Dissertations, Theses, and Capstone Projects

Date of Degree

2-2025

Document Type

Thesis

Degree Name

M.S.

Program

Cognitive Neuroscience

Advisor

Kerstin Unger

Subject Categories

Cognitive Psychology

Keywords

Global, Working Memory, Binding, Selective

Abstract

Working memory (WM) is essential for numerous cognitive tasks, yet the mechanisms underlying selective access to specific subsets of its contents vs. global, nonselective access remain incompletely understood. Context-specific selection of individual items from WM has been found to be more time-consuming and error-prone than globally accessing all memory contents. This study investigates whether the performance costs of selective WM access arise primarily from demands on item-context binding memory. Previous research has suggested that only selective access relies on memory for item-context bindings whereas global access can solely rely on item memory. Across two experiments, we employed task paradigms that manipulated binding memory demands and selection requirements. Experiment 1 examined whether the need to form and retrieve item-context bindings underlies the cost of selective WM access compared to global access. Results revealed that selective WM access incurred higher error rates and slower reaction times (RT) than global access, particularly under conditions that required binding memory for item-context associations. However, accuracy and RTs indicated that the costs of selective WM retrieval cannot be entirely explained by the demands on binding memory. Experiment 2 aimed to disambiguate the findings from Experiment 1 by dissociating WM selection processes from probe recognition. Results showed that RTs for WM retrieval, when measured independently from the processing of a memory probe, were consistently slower for selective than global access, regardless of binding memory demands. Collectively, the present findings support the notion that selective and global WM access rely on distinct mechanisms. Specifically, the present results indicate that memory for item-context bindings is a key constraint on selective WM access, but not the sole constraint. Other factors contributing to the performance cost of selective access compared to global access may include the need to bias selection among competing representations, possibly requiring a greater activation gradient between relevant and irrelevant memory representations.

Download

Share

COinS