Spatio-temporal adaptive penalized splines with application to   Neuroscience
  Data analysed here derive from experiments conducted to study neurons' activity in the visual cortex of behaving monkeys. We consider a spatio-temporal adaptive penalized spline (P-spline) approach for modelling the firing rate of visual neurons. To the best of our knowledge, this is the first attempt in the statistical literature for locally adaptive smoothing in three dimensions. Estimation is based on the Separation of Overlapping Penalties (SOP) algorithm, which provides the stability and speed we look for. 
Mar\'ia Xos\'e Rodr\'iguez-\'Alvarez and Mar\'ia Durb\'an and Dae-Jin   Lee and Paul H. C. Eilers
stat.ME