Abstract

Imaging neuronal activity with high and homogeneous spatial resolution across the field-of-view (FOV) and limited invasiveness in deep brain regions is fundamental for the progress of neuroscience, yet is a major technical challenge. We achieved this goal by correcting optical aberrations in gradient index lens-based ultrathin (≤ 500 µm) microendoscopes using aspheric microlenses generated through 3D-microprinting. Corrected microendoscopes had extended FOV (eFOV) with homogeneous spatial resolution for two-photon fluorescence imaging and required no modification of the optical set-up. Synthetic calcium imaging data showed that, compared to uncorrected endoscopes, eFOV-microendoscopes led to improved signal-to-noise ratio and more precise evaluation of correlated neuronal activity. We experimentally validated these predictions in awake head-fixed mice. Moreover, using eFOV-microendoscopes we demonstrated cell-specific encoding of behavioral state-dependent information in distributed functional subnetworks in a primary somatosensory thalamic nucleus. eFOV-microendoscopes are, therefore, small-cross-section ready-to-use tools for deep two-photon functional imaging with unprecedentedly high and homogeneous spatial resolution.

Data availability

The datasets shown in Figures 4, 6, 7 and corresponding figure supplements are available at:https://data.mendeley.com/datasets/wm6c5wzs4c/draft?a=56f1660e-a036-40ee-83ef-458dc2457b6aThe software used in this paper to generate and analyze artificial t-series is available at: https://github.com/moni90/eFOV_microendoscopes_simNumerical data for graphs represented in figures 3-7, figure 2-figure supplement 2-4, figure 3-figure supplement 4, figure 4-figure supplement 1-2 are provided as source data.

The following data sets were generated

Article and author information

Author details

  1. Andrea Antonini

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  2. Andrea Sattin

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  3. Monica Moroni

    CNCS, Italian Institute of Technology, ROVERETO, Italy
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1852-7217
  4. Serena Bovetti

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  5. Claudio Moretti

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  6. Francesca Succol

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  7. Angelo Forli

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  8. Dania Vecchia

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    Competing interests
    The authors declare that no competing interests exist.
  9. Vijayakumar P Rajamanickam

    BESE, KAUST, Thuwal, Saudi Arabia
    Competing interests
    The authors declare that no competing interests exist.
  10. Andrea Bertoncini

    BESE, KAUST, Thuwal, Saudi Arabia
    Competing interests
    The authors declare that no competing interests exist.
  11. Stefano Panzeri

    Center for Neuroscience and Cognitive Systems, Italian Institute of Technology, Rovereto, Italy
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1700-8909
  12. Carlo Liberale

    BESE, KAUST, Thuwal, Saudi Arabia
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5653-199X
  13. Tommaso Fellin

    Department of Neuroscience and Brain Technologies, Italian Institute of Technology, Genova, Italy
    For correspondence
    tommaso.fellin@iit.it
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2718-7533

Funding

European Research Council (NEURO-PATTERNS)

  • Tommaso Fellin

IIT interdisciplinary grant

  • Tommaso Fellin

IIT interdisciplinary grant

  • Carlo Liberale

KAUST (BAS/1/1064-01-01)

  • Carlo Liberale

NIH Brain Initiative (NS090576)

  • Tommaso Fellin

NIH Brain Initiative (NS107464)

  • Tommaso Fellin

NIH Brain Initiative (NS107464)

  • Stefano Panzeri

NIH Brain Initiative (NS109961)

  • Stefano Panzeri

FP7 (DESIRE)

  • Tommaso Fellin

FIRB (RBAP11X42L)

  • Tommaso Fellin

Flag-Era JTC Human Brain Project (SLOW-DYN)

  • Tommaso Fellin

Flag-Era JTC Human Brain Project (SLOW-DYN)

  • Stefano Panzeri

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

Reviewing Editor

  1. Ryohei Yasuda, Max Planck Florida Institute for Neuroscience, United States

Ethics

Animal experimentation: Experimental procedures involving animals have been approved by the Istituto Italiano di Tecnologia Animal Health Regulatory Committee, by the National Council on Animal Care of the Italian Ministry of Health (authorization # 1134/2015-PR, # 689/2018-PR) and carried out according to the National legislation (D.Lgs. 26/2014) and to the legislation of the European Communities Council Directive (European Directive 2010/63/EU).

Version history

  1. Received: May 13, 2020
  2. Accepted: October 12, 2020
  3. Accepted Manuscript published: October 13, 2020 (version 1)
  4. Accepted Manuscript updated: October 15, 2020 (version 2)
  5. Version of Record published: November 24, 2020 (version 3)

Copyright

© 2020, Antonini et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

Metrics

  • 3,444
    Page views
  • 566
    Downloads
  • 29
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

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. Andrea Antonini
  2. Andrea Sattin
  3. Monica Moroni
  4. Serena Bovetti
  5. Claudio Moretti
  6. Francesca Succol
  7. Angelo Forli
  8. Dania Vecchia
  9. Vijayakumar P Rajamanickam
  10. Andrea Bertoncini
  11. Stefano Panzeri
  12. Carlo Liberale
  13. Tommaso Fellin
(2020)
Extended field-of-view ultrathin microendoscopes for high-resolution two-photon imaging with minimal invasiveness
eLife 9:e58882.
https://doi.org/10.7554/eLife.58882

Share this article

https://doi.org/10.7554/eLife.58882

Further reading

    1. Neuroscience
    Kiwamu Kudo, Kamalini G Ranasinghe ... Srikantan S Nagarajan
    Research Article

    Alzheimer’s disease (AD) is characterized by the accumulation of amyloid-β and misfolded tau proteins causing synaptic dysfunction, and progressive neurodegeneration and cognitive decline. Altered neural oscillations have been consistently demonstrated in AD. However, the trajectories of abnormal neural oscillations in AD progression and their relationship to neurodegeneration and cognitive decline are unknown. Here, we deployed robust event-based sequencing models (EBMs) to investigate the trajectories of long-range and local neural synchrony across AD stages, estimated from resting-state magnetoencephalography. The increases in neural synchrony in the delta-theta band and the decreases in the alpha and beta bands showed progressive changes throughout the stages of the EBM. Decreases in alpha and beta band synchrony preceded both neurodegeneration and cognitive decline, indicating that frequency-specific neuronal synchrony abnormalities are early manifestations of AD pathophysiology. The long-range synchrony effects were greater than the local synchrony, indicating a greater sensitivity of connectivity metrics involving multiple regions of the brain. These results demonstrate the evolution of functional neuronal deficits along the sequence of AD progression.

    1. Medicine
    2. Neuroscience
    Luisa Fassi, Shachar Hochman ... Roi Cohen Kadosh
    Research Article

    In recent years, there has been debate about the effectiveness of treatments from different fields, such as neurostimulation, neurofeedback, brain training, and pharmacotherapy. This debate has been fuelled by contradictory and nuanced experimental findings. Notably, the effectiveness of a given treatment is commonly evaluated by comparing the effect of the active treatment versus the placebo on human health and/or behaviour. However, this approach neglects the individual’s subjective experience of the type of treatment she or he received in establishing treatment efficacy. Here, we show that individual differences in subjective treatment - the thought of receiving the active or placebo condition during an experiment - can explain variability in outcomes better than the actual treatment. We analysed four independent datasets (N = 387 participants), including clinical patients and healthy adults from different age groups who were exposed to different neurostimulation treatments (transcranial magnetic stimulation: Studies 1 and 2; transcranial direct current stimulation: Studies 3 and 4). Our findings show that the inclusion of subjective treatment can provide a better model fit either alone or in interaction with objective treatment (defined as the condition to which participants are assigned in the experiment). These results demonstrate the significant contribution of subjective experience in explaining the variability of clinical, cognitive, and behavioural outcomes. We advocate for existing and future studies in clinical and non-clinical research to start accounting for participants’ subjective beliefs and their interplay with objective treatment when assessing the efficacy of treatments. This approach will be crucial in providing a more accurate estimation of the treatment effect and its source, allowing the development of effective and reproducible interventions.