Dentate Gyrus

2022-04-30: reference:

Dentate Gyrus #

• Part of the hippocampal formation:
• Its principal cells are the Granule Cells (axons called Mossy Fibers, which here are glutamatergic.
• Consists of the outer molecular layer, granule layer, and inner polymorphic layer.
• Neurogenesis in the dentate gyrus: carrying the message or dictating the tone (2013)
  • The majority of DG neurons are under strong inhibition and rarely fire action potentials. Thus it’s odd why there’s neurogenesis.
  • Egr1 activity after spatial exploration:
  • 
• A dentate gyrus-CA3 inhibitory circuit promotes evolution of hippocampal-cortical ensembles during memory consolidation
  • Bonk: TAK-653 activating DG → CA3 overactivity creating more contextual association = the dissociative effect.
  • (DG → CA3) encodes memories, and sends it to → CA1 → Anterior Cingulate Cortex for consolidation.
    • CA1 Parvalbumin inhibitory neurons onto the cortex.
      • ChatGPT says there aren’t just CA1 efferents on the ACC. It goes to the subiculum first.
  • Increasing feedforward inhibition DG → CA3 promoted context specificity of neuronal ensembles in Anterior Cingulate Cortex over time and enhanced long-term contextual fear memory
  • FFI facilitates formation and maintenance of context-associated neuronal ensembles in CA1.
    • A contextual binding theory of episodic memory: Systems consolidation reconsidered
    • Related is Clausenamide/Szulc et al. 2018
    • Induction of long-term potentiation at hippocampal mossy-fiber synapses follows a Hebbian rule