Lasers Trigger Phantom Shapes in Mouse Brains
Researchers at Seoul National University activated a small group of neurons in mice that made the animals' brains respond as if they saw shapes that were not there.
Updated on Nov. 9, 2026 in Alzheimer’s
Scientists used ultraprecise holographic lasers to activate a tiny cluster of cells in the first layer of image-sensing neurons in six mice, producing responses as if the animals were seeing phantom shapes, including a Kanizsa triangle. The findings were published in Nature Neuroscience.
Why it matters
The study tests whether activating specific brain cells alone can make the brain perceive something absent from the visual field. It builds on longstanding questions about how the brain fills in incomplete images.
The study used six mice and holographic lasers to target a small cluster of V1 neurons, and activation of these IC-encoder neurons recruited tens of thousands of additional neurons. Whether this mechanism applies to human vision is not established in the source.
The players
Hyeyoung Shin
Hyeyoung Shin is an assistant professor of neuroscience at Seoul National University who led the study on phantom visual perception.
The details
Researchers targeted a tiny cluster of cells in the brain's first layer of image-sensing neurons, called V1, using ultraprecise holographic lasers. The activated cells, named IC-encoder neurons, spread activity outward to recruit other neurons that complete a perceived image.
Timeline
2015: Dress debate over whether the garment was white-and-gold or blue-and-black, which the study references as a classic perception example.
More than 10 years later: Shin's study on perception was published in Nature Neuroscience.
Health Landscape
The study extends the public fascination with the 2015 dress debate into a mechanistic account of how perception can be shaped by neural activity. It adds a causal experimental approach to a question that has largely been studied through visual illusions in humans.
The study is at the mouse-research stage and does not yet change treatment options or daily health routines. Its value for patients depends on whether the neural mechanism it identifies proves relevant to human perception and cognitive conditions.
The takeaway
Activating a small set of neurons can shape what the brain perceives, showing that visual experience depends heavily on targeted neural activity. Whether the same process applies to human vision remains a question for future research.
Further reading
Explore more on the Alzheimer’s section for related research on brain function and cognition.
Source note: This article includes information reported by Popular Mechanics.
