diff --git a/nipype/interfaces/base/support.py b/nipype/interfaces/base/support.py
index 175438b6d5..14c8a55da1 100644
--- a/nipype/interfaces/base/support.py
+++ b/nipype/interfaces/base/support.py
@@ -87,7 +87,7 @@ def __exit__(self, exc_type, exc_value, exc_tb):
             timediff.days * 86400 + timediff.seconds + timediff.microseconds / 1e6
         )
         # Collect monitored data
-        for k, v in self._resmon.stop():
+        for k, v in self._resmon.stop().items():
             setattr(self._runtime, k, v)
 
         os.chdir(self._runtime.prevcwd)