Tuesday, July 01, 2025

Brain stimulation can boost math learning in people with weaker neural connections

Frontoparietal network strength predicts certain math skills and whether brain stimulation can help

PLOS

Brain stimulation can boost math learning in people with weaker neural connections — image:
3D volume, generated manually by the authors in CONN, depicting the four frontoparietal seeds (left dlPFC, right dlPFC, left PPC, right PPC) as well as the right and left frontoparietal connectivity that was used in the functional connectivity analyses.
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Credit: Zacharopoulos G et al., 2025, PLOS Biology, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

The strength of certain neural connections can predict how well someone can learn math, and mild electrically stimulating these networks can boost learning, according to a study published on July 1st in the open-access journal PLOS Biology by Roi Cohen Kadosh from University of Surrey, United Kingdom, and colleagues.

When it comes to cognitive skills like reading and math, early advantages tend to compound over time. Mathematical abilities, however, seem to plateau from childhood to adulthood, raising the possibility that innate brain characteristics might shape academic outcomes independently of external factors like socioeconomic status. To better understand the neurobiology of mathematical learning, the authors measured connection strength between brain regions associated with learning math while 72 participants performed a 5-day math task. While solving math problems that required either calculating a solution or rote memorization, participants received weak electrical stimulation to either the dorsolateral prefrontal cortex (dlPFC), which plays an important role in executive function and calculations; the posterior parietal cortex (PPC), which is associated with memory recall; or a placebo. They also used magnetic resonance spectroscopy to measure two brain chemicals, glutamate and GABA, that hint at the brain’s current capacity for learning and change.

The researchers found that stronger baseline connectivity between dlPFC, PPC, and the hippocampus — a region involved in long-term memory and in this context, generalizing algorithms across problems — predicted better math performance when participants were asked to calculate the solution, but not when they memorized it. People with weaker connections between the dlPFC and PPC regions improved at calculation learning after electrically stimulating dlPFC. The authors suggest that these results hint at the viability of using brain stimulation to aid math learning in people struggling with biological disadvantages. The authors also identified a complex relationship between neurochemistry, brain plasticity, and communication between regions associated with executive function and memory. Future studies should more deeply examine these relationships, and test whether a neurostimulation approach like this could help people outside of the lab.

Professor Roi Cohen Kadosh, the lead author of the study and Head of the School of Psychology at the University of Surrey, said, “So far, most efforts to improve education have focused on changing the environment – training teachers, redesigning curricula – while largely overlooking the learner’s neurobiology. Yet, a growing body of research has shown that biological factors often explain educational outcomes in mathematics more powerfully than environmental ones. By integrating insights from psychology, neuroscience and education to develop innovative techniques that address these neurobiological constraints, we can help more people reach their potential, broaden access to diverse career pathways and reduce long-term inequalities in income, health and wellbeing.”

In your coverage, please use this URL to provide access to the freely available paper in PLOS Biology: http://plos.io/3STohc7

Citation: Zacharopoulos G, Dehghani M, Krause-Sorio B, Near J, Cohen Kadosh R (2025) Functional connectivity and GABAergic signaling modulate the enhancement effect of neurostimulation on mathematical learning. PLoS Biol 23(7): e3003200. https://doi.org/10.1371/journal.pbio.3003200

Author countries: United Kingdom, Canada, United States

Funding: Funding: This research was supported by the European Research Council (Learning&Achievement 338065 to RCK, https://erc.europa.eu/) and the Wellcome Trust (0883781 to RCK, https://wellcome.org/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Journal

PLOS Biology

DOI

10.1371/journal.pbio.3003200

Method of Research

Experimental study

Subject of Research

People

COI Statement

Competing interests: I have read the journal's policy and the author RCK of this manuscript has the following competing interests: RCK serves on the scientific advisory boards of Neuroelectrics Inc., Innosphere Inc., is the founder and shareholder of Cognite Neurotechnology Ltd., and is an Editorial Board Member at PLOS Biology.

Neurotechnology reverses biological disadvantage in maths learning

University of Surrey

Professor Roi Cohen Kadosh 1 — image:
Roi Cohen Kadosh
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Credit: University of Surrey

Safe, painless, and non-invasive brain stimulation could help people who are at risk of falling behind in maths, according to a new study led by the University of Surrey.

The study, published in PLoS Biology, found that applying safe electrical currents to the dorsolateral prefrontal cortex (dlPFC) – a region involved in learning and memory, focus, and problem-solving – helped people aged 18 to 30 solve maths problems more efficiently.

Seventy-two healthy adults took part in a five-day maths training programme – 24 received a form of brain stimulation known as transcranial random noise stimulation (tRNS) to the dlPFC, 24 received tRNS over the posterior parietal cortex and 24 received a placebo (sham) version of the treatment. This allowed researchers to compare the effects of tRNS in different brain regions against a placebo group.

The study showed, via brain scans, that individuals with stronger brain connectivity between the dlPFC and the posterior parietal cortex performed better in maths learning tasks. They then demonstrated that tRNS over the dlPFC significantly improved learning outcomes for individuals with lower natural brain connectivity between this region and the posterior parietal cortex – a neurobiological profile associated with poorer learning.

Improvements were also linked to lower levels of GABA – a brain chemical involved in learning. The same research team has previously shown that GABA plays a role in maths learning from childhood to adulthood, including A-level education.

Professor Roi Cohen Kadosh, the lead author of the study and Head of the School of Psychology at the University of Surrey, said:

“So far, most efforts to improve education have focused on changing the environment – training teachers, redesigning curricula – while largely overlooking the learner’s neurobiology. Yet, a growing body of research has shown that biological factors often explain educational outcomes in mathematics more powerfully than environmental ones. By integrating insights from psychology, neuroscience and education to develop innovative techniques that address these neurobiological constraints, we can help more people reach their potential, broaden access to diverse career pathways and reduce long-term inequalities in income, health and wellbeing.”

These findings point to a biological basis for the ‘Matthew effect’ – the tendency for those who start ahead in education to continue advancing, while others fall further behind. The study suggests that targeted brain stimulation could help bridge this gap.

As the UK looks to boost maths skills across the population, especially in young adults, this basic research and future research on larger samples outside the lab could help shape future policies by showing how tailored support, focusing on brain activity, might make learning fairer and more effective.

The study was funded by the European Research Council and the Wellcome Trust.

Journal

PLOS Biology

DOI

10.1371/journal.pbio.3003200

Article Title

Functional connectivity and GABAergic signaling modulate the enhancement effect of neurostimulation on mathematical learning

Article Publication Date

1-Jul-2025

Neurotechnology reverses biological disadvantage in maths learning

University of Surrey

Neurotechnology reverses biological disadvantage in maths learning

Safe, painless, and non-invasive brain stimulation could help people who are at risk of falling behind in maths, according to a new study led by the University of Surrey.

Professor Roi Cohen Kadosh, the lead author of the study and Head of the School of Psychology at the University of Surrey, said:

As the UK looks to boost maths skills across the population, especially in young adults, this basic research, and future research on larger samples outside the lab, could help shape future policies by showing how tailored support, focusing on brain activity, might make learning fairer and more effective.

The study was funded by the European Research Council and the Wellcome Trust.

[ENDS]

Roi Cohen Kadosh is available for interview, please contact mediarelations@surrey.ac.uk to arrange.

The preview of the paper is available at: https://plos.my.salesforce.com/sfc/p/#U0000000Ifis/a/PM000009bjx3/1ccrJNZ2kD0M4OhdrO1P8wnNttNKa796anHn.htxtoo

An image of Roi Cohen Kadosh is available here

Journal

PLOS Biology

DOI

10.1371/journal.pbio.3003200

Sugar, the hidden thermostat in plants

Researchers finally uncover how plants sense heat during the day

University of California - Riverside

UCR greenhouse — image:
Plants growing in a UC Riverside greenhouse.
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Credit: Elena Zhukova/UCR

For a decade, scientists have believed that plants sensed temperature mainly through specialized proteins, and mainly at night when the air is cool. New research suggests that during the day, another signal takes over. Sugar, produced in sunlight, helps plants detect heat and decide when to grow.

The study, led by Meng Chen, a University of California, Riverside professor of cell biology, shows that plants rely on multiple heat-sensing systems, and that sugar plays a central and previously unrecognized role in daytime temperature response. The findings, published in Nature Communications, reshape a long-standing view of how plants interact with their environment and could influence future strategies for climate-resilient agriculture.

“Our textbooks say that proteins like phytochrome B and early flowering 3 (ELF3) are the main thermosensors in plants,” Chen said. “But those models are based on nighttime data. We wanted to know what’s happening during the day, when light and temperature are both high because these are the conditions most plants actually experience.”

To investigate, the researchers used Arabidopsis, a small flowering plant favored in genetics labs. They exposed seedlings to a range of temperatures, from 12 to 27 degrees Celsius, under different light conditions, and tracked the elongation of their seedling stems, known as hypocotyls — a classic indicator of growth response to warmth.

They found that phytochrome B, a light-sensing protein, could only detect heat under low light. In bright conditions that mimic midday sunlight, its temperature-sensing function was effectively shut off. Yet, the plants still responded to heat, growing taller even when the thermosensing role of phytochrome B was greatly diminished. That, Chen said, pointed to the presence of other sensors.

One clue came from studies of a phytochrome B mutant lacking its thermosensing function. These mutant plants could respond to warmth only when grown in the light. When grown in the dark, without photosynthesis, they lacked chloroplasts and did not grow taller in response to warmth. But when researchers supplemented the growing medium with sugar, the temperature response returned.

“That’s when we realized sugar wasn’t just fueling growth,” Chen said. “It was acting like a signal, telling the plant that it’s warm.”

Further experiments showed that higher temperatures triggered the breakdown of starch stored in leaves, releasing sucrose. This sugar in turn stabilized a protein known as PIF4, a master regulator of growth. Without sucrose, PIF4 degraded quickly. With it, the protein accumulated but only became active when another sensor, ELF3, also responded to the heat by stepping aside.

“PIF4 needs two things,” Chen explained. “Sugar to stick around, and freedom from repression. Temperature helps provide both.”

The study reveals a nuanced, multi-layered system. During the day, when light is used as the energy source to fix carbon dioxide into sugar, plants also evolved a sugar-based mechanism to sense environmental changes. As temperatures rise, stored starch converts into sugar, which then enables key growth proteins to do their job.

The findings could have practical implications. As climate change drives temperature extremes, understanding how and when plants sense heat could help scientists breed crops that grow more predictably and more resiliently under stress.

“This changes how we think about thermosensing in plants,” Chen said. “It’s not just about proteins flipping on or off. It’s about energy, light, sugar, as well.”

The findings also underscore, once again, the quiet sophistication of the plant world. In the blur of photosynthesis and starch reserves, there’s a hidden intelligence. One that knows, sweetly and precisely, when it’s time to stretch toward the sky.

Journal

Nature Communications

DOI

10.1038/s41467-025-60498-7

Article Title

A multisensor high-temperature signaling framework for triggering daytime thermomorphogenesis in Arabidopsis

Article Publication Date

1-Jul-2025

Personality can explain why some CEOs earn higher salaries

WHAT MACHIAVELLIANISM MEANS TODAY

University of Arkansas

image:
Sam M. Walton College of Business professor of strategic management Jason Ridge.
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Credit: Whit Pruitt

The lucrative pay for American CEOs often makes headlines. In 1965, CEO compensation was 22 times higher than the pay of an average worker. In recent years, CEOs have been paid 344 times more than the people who work for them.

The personality of a CEO is one factor driving the increase in executive compensation, according to a new study from a team of researchers that includes Sam M. Walton College of Business strategic management professor Jason Ridge.

Leaders with a Machiavellian personality, someone who is self-interested, unemotional and manipulative, earn more than $1.5 million a year in additional pay. While the CEOs benefit, often the companies also come out ahead with Machiavellian leaders.

The paper “Chief Executive Officer (CEO) Machiavellianism and Executive Pay” was published in the Journal of Applied Psychology.

Past research on executive compensation has mainly focused on the organization’s structure, such as who sits on the compensation committee or how the board operates. Little research has been done on how a CEO’s personality affects their pay.

“The scarcity of research on such traits is notable given the extensive literature on CEO pay,” the authors write.

WHAT MACHIAVELLIANISM MEANS TODAY

In the early 16th century, the Italian diplomat and philosopher Niccolo Machiavelli wrote a political treatise called The Prince. The work made Machiavelli’s name synonymous with ruthlessness and amorality in the pursuit of a goal.

Today, psychologists use Machiavellianism, often shortened to “Mach,” as a term to describe people who are manipulative, unemotional, self-interested and see social interactions as contests to be won.

The researchers could not directly interview CEOs to determine if they had Machiavellian personalities.

“Executives are notoriously difficult to measure and do any research with. They’re busy people who are not going to fill out a survey or have time for an interview,” Ridge said.

The researchers created short video clips of CEOs, taken from speeches and media interviews. A panel of psychologists then watched the clips and scored the executives on their Machiavellian tendencies.

“There is research in psychology that suggests first impressions are particularly accurate for personalities that are more in the ‘dark triad,’” Ridge said.

The dark triad refers to non-pathological manifestations of Machiavellianism, narcissism and psychopathy.

The psychologists used a seven-point scale to measure the CEOs, who scored an average of 3.98 for Machiavellian tendencies. In other words, the executives showed higher Machiavellian personality traits than the general population but were not on the extreme end of the scale. For the study, the researchers classified any CEO with a score above 3.5 as Machiavellian.

SHOW ME THE MONEY

The researchers found that CEOs with Machiavellian personalities earned on average $1.64 million more per year than the mean pay for CEOs in the study, which was $12.9 million.

CEOs, unlike most other employees, negotiate their compensation directly with the board of directors.

“High Mach individuals typically want to win social interactions. They’re also more likely to engage in negotiations and the types of actions that would benefit them personally,” Ridge said.

For CEOs without Machiavellian personalities, their pay goes up when their company’s stock performs well. Machiavellian CEOs, however, manage to negotiate lucrative compensation even when their companies perform poorly.

The CEOs with Machiavellian tendencies also received larger severance packages, which are paid when executives are fired without cause.

While Machiavellian CEOs can be more expensive, they might also be worth the cost. The same negotiating skills and the desire to win that helps a Machiavellian CEO secure higher pay can also serve the company.

“When they’re negotiating with stakeholders, suppliers or buyers, they’re going to be better,” Ridge said.

The researchers also found that Machiavellian CEOs negotiate higher salaries for the other top executives at their companies.

A CEO typically earns more than other top executives at a company. Therefore, driving up their pay also benefits the CEO.

At the same time, higher pay for other top executives attracts and retains talent.

“Just like with any executive trait, with Machiavellianism there’s positives and negatives,” Ridge said. “We want to focus on the positives and figure out how we can minimize the negatives in the future.”

Journal

Applied Psychology

DOI

10.1037/apl0001290

Method of Research

Observational study

Subject of Research

People

Article Title

Chief executive officer (CEO) Machiavellianism and executive pay

This puzzle game shows kids how they’re smarter than AI

University of Washington

AI puzzlers-photo — image:
University of Washington researchers developed the game AI Puzzlers to show kids an area where AI systems still typically and blatantly fail: solving certain reasoning puzzles. In the game, users get a chance to solve puzzles by completing patterns of colored blocks. They can then ask various AI chatbots to solve and have the systems explain their solutions — which they nearly always fail. Here two children in the UW KidsTeam group test the game.
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Credit: University of Washington

ai_puzzlers_video [VIDEO]

While the current generation of artificial intelligence chatbots still flub basic facts, the systems answer with such confidence that they’re often more persuasive than humans.

Adults, even those such as lawyers with deep domain knowledge, still regularly fall for this. But spotting errors in text is especially difficult for children, since they often don’t have the contextual knowledge to sniff out falsehoods.

University of Washington researchers developed the game AI Puzzlers to show kids an area where AI systems still typically and blatantly fail: solving certain reasoning puzzles. In the game, users get a chance to solve ‘ARC’ puzzles (short for Abstraction and Reasoning Corpus) by completing patterns of colored blocks. They can then ask various AI chatbots to solve the puzzles and have the systems explain their solutions — which they nearly always fail to do accurately. The team tested the game with two groups of kids. They found the kids learned to think critically about AI responses and discovered ways to nudge the systems toward better answers.

Researchers presented their findings June 25 at the Interaction Design and Children 2025 conference in Reykjavik, Iceland.

“Kids naturally loved ARC puzzles and they’re not specific to any language or culture,” said lead author Aayushi Dangol, a UW doctoral student in human centered design and engineering. “Because the puzzles rely solely on visual pattern recognition, even kids that can’t read yet can play and learn. They get a lot of satisfaction in being able to solve the puzzles, and then in seeing AI — which they might consider super smart — fail at the puzzles that they thought were easy.”

ARC puzzles were developed in 2019 to be difficult for computers but easy for humans because they demand abstraction: being able to look at a few examples of a pattern, then apply it to a new example. Current cutting-edge AI models have improved at ARC puzzles, but they’ve not caught up with humans.

Researchers built AI Puzzlers with 12 ARC puzzles that kids can solve. They can then compare their solutions to those from various AI chatbots; users can pick the model from a drop-down menu. An “Ask AI to Explain” button generates a text explanation of its solution attempt. Even if the system gets the puzzle right, its explanation of how is frequently inaccurate. An “Assist Mode” lets kids try to guide the AI system to a correct solution.

“Initially, kids were giving really broad hints,” Dangol said. “Like, ‘Oh, this pattern is like a doughnut.’ An AI model might not understand that a kid means that there’s a hole in the middle, so then the kid needs to iterate. Maybe they say, ‘A white space surrounded by blue squares.’”

The researchers tested the system at the UW College of Engineering’s Discovery Days last year with over 100 kids from grades 3 to 8. They also led two sessions with the KidsTeam UW, a project that works with a group of kids to collaboratively design technologies. In these sessions, 21 children ages 6-11 played AI Puzzlers and worked with the researchers.

“The kids in KidsTeam are used to giving advice on how to make a piece of technology better,” said co-senior author Jason Yip, a UW associate professor in the Information School and KidsTeam director. “We hadn't really thought about adding the Assist Mode feature, but during these co-design sessions, we were talking with the kids about how we might help AI solve the puzzles and the idea came from that.”

Through the testing, the team found that kids were able to spot errors both in the puzzle solutions and in the text explanations from the AI models. They also recognize differences in how human brains think and how AI systems generate information. “This is the internet’s mind,” one kid said. “It’s trying to solve it based only on the internet, but the human brain is creative.”

The researchers also found that as kids worked in Assist Mode, they learned to use AI as a tool that needs guidance rather than as an answer machine.

“Kids are smart and capable,” said co-senior author Julie Kientz, a UW professor and chair in human centered design and engineering. “We need to give them opportunities to make up their own minds about what AI is and isn't, because they're actually really capable of recognizing it. And they can be bigger skeptics than adults.”

Runhua Zhao and Robert Wolfe, both doctoral students in the Information School, and Trushaa Ramanan, a master’s student in human centered design and engineering, are also co-authors on this paper. This research was funded by The National Science Foundation, the Institute of Education Sciences and the Jacobs Foundation’s CERES Network.

For more information, contact Dangol at adango@uw.edu, Yip at jcyip@uw.edu, and Kientz at jkientz@uw.edu.

DOI

10.1145/3713043.3728836

Article Title

"AI just keeps guessing": Using ARC Puzzles to Help Children Identify Reasoning Errors in Generative AI

Article Publication Date

News Release 1-Jul-2025

Study suggests remembrances of dead played role in rise of architecture in Andean region

Discovery places architecture in region 1,500 years earlier than previously thought

University of California - Davis

By Greg Watry, UC Davis

Archaeologists have long thought that monumental architecture — large, human-built structures that emphasize visibility — were products of societies with power structures, including social hierarchy, inequality and controlled labor forces. But this notion is being questioned as researchers uncover evidence that hunter-gatherer groups also built such structures.

In new research published June 24 in the journal Antiquity, University of California researchers report evidence of monumental structures built by hunter-gatherer groups at Kaillachuro, a collection of burial mounds located in the Titicaca Basin of the Peruvian Andes. The discovery places monumental architecture in the region 1,500 years earlier than previously thought, researchers said.

“Most researchers in the Andes argue that monumental architecture is a product of elites, intentionally constructed as a space of centralized power,” said the study’s corresponding author Luis Flores-Blanco, who conducted the research while a doctoral student in anthropology at UC Davis. “We propose that monumentality can emerge from hunter-gatherer groups without institutionalized inequality.”

The study — co-authored by Mark Aldenderfer, a professor emeritus of anthropology and heritage studies at UC Merced — suggests that ritual memory of the dead played a key role in the rise of monumental architecture in the region.

Burial activity began modestly, researchers said, with simple pits in the ground.

Over time, these practices evolved into the construction of stone masonry burial boxes that were eventually covered by mounds of debris resulting from ongoing rituals and remembrances of the community’s ancestors.

2,000 years of communal memorialization

The sites at Kaillachuro were built over a period of 2,000 years. Using radiocarbon dating, researchers suggest that these mounds are the earliest evidence of monumental architecture in the Titicaca Basin, with construction beginning about 5,300 calendar years before the present day. This is 1,500 years earlier than monumental architecture was thought to exist in the region.

“Kaillachuro is an extraordinary find because it shows that mounds were used in ritual contexts for over 2,000 years — though not necessarily continuously,” said Flores-Blanco, who is now a postdoctoral researcher at Arizona State University. “Our study shows that rituals surrounding the dead can, through repeated action, generate visible monumental formations in the landscape.”

Discovered in 1995 by Aldenderfer, Kaillachuro consists of nine low-lying mounds. Subsequent surveys and excavations of the mounds in the succeeding years uncovered human burials and stone tools, including projectile points, among other items.

The researchers theorize that Kaillachuro’s construction started when egalitarian hunter-gatherer groups began living in one place, allowing for population aggregation, low-level food production, expanded exchange networks and the development of bow-and-arrow technology.

“In this way, Kaillachuro was not initially planned as a mound site, but rather developed gradually through ongoing acts of burial ritual and remembrance tied to the community’s ancestors,” Flores-Blanco said.

An emphasis on remembrance of the dead

The study suggests an alternative pathway to mounded architecture that emphasizes community and ritual memory of the dead over societal power structures. In this instance, memory of the dead didn’t merely remain symbolic, but manifested as a materially visible architectural form.

“In many societies, the burial of ancestors compels us to return, reminisce and mark a space as special,” Flores-Blanco said. “At Kaillachuro, this happened in a similar way — though here, these repetitive practices formed mounds that not only shaped the landscape, but likely also influenced the practices of the living. This form of construction, rooted in communal memory, is what makes it monumental.”

The research was supported by the National Science Foundation, the H. John Heinz III Charitable Trust, the Rust Family Foundation, the American Philosophical Society, the Instituto Francés de Estudios Andinos - Carlos Brignardello Grant, and the National Geographic Society.

Journal

Antiquity

DOI

10.15184/aqy.2025.40

Method of Research

Experimental study

Subject of Research

People

Article Publication Date

24-Jun-2025