Abstract
Despite the growing popularity of blood oxygen level–dependent (BOLD) functional MRI (fMRI), understanding of its underlying principles is still limited. This protocol describes a technique for simultaneous measurement of neural activity using fluorescent calcium indicators together with the corresponding hemodynamic BOLD fMRI response in the mouse brain. Our early work using small-molecule fluorophores in rats gave encouraging results but was limited to acute measurements using synthetic dyes. Our latest procedure combines fMRI with optical detection of cell-type-specific virally delivered GCaMP6, a genetically encoded calcium indicator (GECI). GCaMP6 fluorescence, which increases upon calcium binding, is collected by a chronically implanted optical fiber, allowing longitudinal studies in mice. The chronic implant, placed horizontally on the skull, has an angulated tip that reflects light into the brain and is connected via fiber optics to a remote optical setup. The technique allows access to the neocortex and does not require adaptations of commercial MRI hardware. The hybrid approach permits fiber-optic calcium recordings with simultaneous artifact-free BOLD fMRI with full brain coverage and 1-s temporal resolution using standard gradient-echo echo-planar imaging (GE-EPI) sequences. The method provides robust, cell-type-specific readouts to link neural activity to BOLD signals, as emonstrated for task-free ('resting-state') conditions and in response to hind-paw stimulation. These results highlight the power of fiber photometry combined with fMRI, which we aim to further advance in this protocol. The approach can be easily adapted to study other molecular processes using suitable fluorescent indicators.
This is a preview of subscription content, access via your institution
Access options
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Kwong, K.K. et al. Dynamic magnetic resonance imaging of human brain activity during primary sensory stimulation. Proc. Natl. Acad. Sci. USA 89, 5675–5679 (1992).
Ogawa, S. et al. Intrinsic signal changes accompanying sensory stimulation: functional brain mapping with magnetic resonance imaging. Proc. Natl. Acad. Sci. USA 89, 5951–5955 (1992).
Huster, R.J., Debener, S., Eichele, T. & Herrmann, C.S. Methods for simultaneous EEG-fMRI: an introductory review. J. Neurosci. 32, 6053–6060 (2012).
Steinbrink, J. et al. Illuminating the BOLD signal: combined fMRI–fNIRS studies. Magn. Reson. Imaging 24, 495–505 (2006).
Hillman, E.M.C. Coupling mechanism and significance of the BOLD signal: a status report. Annu. Rev. Neurosci. 37, 161–181 (2014).
Ives, J.R., Warach, S., Schmitt, F., Edelman, R.R. & Schomer, D.L. Monitoring the patient’s EEG during echo planar MRI. Electroencephalogr. Clin. Neurophysiol. 87, 417–420 (1993).
Oishi, N. et al. Neural correlates of regional EEG power change. Neuroimage 36, 1301–1312 (2007).
Brinker, G. et al. Simultaneous recording of evoked potentials and T2*-weighted MR images during somatosensory stimulation of rat. Magn. Reson. Med. 41, 469–473 (1999).
Logothetis, N.K., Pauls, J., Augath, M., Trinath, T. & Oeltermann, A. Neurophysiological investigation of the basis of the fMRI signal. Nature 412, 150–157 (2001).
Goense, J.B.M. & Logothetis, N.K. Neurophysiology of the BOLD fMRI signal in awake monkeys. Curr. Biol. 18, 631–640 (2008).
Scanziani, M. & Häusser, M. Electrophysiology in the age of light. Nature 461, 930–939 (2009).
Rose, T., Goltstein, P.M., Portugues, R. & Griesbeck, O. Putting a finishing touch on GECIs. Front. Mol. Neurosci. 7, 88 (2014).
Tian, L., Hires, S.A. & Looger, L.L. Imaging neuronal activity with genetically encoded calcium indicators. Cold Spring Harb. Protoc. 2012, 647–656 (2012).
Yang, W. & Yuste, R. In vivo imaging of neural activity. Nat. Methods 14, 349–359 (2017).
Murphy, T.H. et al. High-throughput automated home-cage mesoscopic functional imaging of mouse cortex. Nat. Commun. 7, 11611 (2016).
Adelsberger, H., Grienberger, C., Stroh, A. & Konnerth, A. In vivo calcium recordings and channelrhodopsin-2 activation through an optical fiber. Cold Spring Harb. Protoc. 2014, pdb.prot084145 (2014).
Guo, Q. et al. Multi-channel fiber photometry for population neuronal activity recording. Biomed. Opt. Express 6, 3919 (2015).
Murayama, M., Perez-Garci, E., Luscher, H.-R. & Larkum, M.E. Fiberoptic system for recording dendritic calcium signals in layer 5 neocortical pyramidal cells in freely moving rats. J. Neurophysiol. 98, 1791–1805 (2007).
Lütcke, H. et al. Optical recording of neuronal activity with a genetically-encoded calcium indicator in anesthetized and freely moving mice. Front. Neural Circuits 4, 9 (2010).
Stroh, A. et al. Making waves: initiation and propagation of corticothalamic Ca2+ waves in vivo. Neuron 77, 1136–1150 (2013).
Cui, G. et al. Concurrent activation of striatal direct and indirect pathways during action initiation. Nature 494, 238–242 (2013).
Fuhrmann, F. et al. Locomotion, theta oscillations, and the speed-correlated firing of hippocampal neurons are controlled by a medial septal glutamatergic circuit. Neuron 86, 1253–1264 (2015).
Cui, G. et al. Deep brain optical measurements of cell type-specific neural activity in behaving mice. Nat. Protoc. 9, 1213–1228 (2014).
González, J.A., Iordanidou, P., Strom, M., Adamantidis, A. & Burdakov, D. Awake dynamics and brain-wide direct inputs of hypothalamic MCH and orexin networks. Nat. Commun. 7, 11395 (2016).
Schulz, K. et al. Simultaneous BOLD fMRI and fiber-optic calcium recording in rat neocortex. Nat. Methods 9, 597–602 (2012).
Lee, J.H. et al. Global and local fMRI signals driven by neurons defined optogenetically by type and wiring. Nature 465, 788–792 (2010).
Scherf, T. et al. Hippocampal CA3 activation alleviates fMRI-BOLD responses in the rat prefrontal cortex induced by electrical VTA stimulation. PLoS One 12, e0172926 (2017).
Lohani, S., Poplawsky, A.J., Kim, S.-G. & Moghaddam, B. Unexpected global impact of VTA dopamine neuron activation as measured by opto-fMRI. Mol. Psychiatry 22, 585–594 (2017).
Kahn, I. et al. Characterization of the functional MRI response temporal linearity via optical control of neocortical pyramidal neurons. J. Neurosci. 31, 15086–15091 (2011).
Christie, I.N., Wells, J.A., Kasparov, S., Gourine, A.V. & Lythgoe, M.F. Volumetric spatial correlations of neurovascular coupling studied using single pulse opto-fMRI. Sci. Rep. 7, 41583 (2017).
Schmid, F. et al. Assessing sensory versus optogenetic network activation by combining (o)fMRI with optical Ca2+ recordings. J. Cereb. Blood Flow Metab. 36, 1885–1900 (2016).
Rungta, R.L., Osmanski, B.-F., Boido, D., Tanter, M. & Charpak, S. Light controls cerebral blood flow in naive animals. Nat. Commun. 8, 14191 (2017).
Shigetomi, E. et al. Imaging calcium microdomains within entire astrocyte territories and endfeet with GCaMPs expressed using adeno-associated viruses. J. Gen. Physiol. 141, 633–647 (2013).
Nakai, J., Ohkura, M. & Imoto, K. A high signal-to-noise Ca2+ probe composed of a single green fluorescent protein. Nat. Biotechnol. 19, 137–141 (2001).
Chen, T.-W. et al. Ultrasensitive fluorescent proteins for imaging neuronal activity. Nature 499, 295–300 (2013).
Tsien, R.Y. et al. Fluorescent indicators for Ca2+ based on green fluorescent proteins and calmodulin. Nature 388, 882–887 (1997).
Nagai, T., Yamada, S., Tominaga, T., Ichikawa, M. & Miyawaki, A. Expanded dynamic range of fluorescent indicators for Ca2+ by circularly permuted yellow fluorescent proteins. Proc. Natl. Acad. Sci. USA 101, 10554–10559 (2004).
Horikawa, K. et al. Spontaneous network activity visualized by ultrasensitive Ca2+ indicators, yellow Cameleon-Nano. Nat. Methods 7, 729–732 (2010).
Dana, H. et al. Sensitive red protein calcium indicators for imaging neural activity. Elife 5, 1888–1891 (2016).
Srinivasan, R. et al. Ca2+ signaling in astrocytes from Ip3r2/ mice in brain slices and during startle responses in vivo. Nat. Neurosci. 18, 708–717 (2015).
Margolis, D.J. et al. Reorganization of cortical population activity imaged throughout long-term sensory deprivation. Nat. Neurosci. 15, 1539–1546 (2012).
Stobart, J.L. et al. Long-term in vivo calcium imaging of astrocytes reveals distinct cellular compartment responses to sensory stimulation. Cereb. Cortex 1–15 (2016).
Doronina-Amitonova, L.V. et al. Implantable fiber-optic interface for parallel multisite long-term optical dynamic brain interrogation in freely moving mice. Sci. Rep. 3, 3265 (2013).
Garcia, M.I., Chen, J.J. & Boehning, D. Genetically encoded calcium indicators for studying long-term calcium dynamics during apoptosis. Cell Calcium 61, 44–49 (2017).
Margolis, D.J., Lütcke, H., Helmchen, F., Weber, B. & Haiss, F. in Optical Imaging of Neocortical Dynamics (eds. Weber, B. & Helmchen, F.) 151–173 Humana Press, 2014.
Pan, W. et al. Simultaneous FMRI and electrophysiology in the rodent brain. J. Vis. Exp. http://dx.doi.org/10.3791/1901 (2010).
Oeltermann, A., Augath, M.A. & Logothetis, N.K. Simultaneous recording of neuronal signals and functional NMR imaging. Magn. Reson. Imaging 25, 760–774 (2007).
Kim, C.K. et al. Simultaneous fast measurement of circuit dynamics at multiple sites across the mammalian brain. Nat. Methods 13, 325–328 (2016).
Ren, W. et al. Dynamic measurement of tumor vascular permeability and perfusion using a hybrid system for simultaneous magnetic resonance and fluorescence imaging. Mol. Imaging Biol. 18, 191–200 (2016).
Murayama, M. & Larkum, M.E. In vivo dendritic calcium imaging with a fiberoptic periscope system. Nat. Protoc. 4, 1551–1559 (2009).
Inagaki, S. & Nagai, T. Current progress in genetically encoded voltage indicators for neural activity recording. Curr. Opin. Chem. Biol. 33, 95–100 (2016).
Potzkei, J. et al. Real-time determination of intracellular oxygen in bacteria using a genetically encoded FRET-based biosensor. BMC Biol. 10, 28 (2012).
Tantama, M., Hung, Y.P. & Yellen, G. Imaging intracellular pH in live cells with a genetically encoded red fluorescent protein sensor. J. Am. Chem. Soc. 133, 10034–10037 (2011).
Kuner, T. & Augustine, G.J. A genetically encoded ratiometric indicator for chloride: capturing chloride transients in cultured hippocampal neurons. Neuron 27, 447–459 (2000).
Deuschle, K. et al. Construction and optimization of a family of genetically encoded metabolite sensors by semirational protein engineering. Protein Sci. 14, 2304–2314 (2005).
San Martín, A. et al. A genetically encoded FRET lactate sensor and its use to detect the Warburg effect in single cancer cells. PLoS One 8, e57712 (2013).
Mächler, P. et al. In vivo evidence for a lactate gradient from astrocytes to neurons. Cell Metab. 23, 94–102 (2016).
Violin, J.D., Zhang, J., Tsien, R.Y. & Newton, A.C. A genetically encoded fluorescent reporter reveals oscillatory phosphorylation by protein kinase C. J. Cell Biol. 161, 899–909 (2003).
Roth, B.L. DREADDs for neuroscientists. Neuron 89, 683–694 (2016).
Zhang, F., Wang, L.-P., Boyden, E.S. & Deisseroth, K. Channelrhodopsin-2 and optical control of excitable cells. Nat. Methods 3, 785–792 (2006).
Zeng, H. & Madisen, L. Mouse transgenic approaches in optogenetics. Prog. Brain Res. 196, 193–213 (2012).
Dana, H. et al. Thy1-GCaMP6 transgenic mice for neuronal population imaging in vivo. PLoS One 9, e108697 (2014).
Desai, M. et al. Mapping brain networks in awake mice using combined optical neural control and fMRI. J. Neurophysiol. 105, 1393–1405 (2011).
Gao, Y.-R. et al. Time to wake up: studying neurovascular coupling and brain-wide circuit function in the un-anesthetized animal. Neuroimage 153, 382–398 (2016).
Akerboom, J. et al. Optimization of a GCaMP calcium indicator for neural activity imaging. J. Neurosci. 32, 13819–13840 (2012).
Madisen, L. et al. Transgenic mice for intersectional targeting of neural sensors and effectors with high specificity and performance. Neuron 85, 942–958 (2015).
Srinivasan, R. et al. New transgenic mouse lines for selectively targeting astrocytes and studying calcium signals in astrocyte processes in situ and in vivo. Neuron 92, 1181–1195 (2016).
Harris, J.A. et al. Anatomical characterization of Cre driver mice for neural circuit mapping and manipulation. Front. Neural Circuits 8, 76 (2014).
Holtmaat, A. et al. Long-term, high-resolution imaging in the mouse neocortex through a chronic cranial window. Nat. Protoc. 4, 1128–1144 (2009).
Baltes, C., Radzwill, N., Bosshard, S., Marek, D. & Rudin, M. Micro MRI of the mouse brain using a novel 400MHz cryogenic quadrature RF probe. NMR Biomed. 22, 834–842 (2009).
Hanusch, C., Hoeger, S. & Beck, G.C. Anaesthesia of small rodents during magnetic resonance imaging. Methods 43, 68–78 (2007).
Ueki, M., Mies, G. & Hossmann, K.A. Effect of alpha-chloralose, halothane, pentobarbital and nitrous oxide anesthesia on metabolic coupling in somatosensory cortex of rat. Acta Anaesthesiol. Scand. 36, 318–322 (1992).
Soma, L.R. Anesthetic and analgesic considerations in the experimental animal. Ann. N. Y. Acad. Sci. 32–47 (1983).
Zerbi, V., Grandjean, J., Rudin, M. & Wenderoth, N. Mapping the mouse brain with rs-fMRI: an optimized pipeline for functional network identification. Neuroimage 123, 11–21 (2015).
Grandjean, J., Schroeter, A., Batata, I. & Rudin, M. Optimization of anesthesia protocol for resting-state fMRI in mice based on differential effects of anesthetics on functional connectivity patterns. Neuroimage 102, 838–847 (2014).
Lerner, T.N. et al. Intact-brain analyses reveal distinct information carried by SNc dopamine subcircuits. Cell 162, 635–647 (2015).
Zhao, F. BOLD study of stimulation-induced neural activity and resting-state connectivity in medetomidine-sedated rat. Neuroimage 39, 248–260 (2009).
Bosshard, S.C. et al. Assessment of brain responses to innocuous and noxious electrical forepaw stimulation in mice using BOLD fMRI. Pain 151, 655–663 (2010).
Adamczak, J.M., Farr, T.D., Seehafer, J.U., Kalthoff, D. & Hoehn, M. High field BOLD response to forepaw stimulation in the mouse. Neuroimage 51, 704–712 (2010).
Schroeter, A., Schlegel, F., Seuwen, A., Grandjean, J. & Rudin, M. Specificity of stimulus-evoked fMRI responses in the mouse: the influence of systemic physiological changes associated with innocuous stimulation under four different anesthetics. Neuroimage 94, 372–384 (2014).
Schlegel, F., Schroeter, A. & Rudin, M. The hemodynamic response to somatosensory stimulation in mice depends on the anesthetic used: implications on analysis of mouse fMRI data. Neuroimage 116, 40–49 (2015).
Yu, X. et al. Direct imaging of macrovascular and microvascular contributions to BOLD fMRI in layers IV-V of the rat whisker-barrel cortex. Neuroimage 59, 1451–1460 (2012).
Van Camp, N., Verhoye, M., De Zeeuw, C.I. & Van der Linden, A. Light stimulus frequency dependence of activity in the rat visual system as studied with high-resolution BOLD fMRI. J. Neurophysiol. 95, 3164–3170 (2006).
Jia, H., Rochefort, N.L., Chen, X. & Konnerth, A. In vivo two-photon imaging of sensory-evoked dendritic calcium signals in cortical neurons. Nat. Protoc. 6, 28–35 (2011).
Monti, M.M. Statistical analysis of fMRI time-series: a critical review of the GLM approach. Front. Hum. Neurosci. 5, 28 (2011).
Albers, F., Schmid, F., Wachsmuth, L. & Faber, C. Line scanning fMRI reveals earlier onset of optogenetically evoked BOLD response in rat somatosensory cortex as compared to sensory stimulation. Neuroimage 164, 144–154 (2018).
Yu, X., Qian, C., Chen, D.-Y., Dodd, S.J. & Koretsky, A.P. Deciphering laminar-specific neural inputs with line-scanning fMRI. Nat. Methods 11, 55–58 (2013).
Glover, C.P.J., Bienemann, A.S., Heywood, D.J., Cosgrave, A.S. & Uney, J.B. Adenoviral-mediated, high-level, cell-specific transgene expression: a SYN1-WPRE cassette mediates increased transgene expression with no loss of neuron specificity. Mol. Ther. 5, 509–516 (2002).
Kügler, S. et al. Neuron-specific expression of therapeutic proteins: evaluation of different cellular promoters in recombinant adenoviral vectors. Mol. Cell. Neurosci. 17, 78–96 (2001).
Lee, Y., Messing, A., Su, M. & Brenner, M. GFAP promoter elements required for region-specific and astrocyte-specific expression. Glia 56, 481–493 (2008).
Lowery, R.L. & Majewska, A.K. Intracranial injection of adeno-associated viral vectors. J. Vis. Exp. http://dx.doi.org/10.3791/2140 (2010).
Cetin, A., Komai, S., Eliava, M., Seeburg, P.H. & Osten, P. Stereotaxic gene delivery in the rodent brain. Nat. Protoc. 1, 3166–3173 (2007).
Gonzalez-Castillo, J., Roopchansingh, V., Bandettini, P.A. & Bodurka, J. Physiological noise effects on the flip angle selection in BOLD fMRI. Neuroimage 54, 2764–2778 (2011).
Yizhar, O., Fenno, L., Davidson, T., Mogri, M. & Deisseroth, K. Optogenetics in neural systems. Neuron 71, 9–34 (2011).
Aravanis, A.M. et al. An optical neural interface: in vivo control of rodent motor cortex with integrated fiberoptic and optogenetic technology. J. Neural Eng. 4, S143–S156 (2007).
Paxinos, G. The Mouse Brain in Stereotaxic Coordinates (Gulf Professional Publishing, 2004).
Sparta, D.R. et al. Construction of implantable optical fibers for long-term optogenetic manipulation of neural circuits. Nat. Protoc. 7, 12–23 (2011).
Steriade, M., Nunez, A. & Amzica, F. A novel slow (< 1 Hz) oscillation of neocortical neurons in vivo: depolarizing and hyperpolarizing components. J. Neurosci. 13, 3252–3265 (1993).
Landsness, E.C. et al. Sleep-dependent improvement in visuomotor learning: a causal role for slow waves. Sleep 32, 1273–1284 (2009).
Ma, Y. et al. Resting-state hemodynamics are spatiotemporally coupled to synchronized and symmetric neural activity in excitatory neurons. Proc. Natl. Acad. Sci. USA 113, E8463–E8471 (2016).
Matsui, T., Murakami, T. & Ohki, K. Transient neuronal coactivations embedded in globally propagating waves underlie resting-state functional connectivity. Proc. Natl. Acad. Sci. USA 113, 6556–6561 (2016).
Duffy, B.A., Choy, M., Chuapoco, M.R., Madsen, M. & Lee, J.H. MRI compatible optrodes for simultaneous LFP and optogenetic fMRI investigation of seizure-like afterdischarges. Neuroimage 123, 173–184 (2015).
Airaksinen, A.M. et al. Simultaneous fMRI and local field potential measurements during epileptic seizures in medetomidine-sedated rats using raser pulse sequence. Magn. Reson. Med. 64, 1191–1199 (2010).
Shih, Y.-Y.I. et al. Ultra high-resolution fMRI and electrophysiology of the rat primary somatosensory cortex. Neuroimage 73, 113–120 (2013).
Dickey, A.S., Suminski, A., Amit, Y. & Hatsopoulos, N.G. Single-unit stability using chronically implanted multielectrode arrays. J. Neurophysiol. 102, 1331–1339 (2009).
Okun, M. et al. Long term recordings with immobile silicon probes in the mouse cortex. PLoS One 11, e0151180 (2016).
Paralikar, K.J. et al. Feasibility and safety of longitudinal magnetic resonance imaging in a rodent model with intracortical microwire implants. J. Neural Eng. 6, 34001 (2009).
Lütcke, H., Margolis, D.J. & Helmchen, F. Steady or changing? Long-term monitoring of neuronal population activity. Trends Neurosci. 36, 375–384 (2013).
Acknowledgements
This work was supported by an R'Equip grant of the Swiss National Science Foundation (SNSF grant 316030_405019 to F.H. and B.W., grants 310030_141202 and 310030B_160310 to M.R.), a Joint Collaborative Project with F. Hoffmann La-Roche (Y.S. and F.H.) and an ERC Advanced Grant to F.H. (grant 670757; BRAINCOMPATH).
Author information
Authors and Affiliations
Contributions
M.R., F.H., F.S., and Y.S. developed the concept and designed the experiments. F.S. performed the surgeries and experiments with the help of Y.S. and A.S., and prepared the manuscript. F.H. edited the manuscript with contributions from M.R., B.W., A.S., and J.S. Y.S. designed the optical setup and developed the software tools with contributions from F.S. J.S. developed and validated the astrocyte-specific constructs.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Integrated supplementary information
Supplementary Figure 1 Evaluation of the GCaMP6s expression under neuronal or astrocytic promoter.
(a) Photomicrograph of a coronal brain section at the site of primary sensory cortex of a mouse transduced with the neuron specific AAV‐hSyn1‐GCaMP6s. Shown is the GFP channel indicating the area of GCaMP expression. (b) Confocal microscopic section (70 μm thickness) showing a zoomed-in view of a cortical S1 region 2 months after AAV‐hSyn1‐GCaMP6s transduction. The majority of neurons (morphologically discernible as pyramidal neurons with their apical dendrites pointing upwards) show cytosolic GCaMP6s expression and a dark spot (nucleus). Only a small number of neurons appear to show nuclear filling which may indicate toxicity.
(c-e) Show the results of mice transduced with astrocyte‐specific AAV‐GFAP‐GCaMP6s. All scale bars are 20 μm.
(c) Two‐photon microscopic images of GCaMP6s expression (left), the astrocyte‐specific dye sulforhodamine‐101 (20mg/kg, imaged 100 min after i.v. injection, middle), and the overlay of both channels (right). (d) Immunohistochemistry of brain slices at the virus injection site, further stained with anti‐GFP antibody (left), anti-GFAP antibody (middle), and the overlay of both channels (right). (e) Immunohistochemistry to test for microglial activation. As in (d) anti-GFP antibody was applied (left), but anti-Iba1 was used to label microglia (middle). The overlay revealed no overlap between the two channels (right). For further details and additional control experiments of the astrocyte-specific GCaMP6 construct, see Stobart et al.1
1. Stobart, J. L. et al. Long-term in vivo calcium imaging of astrocytes reveals distinct cellular compartment responses to sensory stimulation. Cereb. Cortex 1–15 (2016). doi:10.1093/gbe/evw245
Supplementary Figure 2 Examples of coronal EPI slices for animals with fiber-optic implants, showing varying degrees of susceptibility artifacts.
(a) Representative EPI image in the absence of any artifacts. (b) Small susceptibility artifact caused by air bubbles enclosed in the Kwik-Sil at the fiber implantation site. (c) Strong susceptibility artifact caused by inadequate dental material. Dental materials typically contain paramagnetic particles to render them radiopaque.
Supplementary information
Supplementary Text and Figures
Supplementary Figures 1 and 2, and Supplementary Methods 1–3. (PDF 2611 kb)
Subcutaneous injection.
Demonstrating the injection of the local analgesic subcutaneously under the scalp. (MP4 24579 kb)
Scalp removal.
Demonstrating the procedure and the amount of the scalp that should be removed. (MP4 16192 kb)
Craniotomy.
Demonstrating the use of the microdrill to prepare the craniotomy for the fiber-optic implant. (MP4 16638 kb)
Dental composite wall.
Demonstrating application of the dental composite and the use of the dental curing lamp to create a barrier at the outer circumference of the skull. (MP4 9228 kb)
Connecting the implant.
Demonstrating how the fiber-optic patch cable is connected with a fiber-optic implant via a ceramic split sleeve. (MP4 27985 kb)
Rights and permissions
About this article
Cite this article
Schlegel, F., Sych, Y., Schroeter, A. et al. Fiber-optic implant for simultaneous fluorescence-based calcium recordings and BOLD fMRI in mice. Nat Protoc 13, 840–855 (2018). https://doi.org/10.1038/nprot.2018.003
Published:
Issue Date:
DOI: https://doi.org/10.1038/nprot.2018.003
This article is cited by
-
Moderate white light exposure enhanced spatial memory retrieval by activating a central amygdala-involved circuit in mice
Communications Biology (2023)
-
Emerging imaging methods to study whole-brain function in rodent models
Translational Psychiatry (2021)
-
Multi-scale optoacoustic molecular imaging of brain diseases
European Journal of Nuclear Medicine and Molecular Imaging (2021)
-
Rodent models of post-traumatic stress disorder: behavioral assessment
Translational Psychiatry (2020)
-
Simultaneous cortex-wide fluorescence Ca2+ imaging and whole-brain fMRI
Nature Methods (2020)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.