Naturalistic stimuli (e.g., movies) provide the opportunity to study lifelike experiences in the lab. While young adults respond to these stimuli in a highly synchronized manner [as indexed by intersubject correlations (ISC) in their neural activity], older adults respond more idiosyncratically. Here, we examine whether eye-movement synchrony (eye-ISC) also declines with age during movie-watching and whether it relates to memory for the movie. Our results show no age-related decline in eye-ISC, suggesting that age differences in neural ISC are not caused by differences in viewing patterns. Both age groups recalled the same number of episodic details from the movie, but older adults recalled proportionally fewer episodic details due to their greater output of semantic and false information. In both age groups, higher eye-ISC related to a higher proportion of internal details and a lower proportion of false information being recalled. Finally, both older and younger adults showed better cued recall for cues taken from within the same event than those spanning an event boundary, further confirming that events are stored in long-term memory as discrete units with stronger associations within than across event boundaries. Taken together, these findings suggest that naturalistic stimuli drive perception in a similar way in younger and older adults, but age differences in neural synchrony further up the information processing stream may contribute to subtle differences in event memory.

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Past research has shown that older adults' reduced inhibitory control causes them to hyper-bind, or form erroneous associations between task-relevant and -irrelevant information. In the current study, we aimed to extend hyper-binding to a novel, implicit memory paradigm. In two experiments, participants viewed pictures of objects superimposed with text and their task was to make speeded categorization judgments about the objects. The encoding phase contained three blocks that varied the potential for binding: no-binding, some-binding, and full-binding. During the no/some-binding blocks, participants decided if the pictured object alone could fit inside a common desk drawer while ignoring the superimposed text. In the no-binding block, the text was a nonword; in the some-binding block, it was an object word. During the full-binding block, participants attended to both the picture and word and decided if both items could fit inside a drawer together. After a delay, participants completed the test phase during which they viewed intact and rearranged pairs from the three encoding blocks and decided if both items could fit in a drawer together. In both experiments, older adults responded faster to intact than rearranged pairs from both the some-and full-binding blocks, suggesting that they had learned both targettarget and target-distractor pairs. Young adults showed no difference in RTs to pairs from either block. These findings suggest that the binding mechanism itself is spared with age; what declines instead is inhibitory control, which serves to limit attention, and ergo binding, to task-relevant information.iii Acknowledgements I would like to thank Dr. Campbell for her constant support and mentorship over the last two years. I have become a much better researcher because of her knowledge, expertise, and the time that she dedicates to her graduate students. I am thankful every day that I was able to complete my degree in her lab. Thank you to my committee members Dr. Emrich and Dr. Mahy for their invaluable insight and support. I would like to thank Sarah Henderson for being an amazing teammate and a sounding board. I could not have asked for a better office-mate and friend to enjoy the highs and lows of graduate school with. I could not imagine the next four years of my Ph.D. without her partnership (and "sad" afternoon muffins). This research could not have been done without Amy Holliday who poured hours of her time into calling older adults, training research assistants, and going above and beyond her responsibilities to help with this project. Finally, thank you to all members of Campbell's Neurocognitive Aging lab, extended BUCAN Lab, and the Face Perception Lab, who all piloted experiments, helped with programming, tested participants, searched for older adults in parking lots, made fresh coffee in the morning, and shared intel on free food from 600F.

Naturalistic stimuli (e.g., movies) provide the opportunity to study lifelike experiences in the lab. While young adults respond to these stimuli in a highly synchronized manner (as indexed by intersubject correlations [ISC] in their neural activity), older adults respond more idiosyncratically. Here, we examine whether eye movement synchrony (eye-ISC) also declines with age during movie-watching and whether it relates to memory for the movie. Our results show no age-related decline in eye-ISC, suggesting that age differences in neural ISC are not caused by differences in viewing patterns. Both age groups recalled the same number of episodic details from the movie, however, older adults recalled more semantic and false information. In both age groups, more recall of false information related to lower eye-ISC. Finally, older adults showed better cued-recall than younger adults across event boundaries, suggesting that older adults may form broader associations across events when encoding everyday experiences.

The ability to recognize identity despite within‐person variability in appearance is likely a face‐specific skill and shaped by experience. Ensemble coding – the automatic extraction of the average of a stimulus array – has been proposed as a mechanism underlying face learning (allowing one to recognize novel instances of a newly learned face). We investigated whether ensemble encoding, like face learning and recognition, is refined by experience by testing participants with upright own‐race faces and two categories of faces with which they lacked experience: other‐race faces (Experiment 1) and inverted faces (Experiment 2). Participants viewed four images of an unfamiliar identity and then were asked whether a test image of that same identity had been in the study array. Each test image was a matching exemplar (from the array), matching average (the average of the images in the array), non‐matching exemplar (a novel image of the same identity), or non‐matching average (an average of four different images of the same identity). Adults showed comparable ensemble coding for all three categories (i.e., reported that matching averages had been present more than non‐matching averages), providing evidence that this early stage of face learning is not shaped by face‐specific experience.