Theanoとlasagneにを使ったニューラルネットワークの構成についてです

Theanoとlasagneを使ってニューラルネットワークを構築しているのですが、BatchNormを使うとエラーが出ます。

まず構築部分のコードは以下のようにしています。

Python
1from lasagne.layers import batch_norm
2
3l_in = lasagne.layers.InputLayer(
4        shape=(None, 1, input_height, input_width),
5    )
6
7    l_hid = lasagne.layers.DenseLayer(
8        l_in,
9        num_units=20,
10        # nonlinearity=lasagne.nonlinearities.tanh,
11        nonlinearity=lasagne.nonlinearities.rectify,
12        # W=lasagne.init.Normal(.0201),
13        W=lasagne.init.Normal(.01),
14        b=lasagne.init.Constant(0)
15    )
16
17    l_hid_b = batch_norm(l_hid)#これが無いと通る
18
19    l_out = lasagne.layers.DenseLayer(
20        l_hid_b,
21        num_units=output_length,
22        nonlinearity=lasagne.nonlinearities.softmax,
23        # W=lasagne.init.Normal(.0001),
24        W=lasagne.init.Normal(.01),
25        b=lasagne.init.Constant(0)
26    )
27

上記のbatch_normの部分を入れると以下のようなエラーが出ます。これは何が問題でしょうか？

Traceback (most recent call last):
File "launcher.py", line 167, in <module>
main()
File "launcher.py", line 146, in main
pg_su.launch(pa, pg_resume, render, repre='image', end='all_done')
File "/Users/tm/Google ドライブ/Python/DQN/deepDC4/pg_su.py", line 38, in launch
pg_learner = pg_network.PGLearner(pa)
File "/Users/tm/Google ドライブ/Python/DQN/deepDC4/pg_network.py", line 111, in init
grads = T.grad(loss, params)
File "/Users/tm/Library/Python/3.6/lib/python/site-packages/theano/gradient.py", line 589, in grad
handle_disconnected(elem)
File "/Users/tm/Library/Python/3.6/lib/python/site-packages/theano/gradient.py", line 576, in handle_disconnected
raise DisconnectedInputError(message)
theano.gradient.DisconnectedInputError:
Backtrace when that variable is created:

File "launcher.py", line 146, in main
pg_su.launch(pa, pg_resume, render, repre='image', end='all_done')
File "/Users/tm/Google ドライブ/Python/DQN/deepDC4/pg_su.py", line 38, in launch
pg_learner = pg_network.PGLearner(pa)
File "/Users/tm/Google ドライブ/Python/DQN/deepDC4/pg_network.py", line 81, in init
build_pg_network(pa.network_input_height, pa.network_input_width, pa.network_output_dim)
File "/Users/tm/Google ドライブ/Python/DQN/deepDC4/pg_network.py", line 373, in build_pg_network
l_hid_b = batch_norm(l_hid)
File "/usr/local/lib/python3.6/site-packages/lasagne/layers/normalization.py", line 372, in batch_norm
layer = BatchNormLayer(layer, name=bn_name, **kwargs)
File "/usr/local/lib/python3.6/site-packages/lasagne/layers/normalization.py", line 263, in init
batch_norm_stat=True)
File "/usr/local/lib/python3.6/site-packages/lasagne/layers/base.py", line 234, in add_param
param = utils.create_param(spec, shape, name)
File "/usr/local/lib/python3.6/site-packages/lasagne/utils.py", line 381, in create_param
spec = theano.shared(spec, broadcastable=bcast)