Undefined index: access in node_reference_node_reference_field_formatter_prepare_view()

I just migrated my site from Drupal 6 to Drupal 7 and it all seems to have been successful, except when I go to a node page, or the admin/content page, I'm getting a WSOD. I can find nodes through existing views, but when I click the link to the node, it's just the white screen. I checked the log messages and it looks like this is the error I'm getting:

> Notice: Undefined index: access in
> node_reference_field_formatter_prepare_view() (line 408 of
> /sites/all/modules/references/node_reference/node_reference.module).

Is anyone familiar with what might be causing this? The function on line 408 is this (the 4th line is 408)

>   foreach ($displays as $id => $display) {
>     if ($display['type'] != 'node_reference_nid') {
>       foreach ($items[$id] as $delta => $item) {
>         if ($item['access']) {
>           $items[$id][$delta]['node'] = $entities[$item['nid']];
>         }
>       }
>     }   }