Dons' boss Terry Brown told his club's website: "Coming out of West Ham you would expect Callum's distribution to be good and after watching him play I would also say that his aerial ability is one of his main strengths. I am sure he will do very well for us in his time here."
Northampton make their first trip to the home of the supporter-owned club on Tuesday night for a 7:45pm kick-off in League Two.
Prior to that it is a vital home fixture against Torquay United at Sixfields.
“If we can cut out a few of the little chances we’re giving away and create a few at the other end then that will benefit us,” boss Gary Johnson told the Chronicle & Echo. “We had some good chances at Southend and I don’t feel we’re really getting our just desserts at the moment.
“The boys need to go and do what they can do but at the same time stop the opposition from having as much of the ball and the chances they’re having, the games are far too 50-50 at the moment and we need to change that.”