Will we ever communicate telepathically?
In a lab at Harvard Medical School, a man is using his mind to wag a ratâ€™s tail. To send his command, he merely glances at a strobe light flickering on a computer screen, and a set of electrodes stuck to his scalp detects the activity triggered in his brain. A computer processes and relays the electrodesâ€™ signal to an ultrasound machine poised over the ratâ€™s head. The machine delivers a train of low-energy ultrasound pulses into the ratâ€™s brain, stimulating its motor cortex â€“ the area that governs its movements. The pulses are aimed purposely at a rice-grain-sized area that controls the ratâ€™s tail. It starts to wag.