「額」 is read in this case as 「ひたい」, which means 'forehead'. The same character can also be read as 「がく」 but in that case it would mean 'picture frame'.
The kana is automatically generated using MeCab and (I think) the IPA dictionary. It isn't possible to manually correct them.
I see. Then in that case, I hope my comment will be useful as a reference for anyone who might study from this sentence. :)