Categories: Sleep and memory

Augmenting hippocampal–prefrontal neuronal synchrony during sleep enhances memory consolidation in humans

Sleep helps stabilize long-term memories, for example declarative hippocampal-dependent memories have been suggested to benefit from synchronization of neuronal activity in hippocampus and cortex during NREM sleep. Working with epilepsy patients implanted with intracranial electrodes for clinical reasons, we studied this process with single neuron resolution. We used electrical pulses in the prefrontal cortex, precisely […]

Disrupted neural correlates of anesthesia and sleep reveal early circuit dysfunctions in Alzheimer models

Alzheimer’s disease (AD) begins with a decades-long presymptomatic phase, well before the onset of memory decline and global disturbances in sleep architecture. Does hippocampal circuit activity and its homeostasis change at these early stages, and does that occur in particular behavioral states? A collaborative study with the lab of Inna Slutsky combines electrophysiology and calcium imaging […]

Local Targeted Memory Reactivation in Human Sleep

In this research, we performed targeted memory reactivation (TMR) locally in one side of the brain to improved memories stored in a single hemisphere: Participants learned to associate words with left or right visual field locations while contextual odor was present. Presenting this odor again to a single nostril during post-learning naps selectively promoted memory […]

Local Sleep Oscillations: Implications for Memory Consolidation

Memory consolidation during sleep is thought to depend on coordinated interplay of cortical slow waves, sleep spindles, and hippocampal ripples, but direct evidence is lacking.  I developed a real-time, closed-loop system triggering intra-cortical electrical stimulation based on brain activity, that will be used to study the neurophysiology of memory consolidation processes. Synchronizing stimulation, locked to […]