diff --git a/lib/models/vgg.py b/lib/models/vgg.py
index 6f82aaf..2fc2e8d 100644
--- a/lib/models/vgg.py
+++ b/lib/models/vgg.py
@@ -72,7 +72,7 @@ def feature_map_activations(self, x):
 
             # Disable cuDNN, else pooling indices will not be stored
             with chainer.using_config('use_cudnn', 'never'):
-                h = mp(h)
+                h = mp.apply((h,))[0]
             hs.append(h)
 
         return hs, pre_pooling_sizes