Item-specific encoding produces an additional benefit of directed forgetting: evidence from intrusion errors

Area of Science:

• Cognitive Psychology
• Memory Research

Background:

• List-method directed forgetting (LMDF) is a paradigm where participants encode two lists.
• Typically, LMDF impairs recall of the first list (List 1) and enhances recall of the second list (List 2).
• This effect is observed when participants freely choose their study strategies.

Purpose of the Study:

• To investigate the effect of enforced item-specific encoding on directed forgetting.
• To determine if directed forgetting enhances List 2 recall under controlled encoding conditions.
• To examine the impact of directed forgetting on cross-list intrusions.

Main Methods:

• A large-scale experiment was conducted using the list-method directed forgetting paradigm.
• Item-specific encoding instructions were enforced during the learning of both lists.
• Participants were divided into a forget group (told to forget List 1) and a control remember group.
• Recall for both lists and cross-list intrusions were measured.

Main Results:

• Enforced item-specific encoding impaired List 1 recall, consistent with prior findings.
• Directed forgetting did not enhance List 2 recall when encoding was item-specific.
• Crucially, directed forgetting significantly reduced cross-list intrusions, regardless of encoding type (incidental or intentional).

Conclusions:

• The enhancing effect of directed forgetting on List 2 recall is dependent on unconstrained study strategies.
• When encoding is item-specific, directed forgetting primarily functions to reduce memory interference.
• This suggests directed forgetting aids in memory differentiation and reduces intrusions from competing memories.