Final Decision? Why the Brain Keeps on Changing its Mind

Benjamin Franklin once quipped: ‘There are three things extremely hard: steel, a diamond, and to know oneself.’ Every decision we make, from pinpointing the source of a faint sound to choosing a new job, comes with a degree of confidence that we have made the right call. If confidence is sufficiently low, we might change our minds and reverse our decision. Now scientists are using these choice reversals to study the first inklings of self-knowledge. Changes of mind, it turns out, reflect a precisely tuned process for monitoring our stream of thoughts.Continue reading

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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Seeing Invisible Colors Knowing Neurons

Seeing Invisible Colors

What would the world be like without color?  Imagine you are a neurophysiologist, who studies color perception.  You know that light is a wave and that humans perceive color according to differential activation of color receptors, known as cones, in the retina.  You know that red cones are sensitive to long wavelengths, green cones are sensitive to medium wavelengths, and blue cones are sensitive to short wavelengths.  There’s just one issue: your entire life, you have been confined to a dark room where your only access to the outside world is a black and white television monitor.  You have never seen color.Continue reading