Special Coverage on the 2020 Invited Talk

Forgetting Across a Hierarchy of Episodic Representations (149)

Aidan Horner and Nora Andermane (University of York)

Summary by Laura Mickes, Digital Content Editor

This recap is part of a special series of session summaries from the Psychonomic Society's 61st Annual Meeting. To read the rest of the series, click here.

Forget It All! (Or Maybe Just Some Of It)

Aidan Horner (@aidanhorner), one of the Psychonomic Society’s 2020 Early Career Award Recipients, talks about his research (with Nora Andermane and Bardur Joensen) on forgetting. 

Since Ebbinghaus’s work in the late 1800s and Dallenbach’s work in the early 1900s, forgetting research is focused on the rate of forgetting and why we forget. As a departure, Horner’s question focuses on whether forgetting occurs in an all-or-none fashion or in a fragmented way. 

To test this, participants memorize items together to form an event element in an episodic event. They then are later tested on those items. Over time, accuracy decreases because forgetting happens. Horner measures how the interrelated items are retrieved together by using a measure of dependency. If dependency decreases over time, then forgetting is fragmented. If it doesn’t, then forgetting happens holistically. 

As shown in the screenshot below, dependency occurs when direct associations are formed between the three items (whether encoded together or separately as long as the associations between each element is made). If the associations aren’t made, dependency does not occur.

And this dependency occurs in participants as young as four years, as shown in the figure below. This dependency does not occur for item-based representations, or the perceptual details, of an object.

Why is there some evidence for holistic forgetting and other evidence for fragmented forgetting? Horner proposes that different levels of representations, including the episodic events and item-based representations, map onto different regions in the brain in a hierarchical manner.

I look forward to hearing about the research to come on the topic. (And later forgetting parts or all of it!)