Screensavers of the Brain: The Science of Dreaming

Screensavers of the Brain: The Science of Dreaming

Each night, you place your head on your pillow, close your eyes, and, barring insomnia, you lose consciousness of the world around you, drifting into blissful oblivion.  Eventually, you reawaken, only to hallucinate in a paralyzed body.  These hallucinations are called dreams.  Why do dreams happen, and what function do they serve?  Although these are simple questions, the purpose of dreaming (and to a large extent, sleep itself) is far from understood.Continue reading

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

Ghost in the Machine: The Neuroscience of Consciousness

Ghost in the Machine: The Neuroscience of Consciousness

Some questions cannot be addressed by science.  Like parallel universes, the consciousness of others is not something that can be directly observed, measured, or experienced.  Rene Descartes famously said,

I think, therefore I am.

a declaration that only knowledge of one’s own consciousness is absolute.  You assume that friends and neighbors have subjective, internal experiences similar to your own.  And yet, you will never know that these individuals are not mindless automatons, behaving in a manner similar to yourself yet lacking conscious experience.Continue reading

Surfing Brainwaves with EEG: A Classic Tool for Recording Temporal Brain Dynamics

Pictures are powerful tools for illustrating quantitative data and capturing public interest.  Each year, NASA releases many beautiful images of Martian dunes and distant nebulae which help win public funding.  Likewise, when it comes to grabbing headlines and commanding public attention, noninvasive studies of functional brain activity often do best when they beautifully illustrate said activity as colorful pixels dancing on the convoluted surface of the cerebral cortex.Continue reading