Interference

What is the interference hypothesis

Interference from other items causes recall errors

What are the 2 types of interference

Proactive and retroactive

What is proactive interference

Where information stored previously makes it harder to add new information

Proactive interference is interference from ___ onto ____

Old onto new

What is retroactive interference

Where new information coming in overwrites older information in memory

Retroactive interference is interference from ___ onto ____

New onto old

How can you test for proactive interference

Have subjects (S) repeat back short lists of related items that are said by the experimenter (E)

What would an example with 3 lists look like

List 1:

E: chair, soda, rug, painting

S: chair, sofa, rug, painting

List 2:

E: lamp, dresser, desk, bed

S: lamp, dresser, desk, PAINTING

List 3:

E: bookcase, stool, bench, table

S: bookcase, LAMP, SOFA, table

What does the example that tests for proactive interference show

After list 1, we begin to see errors where people erroneously (incorrectly) recall items from earlier lists. Old items are still in memory and are spontaneously recalled, and people can’t keep track of which items belong to which list

How does proactive interference build up

It builds up as similar information must be learned

How does performance improve for proactive interference

When the type of information changes

What does proactive interference suggest

It suggests the value of rotating material across a learning session

How can you test for retroactive interference

Give subjects a set of letters to remember and then have them either count backwards or say the alphabet backwards

What would an example look like for both counting backwards and saying the alphabet backwards

Example 1:

Remember Q W H N

Count backwards from 20

Now recall the set of letters asked to remember

Example 2:

Remember Q W H N

Say the alphabet backwards

Now recall the set of letters asked to remember

What are the results for the test for retroactive interference

Recall is higher after counting than after reciting the alphabet

What can we conclude from these results

New letters seem to interfere more with prior letter memory

Is decay the only way information is lost

No, information can be lost from interference from old information onto new (proactive interference) and from new information onto old (retroactive interference)