Differential Recruitment of Interneuron Types by Thalamocortical Input

Across in vitro and in vivo preparations, thalamocortical input consistently recruits FS/PV interneurons preferentially and rapidly, with SOM interneurons receiving weaker direct TC drive. This establishes the FS/PV-mediated feedforward inhibition motif as a robust feature of thalamocortical processing, with a clear temporal hierarchy: FS first, then excitatory neurons, then SOM cells.

{
  "papers": [
    {
      "n": 0,
      "doi": "10.1523/jneurosci.21-08-02699.2001",
      "value": "~60%",
      "method": "cell-attached + whole-cell recording",
      "metric": "fraction of inhibitory neurons firing on TC stimulation",
      "n_analyzed": "",
      "ci_or_error": "",
      "text_access": "abstract_only",
      "n_definition": "cell-attached recordings in barrel cortex",
      "scope_region": "barrel cortex layers IV-V",
      "study_system": "mouse barrel cortex",
      "taxonomic_level": "broad: inhibitory vs excitatory",
      "scope_population": "all inhibitory and excitatory neurons",
      "value_source_sentence": "Thalamocortical stimulation evoked action potentials in ~60% of inhibitory interneurons but in <5% of excitatory neurons.",
      "experimental_conditions": "in vitro, thalamocortical electrical stimulation"
    },
    {
      "n": 0,
      "doi": "10.1016/j.neuron.2009.12.025",
      "value": "robust to FS, weak to SOM",
      "method": "optogenetics + electrophysiology",
      "metric": "TC input strength to FS vs SOM interneurons",
      "n_analyzed": "",
      "ci_or_error": "",
      "text_access": "fulltext",
      "n_definition": "optogenetic TC activation + patch-clamp",
      "scope_region": "somatosensory cortex",
      "study_system": "mouse somatosensory cortex",
      "taxonomic_level": "FS vs SOM interneurons",
      "scope_population": "FS and SOM interneurons",
      "value_source_sentence": "Laser stimulation of ChR2-expressing thalamocortical axons/terminals evoked robust synaptic responses in cortical excitatory cells and fast-spiking (FS) inhibitory interneurons, but only weak responses in somatostatin-containing interneurons.",
      "experimental_conditions": "in vitro, ChR2 optogenetic activation of TC axons"
    },
    {
      "n": 0,
      "doi": "10.1016/j.neuron.2019.07.027",
      "value": "FS first, then E and SST; VIP weak",
      "method": "in vivo electrophysiology",
      "metric": "latency of interneuron type recruitment by touch",
      "n_analyzed": "",
      "ci_or_error": "",
      "text_access": "fulltext",
      "n_definition": "in vivo single unit recordings during behavior",
      "scope_region": "barrel cortex",
      "study_system": "mouse barrel cortex",
      "taxonomic_level": "FS, E, SST, VIP",
      "scope_population": "all four main cell types during active touch",
      "value_source_sentence": "Touch excited fast-spiking (FS) interneurons at short latency, followed by activation of excitatory (E) neurons and somatostatin-expressing (SST) interneurons. Touch only weakly modulated vasoactive intestinal polypeptide-expressing (VIP) interneurons.",
      "experimental_conditions": "in vivo during active whisker-dependent object localization"
    }
  ],
  "comparison_id": "interneuron-recruitment-by-thalamocortical-input",
  "comparison_name": "Differential Recruitment of Interneuron Types by Thalamocortical Input",
  "comparison_type": "convergent evidence",
  "what_it_reveals": "Across in vitro and in vivo preparations, thalamocortical input consistently recruits FS/PV interneurons preferentially and rapidly, with SOM interneurons receiving weaker direct TC drive. This establishes the FS/PV-mediated feedforward inhibition motif as a robust feature of thalamocortical processing, with a clear temporal hierarchy: FS first, then excitatory neurons, then SOM cells.",
  "homogeneity_check": {
    "caveats": [
      "Mix of in vitro and in vivo preparations",
      "Different interneuron classification granularity across studies",
      "First study uses broad inhibitory/excitatory classification while later studies identify specific subtypes"
    ],
    "n_definition_uniform": "false",
    "scope_region_uniform": "true",
    "taxonomic_level_uniform": "false",
    "scope_population_uniform": "false"
  },
  "suggested_plot_type": "timeline"
}

[
  "paper:paper-046e316a15e6",
  "paper:paper-3eb6456daece",
  "paper:e5dc2921-2ba0-4d4f-a34c-67e2b13a356d"
]

{
  "mode": "public_source_pointer_with_short_context",
  "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": "df9fc7e8d455b084152c9d713558dae0013cef21",
  "source_repository_url": "https://github.com/AllenNeuralDynamics/ComputationalReviewPV"
}