Sirota Lab — Progressive, Reproducible Workflow Bootcamp

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title: "MemoryConsolidation"
author: "Arash Shahidi"
theme: "black"
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height: 720 
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# 🧠 Sleep and Memory Consolidation

- During **sleep**, short-term memories in the **hippocampus** are stabilized into long-term cortical storage.  
- Non-REM (NREM) sleep supports this process.  
- Central question: *How does the hippocampus communicate with cortex during sleep?*

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# ⚡ Sharp-Wave Ripples (SWRs)

- Brief, high-frequency (150–250 Hz) hippocampal events during NREM sleep.  
- Coordinate reactivation (“replay”) of neurons encoding recent experiences.  
- Thought to drive information transfer to cortex.

**[Animation placeholder: SWR waveform + ripple burst firing]**

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# 🔁 Memory Reactivation (“Replay”)

- Neurons that fired during learning **replay** their activity during SWRs.  
- This replay can also be observed in **prefrontal cortex (PFC)**.  
- Only ~10–30% of SWRs show replay → not all are memory-relevant.

**[Animation placeholder: waking sequence vs. sleep replay]**

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# ❓ Key Question

- Are certain SWRs (e.g., large ones) specifically responsible for memory reactivation?  
- Do they causally contribute to better memory performance?

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# 💡 Closed-Loop Optogenetic Boosting

- Detect SWRs in real time and deliver a light pulse to **amplify** them.  
- Tests whether **enhanced SWRs** increase hippocampus–PFC reactivation and memory.

**[Animation placeholder: SWR detection → blue light → boosted ripple]**

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# 🧬 Findings

- **Large SWRs** linked to stronger replay in hippocampus and PFC.  
- Their frequency increases after learning.  
- **Boosting SWRs**:
  - Enhanced ensemble reactivation  
  - Improved later memory recall  
  - Increased hippocampus–PFC synchrony

**[Plot placeholder: Control vs. Boosted memory performance]**

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# 🔗 Summary

- Sleep SWRs coordinate memory replay and hippocampo-cortical communication.  
- Only a subset (“large SWRs”) drives consolidation.  
- Causal boosting strengthens both neural replay and behavioral recall.

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