Version history

{
  "kind": "infographic",
  "prompt": "Astrocyte Ca2+ responses to locomotion or state transitions span three orders of magnitude in timing: sub-second fast microdomains (Stobart 2018), ~1–2 s population latencies in cortex during locomotion or state switches (Paukert 2014; Bojarskaite 2020), to multi-second flare peaks in Bergmann glia following extended rest (Nimmerjahn 2009). This challenges the textbook claim that astrocyte Ca2+ is uniformly slow and suggests distinct subcellular compartments operate on different timescales.",
  "provider": "other",
  "raw_fields": {
    "papers": [
      {
        "n": 106,
        "doi": "10.1016/j.neuron.2014.04.038",
        "value": "1.4 ± 0.1 s",
        "method": "two-photon in vivo Ca2+ imaging",
        "metric": "onset latency of astrocyte Ca2+ transient after locomotion onset",
        "n_analyzed": "106 locomotion events from 13 mice",
        "ci_or_error": "± 0.1 s SEM",
        "text_access": "fulltext",
        "n_definition": "locomotion events pooled across animals",
        "scope_region": "visual cortex + cerebellum",
        "study_system": "mouse; in vivo two-photon; visual cortex and cerebellum Bergmann glia; awake head-fixed on treadmill",
        "taxonomic_level": "broad class",
        "scope_population": "astrocytes (cortical + Bergmann glia)",
        "value_source_sentence": "In contrast to neuronal activation, which began within 50 ms of locomotion onset, Ca 2+ transients in astrocytes began more than a second later (1.4 ± 0.1 s, n = 106 events from 13 mice), presumably reflecting the additional biochemical steps required to release Ca 2+ from intracellular stores.",
        "experimental_conditions": "voluntary locomotion, darkness; GCaMP3 expressed via GLAST-CreER"
      },
      {
        "n": 93,
        "doi": "10.1016/j.neuron.2009.03.019",
        "value": "4.4 ± 2.5 s",
        "method": "two-photon in vivo Ca2+ imaging with OGB-1 AM",
        "metric": "Ca2+ flare peak latency after locomotion reinitiation",
        "n_analyzed": "93 flare events from 15 mice",
        "ci_or_error": "± 2.5 s SD",
        "text_access": "fulltext",
        "n_definition": "flare events pooled across animals",
        "scope_region": "cerebellar vermis",
        "study_system": "mouse; in vivo two-photon; cerebellar vermis Bergmann glia; awake head-fixed on exercise ball",
        "taxonomic_level": "subtype",
        "scope_population": "Bergmann glia (radial glia)",
        "value_source_sentence": "If >10 s had elapsed since termination of the prior locomotor episode, flares reached peak fluorescence 4.4 ± 2.5 s after reinitiation of movement (n = 93 events, 15 mice) ( Figure 6 C).",
        "experimental_conditions": "voluntary locomotion, following >10 s rest; OGB1-AM bulk loading"
      },
      {
        "n": 0,
        "doi": "10.1016/j.neuron.2018.03.050",
        "value": "588.5 ± 21.2 ms",
        "method": "two-photon in vivo Ca2+ imaging, frame + line-scan",
        "metric": "onset latency of fast astrocyte microdomains (MDs) after sensory stimulus",
        "n_analyzed": "events pooled across animals (n not reported in this sentence)",
        "ci_or_error": "± 21.2 ms SEM",
        "text_access": "fulltext",
        "n_definition": "Ca2+ microdomain events",
        "scope_region": "somatosensory cortex",
        "study_system": "mouse; in vivo two-photon; somatosensory cortex; awake head-fixed",
        "taxonomic_level": "fine compartment",
        "scope_population": "astrocyte fine processes (microdomains)",
        "value_source_sentence": "Fast MDs had a peak onset latency on a similar scale to neurons (mean neuronal onset = 270.7 ± 4.3 ms; mean fast MDs onset = 588.5 ± 21.2 ms; mean delayed MDs onset = 5.45 ± 0.05 s; Figure 2 E).",
        "experimental_conditions": "sensory stimulation; GCaMP6f in astrocytes"
      },
      {
        "n": 0,
        "doi": "10.1038/s41467-020-17062-2",
        "value": "1–2 s before",
        "method": "two-photon + polysomnography",
        "metric": "time astrocyte Ca2+ increase precedes sleep→wake transition",
        "n_analyzed": "NREM→wake (60%) and IS→wake (72%) transitions",
        "ci_or_error": "range 1–2 s",
        "text_access": "fulltext",
        "n_definition": "sleep–wake transition events",
        "scope_region": "somatosensory cortex",
        "study_system": "mouse; in vivo two-photon; somatosensory cortex; head-fixed",
        "taxonomic_level": "broad class",
        "scope_population": "all cortical astrocytes (Lck-GCaMP6f)",
        "value_source_sentence": "We observed a prominent increase in astrocytic Ca 2+ signal frequency 1–2 s before the shift in ECoG, EMG, and mouse movement in 60% of NREM sleep to wakefulness and 72% of IS sleep to wakefulness transitions (Fig.",
        "experimental_conditions": "natural sleep-wake; Lck-GCaMP6f in cortical astrocytes; ECoG + EMG"
      }
    ],
    "comparison_id": "locomotion-ca-timing-across-regions",
    "comparison_name": "Locomotion-evoked astrocyte Ca2+ transient timing across cerebellum and cortex",
    "comparison_type": "cross-study convergent evidence with timescale contrast",
    "what_it_reveals": "Astrocyte Ca2+ responses to locomotion or state transitions span three orders of magnitude in timing: sub-second fast microdomains (Stobart 2018), ~1–2 s population latencies in cortex during locomotion or state switches (Paukert 2014; Bojarskaite 2020), to multi-second flare peaks in Bergmann glia following extended rest (Nimmerjahn 2009). This challenges the textbook claim that astrocyte Ca2+ is uniformly slow and suggests distinct subcellular compartments operate on different timescales.",
    "homogeneity_check": {
      "caveats": [
        "Regions differ: cerebellar Bergmann glia (Nimmerjahn 2009) vs. visual cortex + cerebellum (Paukert 2014) vs. somatosensory cortex (Stobart 2018, Bojarskaite 2020).",
        "Indicator differs: OGB1-AM bulk loading (Nimmerjahn 2009) vs. GCaMP3 (Paukert 2014) vs. GCaMP6f with line scan (Stobart 2018) vs. Lck-GCaMP6f (Bojarskaite 2020) — the progression of sensitivity/kinetics directly affects detectable event classes.",
        "Spatial scale: Paukert/Nimmerjahn report soma/population events; Stobart reports fine-process microdomains; Bojarskaite reports membrane-targeted Lck signals. A whole-cell soma measurement and a process microdomain measurement should not be treated as equivalent observations.",
        "Stimulus differs: spontaneous locomotion (Nimmerjahn, Paukert, Bojarskaite) vs. sensory stimulation triggering fast MDs (Stobart).",
        "The Nimmerjahn n=93 is events pooled across 15 mice; Paukert n=106 from 13 mice; Stobart sentence does not report n for the 588.5 ms value in the source sentence cited; Bojarskaite reports percentages of transitions rather than a pooled n."
      ],
      "n_definition_uniform": "false",
      "scope_region_uniform": "false",
      "taxonomic_level_uniform": "false",
      "scope_population_uniform": "false"
    },
    "suggested_plot_type": "forest plot with log-scale x-axis of latency"
  },
  "section_id": "section_09_evidence_package",
  "source_url": "https://github.com/AllenNeuralDynamics/ComputationalReviewAstrocytes/blob/1a55da0634a3bc04e5688792ed12141ce271d28e/evidence/section_09_evidence_package.json",
  "target_ref": "wiki_page:computationalreviewastrocytes-09",
  "review_repo": "ComputationalReviewAstrocytes",
  "section_ref": "wiki_page:computationalreviewastrocytes-09",
  "source_path": "evidence/section_09_evidence_package.json",
  "source_refs": [
    "paper:paper-1b56aab49663",
    "paper:paper-23d7b31898ec",
    "paper:paper-9a1be146dacd",
    "paper:paper-a94b64d9f47e"
  ],
  "section_title": "In Vivo Astrocyte Dynamics During Behavior",
  "source_policy": {
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    "notes": [
      "Local review repositories are read-only inputs.",
      "SciDEX stores paper metadata, structured evidence, file pointers, and short citation contexts; it does not copy full review prose."
    ],
    "source_commit_sha": "1a55da0634a3bc04e5688792ed12141ce271d28e",
    "source_repository_url": "https://github.com/AllenNeuralDynamics/ComputationalReviewAstrocytes"
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  "review_bundle_ref": "analysis_bundle:ab-029ee9411fe2",
  "origin_url": "https://github.com/AllenNeuralDynamics/ComputationalReviewAstrocytes/blob/1a55da0634a3bc04e5688792ed12141ce271d28e/evidence/section_09_evidence_package.json",
  "commit_sha": "1a55da0634a3bc04e5688792ed12141ce271d28e",
  "created_by": "persona-jerome-lecoq-gbo-neuroscience",
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}