There is some debate as to whether responding to objects in our environment improves episodic memory or doesn't impact it. Some authors claim that actively encoding objects improves their representation in episodic memory. Conversely, episodic memory has also been shown to improve in passive conditions, suggesting that the action itself could interfere with the encoding process. This study looks at the impact of attention and action on episodic memory using a novel WWW task that includes information about object identity (What), spatial (Where) and temporal (When) properties. With this approach we studied the episodic memory of two types of object: Target, where attention or an action is defined, and Distractor, object to be ignored, following two selective states: active vs. passive selection. When targets were actively selected, we found no evidence of episodic memory enhancement compared to passive selection; but instead memory from irrelevant sources was suppressed. The pattern was replicated across a 2D static display and a more realistic 3D virtual environment. This selective attention effect on episodic memory was not observed on non-episodic measures, demonstrating a link between attention and the encoding of episodic experiences.
Keywords:What-Where-When task; episodic memory; recognition and cue recall; sensorymotor implication; inhibition.
2In our daily experience we often need to avoid responding to objects in an automatic manner in order to pursue a goal. When shopping for groceries, we may find ourselves actively avoiding the cream cakes in order to get the items on the fruit and vegetable list. In a pub, we may need to suppress grasping other glasses on the table to pick our own. In many cases, these situations occur without us being aware of it; but at other times they can become part of our autobiographical experience. While most would agree that selected objects can be stored in episodic memory, it is less clear what happens with the objects that we reject. The purpose of this research is to study how the active selection of a target among distractors is represented in episodic memory.The most common view is that objects which are the targets of goal-directed actions receive a boost in processing that enhances their representations in episodic memory (Engelkamp & Zimmer, 1994;Zimmer, et al, 2001). But there is little account of how distractors are represented. Here we present a set of three experiments to demonstrate that, contrary to the previous view, responding to an object does not influence target encoding but acts instead upon distractors, inhibiting them and preventing them from being represented in the episodic trace.
Measures of Episodic MemoryBefore we analyse how distractors can be affected by responses to the targets, we need to clarify a few theoretical points. The first problem that we encounter is the multiplicity of tasks used to measure episodic memory, and even the concept itself. Originally, Endel Tulving (1972) coined the term 'episodic memory' with reference to the ...