Awake ripples enhance emotional memory encoding in the human brain

Abstract:

Enhanced memory for emotional experiences is hypothesized to depend on amygdala-hippocampal interactions during memory consolidation. Here we show using intracranial recordings from the human amygdala and the hippocampus during an emotional memory encoding and discrimination task increased awake ripples after encoding of emotional, compared to neutrally-valenced stimuli. Further, post-encoding ripple-locked stimulus similarity is predictive of later memory discrimination. Ripple-locked stimulus similarity appears earlier in the amygdala than in hippocampus and mutual information analysis confirms amygdala influence on hippocampal activity. Finally, the joint ripple-locked stimulus similarity in the amygdala and hippocampus is predictive of correct memory discrimination. These findings provide electrophysiological evidence that post-encoding ripples enhance memory for emotional events.

Authors:

• Haoxin Zhang

• Ivan Skelin

• Shiting Ma

• Michelle Paff

• Lilit Mnatsakanyan

• Michael A. Yassa

• Robert T. Knight

• Jack J. Lin

Date: 2024

DOI: https://doi.org/10.1038/s41467-023-44295-8

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Gender bias in academia: A lifetime problem that needs solutions

Summary:

Despite increased awareness of the lack of gender equity in academia and a growing number of initiatives to address issues of diversity, change is slow, and inequalities remain. A major source of inequity is gender bias, which has a substantial negative impact on the careers, work-life balance, and mental health of underrepresented groups in science. Here, we argue that gender bias is not a single problem but manifests as a collection of distinct issues that impact researchers’ lives. We disentangle these facets and propose concrete solutions that can be adopted by individuals, academic institutions, and society.

Authors:

• Anaïs Llorens

• Athina Tzovara

• Ludovic Bellier

• Ilina Bhaya-Grossman

• Aurélie Bidet-Caulet

• William K Chang

• Zachariah R Cross

• Rosa Dominguez-Faus

• Adeen Flinker

• Yvonne Fonken

• Mark A Gorenstein

• Chris Holdgraf

• Colin W Hoy

• Maria V Ivanova

• Richard T Jimenez

• Soyeon Jun

• Julia WY Kam

• Celeste Kidd

• Enitan Marcelle

• Deborah Marciano

• Stephanie Martin

• Nicholas E Myers

• Karita Ojala

• Anat Perry

• Pedro Pinheiro-Chagas

• Stephanie K Riès

• Ignacio Saez

• Ivan Skelin

• Katarina Slama

• Brooke Staveland

• Danielle S Bassett

• Elizabeth A Buffalo

• Adrienne L Fairhall

• Nancy J Kopell

• Laura J Kray

• Jack J Lin

• Anna C Nobre

• Dylan Riley

• Anne-Kristin Solbakk

• Joni D Wallis

• Xiao-Jing Wang

• Shlomit Yuval-Greenberg

• Sabine Kastner

• Robert T Knight

• Nina F Dronkers

Date: 2021

DOI: https://doi.org/10.1016/j.neuron.2021.06.002

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Coupling between slow-waves and sharp-wave ripples organizes distributed neural activity during sleep in humans

Abstract:

Hippocampal-dependent memory consolidation during sleep is hypothesized to depend on the synchronization of distributed neuronal ensembles, organized by the hippocampal sharp-wave ripples (SWRs, 80-150 Hz) and subcortical/cortical slow-waves (0.5-4 Hz). However, the precise role of SWR-slow-wave interactions in synchronizing subcortical/cortical neuronal activity is unclear. Here, we leverage intracranial electrophysiological recordings from the human hippocampus, amygdala, temporal and frontal cortices, to examine activity modulation and cross-regional coordination during SWRs. Hippocampal SWRs are associated with widespread modulation of high frequency activity (HFA; 70-200 Hz) a measure of local neuronal activation. This peri-SWR HFA modulation is predicted by the coupling between hippocampal SWRs and local subcortical/cortical slow-waves. Finally, local cortical slow-wave phase offsets during SWRs predicted functional connectivity between the frontal and temporal cortex. These findings suggest a selection mechanism wherein hippocampal SWR and cortical slow-wave synchronization governs the transient engagement of distributed neuronal populations supporting hippocampal-dependent memory consolidation.

Authors:

• Ivan Skelin

• Haoxin Zhang

• Jie Zheng

• Shiting Ma

• Bryce A Mander

• Olivia Kim Mcmanus

• Sumeet Vadera

• Robert T Knight

• Bruce L McNaughton

• Jack J Lin

Date: 2020

DOI: https://doi.org/10.1101/2020.05.24.113480

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