Misplacing your bearings in an unfamiliar setting may involve more than simply forgetting your location. A new study suggests that minor navigational challenges could serve as early indicators of Alzheimer’s disease, even before conventional memory assessments reveal any declines.
Researchers conducted tests involving approximately 100 older adults in a virtual reality experiment aimed at evaluating the brain’s innate sense of orientation.
The results indicate that individuals experiencing subjective cognitive decline (SCD)—a state where they sense their memory is deteriorating despite normal clinical evaluations—showed less directional awareness compared to their cognitively healthy counterparts.
“Individuals with SCD are recognized to be at a greater risk of progressing to dementia, which can ultimately develop into Alzheimer’s,” stated Professor Thomas Wolbers, one of the study’s authors.
During the experiment, participants aged between 55 and 89 donned VR headsets and traversed a barren digital landscape.
Their task was to follow floating balls along meandering paths and indicate their starting point. They then had to turn back to face the direction they were in at the beginning of the first pass.
While all participants performed within normal limits on traditional memory and cognitive tests, those with SCD consistently made significant errors in navigation tasks.
Participants followed a virtual reality ball to test their sense of orientation – Credit: Getty
“These navigational difficulties were not attributed to movement dynamics, such as an increased awareness of the ground while walking,” explained Dr. Vladislava Segen, the study’s lead author. “The misdirected orientation stemmed from cognitive factors, not movement-related issues.”
According to the researchers, the SCD group’s subpar performance might have been linked to “memory leaks,” as participants faced challenges in tracking past locations necessary for real-time navigation updates.
The team posits that this could be attributed to dysfunction in grid cells—specialized neurons responsible for constructing an individual’s mental coordinate system.
The researchers hope that this style of spatial testing may eventually enhance existing diagnostic tools for Alzheimer’s disease.
“In the long run, we foresee the potential for this method to be incorporated into clinical practices, particularly for the early diagnosis of Alzheimer’s,” Wolbers noted. “However, further testing and simplification of this technique are necessary first.”
For many of us, mushrooms are merely peculiar forest growths, and fungi might seem like something that belongs in a dish with cream. However, scientists are increasingly revealing that fungi are far more sophisticated than we once believed.
Some claim fungi are “intelligent,” hinting at a select group of researchers who might possess consciousness.
This theory has stirred up controversy among experts, yet the rest of us are curious whether our breakfast ingredients think about us. What should we take away from such findings?
For ages, biologists have debated animal consciousness in species like fish and bats. Now, even brainless entities like plants, slime molds, and fungi are entering the discussion.
There’s likely more to mushrooms than just their appearance. Cecelia Stokes, a doctoral researcher in bacteria at the University of Wisconsin-Madison, clarifies this.
Underneath the soil, mushrooms connect with thread-like filaments known as mycelium or “hyphae,” which extend through the earth to find food and companions. The visible mushrooms are merely the reproductive organs of the fungi.
“[Fungi have] Stokes stated:
While it remains uncertain if such behaviors signify intelligence, she suggests that, since this concept has been linked to non-living entities like artificial intelligence, it may be “worth considering” a broader interpretation of intelligence.
A New Perspective on Fungi
Fungi have gained recognition, with research suggesting that their mycelium forms a “Wood Wide Web,” connecting trees within forests through nutrient-seeking networks.
They’ve also gained popularity as harbingers of the Zombie Apocalypse in popular video games and HBO series like Our Last.
Recent studies indicate that fungi can perform actions usually associated with humans and other animals, such as learning, memory, and decision-making.
Fukusaki and his team from Tohoku University in Japan noted this behavior while “feeding” the wood-decomposing fungus, Fanerochetevertina, with wood blocks in the dirt.
In a 2020 study, Fukusaki and his colleagues observed that the fungi “decided” on certain wood blocks over others, even “remembering” their growth direction after being relocated.
According to Fukusaki, these actions reflect intellectual behavior. “Of course, it’s not the same system as a brain,” he clarifies, explaining that the fungi’s “remembering” likely involves growing more towards the area where food was first located.
“However, I believe you could argue this is a form of memory within the mycelium system—a sort of structural memory.”
Slime molds, too, display memory-like behaviors, navigating away from previously explored zones during their food searches.
Mycelium not only extends through the soil to locate food but also detects environmental changes – Photo Credit: Getty Images
Last year, Fukusaki’s team conducted another experiment to see if fungi could “recognize” shapes.
Using nine blocks arranged in either a cross or circle in the soil, they monitored the fungi’s growth from the center outward. In the cross formation, the fungi ultimately left the central block to reach the outer blocks.
Fukusaki notes that while this could be a natural response to depleting central resources, he still regards it as “very intelligent.” The fungi’s ability to distinguish between the center and edges implies they recognize spatial orientation.
In their published work, researchers label this behavior as a form of “pattern recognition,” commonly used in computing to identify specific data combinations, but also applicable to how individuals recognize faces and sounds.
In the case of the circle formation, the fungi vacated the center, indicating they “determined” that enough food was already available, sharing this information throughout their network.
Given these findings, Fukusaki believes we gain a broader understanding of intelligence by viewing it on a spectrum. “This way, we can discuss intelligence in a wider context and compare ourselves to different life forms,” he states.
“If we define intelligence solely by human standards, we cannot effectively discuss its evolution.”
read more:
Extending Our Understanding
Studies like Fukusaki’s inspire new ways to ponder fungal consciousness, such as the “Fungal Heart,” a concept introduced by fungal biologist Dr. Nicholas Money.
He presented the argument in an essay for Psyche magazine in 2021, suggesting that fungi could possess consciousness if we broaden our understanding of what consciousness entails.
In his paper, Money asserts that “this broadens the identification of different forms of consciousness across species, ranging from apes to amoebae.”
Other primitive mind theories consider the notion of a “liquid brain,” explaining how slime molds and various microbial consortia process information without traditional neurons.
Furthermore, electrical signals detected in fungi are likened to those found in animal neurons, leading some to question if fungi possess a brainless nervous system, a topic also raised in discussions about plants.
However, for Fukusaki, the consciousness of fungi is less critical. “For me, it’s insignificant whether fungi are conscious; what’s essential is that they exhibit intellectual behaviors and can solve their problems,” he explains.
Stokes, on the other hand, finds the concept of consciousness too malleable. She acknowledges that fungi could fit into the same category as humans and other animals and could seem more relatable, yet she asserts that science “hasn’t kept pace with the complexity of the findings.”
By drawing such comparisons, she warns, “we overlook many of the unique biological features that set them apart from us.”
Theory Versus Evidence
Humans have a tendency to draw parallels; thus, what about claims regarding a brainless nervous system? According to Stokes, it’s no surprise that fungi and plants can detect electrical signals.
“Every cell generates energy through the movement of ions across membranes,” she explains. Mobile ions (charged atoms or molecules) are crucial for how cells function to produce energy.
However, while it’s easy to dismiss the theories surrounding fungal intelligence and consciousness as eccentric, it’s important to explore what drives these ideas.
Often, the urge to humanize organisms that seem unfamiliar to us serves to make them more relatable. Attribute human characteristics to species can, at times, sway public sentiment towards their protection.
Nonetheless, when it comes to the Wood Wide Web, some scientists argue that the theory has been overstated. The belief that trees communicate through fungal networks is often stated as fact despite the thin evidence supporting it.
Similarly, defining fungi as conscious under current frameworks might be premature and could potentially hinder conservation efforts. Conversely, altering the definition opens up too broad an interpretation. But, why does that matter?
“You don’t need to attribute human traits to recognize how fascinating fungi are,” asserts Stokes, whose research specializes in toxic “deathcap” mushrooms.
About Our Experts
Cecelia Stokes is a doctoral researcher at the University of Wisconsin-Madison in the U.S., known for her contributions to scientific journals including New Botanist.
Fukusaki is an associate professor specializing in forest microbial ecology at Tohoku University in Japan. His research has been published in journals such as An Interdisciplinary Journal of Microbial Ecology, Fungal Ecology, and Forest Ecology and Management.
Getting someone, anyone, to notice what they've discovered is a problem for almost every scientist (and also a problem for almost anyone who discovers almost anything).
Mark Patterson and his colleagues at Northeastern University in Massachusetts tried a theatrical approach to raising awareness about marine microplastics. They found success by cosplaying at San Diego Comic-Con (“Mindful Engagement”). Patterson dressed up as a giant coral and wielded a sword-like “microplastic harvesting device,” while another member of the team dressed up as Amphitrite, the Greek sea goddess, “with bracelets and hair made from plastic debris.”
“The novelty of our costumes and accessories, not a traditional collection of cosplay characters, proved to be an appealing way to engage convention-goers,” they say. “Participants ranged from 1-9 people at a time, and engagements lasted from 1-8 minutes.”
The feedback makes people who think professionally about thinking wonder if anyone really thinks that the thinker knows much about thinking.
Thinkers who think about thinking go by many names, including cognitive scientists, brain scientists, neuroscientists, neuroeconomists, philosophers, neurophilosophers, psychologists, neuropsychologists, psychiatrists, neuropsychologists, therapists, neurotherapists, theologians, neurotheologists, and historians of ideas.
Never mind that they don't always praise each other, but call each other by various names.
Experts are debating consciousness: in the past five years alone, nearly 2,000 academic papers have been published exploring the question, “What is consciousness?”
And they ruminate about rumination. For example, Christopher Martin Kowalski, Donald Saklowski, and Julie Aitken-Sharmer of the University of Western Ontario in Canada wrote in May:What are you ruminating about? Development and validation of a content-dependent measure of rumination.“These three people who ruminate say they believe that existing measures of rumination assess ruminative thinking, regardless of the content of the rumination.”
What is the content of these ruminators' own ruminations? They give us glimpses of it in some of their other papers.
Perhaps you, too, will turn to the dictionary and ponder over gelotophobia, gelotophilia, and katagelasticism.
Explosive Insights
Questions arising from underground explosions, buried embalmed bodies, toxic groundwater (Feedback, July 20) and more continue to provoke people’s thinking.
William Drennan, a law professor at Southern Illinois University, takes a pessimistic view of embalming practices. writing Dickinson Law Review “Attempts to make coffins airtight and waterproof have led to a phenomenon known as 'Exploding Coffin Syndrome.' Essentially, attempts to make coffins airtight and waterproof lead to the disturbing conclusion that as the body decays, heat, gases and liquids build up inside the coffin, eventually causing an explosion.”
Apart from the intrinsic value of tradition, “there seems to be no benefit to embalming it after it has been made public,” Drennan said.
They conducted “numerous field tests and numerical simulations” [that] It is being implemented both domestically and internationally.”
While not specifically mentioning exploded, buried, and embalmed bodies, the team warns: “Calculating the parameters of the ground shock caused by an underground explosion is a complex energy-coupling problem.”
Telling all
There are two additions to the collection from Feedback titled “The Title Tells You Everything You Need to Know.”
If you've come across a similarly offensive, rancid, or blindingly obvious example, please send it (along with citation details) to Telltale titles, c/o Feedback.
Marc Abrahams is the founder of the Ig Nobel Prize ceremony and co-founder of the journal Annals of Improbable Research. He previously worked on unusual uses of computers. His website is Impossible.
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