Source 1review2017Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences
Toolkit/Scanning photo-induced impedance microscopy
Scanning photo-induced impedance microscopy
Also known as: Scanning photoinduced impedance microscopy, SPIM
Taxonomy: Technique Branch / Method. Workflows sit above the mechanism and technique branches rather than replacing them.
Summary
Light-addressable potentiometric sensors (LAPS) and scanning photo-induced impedance microscopy (SPIM) use photocurrent measurements at electrolyte-insulator-semiconductor substrates for spatio-temporal imaging of electrical potentials and impedance.
Usefulness & Problems
Why this is useful
SPIM is described in the upstream source summary as the imaging modality used in the study's whole-brain mapping pipeline.; whole-brain imaging in phenotyping workflows; SPIM uses photocurrent measurements on electrolyte-insulator-semiconductor substrates to image impedance with spatial and temporal resolution. The abstract places it alongside LAPS as a core modality for biological imaging.; spatio-temporal imaging of impedance; imaging biological systems; lateral imaging of cell surface charges; imaging cell metabolism
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SPIM is described in the upstream source summary as the imaging modality used in the study's whole-brain mapping pipeline.
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whole-brain imaging in phenotyping workflows
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SPIM uses photocurrent measurements on electrolyte-insulator-semiconductor substrates to image impedance with spatial and temporal resolution. The abstract places it alongside LAPS as a core modality for biological imaging.
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spatio-temporal imaging of impedance
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imaging biological systems
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lateral imaging of cell surface charges
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imaging cell metabolism
Problem solved
It provides whole-brain imaging needed for large-scale mapping of activated neuronal ensembles.; enables imaging for brain-wide cellular mapping; It enables spatial imaging of impedance-related properties in biological systems, including cell surface charge and metabolism-associated signals. This provides label-free electrical contrast rather than conventional optical labels.; provides spatially resolved impedance imaging for biological systems
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It provides whole-brain imaging needed for large-scale mapping of activated neuronal ensembles.
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enables imaging for brain-wide cellular mapping
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It enables spatial imaging of impedance-related properties in biological systems, including cell surface charge and metabolism-associated signals. This provides label-free electrical contrast rather than conventional optical labels.
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provides spatially resolved impedance imaging for biological systems
Problem links
enables imaging for brain-wide cellular mapping
LiteratureIt provides whole-brain imaging needed for large-scale mapping of activated neuronal ensembles.
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It provides whole-brain imaging needed for large-scale mapping of activated neuronal ensembles.
provides spatially resolved impedance imaging for biological systems
LiteratureIt enables spatial imaging of impedance-related properties in biological systems, including cell surface charge and metabolism-associated signals. This provides label-free electrical contrast rather than conventional optical labels.
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It enables spatial imaging of impedance-related properties in biological systems, including cell surface charge and metabolism-associated signals. This provides label-free electrical contrast rather than conventional optical labels.
Published Workflows
Objective: Map a distributed engram complex for contextual fear conditioning memory across the mouse brain and test whether distributed engram ensembles are functionally connected and jointly contribute to memory recall.
Why it works: The workflow combines brain-wide phenotyping to identify candidate engram-containing regions with causal perturbation experiments to test whether those ensembles are functionally connected and contribute to recall.
distributed storage of a single memory across multiple functionally connected brain regionsreactivation of neuronal ensembles during recalltissue phenotypingengram index prioritizationoptogenetic manipulationchemogenetic reactivation
Stages
- 1.Brain-wide tissue phenotyping(broad_screen)
This stage provides a brain-wide map and narrows many assayed regions to a smaller set of candidate engram regions.
Selection: encoding activated neuronal ensembles characterized across regions and prioritized with an engram index
- 2.Recall reactivation assessment(secondary_characterization)
This stage adds evidence that candidate ensembles are reactivated during recall rather than only during encoding.
Selection: brain-wide reactivation of candidate neuronal ensembles by recall
- 3.Optogenetic functional interrogation(functional_characterization)
This stage tests whether mapped candidate ensembles are functionally connected to known hippocampal or amygdala engrams.
Selection: optogenetic manipulation to reveal engram ensembles and their functional connections
- 4.Chemogenetic multi-ensemble recall test(confirmatory_validation)
This stage tests whether coordinated reactivation of multiple engram ensembles better reflects natural recall than reactivation of a single ensemble.
Selection: comparison of memory recall after simultaneous multi-ensemble versus single-ensemble chemogenetic reactivation
Taxonomy & Function
Primary hierarchy
Technique Branch
Method: A concrete measurement method used to characterize an engineered system.
Techniques
Functional AssayTarget processes
No target processes tagged yet.
Input: Light
Implementation Constraints
cofactor dependency: cofactor requirement unknownencoding mode: genetically encodedimplementation constraint: context specific validationimplementation constraint: spectral hardware requirementoperating role: sensor
It requires prepared brain tissue and downstream segmentation or activated-cell detection analysis.; requires processed whole-brain tissue; The method requires electrolyte-insulator-semiconductor substrates and photocurrent-based instrumentation. A scanning optical addressing setup is implied by the method name and abstract framing.; requires photocurrent measurement; requires electrolyte-insulator-semiconductor substrates
the abstract does not specify the exact SPIM implementation or performance metrics; The abstract does not claim that SPIM provides direct molecular identification or that it outperforms all other imaging methods. It also does not specify exact spatial or temporal resolution values.; the abstract does not specify exact implementation tradeoffs or performance boundaries
Validation
Cell-freeBacteriaMammalianMouseHumanTherapeuticIndep. Replication
Supporting Sources
Ranked Claims
Applications described for these techniques include detection of ions, label-free detection of charged molecules such as DNA and proteins, and enzyme-based biosensors.
LAPS and SPIM have been used for interrogation of sensor arrays and imaging of biological systems.
Imaging applications described in the review include temporal imaging of extracellular potentials, dynamic concentration changes in microfluidic channels, and lateral imaging of cell surface charges and cell metabolism.
LAPS and SPIM use photocurrent measurements at electrolyte-insulator-semiconductor substrates for spatio-temporal imaging of electrical potentials and impedance.
Approval Evidence
2 sources4 linked approval claimsfirst-pass slugs scanning-photo-induced-impedance-microscopy, spim
PubMed entry confirms PMCID PMC8980018 and describes the study’s core components including SHIELD processing, SPIM imaging, automatic segmentation, and activated-cell detection.
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Light-addressable potentiometric sensors (LAPS) and scanning photo-induced impedance microscopy (SPIM) use photocurrent measurements at electrolyte-insulator-semiconductor substrates for spatio-temporal imaging of electrical potentials and impedance.
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application scopesupports
Applications described for these techniques include detection of ions, label-free detection of charged molecules such as DNA and proteins, and enzyme-based biosensors.
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application scopesupports
LAPS and SPIM have been used for interrogation of sensor arrays and imaging of biological systems.
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biological imaging scopesupports
Imaging applications described in the review include temporal imaging of extracellular potentials, dynamic concentration changes in microfluidic channels, and lateral imaging of cell surface charges and cell metabolism.
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review scope summarysupports
LAPS and SPIM use photocurrent measurements at electrolyte-insulator-semiconductor substrates for spatio-temporal imaging of electrical potentials and impedance.
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Comparisons
Source-stated alternatives
The review discusses SPIM together with LAPS as a related measurement family. The abstract does not name additional alternative imaging modalities.
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The review discusses SPIM together with LAPS as a related measurement family. The abstract does not name additional alternative imaging modalities.
Source-backed strengths
supports whole-brain mapping workflow; supports spatio-temporal imaging; targets impedance-related contrast in biological samples
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supports whole-brain mapping workflow
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supports spatio-temporal imaging
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targets impedance-related contrast in biological samples
Compared with imaging
The review discusses SPIM together with LAPS as a related measurement family. The abstract does not name additional alternative imaging modalities.
Shared frame: source-stated alternative in extracted literature
Strengths here: supports whole-brain mapping workflow; supports spatio-temporal imaging; targets impedance-related contrast in biological samples.
Relative tradeoffs: the abstract does not specify the exact SPIM implementation or performance metrics; the abstract does not specify exact implementation tradeoffs or performance boundaries.
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The review discusses SPIM together with LAPS as a related measurement family. The abstract does not name additional alternative imaging modalities.
Compared with imaging surveillance
The review discusses SPIM together with LAPS as a related measurement family. The abstract does not name additional alternative imaging modalities.
Shared frame: source-stated alternative in extracted literature
Strengths here: supports whole-brain mapping workflow; supports spatio-temporal imaging; targets impedance-related contrast in biological samples.
Relative tradeoffs: the abstract does not specify the exact SPIM implementation or performance metrics; the abstract does not specify exact implementation tradeoffs or performance boundaries.
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The review discusses SPIM together with LAPS as a related measurement family. The abstract does not name additional alternative imaging modalities.
Compared with Light-addressable potentiometric sensor
The review discusses SPIM together with LAPS as a related measurement family. The abstract does not name additional alternative imaging modalities.
Shared frame: source-stated alternative in extracted literature
Strengths here: supports whole-brain mapping workflow; supports spatio-temporal imaging; targets impedance-related contrast in biological samples.
Relative tradeoffs: the abstract does not specify the exact SPIM implementation or performance metrics; the abstract does not specify exact implementation tradeoffs or performance boundaries.
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The review discusses SPIM together with LAPS as a related measurement family. The abstract does not name additional alternative imaging modalities.
Ranked Citations
- 1.