The meaning we derive from our experiences is not a simple static extraction of the elements, but is largely based on the order in which those elements occur. Models propose that sequence encoding is supported by interactions between high and low frequency oscillations, such that elements within an experience are represented by neural cell assemblies firing at higher frequencies (i.e. gamma) and sequential order is coded by the specific timing of firing with respect to a lower frequency oscillation (i.e. theta). During episodic sequence memory formation in humans, we provide evidence that items in different sequence positions exhibit relatively greater gamma power along distinct phases of a theta oscillation. Furthermore, this segregation is related to successful temporal order memory. These results provide compelling evidence that memory for order, a core component of an episodic memory, capitalizes on the ubiquitous physiological mechanism of theta-gamma phase-amplitude coupling.

Episodic memories are not veridical records of our lives, but rather are better described as organized summaries of experience. Theories and empirical research suggest that shifts in perceptual, temporal and semantic information lead to a chunking of our continuous experiences into segments, or 'events'. However, the consequences of these contextual shifts on memory formation and organization remains unclear. In a series of three behavioral studies, we introduced context shifts (or 'event boundaries') between trains of stimuli and then examined the influence of the boundaries on several measures of associative memory. In Experiment 1, we found that perceptual event boundaries strengthened associative binding of item-context pairings present at event boundaries.In Experiment 2, we observed reduced temporal order memory for items encoded in distinct events relative to items encoded within the same event, and a trade-off between the speed of processing at boundaries, and temporal order memory for items that flanked those boundaries. Finally, in Experiment 3 we found that event organization imprinted structure on the order in which items were freely recalled. These results provide insight into how boundary-and event-related organizational processes during encoding shape subsequent representations of events in episodic memory.

Episodic memories are not veridical records of our lives, but rather are better described as organized summaries of experience. Theories and empirical research suggest that shifts in perceptual, temporal and semantic information lead to a chunking of our continuous experiences into segments, or 'events'. However, the consequences of these contextual shifts on memory formation and organization remains unclear. In a series of three behavioral studies, we introduced context shifts (or 'event boundaries') between trains of stimuli and then examined the influence of the boundaries on several measures of associative memory. In Experiment 1, we found that perceptual event boundaries strengthened associative binding of item-context pairings present at event boundaries.In Experiment 2, we observed reduced temporal order memory for items encoded in distinct events relative to items encoded within the same event, and a trade-off between the speed of processing at boundaries, and temporal order memory for items that flanked those boundaries. Finally, in Experiment 3 we found that event organization imprinted structure on the order in which items were freely recalled. These results provide insight into how boundary-and event-related organizational processes during encoding shape subsequent representations of events in episodic memory.

The mental contexts in which we interpret experiences are often person-specific, even when the experiences themselves are shared. We developed a geometric framework for mathematically characterizing the subjective conceptual content of dynamic naturalistic experiences. We model experiences and memories as trajectories through word embedding spaces whose coordinates reflect the universe of thoughts under consideration. Memory encoding can then be modeled as geometrically preserving or distorting the shape of the original experience. We applied our approach to data collected as participants watched and verbally recounted a television episode while undergoing functional neuroimaging. Participants' recountings all preserved coarse spatial properties (essential narrative elements), but not fine spatial scale (low-level) details, of the episode's trajectory. We also identified networks of brain structures sensitive to these trajectory shapes. Our work provides insights into how we preserve and distort our ongoing experiences when we encode them into episodic memories.

STARS-Adjunct was a multicenter, open-label effectiveness study of AKL-T01, an app and video-game-based treatment for inattention, as an adjunct to pharmacotherapy in 8–14-year-old children with attention-deficit/hyperactivity disorder (ADHD) on stimulant medication (n = 130) or not on any ADHD medication (n = 76). Children used AKL-T01 for 4 weeks, followed by a 4-week pause and another 4-week treatment. The primary outcome was change in ADHD-related impairment (Impairment Rating Scale (IRS)) after 4 weeks. Secondary outcomes included changes in IRS, ADHD Rating Scale (ADHD-RS). and Clinical Global Impressions Scale—Improvement (CGI-I) on days 28, 56, and 84. IRS significantly improved in both cohorts (On Stimulants: −0.7, p < 0.001; No Stimulants: −0.5, p < 0.001) after 4 weeks. IRS, ADHD-RS, and CGI-I remained stable during the pause and improved with a second treatment period. The treatment was well-tolerated with no serious adverse events. STARS-Adjunct extends AKL-T01’s body of evidence to a medication-treated pediatric ADHD population, and suggests additional treatment benefit.

How our experiences unfold over time define unique trajectories through the relevant representational spaces. Within this geometric framework, one can compare the shape of the trajectory formed by an experience to that defined by our later remembering of that experience. We propose a framework for mapping naturalistic experiences onto geometric spaces that characterize how they unfold over time. We apply this approach to a naturalistic memory experiment which had participants view and recount a video. We found that the shapes of the trajectories formed by participants' recountings were all highly similar to that of the original video, but participants differed in the level of detail they remembered. We also identified a network of brain structures that are sensitive to the "shapes" of our ongoing experiences, and an overlapping network that is sensitive to how we will later remember those experiences.

Although a memory systems view of the medial temporal lobe (MTL) has been widely influential in understanding how memory processes are implemented, a large body of work across humans and animals has converged on the idea that the MTL can support various other decisions, beyond

In order to better understand how concepts might be represented in the brain, we used a cross-modal conceptual priming paradigm to examine how repetition-related activity changes in the brain are related to conceptual priming. During scanning, subjects made natural/manmade judgments on a continuous stream of spoken nouns, written nouns and pictures of objects. Each stimulus either repeated in the same or a different modality with 1-4 intervening trials between repetitions. Behaviorally, participants showed significant perceptual and conceptual priming effects. The fMRI data showed that the conditions associated with the greatest behavioral priming exhibited the largest decreases in BOLD activity in left perirhinal cortex (PRc), as well as a few other regions. Furthermore, the PRc was the only region to show this relationship for the cross-modal conditions alone, where the concept but not the percept repeated. Conversely, repetition-related increases in PRc activity predicted better subsequent memory as assessed by a post-scan recognition test. These results suggest that repetition-related activity changes in the PRc are related both to the speed of access to a repeated concept and to that concept’s later memorability.