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Using intracranial EEG recordings in epilepsy patients, Pacheco-Estefan et al. describe changes in the neural representations of cues and contexts during fear and extinction learning in the human brain.

The authors used intracranial EEG recordings from patients with epilepsy to show that successful intentional forgetting is due to a selective modification of item-specific top-down connections and not simply a degradation of the memory traces.

A neural code for sequences needs to allow the recruitment of plasticity mechanisms that link successive items. New results suggest that this is achieved by coupling gamma band activity to specific phases of theta oscillations.

In this Review, Fell and Axmacher discuss how phase synchronization of neural oscillations facilitates neural communication and plasticity, and thereby promotes memory processes. They propose that working memory and long-term memory might interact through phase–phase and phase–amplitude synchronization in the hippocampus.

The neural processes involved in memory formation for realistic experiences remain poorly understood. Here, the authors found that ripple-like activity in the human hippocampus and neocortex tracks key moments during movie watching and predicts which events are later remembered.

It is believed that fast “ripple” oscillations in the hippocampus play a role in consolidation, a process by which memory traces are stabilized. Here, the authors show that ripples occuring during non-REM sleep trigger “replay” of brain activity associated with previously experienced stimuli.

Here, the authors demonstrate how targeted memory reactivation during NREM sleep enhances memory consolidation through repeated reactivations, characterized by increased hippocampal ripples, cortical spindles, and dynamic hippocampal-cortical interactions.

How prioritization affects the format of visual working memory representations is currently not understood. Analyzing iEEG recordings in epilepsy patients, the authors demonstrate the critical role of recurrent computations and beta frequency oscillations during the selective attention to particular visual working memory content in the PFC.

The amygdala facilitates memory encoding in the hippocampus. Here the authors show, using simultaneous intracranial recordings from these regions, that emotional memory encoding is mediated by the amygdala theta phase to which hippocampal gamma activity and neuronal firing is coupled.

Functional magnetic resonance imaging (fMRI) is a powerful method to understand neural mechanisms of cognition but imaging of small animals can be challenging. The authors present an event-related fMRI platform to visualize the neural fundaments of perceptual and cognitive functions in awake birds.

By tracking brain activity in both normal subjects and in epilepsy patients, the authors demonstrate that there are differences in the time courses of activation to a memory task in the perirhinal cortex and the hippocampus. These results suggest differentiated roles for these two areas during memory tasks.

New memory traces are believed to be reactivated and reorganized during sleep, mediated by the fine-tuned temporal interplay of neocortical slow oscillations, thalamo-cortical spindles and hippocampal ripples. The authors used intracranial recordings in humans to provide, for the first time, direct evidence for a systematic interaction of these oscillations in the human hippocampus.

A structural MRI study suggests that regular exercise training induces plasticity in hippocampal subregions also in young adults. Hippocampal plasticity correlates with changes in spatial memory precision.