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Biology subjects

Diamond, N. B.

Publications and source records attributed to Diamond, N. B..

3 recordsLinked to original sources

Remembrance with gazes passed: Eye movements precede continuous recall of episodic details of real-life events

Autobiographical memory entails reconstructing the visual features of past events. Eye movements are associated with vivid autobiographical recollection, but this research has yet to capitalize on the high temporal resolution of eye-tracking data. We aligned eye movement data with participants simultaneous free recall of a verified real-life event, allowing us to assess the temporal correspondence of saccades to production of episodic and non-episodic narrative content at the millisecond level. Eye movements reliably predicted subsequent episodic - but not non-episodic - details by 250-1100 ms, suggesting that they facilitate episodic recollection by reinstating spatiotemporal context during vivid recollection. Assessing the relationship of oculomotor responses to naturalistic memory informs theory as well as diagnosis and treatment of conditions involving pathological recollection, such as Alzheimers disease and post-traumatic stress disorder (PTSD).

neuroscience↗

Sleep selectively and durably enhances real-world sequence memory

Sleep is thought to play a critical role in the retention of episodic memories. Yet it remains unclear whether and how sleep actively transforms memory for specific experiences. More generally, little is known about sleeps effects on memory for multidimensional real-world experiences, both overnight and in the days to months that follow. In an exception to the law of forgetting, we showed that sleep actively and selectively improves retrieval of a one-time real-world experience (a controlled but immersive art tour) - specifically boosting memory for the order of tour items (sequential associations), but not perceptual details from the tour (featural associations). This above-baseline increase in sequence memory was not evident after a matched period of wakefulness. Moreover, the sleep-induced advantage of sequence over featural memory grew over time up to one-year post-encoding. Finally, overnight polysomnography showed that sleep-related memory enhancement was associated with the duration and neurophysiological hallmarks of slow-wave sleep previously linked to neural replay, particularly spindle-slow wave coupling. These results suggest that sleep serves a crucial and selective role in enhancing sequential organization in episodic memory at the expense of specific details, linking sleep-related neural mechanisms to the transformation and enhancement of memory for complex real-life experiences. Significance StatementSleep affects the retention of episodic memories. Yet, it remains unclear whether sleep active transforms how we remember past experiences, overnight and beyond. We investigated memory for different dimensions underlying a dynamic real-world event - sequential associations versus atemporal featural associations - before and after sleep or wakefulness, and serially up to a year later. Sleep actively and selectively enhanced sequence memory, with this preferential sequence retention growing with time. Overnight memory enhancement is associated with the duration and neurophysiological hallmarks of slow-wave sleep previously linked to sequential neural replay, particularly spindle-slow wave coupling. Our findings support an active role for sleep in transforming different aspects of real-world memory, with sequence structure coming to dominate long-term memory for dynamic real-world experiences.

neuroscience↗

Optimizing learning via real-time neural decoding

BackgroundSpectral features of human electroencephalographic (EEG) recordings during learning predict subsequent recall variability. New methodCapitalizing on these fluctuating neural features, we develop a non-invasive closed-loop (NICL) system for real-time optimization of human learning. Participants play a virtual navigation and memory game; recording multi-session data across days allowed us to build participant-specific classification models of recall success. In subsequent closed-loop sessions, our platform manipulated the timing of memory encoding, selectively presenting items during periods of predicted good or poor memory function based on EEG features decoded in real time. ResultsWe observed greater memory modulation (difference between recall rates when presenting items during predicted good vs. poor learning periods) for participants with higher out-of-sample classification accuracy. Comparison with Existing MethodsThis study demonstrates greater-than-chance memory decoding from EEG recordings in a naturalistic virtual navigation task with greater real-world validity than basic word-list recall paradigms. Here we modulate memory by timing stimulus presentation based on noninvasive scalp EEG recordings, whereas prior closed-loop studies for memory improvement involved intracranial recordings and direct electrical stimulation. Other noninvasive studies have investigated the use of neurofeedback or remedial study for memory improvement. ConclusionsThese findings present a proof-of-concept for using non-invasive closed-loop technology to optimize human learning and memory through principled stimulus timing, but only in those participants for whom classifiers reliably predict out-of-sample memory function.

neuroscience↗