Promoting visual long-term memories: When do we learn from repetitions of visuospatial arrays?

Abstract

Repeated exposure is assumed to promote long-term learning. This is demonstrated by the so-called “Hebb-effect”: when short lists of verbal or spatial materials are presented sequentially for an immediate serial recall test, recall improves with list repetition. This repetition benefit, however, is not ubiquitous. Previous studies found little or no performance improvement for repetitions of visuospatial arrays (e.g., arrays of colored squares). Across eight experiments with college students and Prolific samples, we investigated which factors promote visuospatial learning by testing all combinations of variables distinguishing between visual-array tasks (brief + simultaneous presentation + a single recognition test) and tasks showing the Hebb effect (slow + sequential presentation + recall test probing all items). Participants profited from repetitions when all items were tested with a recall procedure, but not if the test consisted of recognition. Hence, the key to promote long-term learning is to recall all of the memorized information over the short-term.

Testing Expectations and Retrieval Practice Modulate Repetition Learning of Visuo-Spatial Arrays

“…In contrast, typical Hebb studies use recall tasks in which all presented items are probed (Couture & Tremblay, 2006;Hebb, 1961;Oberauer et al, 2015). By contrasting different testing procedures for visuo-spatial arrays, Souza and Oberauer (2022) found that repetition learning effects were only consistently observed when participants were asked to recall all items of the presented arrays but not if (1) only one item of the presented arrays was recalled, or (2) different types of change detection tasks were used to test working memory.…”

“…This raises the question, why visuo-spatial information is more difficult to learn and how learning could be promoted. Souza and Oberauer (2022) compared the characteristics of studies which consistently replicated the Hebb effect for verbal lists to those studies failing to find this effect for visuo-spatial arrays. After ruling our several candidate factors such as presentation mode (simultaneous vs. sequential), presentation rate, and retention interval duration, they identified the testing procedure as the critical factor for promoting learning of visuo-spatial arrays.…”

“…Although they still observed learning for repeated lists when they were not tested, the learning effect was larger when participants were asked to recall the lists. Souza and Oberauer (2022) proposed that the strongest determinant for longterm learning by repetition is the difficulty of the test. Building on the assumptions of integrative models of working and long-term memory (Cowan, 1999;Oberauer, 2009), they proposed that the working memory representation of every trial will also leave a trace in episodic long-term memory.…”

“…For each participant, 160 unique memory arrays were created randomly anew. The memory arrays were modeled after Souza and Oberauer (2022) and consisted of six colored squares (square size corresponding to 50 x 50 viewport scaled pixels) 2 , which were presented at random locations against a grey (RGB 128 128 128) background (see Figure 2 for an example). The six colors were randomly drawn from a pool of nine discrete colors (RGB): white (255 255 255), black (0 0 0), blue (0 0 255), cyan (0 255 255), lime (0 255 0), yellow (255 255 0), orange (255 128 0), red (255 0 0), and magenta (255 0 255).…”

The Interplay of Long-Term Memory and Working Memory: When Does Object-Color Prior Knowledge Affect Color Visual Working Memory?

“…These results dovetail with other recent findings from our lab pointing to a critical role of testing to favor the interplay of working memory and long-term memory representations. Souza and Oberauer (2022) observed that the long-term learning of repeatedly presented visuospatial information in a working memory task (i.e., a Hebbrepetition paradigm) depended more on the retrieval conditions (namely, the type of memory test and how many elements of the array need to be retrieved) than on presentation mode (simultaneous or sequential) and encoding time (fast or slow presentation rate). Hence future studies may need to focus more on the retrieval demands of the task to understand how to facilitate the storage and use of long-term memory representations to bypass the capacity limits of working memory.…”