The mind’s capability to interpret the visible world doesn’t rely solely on its superior outer layer, the cortex. A brand new examine in PLOS Biology reveals that an evolutionarily older mind area, the superior colliculus, accommodates neural networks able to finishing up elementary visible computations. These circuits allow the mind to separate objects from their backgrounds and establish which visible cues are most related in house.
Researchers discovered that this historical system, shared throughout all vertebrates, can independently produce center-surround interactions — a core visible course of that helps detect edges, distinction, and attention-grabbing particulars within the setting.
“For many years it was thought that these computations had been unique to the visible cortex, however we’ve proven that the superior colliculus, a a lot older construction in evolutionary phrases, may carry out them autonomously,” explains Andreas Kardamakis, head of the Neural Circuits in Imaginative and prescient for Motion Laboratory on the Institute for Neurosciences (IN), a joint heart of the Spanish Nationwide Analysis Council (CSIC) and the Miguel Hernández College (UMH) of Elche. “Which means the power to research what we see and determine what deserves our consideration just isn’t a current invention of the human mind, however a mechanism that appeared greater than half a billion years in the past.”
The Mind’s Historical “Radar” for What Issues
The superior colliculus works like a built-in radar, taking direct indicators from the retina earlier than the cortex receives them. It helps decide which components of the visible scene are most necessary. When one thing strikes, flashes, or instantly enters view, this construction reacts first, guiding the eyes towards the brand new stimulus.
To discover how this course of unfolds, the workforce mixed superior instruments comparable to patterned optogenetics, electrophysiology, and computational modeling. Through the use of gentle to activate particular retinal pathways and recording responses in mouse mind slices, they found that the superior colliculus can suppress a central visible sign when the encompassing space turns into energetic — a defining characteristic of center-surround processing. This impact was supported by cell-type-specific mapping and large-scale pc simulations.
“Now we have seen that the superior colliculus not solely transmits visible data but in addition processes and filters it actively, lowering the response to uniform stimuli and enhancing contrasts,” says Kuisong Music, co-first creator of the paper. “This demonstrates that the power to pick out or prioritize visible data is embedded within the oldest subcortical circuits of the mind.” These outcomes point out that the mechanisms directing consideration are deeply rooted in historical mind structure, lengthy earlier than the evolution of upper cortical areas.
Evolutionary Roots and Cognitive Significance
The findings problem the normal perception that advanced visible processing occurs solely within the cortex. As an alternative, they assist a hierarchical mannequin by which historical mind buildings deal with important computations essential for survival, comparable to detecting threats, following motion, or avoiding obstacles.
“Understanding how these ancestral buildings contribute to visible consideration additionally helps us perceive what occurs when these mechanisms fail,” Kardamakis notes. “Problems comparable to consideration deficit, sensory hypersensitivity, or some types of traumatic mind damage might partly originate from imbalances between cortical communication and these elementary circuits.”
The analysis workforce is now extending their work to reside animal fashions to review how the superior colliculus shapes consideration and controls distraction throughout goal-directed conduct. By understanding how visible distractions translate into actions, scientists hope to uncover the neurological foundation of consideration and its dysfunction in trendy life, the place visible overload is frequent.
An Worldwide Collaboration
This analysis represents a large-scale collaboration between the Karolinska Institutet, KTH Royal Institute of Expertise (Sweden), and the Massachusetts Institute of Expertise (MIT, USA). It additionally concerned Teresa FemenÃa, a researcher at IN CSIC-UMH, who performed a key position in creating the experimental work.
Constructing on these discoveries, Andreas Kardamakis and Giovanni Usseglio contributed a chapter to the brand new Evolution of Nervous Techniques sequence (Elsevier, 2025), edited by JH Kass. Their work broadens the evolutionary perspective, evaluating subcortical visible techniques throughout species. They present that buildings analogous to the superior colliculus — present in fish, amphibians, reptiles, birds, and mammals — share a standard goal: merging sensory and motor data to information gaze and a focus.
This historical mind group, conserved for over 500 million years, grew to become the muse upon which the cortex later advanced its increased cognitive features. “Evolution didn’t exchange these historical techniques; it constructed upon them,” Kardamakis explains. “We nonetheless depend on the identical fundamental {hardware} to determine the place to look and what to disregard.”
This work was supported by Spain’s State Analysis Company (Spanish Ministry of Science, Innovation and Universities), the Severo Ochoa Programme for Centres of Excellence, the Generalitat Valenciana by way of the CIDEGENT program, the Swedish Analysis Council, the Swedish Mind Basis, and the Olle Engkvist Basis.
