With the advent of the internet as a medium for performing business transactions, the need for a secure communication channel has never been more paramount. The study of behavioral biometrics - the verification and/or identification of individuals based on the way they provide information to an authentication system - originated from the need for a small footprint, versatile alternative to expensive hardware-based, or physiological, biometrics. As an emerging alternative to these traditional and more well-known physiological biometrics such as fingerprinting or iris scans, behavorial...

Spreading depression, a phenomenon characterized by changes in a wide range of neurophysiological processes, was described by Aristides Leao in 1944. The defining feature is a relatively enduring depression in the spontaneous activity of the brain, recorded using standard unipolar electrodes. Further, the reduction in spontaneous activity spreads from the site of initiation across the surface of the cortex. The phenomenon was discovered while Leao was investigating the response of the rabbit cortex, under dial narcosis, to faradic stimulation. This monograph describes in significant...