p496fig13.20 (top image) A single avalanche sampling cell can learn an arbitrary space-time pattern by sampling it as a temporally ordered series of spatial patterns using a series of outstars.  Once an avalanche's sampling cell starts to fire, there is no way to stop it from performing the entire space-time pattern, no matter how dire the consequences.  (bottom image) If nonspecific arousal and a specific cue input are both needed to fire the next cell in an avalanche, then environmental feedback can shut off avalanche performance at any time, and volition can speed up or slow down performance.<BR>||  Space-time pattern learning: avalanche.  (top image) CS sampling signal-> serially activated outstars-> US spacetime input pattern. Sample a space-time pattern as a sequence of sptial patterns.  (bottom image) Nonspecific arousal as a command cell.  Polyvalent cell: nonspecific arousal as a STOP and a GO signal.