Research

How do AGE-RELATED cognitive control changes influence Memory and cognition?

Does reduced cognitive control promote the processing and usage of task-irrelevant information?

The inability to focus attention on target information in the face of distractors is typically associated with processing speed and memory decrements. There are certain situations, however, in which seemingly irrelevant information in one context becomes relevant in a future one.  

Across a series of experiments, we showed that older adults (who typically display reduced cognitive control) conceptually processed task-irrelevant words presented in an initial incidental encoding phase and subsequently used those words to answer general knowledge questions (Amer & Hasher, 2014; Psychol Sci). Young adults, on the other hand, did not benefit from the distractor words and failed to show distractor knowledge on other conceptually based memory tasks (Amer et al., 2018; Memory). Thus, a broader focus of attention, afforded by reduced control, may result in processing, and maintaining access to, task-irrelevant information that can be used in future memory tasks (Amer et al., 2016; Trends Cogn Sci).

How does reduced control shape memory representations?

Although there is evidence that reduced control is associated with memory for task-irrelevant information, the nature of those memory representations (for example, whether they contain both task relevant and irrelevant information) is poorly understood.

We showed that reduced control in older adults in associated with bound targets and distractors in memory (Amer et al., 2020; Psychol Sci). Specifically, we showed that when re-presented with a target item that was previously paired with distractor, older, but not young, adults show reactivation of the previously associated distractor, as evidenced by enhanced priming for those distractors relative to non-reactivated distractors. This finding provides key insight into how irrelevant information is stored in memory, and illustrates that, with reduced cognitive control, concurrently presented target and distractor information are stored as bound memory representations. We recently expanded on this idea and proposed that older adults’ memory representations not only include irrelevant information cued by the environment, but also include no-longer-relevant information that was never “deleted” and task-unrelated thoughts and/or prior knowledge elicited by the target information. Thus, contrary to the view that older adults’ memories reflect sparse records of experience, this work suggested that older adults store too much information in memory (Amer et al., 2022; Trends Cogn Sci).  

What is the neural basis of reduced control and how does it impact attention and memory processes?

While much work has examined the relationship between reduced control and the encoding and memory of task-irrelevant information at the behavioral level, little is known about the neural mechanisms that underlie this effect. 

We demonstrated that the interaction between a network of regions implicated in cognitive control and the default mode network (DMN; a set of regions involved in internal cognition and typically deactivated during externally oriented tasks), was associated with increased encoding of, and future memory for, distractors (Amer et al., 2016; Neuroimage). This suggests that lapses in attention, and resulting memory for distractors, might be attributed to reduced allocation of resources to cognitive control regions. In a more recent study, we showed that although the interaction between cognitive control and DMN networks can occasionally interfere with memory for arbitrary associations, it can have the opposite effect on memory for meaningful associations that are consistent with prior knowledge (Amer et al., 2019; Cereb Cortex). These findings illustrate that reduced control, characterized by increased interactions between control and default mode regions, influences the types of information that are encoded and retained in memory.