All Research

Behavioural improvements with thalamic stimulation after severe traumatic brain injury

NatureNature·
Read the paperDOI: 10.1038/nature06041

TL;DR

Imagine your brain is like a city, and consciousness is like the city's power grid. After a really bad brain injury, it's not that the buildings (brain regions) are all destroyed — some of them are still standing, just with the lights off because the power lines connecting them got damaged. The thalamus is like the city's central power relay station. In this study, scientists implanted tiny electrodes deep in the brain of a man who had been in a minimally conscious state — barely aware of the world — for 6 years after a car accident. By sending small electrical pulses to his thalamus, they essentially 'turned the lights back on' in parts of his brain that had gone dark. During periods when the stimulator was switched on, he could do things he couldn't do before: follow instructions, use his limbs more purposefully, and even eat food by mouth. When they switched it off, those abilities faded. It's like finding out that some 'broken' appliances in the city just needed the power reconnected.

Widespread loss of cerebral connectivity is assumed to underlie the failure of brain mechanisms that support communication and goal-directed behaviour following severe traumatic brain injury. Disorders of consciousness that persist for longer than 12 months after severe traumatic brain injury are generally considered to be immutable; no treatment has been shown to accelerate recovery or improve functional outcome in such cases. Recent studies have shown unexpected preservation of large-scale cerebral networks in patients in the minimally conscious state (MCS), a condition that is characterized by intermittent evidence of awareness of self or the environment. These findings indicate that there might be residual functional capacity in some patients that could be supported by therapeutic interventions. We hypothesize that further recovery in some patients in the MCS is limited by chronic underactivation of potentially recruitable large-scale networks. Here, in a 6-month double-blind alternating crossover study, we show that bilateral deep brain electrical stimulation (DBS) of the central thalamus modulates behavioural responsiveness in a patient who remained in MCS for 6 yr following traumatic brain injury before the intervention. The frequency of specific cognitively mediated behaviours (primary outcome measures) and functional limb control and oral feeding (secondary outcome measures) increased during periods in which DBS was on as compared with periods in which it was off. Logistic regression modelling shows a statistical linkage between the observed functional improvements and recent stimulation history. We interpret the DBS effects as compensating for a loss of arousal regulation that is normally controlled by the frontal lobe in the intact brain. These findings provide evidence that DBS can promote significant late functional recovery from severe traumatic brain injury. Our observations, years after the injury occurred, challenge the existing practice of early treatment discontinuation for patients with only inconsistent interactive behaviours and motivate further research to develop therapeutic interventions.

  • 1Bilateral deep brain stimulation (DBS) of the central thalamus modulated behavioural responsiveness in a patient who had remained in the minimally conscious state for 6 years following traumatic brain injury.
  • 2In a 6-month double-blind alternating crossover study, cognitively mediated behaviours increased during DBS-on periods compared to DBS-off periods.
  • 3Functional limb control and oral feeding (secondary outcome measures) also improved during active stimulation periods.
  • 4Logistic regression modelling demonstrated a statistical linkage between observed functional improvements and recent stimulation history.
  • 5The findings challenge the existing practice of early treatment discontinuation for patients with only inconsistent interactive behaviours after severe TBI.
Nature·

Over 20,000 precolonial earthworks in the Southwest Amazonia

Imagine flying a special laser scanner over the Amazon jungle that can 'see through' the treetops, like X-ray vision for the ground. When scientists did this, they found over 20,000 geometric shapes — ditches, mounds, and enclosures — built by ancient people long before Europeans arrived. These aren't small things: they're massive earthen structures, like monuments. This means the Amazon rainforest, which most people picture as empty wilderness, was actually home to millions of people who built cities and shaped the landscape. Think of it like discovering that a forest you thought was wild was actually someone's ancient garden on a continental scale.

Nature·

A digitally controlled silicon quantum processing unit

Imagine you want to build a super-powerful calculator that uses the weird rules of quantum physics to solve problems no regular computer can. The trouble is, the tiny quantum pieces — called qubits — are incredibly fragile and need to be kept colder than outer space. On top of that, you need wires and control signals going to every single qubit, and if you have thousands of them, the wiring becomes a nightmare. This team solved part of that puzzle by building their qubits out of silicon (the same stuff in your phone's chip), adding a tiny control computer that works at super-cold temperatures right next to the qubits, and using a special high-density cable to connect everything cleanly. They packed 54 tiny quantum dots onto a chip, arranged 18 of them into working qubits, and showed the qubits work about 10 times better than any previous silicon qubit of this type. They also ran basic error-correction experiments to prove the system is on track for real-world use.

Scientific American·

The 2026 World Cup's grass is an engineering problem

Imagine you're trying to play soccer in 16 different places across the United States, Canada, and Mexico — some in freezing cold, some blazing hot, some in stadiums with roofs that block sunlight. Half of those stadiums normally use fake grass. Now FIFA, the organization that runs the World Cup, wants every single pitch to feel and play exactly the same way, like a video game where every level has identical physics. To do that, they hired grass scientists — yes, that's a real job — who figured out how to grow special grass on thin mats with plastic underneath so it can be transported like a carpet, stitched with synthetic fibers so it doesn't rip when players sprint and tackle, and tested by literally shooting balls at it with a cannon to make sure it bounces right. Different grass species are used depending on whether a stadium is hot, cool, or dark. It's basically a giant, living, high-tech floor installation that has to survive the world's best athletes running on it.

Monthly Notices of the Royal Astronomical Society·

Remarks on the disproof of the unit distance conjecture

Imagine you scatter a bunch of dots on a piece of paper. The question is: how many pairs of those dots can be exactly 1 inch apart? The Erdős unit distance conjecture asked whether there's a specific mathematical formula that limits how often this can happen as you add more and more dots. Think of it like asking how many friendships can exist in a town where friends are defined as people who live exactly one mile apart — there's a suspected maximum, and Erdős guessed what that maximum should be. For decades, no one could prove or disprove his guess. Now, an AI apparently found a specific arrangement of dots (a 'counterexample') that breaks the expected limit, proving Erdős's conjecture was wrong. A team of elite mathematicians then checked and explained the AI's work in this paper.