When the blind can see again: A critical question of perception

Our sense of sight is arguably our most important sense.  Imagine how different your life would be if soon after birth, you lost the ability to see.  For over 1.4 million children worldwide, that is their life.  Being blind in developing countries like India has a costly impact: over 90% of blind children do not go to school, less than 50% make it to adulthood, and for those that do, only 20% are employed. But the real tragedy is that many of these cases of childhood blindness are completely avoidable and even treatable.

Why do they go untreated?

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Hubel and Wiesel & the Neural Basis of Visual Perception

Snap!  Crackle!  Pop!

Those are the sounds that Professors David Hubel and Torsten Wiesel heard in the early 1950s when they recorded from neurons in the visual cortex of a cat, as they moved a bright line across its retina.  During their recordings, they noticed a few interesting things: (1) the neurons fired only when the line was in a particular place on the retina, (2) the activity of these neurons changed depending on the orientation of the line, and (3) sometimes the neurons fired only when the line was moving in a particular direction.Continue reading

Understanding the Visual System: A Conversation with Botond Roska

Botond_RoskaWhen we see the world, there is a huge amount of processing that occurs in the neural circuits of the retina, thalamus, and cortex before we can even begin to comprehend our environment. And all of this computation happens very quickly! In this interview with Dr. Botond Roska, Senior Group Leader at the Friedrich Miescher Institute for Biomedical Research in Basel, Switzerland, we discuss his research on the elements of the visual system that compute visual information as well as how this knowledge can be used to help blind patients. Dr. Roska was inspired by the work and scientific approach of David Hubel (more about this on Wednesday!), and continues to follow his example: “Listen to the experiment, and not your colleagues,” says Dr. Roska. But what would he be, if not a neuroscientist? Find out in my conversation with Dr. Roska, who also shares his story of transition from musician, to medicine, to mathematics and to neuroscience!Continue reading