Visual working memory phenomena based on categorical tasks replicate using a continuous measure: A simple interpretation and some methodological considerations

Abstract

An increasingly popular method for investigating visuospatial working memory assumes stored features of objects such as color and orientation vary along continua subject to internal noise. It adapts the stimulus adjustment procedure from perceptual psychophysics to assess the precision with which stored features are represented in memory. This contrasts with methods using discrete, categorical measures of feature retention. The current study examined the replicability of some phenomena documented using conventional methodology when assessed using a continuous measure of feature recall. These concern memory for a short series of objects and include effects of recency, prioritizing an individual object, and presenting an irrelevant additional object after the last item (a poststimulus ‘suffix’). In two experiments we find broadly similar results using a continuous measure of color-orientation binding to those obtained previously using categorical measures, with small differences we regard as minor. We interpret the convergence between methods in terms of a simple analogy between categorical memory and categorical perception whereby categorical retrieval involves the application of a discrete criterion to an underlying continuum of stored feature information. We conclude by discussing some of the advantages and limitations of continuous and categorical measures of retention.

Does value-based prioritization at working memory enhance long-term memory?

“…A value effect was apparent in the WM task, with participants responding more accurately at SP1 when it was assigned with a higher value. This is in line with previous findings which have demonstrated an effect of probe value on WM performance (e.g., Atkinson et al, 2018Atkinson et al, , 2022Hitch et al, 2018;Hu et al, 2014Hu et al, , 2023. Here, we extend the effect to a recognition task using images of real-world objects.…”

“…In contrast, Another related question is whether the effect of value at WM on LTM differs depending on which serial position is more valuable. Within WM, the effect of value appears to be robust across SPs, with effects observed at the first position (e.g., Atkinson et al, 2018;Hu et al, 2014), but also at middle and final serial positions (Atkinson et al, 2021;Hu et al, 2014Hu et al, , 2023Hitch et al, 2018;Hu et al, 2023). However, effect durability may in part reflect initial position in the originally encoded sequence.…”

“…Other WM PRIORITIZATION -WM, LTM 21 studies have used longer exposure times, typically 500ms per item (e.g. Allen et al 2021;Atkinson et al, 2018;2019;Hu et al, 2023;Sandry et al, 2014;. Although value effects at WM appear to be unaffected by increased encoding time (Allen et al, 2021), it is possible that longer encoding times may result in more durable prioritization effects which are then more likely to persist into LTM.…”

“…a condition in which different items are more or less valuable; Allen & Ueno, 2018;Hu et al, 2014;. In other studies, high value items have been compared to a separate condition in which all items are equally valuable (Allen et al, 2021;Atkinson et al, 2018;2019;2022;Hu et al, 2023;Sandry et al, 2014). Value effects PRIORITIZATION -WM, LTM 4 are robust in working memory when participants are informed of the values in advance of encoding, with effects demonstrated using a variety of materials (e.g.…”

“…Atkinson et al, 2021;Hu et al, 2016;Johnson & Allen, 2023;Roe et al, under review;Sandry et al, 2014), retrieval methods (e.g. cued recall, recognition, color reproduction; Hu et al, 2016;Sandy et al, 2014;Atkinson et al, 2022;Hu et al, 2023), and age groups (e.g. Allen et al, 2021;Atkinson et al, 2019;Hu et al, 2016).…”