The idea of the interference theory of forgetting is that some learned material blocks the memory of other learned material. (Loftus, 1900.p.393)(Benjamin, Hopkins, & Nation, 1994. p.278)

This theory of interference works both ways:

• proactive interference/inhibition - already learned information hampers person's ability to remember new material (Loftus, 1900.p.393).
  1. encounter interfering material
  2. encounter material to be remembered
  3. memory test for material to be remembered
• retroactive interference/inhibition - learning new information hampers memory of older material (Loftus, 1900.p.393).
  1. encounter material to be remembered
  2. encounter interfering material
  3. memory test for material to be remembered