Cannot update page; endless spinning arrow

Hi

Trying to edit this page:
http://lifespancognition.org/portfolio-item/people/

(just to add some photos)

Get the spinning arrow, never stops spinning, won’t let me
update anything when I click the Edit Portfolio Entry tab.

Used to work fine; AFAIK, I haven’t changed anything. I’ve
tried updating everything a few times, hasn’t helped.