Detecting and Remembering Change

Successful navigation of dynamic environments requires the ability to adapt to change. However, previous research in the memory literature has shown that change generally impairs performance. A classic finding is that increasing the number of previously presented lists of words makes it more difficult to remember a new list. This phenomenon is referred to as proactive inteference, and it is ubiquitous across a variety of tasks. Recently, we showed that proactive inteference can be reversed when people detect changes by looking back in memory and when they later remember doing so. We describe the mechanisms underlying these effects in a framework that proposes that episodic change detection requires retrieval of previous events and such retrievals can be encoded.

 

Encoding such retrievals leads to the formation of configural representations that preserve the temporal order of information. Accessing these representations allows people to counteract interference. We have shown evidence for this in traditional memory paradigms, situations involving political contradictions, fake news, and the perception and memory for changes in the dynamic activities of others. We are currently conducting experiments to determine the extent to which older and younger adults benefit from change and the extent to which their metacognitive judgments reflect awareness of these effects. 

 

We are currently designing experiments that use eye tracking and electroencephalography (EEG) to provide physiological indices of such change detection and to explore the role of predictive processing in the effects of episodic changes.

Adaptive Memory and Predictive Processing

When individuals experience features that overlap with past events, the cognitive system predicts upcoming features in the environment. The act of making such predictions has consequences for later memory. We are beginning to explore the role of predictive processing in memory for the dynamic everyday activities of others when action sequences are either consistent or changed across occasions. Following on the theme of detecting and remembering change above, we are beginning to examine the memorial consequences of prediction errors on episodic change detection and the downstream consequences on memory for changed activities. These investigations will include both older and younger adults and will be informed by eye tracking and EEG methodologies.

Individual and Age Differences in Free Recall Dynamics

Context theories of episodic memory propose that the ability to isolate prior events during retrieval depends on the match between the contextual information available at retrieval at the contextual representations that are stored with target information. Free recall tasks are thought to depend heavily on the ability to self-initiate context reinstatement, making them ideal to investigate the role of context utilization in episodic memory. The ability to utilize contextual information varies as a function of working memory capacity (WMC), with high-WMC individuals showing more effective context utilization than low-WMC individuals. We are currently examining how episodic memory retrieval in a highly context-dependent task (free recall) depends on WMC ability.

We are also investigating the role of context processing in age-related episodic memory deficits. An inevitable consequence of healthy aging is impairment in the ability to remember prior episodes. Age-related episodic memory deficits are most pronounced when little environmental support is available to cue earlier memories. These deficits are also heightened when similar memories compete during retrieval. This line of research is aimed at understanding the mechanisms that underlie age-related episodic memory deficits in free recall from multiple sources of information.

 

In both of these lines of research, we leverage the flexible analysis options of free recall to examine how individuals differ in the context utilization that allows them to retrieve information from target episodes while avoiding unwanted intrusions from other past episodes. We are currently conducting experiments to examine how these individuals initiate their retrieval, monitor the accuracy of their responses, and decide what information to report.