Interference theory

The interference theory is a theory of forgetting.

The interference theory refers to the sensation of one memory interfering with the retrieval of another memory. The interference theory comes into great relevance when the two memories – the one doing the interfering and the one being interfered with – are similar. There are two parts to the interference theory: proactive interference and retroactive interference.

Proactive interference

Proactive interference refers to a previously-encoded memory interfering with the retrieval of a more recently encoded memory. For example, a student who learned Spanish in primary school and French in secondary school (two similar ‘romance’ languages) may find themselves only being able to remember the Spanish word (and not the French word) for ‘red.’

In this case, the previously-encoded information of the Spanish word for ‘red’ is interfering with the memory of the French word for ‘red,’ which was encoded at a later date.

Younger siblings may be quite accustomed to proactive interference if their parents ever call them the name(s) of their older sibling(s).

Retroactive interference

Conversely, retroactive interference refers to newly-encoded memory interfering with the retrieval of a less recently encoded memory. For example, a Year 12 Psychology teacher may consistently call one of their ex-students by the name of a similar-looking student they are currently teaching.

In this case, the newly-encoded information of the name of the current student is interfering with the previously-encoded memory of the name of the old student.

Limitations of the interference theory

  • The interference theory is only relevant for declarative memories; it does not apply to procedural memories, which we appear to be capable of retaining regardless of interference
  • The methods used to test the theory may be artificial (i.e. conducted in a lab setting, which may skew the results)