Researchers hoped that they would learn how neurons drive consciousness by this year.Credit: Dr Torsten Wittmann/Science Photo Library
A 25-year science wager has come to an end. In 1998, neuroscientist Christof Koch bet philosopher David Chalmers that the mechanism by which the brain’s neurons produce consciousness would be discovered by 2023. Both scientists agreed publicly on 23 June, at the annual meeting of the Association for the Scientific Study of Consciousness (ASSC) in New York City, that it is still an ongoing quest — and declared Chalmers the winner.
What ultimately helped to settle the bet was a key study testing two leading hypotheses about the neural basis of consciousness, whose findings were unveiled at the conference.
“It was always a relatively good bet for me and a bold bet for Christof,” says Chalmers, who is now co-director of the Center for Mind, Brain and Consciousness at New York University. But he also says this isn’t the end of the story, and that an answer will come eventually: “There’s been a lot of progress in the field.”
The great wager
Consciousness is everything a person experiences — what they taste, hear, feel and more. It is what gives meaning and value to our lives, Chalmers says.
Can lab-grown brains become conscious?
Despite a vast effort — and a 25-year bet — researchers still don’t understand how our brains produce it, however. “It started off as a very big philosophical mystery,” Chalmers adds. “But over the years, it’s gradually been transmuting into, if not a ‘scientific’ mystery, at least one that we can get a partial grip on scientifically.”
Koch, a meritorious investigator at the Allen Institute for Brain Science in Seattle, Washington, began his search for the neural footprints of consciousness in the 1980s. Since then, he has been invested in identifying “the bits and pieces of the brain that are really essential — really necessary to ultimately generate a feeling of seeing or hearing or wanting,” as he puts it.
At the time Koch proposed the bet, certain technological advancements made him optimistic about solving the mystery sooner rather than later. Functional magnetic resonance imaging (fMRI), which measures small changes in blood flow that occur with brain activity, was taking laboratories by storm. And optogenetics — which allowed scientists to stimulate specific sets of neurons in the brains of animals such as nonhuman primates — had come on the scene. Koch was a young assistant professor at the California Institute of Technology in Pasadena at the time. “I was very taken by all these techniques,” he says. “I thought: 25 years from now? No problem.”
Adversarial collaboration
For many years, the bet was mostly forgotten. That is, until a few years ago, when it was resurfaced by Per Snaprud, a science journalist based in Stockholm who had interviewed Chalmers back in 1998. His recording of the chat reminded the pair of the terms they had set in the wager and the case of wine that was at stake.
Decoding the neuroscience of consciousness
Around that time, both Koch and Chalmers had become involved in a large project supported by the Templeton World Charity Foundation, based in Nassau, The Bahamas, aiming to accelerate research on consciousness.
The goal was to set up a series of ‘adversarial’ experiments to test various hypotheses of consciousness by getting rival researchers to collaborate on the studies’ design. “If their predictions didn’t come true, this would be a serious challenge for their theories,” Chalmers says.
The findings from one of the experiments — which involved several researchers, including Koch and Chalmers — were revealed on Friday at the ASSC meeting. It tested two of the leading hypotheses: Integrated information theory (IIT) and global network workspace theory (GNWT). IIT proposes that consciousness is a ‘structure’ in the brain formed by a specific type of neuronal connectivity that is active for as long as a certain experience, such as looking at an image, is occurring. This structure is thought to be found in the posterior cortex, at the back of the brain. On the other hand, GNWT suggests that consciousness arises when information is broadcast to areas of the brain through an interconnected network. The transmission, according to the theory, happens at the beginning and end of an experience and involves the prefrontal cortex, at the front of the brain.
Six independent laboratories conducted the adversarial experiment, following a pre-registered protocol and using various complementary methods to measure brain activity. The results — which haven’t yet been peer-reviewed — didn’t perfectly match either of the theories.
“This tells us that both theories need to be revised,” says Lucia Melloni, a neuroscientist at the Max Planck Institute for Empirical Aesthetics in Frankfurt, Germany, and one of the researchers involved. But “the extent of that revision is slightly different for each theory”.
Unfulfilled predictions
“With respect to IIT, what we observed is that, indeed, areas in the posterior cortex do contain information in a sustained manner,” Melloni says, adding that the finding seems to suggest that the ‘structure’ postulated by the theory is being observed. But the researchers didn’t find evidence of sustained synchronization between different areas of the brain, as had been predicted.
The human brain’s characteristic wrinkles help to drive how it works
In terms of GNWT, the researchers found that some aspects of consciousness, but not all of them, could be identified in the prefrontal cortex. Additionally, the experiments found evidence of the broadcasting postulated by advocates of the theory, but only at the beginning of an experience — not also at the end, as had been predicted.
So GNWT fared a bit worse than IIT during the experiment. “But that doesn’t mean that IIT is true and GNWT isn’t,” Melloni says. What it means is that proponents need to rethink the mechanisms they proposed in light of the new evidence.
Other experiments are underway. As part of the Templeton foundation initiative, Koch is involved in at study testing IIT and GNWT in the brains of animal models. And Chalmers is working on another project evaluating two other hypotheses of consciousness.
It’s rare to have proponents of competing theories come together at the table and be open to having their predictions tested by independent researchers, Melloni says. “That took a lot of courage and trust from them.” She thinks that projects like these are essential for the advancement of science.
As for the bet, Koch was reluctant to admit defeat but, the day before the ASSC session, he bought a case of fine Portuguese wine to honour his commitment. Would he consider another wager? “I’d double down,” he says. “Twenty-five years from now is realistic, because the techniques are getting better and, you know, I can’t wait much longer than 25 years, given my age.”
NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
