diff --git a/mbmvpa/preprocessing/computational_modeling/peer_ocu.py b/mbmvpa/preprocessing/computational_modeling/peer_ocu.py
index b2e17e3..b5fa47d 100644
--- a/mbmvpa/preprocessing/computational_modeling/peer_ocu.py
+++ b/mbmvpa/preprocessing/computational_modeling/peer_ocu.py
@@ -27,20 +27,37 @@ def _set_latent_process(self, df_events, param_dict):
             U_safe  = p_gamble * pow(safe_Hpayoff, rho) + \
                 (1-p_gamble) * pow(safe_Lpayoff, rho)
             
-            self._add('EVsafe',U_safe)
-            
             U_risky = p_gamble * pow(risky_Hpayoff, rho) + \
                 (1-p_gamble) * pow(risky_Lpayoff, rho)
+            
+            self._add('Util_solo_safe',U_safe)
+            self._add('Util_solo_risky',U_risky)
+            
             if condition == 1: # safe-safe
                 U_safe += ocu
             elif condition == 3: # risky-risky
                 U_risky += ocu
-                
+                        
             pRisky = inv_logit(tau * (U_risky - U_safe))
-
-            self._add('OCUModifiedEVsafe',U_safe)
-            self._add('EVrisky',U_safe)
-            self._add('SUrisky',U_risky - U_safe)
+            
+            ##########################needs additional consideration for fMRI#######################
+            if choice == 0: # modified utility: U_OCU chosen gamble − U_OCU unchosen gamble, for fMRI extraction 
+                self._add('Util_unchosen_ocu',U_safe) # vmPFC
+                self._add('Util_unchosen_ocu',U_risky) 
+            elif choice == 1:
+                self._add('Util_chosen_ocu',U_safe) # vmPFC  
+                self._add('Util_chosen_ocu',U_risky)
+            # U_ocu_safe and U_ocu_risky should be merged into U_ocu
+                
+            if condition == 1: # safe-safe
+                self._add('distance',pRisky) # dACC, insula via interactive effect
+            elif condition == 3: # risky-risky
+                self._add('distance',1-pRisky) # dACC, insula via interactive effect
+            # two distance_ss and distance_rr are essentially the same parameter
+            #########################################################################################
+            
+            #self._add('Util_ocu_safe',U_safe)
+            #self._add('Util_ocu_risky',U_risky)
             self._add('Prisky',pRisky)
             self._add('Psafe', 1-pRisky)