being trained to disregard the smell of the cotton ball itself, the smell of the bag it was stored in, and ideally, the smell of modern-day pottery, eventually being able to zero in on the smell that distinguishes ancient pottery specifically.

A dog looks out over the metal "pinhweel" training mechanism.
Penn Vet Working Dog Center

“The dogs are responding well,” Otto tells Mental Floss, explaining that the training program is at the stage of "exposing them to the odor and having them recognize it.”

The dogs involved in the project were chosen for their calm-but-curious demeanors and sensitive noses (one also works as a drug-detection dog when she’s not training on pottery). They had to be motivated enough to want to hunt down the cotton balls, but not aggressive or easily distracted.

Right now, the dogs train three days a week, and will continue to work on their pottery-detection skills for the first stage of the project, which the researchers expect will last for the next nine months. Depending on how the first phase of the training goes, the researchers hope to be able to then take the dogs out into the field to see if they can find the odor of ancient pottery in real-life situations, like in suitcases, rather than in a laboratory setting. Eventually, they also hope to train the dogs on other types of objects, and perhaps even pinpoint the chemical signatures that make artifacts smell distinct.

Pottery-sniffing dogs won’t be showing up at airport customs or on shipping docks soon, but one day, they could be as common as drug-sniffing canines. If dogs can detect low blood sugar or find a tiny USB drive hidden in a house, surely they can figure out if you’re smuggling a sculpture made thousands of years ago in your suitcase.

New Cancer-Fighting Nanobots Can Track Down Tumors and Cut Off Their Blood Supply

Scientists have developed a new way to cut off the blood flow to cancerous tumors, causing them to eventually shrivel up and die. As Business Insider reports, the new treatment uses a design inspired by origami to infiltrate crucial blood vessels while leaving the rest of the body unharmed.

A team of molecular chemists from Arizona State University and the Chinese Academy of Sciences describe their method in the journal Nature Biotechnology. First, they constructed robots that are 1000 times smaller than a human hair from strands of DNA. These tiny devices contain enzymes called thrombin that encourage blood clotting, and they're rolled up tightly enough to keep the substance contained.

Next, researchers injected the robots into the bloodstreams of mice and small pigs sick with different types of cancer. The DNA sought the tumor in the body while leaving healthy cells alone. The robot knew when it reached the tumor and responded by unfurling and releasing the thrombin into the blood vessel that fed it. A clot started to form, eventually blocking off the tumor's blood supply and causing the cancerous tissues to die.

The treatment has been tested on dozen of animals with breast, lung, skin, and ovarian cancers. In mice, the average life expectancy doubled, and in three of the skin cancer cases tumors regressed completely.

Researchers are optimistic about the therapy's effectiveness on cancers throughout the body. There's not much variation between the blood vessels that supply tumors, whether they're in an ovary in or a prostate. So if triggering a blood clot causes one type of tumor to waste away, the same method holds promise for other cancers.

But before the scientists think too far ahead, they'll need to test the treatments on human patients. Nanobots have been an appealing cancer-fighting option to researchers for years. If effective, the machines can target cancer at the microscopic level without causing harm to healthy cells. But if something goes wrong, the bots could end up attacking the wrong tissue and leave the patient worse off. Study co-author Hao Yan believes this latest method may be the one that gets it right. He said in a statement, "I think we are much closer to real, practical medical applications of the technology."

[h/t Business Insider]


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