SELECTED RESEARCH PROJECTS
Does remembering new information help improve forgetting?
Forgetting is often experienced as a flaw in our memory or an obstacle to learning. Not being able to remember or recall things can be frustrating. But forgetting actually benefits our cognitive system and mental health. It helps protect memory from negative thoughts, traumatic memories or from being overloaded with irrelevant information. The crucial question is: Can we improve forgetting? Our investigation into whether remembering new information aids in the forgetting of what is no longer relevant revealed little evidence. Strikingly, instructions to forget by replacing old information with new do not help unless the new information is closely related, possibly due to interference during memory retrieval. Also, how memorable or valuable the new information is does not affect the forgetting of old information. While we have many ways to boost remembering, our ability to control forgetting seems to be quite limited.
What do we recall about things we just focused on?
Studies on attribute amnesia (AA) reveal that people can fully process a simple feature (like identifying a letter among numbers), only to fail to report it a moment later (e.g., the identity of that letter) when asked unexpectedly. This likely reflects a lack of working memory consolidation. However, real-world objects seem to resist attribute amnesia. Using a surprise test, we found that people can recognize real-world objects they have just attended to on an exemplar level (e.g., indicating whether they saw pumpkin pie or apple pie), but they cannot remember specific details (like if the pie was cut or whole). We also showed that meaningful objects are partly resistant to attribute amnesia due to long-term memory support (Sasin, Markov & Fougnie, 2023).
Top-down attention is more effective than bottom-up attention for forming long-term memories.
Does long-term memory strength depend on the type of attention? We examined how well people remembered two types of objects: related nontargets that caught attention due to a shared color feature with the target (top-down attention) and salient distractors that captured attention due to rapid flickering (bottom-up attention). Both distractors grabbed equal attention, but the related nontargets were better remembered than the salient distractors (Sasin, 2021). Thus, the effects of salience are short-lived and do not lead to strong encoding in long-term memory. However, when attention is purposefully shifted towards information, it is remembered better, even when memorization is not required.
Can we purposefully erase information from our active memory when it is no longer needed?
In our daily lives, we are bombarded with abundant information. Yet, our working memory has a limited capacity to retain information. Consequently, it is crucial to forget information that is no longer relevant, thereby conserving valuable working memory capacity. Furthermore, forgetting is important in ensuring that outdated information does not influence our attentional focus or behavior. My research explores whether information in working memory can be deprioritized and removed and tests how this affects external attention. For example, we found that attempting to forget a single object in working memory results in its rapid yet partial deactivation, and this residual activation can still subtly influence the focus of our attention (Sasin, Morey, & Nieuwenstein, 2017). Furthermore, we found that training across different days does not lead to the complete forgetting of a single object in memory (Sasin, Sense, Nieuwenstein, & Fougnie, 2022). We also showed that when only one feature of an object (like color) is cued as no longer relevant, it can be deactivated to a level that doesn’t influence attention This provides evidence for the interaction between internal prioritization and external attention at the features level (Sasin & Fougnie, 2020).
Multiple states of working memory and their influence on attention
Working memory activations direct our attention toward relevant perceptual input. However, sometimes, we hold in mind information that is currently irrelevant, yet this memory activation can still guide our attention toward similar things in the environment. My research shows how various task demands affect working memory activation and how these memory fluctuations influence attentional selection. For instance, deep encoding, such as understanding a word’s meaning (e.g., is a ‘bird’ living or non-living thing?), leads to memory activation that directs attention in a subsequent unrelated task. Thus, after processing the meaning of the word ‘bird,’ an unrelated picture of a bird can capture your attention, even when you should focus on a different task. Conversely, shallow encoding, like judging whether the word ‘bird’ is in uppercase or lowercase, does not lead to such attentional capture (Sasin, Nieuwenstein, & Johnson, 2015). Interestingly, attentional capture from deep encoding is eliminated if a memory-demanding task follows the encoding (i.e., after thinking of a bird, you must remember something else), indicating that new working memory information can overwrite old activation. However, capture persists if the task requires remembering the word, regardless of subsequent memory demands (Sasin & Nieuwenstein, 2016). These findings demonstrate that memory activations stemming from deep processing can influence our attention and that attentional capture reflects working memory activation levels.
