In Context #13 (Spring, 2005, pp. 19-23); copyright 2005 by The Nature Institute
Brain Activity and Conscious Experience
In 1780, Galvani simultaneously discovered electrical currents and laid the foundations of modern neurophysiology (Galvani 1791, p. 363). He found that frog muscles twitch when they come in contact with two different metals, and believed he had discovered the essence of life energy in electricity.
Since Galvani's day we have learned to use electrical technology to study brain function. We also construct robots, which are capable of sensing and recognizing their environment (as in voice recognition), and performing meaningful acts such as greeting guests or cleaning the kitchen (Figure 1). The question has arisen for many: is the human brain a sophisticated computer, and are we really robots? What would be the moral consequences for society if we thought of ourselves in this way?
Electricity and Physiology
If we connect a loudspeaker, a vo