If you didn't put any cards into your graveyard when you manifested dread (perhaps because your opponent controls Leyline of the Void), Paranormal Analyst's ability will still trigger, but you won't be able to put any cards into your hand when it resolves. Similarly, if a card put into your graveyard when you manifested dread leaves your graveyard before Paranormal Analyst's ability resolves, you won't be able to put that card in your hand.