Explanations for forgetting:Interference

Many lab experiments have been carried out into interference, (e.g. McGeoch and McDonald's research on the effects of similarity).

Most of these studies show that both types of interference are very likely causes of forgetting from LTM.

Lab experiments control the effects of extraneous variables and so give us confidence that interefrence is a valid explanation.

The stimulus material used is often word lists. This is more realistic than consonant syllables, but is still quite different from things we remember in everyday life. 

For example in everyday life we remember people's faces, their birthdays, the ingredients of our favourite pizza, etc. 

The use of artificial materials makes intereference much more likely cause of 'everyday' forgetting. 

Baddeley and Hitch asked rugby players to recall the names of teams they had played so far in that season, week by week.

Accurate recall did not depend on how long ago the match took place. More important was the number of games played in the meantime. 

This study shows that interference explanations can apply to at least some everyday situations. 

Time periods between learning lists of words and recalling them are quite short in lab stuudies. A participant might learn two lists within 20 minustes.

Research reduces the whole experience of learning into a short time period which does not reflect how we learn and remember most information in real life. 

So the conclusions generated from research into forgetting in LTM may not generalise outside the lab. The role of intereference may be exaggerated. 

Tulving and Psotka gave participants five lists of 24 words, each organsied into six categories (e.g.metals, fruits, etc.). Categories were not explicit but it was assumed they would be obvious when presented.

Recall was about 70% for the first list, but this fell as each additional list was learned, presumably due to interference. However, when given a cued recall test (told the names of the categories) recall rose again to about 70%. 

The memories of the words were stored in LTM but inteference prevented access to them. When given a cue, it was easier to access the forgotten words.