ELECTRIC NOISE CAN INCREASE HUMAN TACTILE SENSATION of mechanical forces, new experiments have shown, opening possibilities for electric devices that can enhance sensitivity to touch in the elderly, stroke patients, and people with diabetes. Researchers in Massachusetts (contact Jim Collins or Kris Richardson, Boston University, 617-353-0390) applied a small mechanical force to the finger pads of 11 young, healthy subjects. The force was ordinarily too weak for the subjects to detect, with a magnitude of approximately 0.01 Newtons, roughly equivalent to pressing a pencil tip onto the finger very lightly. However, when the researchers applied this force along with 2 milliamps' worth of randomly fluctuating electrical current through the fingerpad, 9 of the 11 subjects then reported detecting the mechanical stimulus---without feeling the electric current. The researchers speculate that the electrical noise helped nerve cells in the finger pad to reach their threshold for firing a signal through the nervous system. Moreover, they observed that the 2 milliamps of electrical noise appeared to maximize the detectability of the stimulus--suggesting evidence for the phenomenon of "stochastic resonance" (Updates 121 and 293). Although a previous experiment provided evidence for stochastic resonance in tactile sensation of mechanical forces--by using random mechanical vibrations as the noise--this is the first human experiment in which the signal and noise were from different kinds of sources. (Richardson et al., Chaos, September 1998; this paper is available in PDF format--free PDF reader available at Adobe Acrobat web site.)