diff --git a/dalle_pytorch/attention.py b/dalle_pytorch/attention.py
index 85a5c152..0a954748 100644
--- a/dalle_pytorch/attention.py
+++ b/dalle_pytorch/attention.py
@@ -1,4 +1,5 @@
 from inspect import isfunction
+from math import ceil
 
 import torch
 from torch import nn, einsum
@@ -287,6 +288,7 @@ def __init__(
         self,
         *args,
         block_size = 16,
+        text_seq_len = 256,
         num_random_blocks = None,
         **kwargs
     ):
@@ -301,6 +303,7 @@ def __init__(
                 num_heads = self.heads,
                 block = self.block_size,
                 num_random_blocks = num_random_blocks,
+                global_block_indices = list(range(ceil(text_seq_len / block_size))),
                 attention = 'unidirectional' if self.causal else 'bidirectional'
             ),
             max_seq_length = self.seq_len,
diff --git a/setup.py b/setup.py
index 7b40bf43..5338b856 100644
--- a/setup.py
+++ b/setup.py
@@ -4,7 +4,7 @@
   name = 'dalle-pytorch',
   packages = find_packages(),
   include_package_data = True,
-  version = '0.1.26',
+  version = '0.1.27',
   license='MIT',
   description = 'DALL-E - Pytorch',
   author = 'Phil Wang',