Algorithm 1. The filtering process with the electrode E

N_ART ← ART; C ← C1; STOP ← 0; FIRST ← 0; BEFORE ← 0; i ← 1;   while STOP ← 0     N_ART ← N_ART - Projection (E, C, ART) //Filtering process     if variance(REF) > variance(N_ART) and R1      STOP ← 1 and ART ← N_ART      if BEFORE ← 1          ART ← OLD_ART      end     end     if R0      if FIRST← 0          OLD_ART ← N_ART      end      FIRST ← 1 and BEFORE ← 1     else      FIRST ← 0 and BEFORE ← 0     end     i ← i + 1; C ← Ci   end