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Despite the nursery rhyme about three blind mice, . Studying how mice see has helped researchers discover unprecedented details about how individual brain cells communicate and work together to create a mental picture of the visual world.

who studies how brain cells drive visual perception and how these processes can fail in conditions . “listens” to the electrical activity of neurons in the outermost part of the brain called the cerebral cortex, a . Injuries to the visual cortex can lead to blindness and other visual deficits, even when the eyes themselves are unhurt.

Understanding the activity of individual neurons – and how they work together while the brain is actively using and processing information – is a . Researchers have moved much closer to achieving this goal thanks to new technologies aimed at the mouse visual system. And these findings will help scientists better see how the visual systems of people work.

The Mind in the Blink of an Eye

Researchers long thought that vision in mice appeared . But it turns out visual cortex neurons in mice – just like – require and are particularly .

My colleagues and I and others have found that . This is surprising, because mouse eyes face outward rather than forward. Forward-facing eyes, like those of cats and primates, naturally have a larger area of focus straight ahead compared to outward-facing eyes.

This finding suggests that the specialization of the visual system to highlight the frontal visual field appears to be . For mice, a visual focus on what’s straight ahead may help them be more in front of them, helping them avoid looming predators or better .

Importantly, the center of view is in people. Since mice also rely heavily on this part of the visual field, they may be particularly useful models to study and treat visual impairment.

A Thousand Voices Drive Complicated Choices

Advances in technology have greatly accelerated scientific understanding of vision and the brain. Researchers can now routinely record the activity of thousands of neurons at the same time and pair this data with real-time video of a mouse’s face, pupil and body movements. This method can .

It’s like spending years listening to a grainy recording of a symphony with one featured soloist, but now you have a pristine recording where you can hear every single musician with a note-by-note readout of every single finger movement.

Using these improved methods, researchers like me are studying how specific types of neurons work together during complex visual behaviors. This involves analyzing how factors such as movement, alertness and the environment influence visual activity in the brain.

For example, my lab and I found that the speed of visual signaling is in the physical environment. If a mouse rests on a disc that permits running, visual signals travel to the cortex faster than if the mouse views the same images while resting in a stationary tube – even when the mouse is totally still in both conditions.

In order to connect electrical activity to visual perception, researchers also have to ask a mouse what it thinks it sees. How have we done this?

The last decade has seen researchers debunking long-standing . Like other rodents, mice are also and can learn how to “tell” researchers about the visual events they perceive through their behavior.

For example, mice can to indicate they have detected that a pattern has brightened or tilted. They can to move a visual stimulus to the center of a screen like a video game, and they can when they detect the visual scene has suddenly changed.

Mice can also use visual cues to to specific parts of the visual field. As a result, they can more quickly and accurately respond to visual stimuli that appear in those regions. For example, my team and I found that a faint visual image in the peripheral visual field is difficult for mice to detect. But once they do notice it – and tell us by licking a water spout – their subsequent responses are .

These improvements come at a cost: If the image unexpectedly appears in a different location, the mice are slower and less likely to respond to it. These findings resemble those found in studies on .

My lab has also found that – brain cells that prevent activity from spreading – strongly control the strength of visual signals. When we activated certain inhibitory neurons in the visual cortex of mice, we could effectively “erase” their perception of an image.

These kinds of experiments are also revealing that the boundaries between perception and action in the brain are . This means that visual neurons will respond differently to the same image in ways that depend on behavioral circumstances – for example, visual responses differ if the image will be , if it appears , or if it appears .

Understanding how different factors shape how cortical neurons rapidly respond to visual images will require advances in computational tools that can separate the contribution of these behavioral signals from the visual ones. Researchers also need technologies that can isolate how specific types of brain cells carry and communicate these signals.

Data Clouds Encircling the Globe

This surge of research on the mouse visual system has led to a significant increase in the amount of data that scientists can not only gather in a single experiment but also publicly share among each other.

Major national and international research centers focused on have been leading the charge in ushering in new optical, electrical and biological in action. Moreover, they make , inspiring . This collaboration accelerates the ability of researchers to analyze data, replicate findings and make new discoveries.

Technological advances in data collection and sharing can make the culture of scientific discovery more efficient and transparent – a major of neuroscience in the years ahead.

If the past 10 years are anything to go by, I believe such discoveries are just the tip of the iceberg, and the mighty and not-so-blind mouse will play a leading role in the continuing quest to understand the mysteries of the human brain.

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