Parker played for Newcastle between 2005 and 2007, going on to make 55 appearances for the North East side.
And the England international midfielder says that he has seen Newcastle fans make the atmosphere at St. James’ Park so sour that it has become a difficult environment for their own team to play.
"They are the most passionate I have played for and, as good as they can be, they can also be a hindrance, I have been on both sides," he said.
"When you are there as an away team the first thing you are saying is 'let's keep them quiet' because the crowd will get on their case, on the other hand in the Newcastle dressing room they are saying 'we need to get the fans behind us'. So they could be a massive help for them at home."
Newcastle have always been backed by great numbers, but the frustration around the club is rising after years of failure.
The Magpies have been perennial strugglers in recent years, and this campaign has been particularly frustrating.
Despite a great amount of investment, Newcastle do not seem to have pushed on from last term, and they are currently sat in 18th place in the Premier League table.
Steve McClaren’s side lost their most recent fixture 5-1 against Chelsea, and only a serious improvement between now and the end of the season will see them move away from danger despite fans feeling they had turned a corner after a very impressive January transfer window.