Feedback inhibition and its control in an insect olfactory circuit

  1. Subhasis Ray
  2. Zane N Aldworth
  3. Mark A Stopfer  Is a corresponding author
  1. NIH/NICHD, United States

Abstract

Inhibitory neurons play critical roles in regulating and shaping olfactory responses in vertebrates and invertebrates. In insects, these roles are performed by relatively few neurons, which can be interrogated efficiently, revealing fundamental principles of olfactory coding. Here, with electrophysiological recordings from the locust and a large-scale biophysical model, we analyzed the properties and functions of GGN, a unique giant GABAergic neuron that plays a central role in structuring olfactory codes in the locust mushroom body. Our simulations suggest that depolarization of GGN at its input branch can globally inhibit KCs several hundred microns away. Our in vivo recordings show that GGN responds to odors with complex temporal patterns of depolarization and hyperpolarization that can vary with odors and across animals, leading our model to predict the existence of a yet-undiscovered olfactory pathway. Our analysis reveals basic new features of GGN and the olfactory network surrounding it.

Data availability

Traced neuronal morphology have been deposited on neuromorpho.org and they are currently being processed by the repository. Identical morphology data along with the computational models and simulation scripts are available on GitHub (https://github.com/subhacom/mbnet). Model source code curated in Model DB is available under the accession number 262670.

The following data sets were generated

Article and author information

Author details

  1. Subhasis Ray

    Section on Sensory Coding and Neural Ensembles, NIH/NICHD, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2566-7146
  2. Zane N Aldworth

    Section on Sensory Coding and Neural Ensembles, NIH/NICHD, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Mark A Stopfer

    Section on Sensory Coding and Neural Ensembles, NIH/NICHD, Bethesda, United States
    For correspondence
    stopferm@mail.nih.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9200-1884

Funding

NIH-NICHD (Intramural grant)

  • Subhasis Ray
  • Zane N Aldworth
  • Mark A Stopfer

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

Metrics

  • 2,102
    views
  • 253
    downloads
  • 16
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Subhasis Ray
  2. Zane N Aldworth
  3. Mark A Stopfer
(2020)
Feedback inhibition and its control in an insect olfactory circuit
eLife 9:e53281.
https://doi.org/10.7554/eLife.53281

Share this article

https://doi.org/10.7554/eLife.53281

Further reading

    1. Neuroscience
    Nicolas Langer, Maurice Weber ... Ce Zhang
    Tools and Resources

    Memory deficits are a hallmark of many different neurological and psychiatric conditions. The Rey–Osterrieth complex figure (ROCF) is the state-of-the-art assessment tool for neuropsychologists across the globe to assess the degree of non-verbal visual memory deterioration. To obtain a score, a trained clinician inspects a patient’s ROCF drawing and quantifies deviations from the original figure. This manual procedure is time-consuming, slow and scores vary depending on the clinician’s experience, motivation, and tiredness. Here, we leverage novel deep learning architectures to automatize the rating of memory deficits. For this, we collected more than 20k hand-drawn ROCF drawings from patients with various neurological and psychiatric disorders as well as healthy participants. Unbiased ground truth ROCF scores were obtained from crowdsourced human intelligence. This dataset was used to train and evaluate a multihead convolutional neural network. The model performs highly unbiased as it yielded predictions very close to the ground truth and the error was similarly distributed around zero. The neural network outperforms both online raters and clinicians. The scoring system can reliably identify and accurately score individual figure elements in previously unseen ROCF drawings, which facilitates explainability of the AI-scoring system. To ensure generalizability and clinical utility, the model performance was successfully replicated in a large independent prospective validation study that was pre-registered prior to data collection. Our AI-powered scoring system provides healthcare institutions worldwide with a digital tool to assess objectively, reliably, and time-efficiently the performance in the ROCF test from hand-drawn images.

    1. Neuroscience
    Mohsen Alavash
    Insight

    Combining electrophysiological, anatomical and functional brain maps reveals networks of beta neural activity that align with dopamine uptake.