A new theory proposes how the brain’s long-range links build models of the world

The expanded theory assigns roles to connections among brain regions that help combine sensory information, movement and learned object models.

Editorial illustration — not from the study.

The Thousand Brains Theory holds that the neocortex is made of repeated computing units called cortical columns. Each column is proposed to learn models of objects by combining sensory information gathered across movements, while long-range connections help the columns reach agreement.

This extension addresses connections and theoretical problems left out of earlier versions. It argues that the neocortex works as a heterarchy—a network of interacting parts rather than a simple hierarchy—and proposes roles for pathways involving the thalamus and connections that carry information forward and backward. The authors also discuss how these pathways could support models made from smaller parts and convert information from the body’s viewpoint into a more general model of an object.

How brain links may work

The authors propose that the thalamus helps convert information about feature orientation and movement from an egocentric perspective—the viewpoint of the sensors—into an allocentric perspective used by learned models. They also propose that hierarchical feedforward and feedback connections, along with pathways linking the cortex through the thalamus, allow cortical columns to learn compositional models, in which larger objects or structures are built from smaller components.

The letter presents these proposed roles as an extension of the Thousand Brains Theory. It reviews how long-range connections are organized, relates the proposals to findings from anatomy, neurophysiology and behavior, and identifies predictions that could be tested in future experiments.

Why the theory matters

The extension offers a framework for explaining how many parts of the neocortex might combine information while learning structured models of objects. By assigning functions to long-range connections that earlier versions did not address, it aims to connect the theory more closely with known brain anatomy and behavior. The authors also discuss how the framework could influence the design of artificial intelligence systems, but the letter does not demonstrate that an AI system built this way performs better.

Evidence and open tests

This is a theoretical letter, not a report of a new experiment. Its claims draw on a review and interpretation of anatomical, neurophysiological and behavioral findings, and it proposes roles for different brain pathways along with predictions for future testing. The abstract does not report new data, performance measurements or experimental confirmation of the proposed mechanisms, so whether these roles accurately describe brain function remains an open question.

Twenty years of no-till farming improved Central Valley soil structure and water holding

A 20-year comparison in California’s Central Valley found that reduced tillage with cover crops produced more stable soil aggregates, greater water retention and different forms of carbon protection than standard tillage without cover crops. The conservation system also retained room for additional carbon storage, although the study measured potential rather than future gains.

47 minutes ago

Biology

Human brain organoids classified Braille letters with up to 83% accuracy

Human forebrain organoids classified artificial tactile Braille signals after a sensor converted the touch data into electrical stimulation. Accuracy averaged 61% with one organoid and rose to 83% when responses from three organoids were combined.

2 hours ago·1 views

Biology

A peptide reduced persistent traumatic memories in mice

A study in mice found that a peptide targeting the memory-related protein CPEB3 reduced the persistence of traumatic memories and anhedonia, a loss of pleasure. The findings are an early genetic preclinical test of a possible approach for PTSD, not evidence of a treatment in people.

7 hours ago·5 views