S3E6 - Hongi Ngo: Exploring Closed-Loop Auditory Stimulation

Update: 2025-08-23

Description

We're joined by Hongi Ngo, who developed a revolutionary technique for manipulating sleep oscillations during his PhD. Closed-loop Auditory Stimulation (CLAS), which uses bursts of pink noise which are carefully timed to a particular phase of an existing brain oscillation to either boost or dampen the target oscillation. It has been used to selectively strengthen or weaken memories, improve the immune response, reduce epileptic seizures, and even potentially to slow down age related cognitive decline.

Hongi tells us how he got got the idea for CLAS, explains how it works, and tells us about some of his existing studies. He talks about combining CLAS with Targeted Memory Reactivation (TMR) and discusses the ideas for future of brain modulation methods with techniques such as transcranial magnetic stimulation (TMS).

Some of the key papers discussed are:

Auditory closed-loop stimulation of the sleep slow oscillation enhances memory (2013)

Auditory closed-loop stimulation of EEG slow oscillations strengthens sleep and signs of its immune-supportive function (2017)

Thalamic spindles promote memory formation during sleep thrugh triple phase-locking of cortical, thalamic and hippocampal rhythms (2017)

Examining the optimal timing for closed-loop auditory stimulation of slow-wave sleep in young and older adults (2019)

Auditory stimulation during sleep suppresses spike activity in benign epilepsy with centrotemporal spikes (2021)

Shaping overnight consolidation via slow-oscillation closed-loop targeted memory reactivation (2022)

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