PALM Lab Perception, Attention, Learning and Memory Lab at the University of Adelaide

Research

Check out the PALM Lab’s publications below:

Highlighted

Object-based encoding constrains storage in visual working memory.
Object-based encoding constrains storage in visual working memory.
William X. Q. Ngiam, Krystian B. Loetscher, Edward Awh
Journal of Experimental Psychology: General   ·   11 Sep 2023   ·   doi:10.1037/xge0001479
Using a new ‘conjunction whole-report’ paradigm, we find that visual working memory is limited by object-based encoding, but that features can also be independently lost from the memory for an item. We developed a computational model that captures both feature-based and object-based effects.
Mapping visual working memory models to a theoretical framework
Mapping visual working memory models to a theoretical framework
William X. Q. Ngiam
Psychonomic Bulletin & Review   ·   28 Aug 2023   ·   doi:10.3758/s13423-023-02356-5
A review comparing and contrasting current theories and models of visual working memory, leading to a ‘theory map’. The hope is that the theory map provides a common space to better discuss various empirical phenomena and move towards a model-based approach to research visual working memory.
Distinguishing guesses from fuzzy memories: Further evidence for item limits in visual working memory
Distinguishing guesses from fuzzy memories: Further evidence for item limits in visual working memory
William X. Q. Ngiam, Joshua J. Foster, Kirsten C. S. Adam, Edward Awh
Attention, Perception, & Psychophysics   ·   20 Dec 2022   ·   doi:10.3758/s13414-022-02631-y
We developed a paradigm that leads to distinct patterns of responses produced by imprecise memories, and produced by guesses. We find clear evidence for guessing, in line with the notion of an item limit in visual working memory, but also suggest a resource-based model that can explain the observed results.

All

2023

Object-based encoding constrains storage in visual working memory.
Object-based encoding constrains storage in visual working memory.
William X. Q. Ngiam, Krystian B. Loetscher, Edward Awh
Journal of Experimental Psychology: General   ·   11 Sep 2023   ·   doi:10.1037/xge0001479
Using a new ‘conjunction whole-report’ paradigm, we find that visual working memory is limited by object-based encoding, but that features can also be independently lost from the memory for an item. We developed a computational model that captures both feature-based and object-based effects.
Mapping visual working memory models to a theoretical framework
Mapping visual working memory models to a theoretical framework
William X. Q. Ngiam
Psychonomic Bulletin & Review   ·   28 Aug 2023   ·   doi:10.3758/s13423-023-02356-5
A review comparing and contrasting current theories and models of visual working memory, leading to a ‘theory map’. The hope is that the theory map provides a common space to better discuss various empirical phenomena and move towards a model-based approach to research visual working memory.

2022

Distinguishing guesses from fuzzy memories: Further evidence for item limits in visual working memory
Distinguishing guesses from fuzzy memories: Further evidence for item limits in visual working memory
William X. Q. Ngiam, Joshua J. Foster, Kirsten C. S. Adam, Edward Awh
Attention, Perception, & Psychophysics   ·   20 Dec 2022   ·   doi:10.3758/s13414-022-02631-y
We developed a paradigm that leads to distinct patterns of responses produced by imprecise memories, and produced by guesses. We find clear evidence for guessing, in line with the notion of an item limit in visual working memory, but also suggest a resource-based model that can explain the observed results.

2021

Estimating the statistical power to detect set‐size effects in contralateral delay activity
Estimating the statistical power to detect set‐size effects in contralateral delay activity
William X. Q. Ngiam, Kirsten C. S. Adam, Colin Quirk, Edward K. Vogel, Edward Awh
Psychophysiology   ·   10 Feb 2021   ·   doi:10.1111/psyp.13791
A downsampling analysis of two large datasets measuring the contralateral delay activity (CDA), estimating the statistical power for detecting the presence of the CDA and its set-size effects. We provide an app that can estimate the statistical power for a given number of trials and subjects.

2019

Visual working memory for letters varies with familiarity but not complexity.
Visual working memory for letters varies with familiarity but not complexity.
William X. Q. Ngiam, Kimberley L. C. Khaw, Alex O. Holcombe, Patrick T. Goodbourn
Journal of Experimental Psychology: Learning, Memory, and Cognition   ·   01 Oct 2019   ·   doi:10.1037/XLM0000682
Visual working memory is better for familiar letters compared to unfamiliar characters, including artifical characters matched in stimulus complexity. This suggests learned experience can benefit the encoding of visual information.
“Memory compression” effects in visual working memory are contingent on explicit long-term memory.
“Memory compression” effects in visual working memory are contingent on explicit long-term memory.
William X. Q. Ngiam, James A. Brissenden, Edward Awh
Journal of Experimental Psychology: General   ·   01 Aug 2019   ·   doi:10.1037/xge0000649
When to-be-remembered displays contain statistical regularities, we can recall more items overall. However, this is contingent on subjects having explicit awareness of the regularities, supporting a long-term memory ‘chunking’ account.