Helping or hacking? Engineers and ethicists must work together on brain-computer interface technology

In the 1995 film "Batman Forever," the Riddler used 3-D television to secretly access viewers' most personal thoughts in his hunt for Batman's true identity. By 2011, the metrics company Nielsen had acquired Neurofocus and had created a "consumer neuroscience" division that uses integrated conscious and unconscious data to track customer decision-making habits. What was once a nefarious scheme in a Hollywood blockbuster seems poised to become a reality. BCIs use brain signals to control objects in the outside world. They're a potentially world-changing innovation – imagine being paralyzed but able to "reach" for something with a prosthetic arm just by thinking about it.