Eye movements and event segmentation: Eye movements reveal age-related differences in event model updating.

People spontaneously segment continuous ongoing actions into sequences of events. Prior research found that gaze similarity and pupil dilation increase at event boundaries and that older adults segment more idiosyncratically than do young adults. We used eye tracking to explore age-related differences in gaze similarity (i.e., the extent to which individuals look at the same places at the same time as others) and pupil dilation at event boundaries. Older and young adults watched naturalistic videos of actors performing everyday activities while we tracked their eye movements. Afterward, they segmented the videos into subevents. Replicating prior work, we found that pupil size and gaze similarity increased at event boundaries. Thus, there were fewer individual differences in eye position at boundaries. We also found that young adults had higher gaze similarity than older adults throughout an entire video and at event boundaries. This study is the first to show that age-related differences in how people parse continuous everyday activities into events may be partially explained by individual differences in gaze patterns. Those who segment less normatively may do so because they fixate less normative regions. Results have implications for future interventions designed to improve encoding in older adults. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Events shape long-term memory for story information.

We segment what we read into meaningful events, each separated by a discrete boundary. How does event segmentation during encoding relate to the structure of story information in long-term memory? To evaluate this question, participants read stories of fictional historical events and then engaged in a post-reading verb arrangement task. In this task, participants saw verbs from each of the events placed randomly on a computer screen, and then they arranged the verbs into groups onscreen based on their understanding of the story. Participants who successfully comprehended the story placed verbs from the same event closer to each other than verbs from different events, even after controlling for orthographic, text-based, semantic, and situational overlap between verbs. Thus, how people structure story information into separate events during online comprehension is associated with how that information is stored in memory. Specifically, story information within an event is bound together in memory more so than information between events.

Cueing natural event boundaries improves memory in people with post-traumatic stress disorder.

People with post-traumatic stress disorder (PTSD) often report difficulty remembering information in their everyday lives. Recent findings suggest that such difficulties may be due to PTSD-related deficits in parsing ongoing activity into discrete events, a process called event segmentation. Here, we investigated the causal relationship between event segmentation and memory by cueing event boundaries and evaluating its effect on subsequent memory in people with PTSD. People with PTSD (n = 38) and trauma-matched controls (n = 36) watched and remembered videos of everyday activities that were either unedited, contained visual and auditory cues at event boundaries, or contained visual and auditory cues at event middles. PTSD symptom severity varied substantial within both the group with a PTSD diagnosis and the control group. Memory performance did not differ significantly between groups, but people with high symptoms of PTSD remembered fewer details from the videos than those with lower symptoms of PTSD. Both those with PTSD and controls remembered more information from the videos in the event boundary cue condition than the middle cue or unedited conditions. This finding has important implications for translational work focusing on addressing everyday memory complaints in people with PTSD.

PTSD is associated with impaired event processing and memory for everyday events.

Current theories of posttraumatic stress disorder (PTSD) propose that memory abnormalities are central to the development and persistence of symptoms. While the most notable memory disturbances in PTSD involve memory for the trauma itself, individuals often have trouble remembering aspects of everyday life. Further, people with PTSD may have difficulty segmenting ongoing activity into discrete units, which is important for our perception and later memory of the activity. The current study investigated whether PTSD diagnosis and symptom severity predicted event segmentation and memory for everyday activities. To do so, 63 people with PTSD and 64 controls with a trauma history watched, segmented, and recalled videos of everyday activities. Viewers with higher PTSD symptom severity showed lower agreement on locations of event boundaries and recalled fewer fine-grained actions than did those with lower symptom severity. These results suggest that PTSD symptoms alter event segmentation, which may contribute to subsequent memory disturbances.

Semantic knowledge attenuates age-related differences in event segmentation and episodic memory.

While semantic and episodic memory may be distinct memory systems, their interdependence is substantial. For instance, decades of work have shown that semantic knowledge facilitates episodic memory. Here, we aim to clarify this interactive relationship by determining whether semantic knowledge facilitates the acquisition of new episodic memories, in part, by influencing an encoding mechanism, event segmentation. In the current study, we evaluated the extent to which semantic knowledge shapes how people segment ongoing activity and how such knowledge-related benefits in segmentation affect episodic memory performance. To investigate these effects, we combined data across three studies that had young and older adults segment and remember videos of everyday activities that were either familiar or unfamiliar to their age group. We found age-related differences in event-segmentation ability and memory performance, but only when older adults lacked semantic knowledge. Most importantly, when they had access to relevant semantic knowledge, older adults segmented and remembered information similar to young adults. Our findings indicate that older adults can use semantic knowledge to effectively encode and retrieve everyday information. These effects suggest that future interventions can leverage older adults' intact semantic knowledge to attenuate age-related deficits in event segmentation and episodic long-term memory.

Knowledge guides attention to goal-relevant information in older adults.

How does viewers' knowledge guide their attention while they watch everyday events, how does it affect their memory, and does it change with age? Older adults have diminished episodic memory for everyday events, but intact semantic knowledge. Indeed, research suggests that older adults may rely on their semantic memory to offset impairments in episodic memory, and when relevant knowledge is lacking, older adults' memory can suffer. Yet, the mechanism by which prior knowledge guides attentional selection when watching dynamic activity is unclear. To address this, we studied the influence of knowledge on attention and memory for everyday events in young and older adults by tracking their eyes while they watched videos. The videos depicted activities that older adults perform more frequently than young adults (balancing a checkbook, planting flowers) or activities that young adults perform more frequently than older adults (installing a printer, setting up a video game). Participants completed free recall, recognition, and order memory tests after each video. We found age-related memory deficits when older adults had little knowledge of the activities, but memory did not differ between age groups when older adults had relevant knowledge and experience with the activities. Critically, results showed that knowledge influenced where viewers fixated when watching the videos. Older adults fixated less goal-relevant information compared to young adults when watching young adult activities, but they fixated goal-relevant information similarly to young adults, when watching more older adult activities. Finally, results showed that fixating goal-relevant information predicted free recall of the everyday activities for both age groups. Thus, older adults may use relevant knowledge to more effectively infer the goals of actors, which guides their attention to goal-relevant actions, thus improving their episodic memory for everyday activities.

Influences of domain knowledge on segmentation and memory.

Much research has shown that experts possess superior memory in their domain of expertise. This memory benefit has been proposed to be the result of various encoding mechanisms, such as chunking and differentiation. Another potential encoding mechanism that is associated with memory is event segmentation, which is the process by which people parse continuous information into meaningful, discrete units. Previous research has found evidence that segmentation, to some extent, is affected by top-down processing. To date, few studies have investigated the influence of expertise on segmentation, and questions about expertise, segmentation ability, and their impact on memory remain. The goal of the current study was to investigate the influence of expertise on segmentation and memory ability for two different domains: basketball and Overwatch. Participants with high and low knowledge for basketball and with low knowledge for Overwatch viewed and segmented videos at coarse and fine grains, then completed memory tests. Differences in segmentation ability and memory were present between experts and control novices, specifically for the basketball videos; however, experts' segmentation only predicted memory for activities for which knowledge was lacking. Overall, this research suggests that experts' superior memory is not due to their segmentation ability and contributes to a growing body of literature showing evidence supporting conceptual effects on segmentation.

Differential effects of knowledge and aging on the encoding and retrieval of everyday activities.

We deconstruct continuous streams of action into smaller, meaningful events. Research has shown that the ability to segment continuous activity into such events and remember their contents declines with age; however, knowledge improves with age. We investigated how young and older adults use knowledge to more efficiently encode and later remember information from everyday events by having participants view a series of self-paced slideshows depicting everyday activities. For some activities, older adults produce more normative scripts than do young adults (older adult activities) and for other activities, young adults produce more normative scripts than do older adults (young adult activities). Overall, participants viewed event boundaries longer than within events (i.e., the event boundary advantage) replicating prior research (e.g., Hard, Recchia, & Tversky, 2011). Importantly, older adults demonstrated the boundary advantage for the older adult activities but not the young adult activities, and they also had better recognition memory for the older adult activities than the young adult activities. We also found that the magnitude of a participant's boundary advantage was associated with better memory, but only for the less knowledgeable activities. Results indicate that older adults use their intact knowledge to better encode and remember everyday activities, but that knowledge and event segmentation may have independent influences on event memory.

Does semantic knowledge influence event segmentation and recall of text?

Knowledge benefits episodic memory, particularly when provided before encoding (Anderson & Pichert in Journal of Verbal Learning and Verbal Behavior, 17(1), 1-12, 1978; Bransford & Johnson in Journal of Verbal Learning and Verbal Behavior, 11(6), 717-726, 1972). These benefits can occur through several encoding mechanisms, one of which may be event segmentation. Event segmentation is one's ability to parse information into meaningful units as an activity unfolds. The current experiment evaluated whether two top-down manipulations-providing context or perspective taking-influence the segmentation and memory of text. For the ambiguous texts in Experiment 1, half the participants received context in the form of a title, whereas the other half received no context. For the text in Experiment 2, half the participants read from the perspective of a burglar and the other half read from the perspective of a home buyer. In both experiments, participants read the passages, recalled the information, and then segmented the passages into meaningful units. Consistent with previous findings, participants who received context recalled more information compared with those who received no context, and participants in one perspective were more likely to recall information relevant to their perspective. Most importantly, we found that context and perspective facilitated more normative segmentation; however, the differences were small and suggest that effects of top-down processing on the segmentation of text may be modest at best. Thus, event segmentation processes that operate during text comprehension are influenced by semantic knowledge but may be more heavily driven by other factors (e.g., perceptual cues).

Temporal Chunking Makes Life's Events More Memorable.

Declines in episodic memory accompany both healthy aging and age-related diseases, such as dementia. Given that memory complaints are common in the aging population, a wealth of research has evaluated the underlying mechanisms of these declines and explored strategy interventions that could offset them. In the current paper, we describe a newer approach to improving memory: event segmentation training. Event segmentation is an encoding strategy in which individuals parse continuous activity into meaningful chunks. The ability to segment activity is associated with later memory for the events, but unfortunately, this segmentation ability declines with age. Importantly, interventions designed to improve event segmentation have resulted in memory improvements for both young and older adults. We will review these past experiments as well as some new event segmentation training work that uses older adults' semantic knowledge to improve their segmentation and episodic memory. We believe that future research on event segmentation is a promising avenue for improving older adults' ability to remember everyday activities.

Attentional focus affects how events are segmented and updated in narrative reading.

Readers generate situation models representing described events, but the nature of these representations may differ depending on the reading goals. We assessed whether instructions to pay attention to different situational dimensions affect how individuals structure their situation models (Exp. 1) and how they update these models when situations change (Exp. 2). In Experiment 1, participants read and segmented narrative texts into events. Some readers were oriented to pay specific attention to characters or space. Sentences containing character or spatial-location changes were perceived as event boundaries-particularly if the reader was oriented to characters or space, respectively. In Experiment 2, participants read narratives and responded to recognition probes throughout the texts. Readers who were oriented to the spatial dimension were more likely to update their situation models at spatial changes; all readers tracked the character dimension. The results from both experiments indicated that attention to individual situational dimensions influences how readers segment and update their situation models. More broadly, the results provide evidence for a global situation model updating mechanism that serves to set up new models at important narrative changes.

Event segmentation improves event memory up to one month later.

When people observe everyday activity, they spontaneously parse it into discrete meaningful events. Individuals who segment activity in a more normative fashion show better subsequent memory for the events. If segmenting events effectively leads to better memory, does asking people to attend to segmentation improve subsequent memory? To answer this question, participants viewed movies of naturalistic activity with instructions to remember the activity for a later test, and in some conditions additionally pressed a button to segment the movies into meaningful events or performed a control condition that required button-pressing but not attending to segmentation. In 5 experiments, memory for the movies was assessed at intervals ranging from immediately following viewing to 1 month later. Performing the event segmentation task led to superior memory at delays ranging from 10 min to 1 month. Further, individual differences in segmentation ability predicted individual differences in memory performance for up to a month following encoding. This study provides the first evidence that manipulating event segmentation affects memory over long delays and that individual differences in event segmentation are related to differences in memory over long delays. These effects suggest that attending to how an activity breaks down into meaningful events contributes to memory formation. Instructing people to more effectively segment events may serve as a potential intervention to alleviate everyday memory complaints in aging and clinical populations. (PsycINFO Database Record

Situation model updating in young and older adults: Global versus incremental mechanisms.

Readers construct mental models of situations described by text. Activity in narrative text is dynamic, so readers must frequently update their situation models when dimensions of the situation change. Updating can be incremental, such that a change leads to updating just the dimension that changed, or global, such that the entire model is updated. Here, we asked whether older and young adults make differential use of incremental and global updating. Participants read narratives containing changes in characters and spatial location and responded to recognition probes throughout the texts. Responses were slower when probes followed a change, suggesting that situation models were updated at changes. When either dimension changed, responses to probes for both dimensions were slowed; this provides evidence for global updating. Moreover, older adults showed stronger evidence of global updating than did young adults. One possibility is that older adults perform more global updating to offset reduced ability to manipulate information in working memory.

APOE ε4 genotype predicts memory for everyday activities.

The apolipoprotein E (ApOE) ε4 allele is associated with neuropathological buildup of amyloid in the brain, and with lower performance on some laboratory measures of memory in some populations. In two studies, we tested whether ApOE genotype affects memory for everyday activities. In Study 1, participants aged 20-79 years old (n = 188) watched movies of actors engaged in daily activities and completed memory tests for the activities in the movies. In Study 2, cognitively healthy and demented older adults (n = 97) watched and remembered similar movies, and also underwent structural MRI scanning. All participants provided saliva samples for genetic analysis. In both samples we found that, in older adults, ApOE ε4 carriers demonstrated worse everyday memory performance than did ε4 noncarriers. In Study 2, ApOE ε4 carriers had smaller medial temporal lobes (MTL) volumes, and MTL volume mediated the relationship between ApOE genotype and everyday memory performance. These everyday memory tasks measure genetically determined cognitive decline that can occur prior to a clinical diagnosis of dementia. Further, these tasks are easily administered and may be a useful clinical tool in identifying ε4 carriers who may be at risk for MTL atrophy and further cognitive decline that is a common characteristic of the earliest stages of Alzheimer's disease.

Does strategy training reduce age-related deficits in working memory?

BACKGROUND: Older adults typically perform worse on measures of working memory (WM) than do young adults; however, age-related differences in WM performance might be reduced if older adults use effective encoding strategies. OBJECTIVE: The purpose of the current experiment was to evaluate WM performance after training individuals to use effective encoding strategies. METHODS: Participants in the training group (older adults: n = 39; young adults: n = 41) were taught about various verbal encoding strategies and their differential effectiveness and were trained to use interactive imagery and sentence generation on a list-learning task. Participants in the control group (older: n = 37; young: n = 38) completed an equally engaging filler task. All participants completed a pre- and post-training reading span task, which included self-reported strategy use, as well as two transfer tasks that differed in the affordance to use the trained strategies - a paired-associate recall task and the self-ordered pointing task. RESULTS: Both young and older adults were able to use the target strategies on the WM task and showed gains in WM performance after training. The age-related WM deficit was not greatly affected, however, and the training gains did not transfer to the other cognitive tasks. In fact, participants attempted to adapt the trained strategies for a paired-associate recall task, but the increased strategy use did not benefit their performance. CONCLUSIONS: Strategy training can boost WM performance, and its benefits appear to arise from strategy-specific effects and not from domain-general gains in cognitive ability.

Event segmentation ability uniquely predicts event memory.

Memory for everyday events plays a central role in tasks of daily living, autobiographical memory, and planning. Event memory depends in part on segmenting ongoing activity into meaningful units. This study examined the relationship between event segmentation and memory in a lifespan sample to answer the following question: Is the ability to segment activity into meaningful events a unique predictor of subsequent memory, or is the relationship between event perception and memory accounted for by general cognitive abilities? Two hundred and eight adults ranging from 20 to 79years old segmented movies of everyday events and attempted to remember the events afterwards. They also completed psychometric ability tests and tests measuring script knowledge for everyday events. Event segmentation and script knowledge both explained unique variance in event memory above and beyond the psychometric measures, and did so as strongly in older as in younger adults. These results suggest that event segmentation is a basic cognitive mechanism, important for memory across the lifespan.

Action perception predicts action performance.

Everyday action impairments often are observed in demented older adults, and they are common potential barriers to functional independence. We evaluated whether the ability to segment and efficiently encode activities is related to the ability to execute activities. Further, we evaluated whether brain regions important for segmentation also were important for action performance. Cognitively healthy older adults and those with very mild or mild dementia of the Alzheimer's type watched and segmented movies of everyday activities and then completed the Naturalistic Action Test. Structural MRI was used to measure volume in the dorsolateral prefrontal cortex (DLPFC), medial temporal lobes (MTL), posterior cortex, and anterior cingulate cortex (ACC). Dementia status and the ability to segment everyday activities strongly predicted naturalistic action performance, and MTL volume largely accounted for this relationship. In addition, the current results supported the Omission-Commission Model: Different cognitive and neurological mechanisms predicted different types of action error. Segmentation, dementia severity, and MTL volume predicted everyday omission errors, DLPFC volume predicted commission errors, and ACC volume predicted action additions. These findings suggest that event segmentation may be critical for effective action production, and that the segmentation and production of activities may recruit the same event representation system.

Medial temporal lobe volume predicts elders' everyday memory.

Deficits in memory for everyday activities are common complaints among healthy and demented older adults. The medial temporal lobes and dorsolateral prefrontal cortex are both affected by aging and early-stage Alzheimer's disease, and are known to influence performance on laboratory memory tasks. We investigated whether the volume of these structures predicts everyday memory. Cognitively healthy older adults and older adults with mild Alzheimer's-type dementia watched movies of everyday activities and completed memory tests on the activities. Structural MRI was used to measure brain volume. Medial temporal but not prefrontal volume strongly predicted subsequent memory. Everyday memory depends on segmenting activity into discrete events during perception, and medial temporal volume partially accounted for the relationship between performance on the memory tests and performance on an event-segmentation task. The everyday-memory measures used in this study involve retrieval of episodic and semantic information as well as working memory updating. Thus, the current findings suggest that during perception, the medial temporal lobes support the construction of event representations that determine subsequent memory.