Interference:
Forgetting because one memory blocks another, causing one or both memories to be distorted or forgotten.
Proactive Interference: PI
Forgetting occurs when older memories, already stored, disrupt the recall of newer memories memories. The degree of forgetting is greater when the memories are similar.
Retroactive Interference: RI
Forgetting occurs when newer memories disrupt the recall of older memories already stored. The degree of forgetting is again greater when the memories are similar.
Effects of Similarity: Procedure
John McGeoch and William McDonald (1931):
Studied retroactive interference by changing the amount of similarity between 2 sets of material. Learn a list of 10 words until they could remember them with 100% accuracy:
Group 1: synonyms- words with the same meanings as the originals.
Group 2: antonyms- words with the opposite meanings to the originals.
Group 3: words unrelated to the original ones.
Group 4: consonant syllables.
Group 5: 3 digit numbers.
Group 6: no new list- these participants just rested.
McGeoch and McDonald: Findings
E: Evidence from Lab Studies
Evaluation: Real Life Studies
E: Artificial Materials