Bound feature combinations in visual short-term memory are fragile but influence long-term learning

Abstract

We explored whether individual features and bindings between those features in VSTM tasks are completely lost from trial to trial or whether residual memory traces for these features and bindings are retained in long-term memory. Memory for arrays of colored shapes was assessed using change detection or cued recall. Across trials, either the same color-shape (integrated object) combinations were repeated or one feature was repeated while the other varied. Observers became sensitive to the repetition of bindings, but only if it occurred on every trial. Repetition of single features only led to learning in the cued-recall task, and was weak compared to whole-object repetitions. Results suggest that representations in visual short-term memory comprise integrated objects rather than individual features. These representations are readily displaced by new representations formed on subsequent trials. However, when a given representation is not displaced, longerterm residual traces can be generated to support long-term learning, and any learning that does occur is based on integrated objects, not individual features.

Retiring the Central Executive

“…After a blank interval, a second array is shown, but with changes in one of the colours, or one of the shapes, or with two of the shapes swapping colours (e.g. Allen, Baddeley & Hitch, 2006;Colzato, Raffone & Hommel, 2006;Logie, Brockmole & Vandenbroucke, 2009;Treisman, 2006). A range of studies has demonstrated that this kind of task is insensitive to cognitive changes in healthy ageing (Brockmole & Logie, 2013;Brockmole, Parra, Della Sala & Logie, 2008;Brown & Brockmole, 2010;Isella, Molteni, Mapelli, and Ferrarese, 2015;Rhodes, Parra & Logie, in press).…”

Disruption of visual feature binding in working memory

“…There is already considerable evidence indicating that visual working memory is generally prone to information loss through retrograde interference (e.g., Broadbent & Broadbent, 1981;Brockmole, Wang, & Irwin, 2002;Jiang & Kumar, 2004;Makovski, Sussman, & Jiang, 2008). Furthermore, it is emerging that bound object representations are particularly fragile and susceptible to interference caused by the processing of subsequently encountered stimuli (Allen, Baddeley, & Hitch, 2006;Logie, Brockmole, & Vandenbroucke, 2009;Wheeler & Treisman, 2002). For example, Wheeler and Treisman (2002) extended and modified the Luck and Vogel (1997) procedure, testing memory both for single features (color or shape) and for feature bindings (color and shape together).…”

Binding across space and time in visual working memory

“…A second approach concerns the retention of bound versus individual features over brief delays. Results here suggest that the bindings may be relatively fragile when the interval contains other visual activities, such as encoding or scanning an array or sequence of subsequent items (Allen et al, 2006;Alvarez & Thompson, 2009;Fougnie & Marois, 2009;Logie, Brockmole, & Vandenbroucke, 2009;Shafritz, Gore, & Marois, 2002;Wheeler & Treisman, 2002). A third approach uses the concurrent task procedure to investigate whether attention-demanding activities differentially interfere with the binding process.…”