Evidence map›Paper›PMID 34619386›Full record

ArticleBrain stimulation

Identifying the neurophysiological effects of memory-enhancing amygdala stimulation using interpretable machine learning.

Mohammad S E Sendi, Cory S Inman, Kelly R Bijanki, Lou Blanpain, James K Park, Stephan Hamann, Robert E Gross, Jon T Willie, Babak Mahmoudi

Abstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in Brain stimulation. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

5 citing papers in PubMed.

  1. Review
  2. Article
  3. Article
  4. Review
  5. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Mohammad S E SendiWallace H. Coulter Department of Biomedical Engineering at Georgia Institute of Technology and Emory University, 313 Ferst Dr NW, Atlanta, 30332, GA, USA; Department of Electrical and Computer Engineering at Georgia Institute of Technology, 777 Atlantic Dr, Atlanta, GA, 30313, USA.
Cory S InmanDepartment of Psychology at University of Utah, 380 1530 E, Salt Lake City, UT, 84112, United States.
Kelly R BijankiDepartment of Neurosurgery at Baylor College of Medicine, 7200 Cambridge St 9th Floor, Houston, TX, 77030, USA.
Lou BlanpainNeuroscience Graduate Program at Emory University, 1462 Clifton Rd. Suite 314, Atlanta, GA, 30322, USA.
James K ParkDepartment of Neurosurgery at Emory University, 100 Woodruff Circle, Atlanta, GA, 30322, USA.
Stephan HamannDepartment of Psychology at Emory University, 36 Eagle Row, Atlanta, GA, 3032, USA.
Robert E GrossWallace H. Coulter Department of Biomedical Engineering at Georgia Institute of Technology and Emory University, 313 Ferst Dr NW, Atlanta, 30332, GA, USA; Department of Neurosurgery at Emory University, 100 Woodruff Circle, Atlanta, GA, 30322, USA; Department of Neurology at Emory University, 12 Executive Park Dr NE, Atlanta, GA, 30322, USA.
Jon T WillieDepartment of Neurology at Washington University School of Medicine in Saint Louis, 660 S. Euclid Avenue Campus Box 8057 St, Louis, MO, 63110, USA.
Babak MahmoudiWallace H. Coulter Department of Biomedical Engineering at Georgia Institute of Technology and Emory University, 313 Ferst Dr NW, Atlanta, 30332, GA, USA; Department of Biomedical Informatics at Emory University, 100 Woodruff Circle, Atlanta, GA, 30322, USA. Electronic address: b.mahmoudi@emory.edu.

Funding

Mapping and Modulating the Spatiotemporal dynamics of socio-affective processing.R01MH127006 · NIMH · BAYLOR COLLEGE OF MEDICINE · PI BIJANKI, KELLY ROWE · 2021 to 2025
$3.2M
Asynchronous distributed multielectrode neuromodulation for epilepsyUG3NS100559 · NINDS · EMORY UNIVERSITY · PI DEVERGNAS, ANNAELLE, GROSS, ROBERT E · 2016 to 2020
$2.7M
Mechanisms of Amygdala-Mediated Memory Enhancement in HumansR01MH120194 · NIMH · WASHINGTON UNIVERSITY · PI WILLIE, JON TIMOTHY · 2020 to 2024
$1.8M
A framework for developing translatable intelligent neural interface systems for precision neuromodulation therapiesR01EB028350 · NIBIB · EMORY UNIVERSITY · PI ESMAEILZADEH, HADI, MAHMOUDI, BABAK · 2019 to 2023
$1.6M
NIBIB NIH HHS R01 EB028350NIMH NIH HHS R01 MH120194NIMH NIH HHS R01 MH127006NINDS NIH HHS UG3 NS100559
6 · The paper itself

Abstract

backgroundDirect electrical stimulation of the amygdala can enhance declarative memory for specific events. An unanswered question is what underlying neurophysiological changes are induced by amygdala stimulation.

objectiveTo leverage interpretable machine learning to identify the neurophysiological processes underlying amygdala-mediated memory, and to develop more efficient neuromodulation technologies.

methodPatients with treatment-resistant epilepsy and depth electrodes placed in the hippocampus and amygdala performed a recognition memory task for neutral images of objects. During the encoding phase, 160 images were shown to patients. Half of the images were followed by brief low-amplitude amygdala stimulation. For local field potentials (LFPs) recorded from key medial temporal lobe structures, feature vectors were calculated by taking the average spectral power in canonical frequency bands, before and after stimulation, to train a logistic regression classification model with elastic net regularization to differentiate brain states.

resultsClassifying the neural states at the time of encoding based on images subsequently remembered versus not-remembered showed that theta and slow-gamma power in the hippocampus were the most important features predicting subsequent memory performance. Classifying the post-image neural states at the time of encoding based on stimulated versus unstimulated trials showed that amygdala stimulation led to increased gamma power in the hippocampus.

conclusionAmygdala stimulation induced pro-memory states in the hippocampus to enhance subsequent memory performance. Interpretable machine learning provides an effective tool for investigating the neurophysiological effects of brain stimulation.

Indexed as

Epilepsy, Temporal LobeMemoryAmygdalaHippocampusHumansMachine LearningAmygdala stimulationFeature learningHippocampusInterpretable machine learningLocal field potentialMemoryNeurophysiological biomarkers

Identifiers

PMID34619386
PMCPMC9116878

What OpenQuestion holds

Textmetadata
LicenceTDM
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.