Earlier studies hinted at such cells, but the tires and his colleagues systematically show that these are not rare eccentrics, but a clearly defined, functionally important subpopulation. “What we did not know is that these neurons control the completion of local patterns in the primary visual bark,” says Shin. “We have shown that these cells are causally involved in the process of completing the pattern, which, we believe, probably participates in the process of perceiving illusory contours,” adds adesnik.
Behavioral tests are still ahead
This does not mean that the mice “saw” illusory contours when neurons were artificially activated. “In this study, we did not actually measure behavior,” says adesnik. “It was about a neural view.” All that we can say at the moment is that IC codes can induce patterns of neural activity corresponding to those that show images during the normal perception of illusory contours.
“Perhaps the mice did not see them,” the tire admits, “because the methodology involves a relatively small number of neurons due to technical restrictions. But in the future it would be possible to expand the number of neurons, as well as introduce behavioral tests.”
This is the next line, says Adesnik: “We will photostimulate these neurons and see if we can generate the behavioral reaction of the animal even without any stimulus on the screen.” At the moment, the optogenetics can control only a small number of neurons, and the IC codes are relatively rare and scattered. “At the moment, we have stimulated only a small number of these detectors, mainly due to technical restrictions. IC codes are a rare population, probably distributed in layers.” [of the visual system]”, but we could imagine an experiment in which we recruit three, four, five, maybe even 10 times more neurons,” he says. “In this case, I think we will be able to start receiving behavioral reactions. We would definitely really like to conduct this test.”
Natural neurology, 2025. DOI: 10.1038/s41593-025-02055-5
Federica Sigorbissa is a scientific journalist; She writes about neurobiology and cognitive science for Italian and international publications.
