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Predictive pursuit emerges in high-dimensional recurrent neural networks

Tracking dynamic moving objects in the external world is ethologically important for many organisms. Recent experiments have examined neural dynamics supporting such behaviors by employing visually-guided pursuit in freely moving rodents, yet computational principles underlying this cognitive process are not well understood. To address this, we developed a recurrent neural network model for examining the predictive behaviors and computations that emerge during pursuit. We demonstrate that the model generates internal predictions of the targets future locations, with anticipatory behaviors increasing with exposure to stereotyped trajectories of the target. These internal predictions can be used by the model to pursue a target in a complex environment, and the RNNs emergent strategy is aligned with behavior when tested in rodents. In investigating the computations that underlie the RNNs ability to perform predictive pursuit, we found units sensitive to the position of the target relative to the artificial agent, a representation analogous to egocentric target neurons observed in animals performing pursuit tasks. Ablating these units significantly reduced model performance, establishing a causal role of this functional response type in efficient pursuit. Given the complexity of the task and agent behavior, we hypothesized that RNN models may use high-dimensional neural codes to support predictive pursuit. To test this, we trained models of varying rank and found that anticipatory behavior emerged only when the rank was sufficiently high, despite strong pursuit performance in lower rank models. All RNNs encoded the egocentric location of the target, whereas allocentric self and target locations emerged only in high-dimensional networks. Overall, our results suggest that, unlike commonly studied vision, motor, or memory tasks, predictive pursuit emerges in high-dimensional networks with sufficient resources.

The authors have declared no competing interest.

The Thermodynamics of Mind

To not only survive, but also thrive, the brain must efficiently orchestrate distributed computation across space and time. This requires hierarchical organisation facilitating fast information transfer and processing at the lowest possible metabolic cost. Quantifying brain hierarchy is difficult but can be estimated from the asymmetry of information flow. Thermodynamics has successfully characterised hierarchy in many other complex systems. Here, we propose the ‘Thermodynamics of Mind’ framework as a natural way to quantify hierarchical brain orchestration and its underlying mechanisms. This has already provided novel insights into the orchestration of hierarchy in brain states including movie watching, where the hierarchy of the brain is flatter than during rest. Overall, this framework holds great promise for revealing the orchestration of cognition.

Bizarre Hawking radiation may smooth the jagged hearts of black holes

It’s a longstanding pain point for physicists: Their theory of gravity, general relativity, predicts that a black hole must contain a singularity, a point where space and time are infinitely warped and the laws of physics break down.

Many researchers hope that a theory combining gravity and quantum mechanics—if it can ever be discovered—will someday remove the thorn. However, a full-fledged theory of quantum gravity may not be necessary, two theorists argue independently.

A pinch of quantum mechanics—in the form of an effect called Hawking radiation—may suffice, enabling a black hole to form, age, and evaporate without creating a singularity.


Hawking’s signature prediction may prevent vexing singularities from forming.

Gravitational waves may have created dark matter in the early universe

In the chaotic first moments after the Big Bang, ripples in spacetime may have done more than just echo through the cosmos—they could have helped create dark matter itself. New research suggests that faint, ancient gravitational waves might have transformed into particles that eventually became the invisible substance shaping galaxies today.

New Models Track Lava Flow on Earth and Other Planets

Scientists have used satellite data from the Mauna Loa eruption to improve lava flow modeling for both Earth and other planetary bodies. [ https://www.labroots.com/trending/earth-and-the-environment/…-planets-2](https://www.labroots.com/trending/earth-and-the-environment/…-planets-2)


Do lava flows behave the same on other planets as they do on Earth? This is what a recent study published in the Journal of Volcanology and Geothermal Research hopes to address as a team of scientists investigated new methods for predicting the lava flow behavior and how this could be applied to other planets. This study has the potential to help scientists and engineers develop novel scientific methods that can be applied both on Earth and beyond.

For the study, the researchers examined satellite data from the 2022 Mauna Loa eruption in Hawaii that lasted from November 27 to December 10. The motivation behind the study was to address a longstanding knowledge gap regarding the limitations of using individual satellite datasets for volcanic hazard response. To address this, the team analyzed satellite data from a combination of private companies and government agencies to gain insight into the entire time period of the eruption.

In the end, the researchers successfully identified an origin for the eruption along with gathering data and fresh insight on the lava flow behavior during the eruption and post-eruption activity. They note several times throughout the study that this new method could be used to study volcanic activity on Mars, Venus, and Jupiter’s volcanic moon Io, the last of which is the most volcanically active planetary body in the entire solar system that boasts hundreds of active volcanoes.

Raman Spectroscopy Could Reveal if Enceladus is Habitable

Raman spectroscopy can be used to identify minerals in Enceladus’s plumes to help determine if its subsurface ocean could support life. [ https://www.labroots.com/trending/space/30495/raman-spectros…abitable-2](https://www.labroots.com/trending/space/30495/raman-spectros…abitable-2)


Is Saturn’s ocean moon Enceladus habitable? This is what a recent study published in The Planetary Science Journal hopes to address as a team of scientists investigated the likelihood of Enceladus hosting the necessary ingredients for life as we know it. This study has the potential to help scientists develop new methods for finding life beyond Earth, even life as we don’t know it.

For the study, the researchers examined whether Raman spectroscopy, which is a common chemical analysis method in planetary science, could be used to analyze particles emitted from Enceladus’ plumes. These plumes, which originate from Enceladus’ south polar region, are responsible for discharging pieces of the moon’s interior ocean, including water vapor and other molecules. To accomplish this, the researchers used a vacuum chamber to simulate conditions on Enceladus and froze salt water at pH levels of 9 and 11. They then analyzed the salts using Raman spectroscopy to ascertain if it could identify particles within the water and determine which pH level they originated from.

In the end, the researchers discovered that the instrument could differentiate between the two pH levels while identifying sodium bicarbonate (baking soda) and sodium carbonate (washing soda) in both pH levels while identifying only sodium bicarbonate (baking soda) in pH 11. The researchers note these findings demonstrate the potential for using a spacecraft-mounted Raman spectrometer for future missions to Enceladus and other icy worlds with the goal of identifying the necessary ingredients for life as we know it.

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