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André F. de Sousa

@desousa1.bsky.social

Neuroscientist. Investigating how memories are formed and organized.

André F. de Sousa @desousa1.bsky.social · 28/04/2026

I am deeply grateful to my supervisor @alcinosilva, collaborators, and all lab members and students who made this possible.

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André F. de Sousa @desousa1.bsky.social · 28/04/2026

Take-home: The PFC controls whether new experiences are linked with prior memories by restricting which neurons are recruited for memory encoding. This mechanism provides a bridge between long-term memories and memory organization processes relevant for knowledge formation.

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André F. de Sousa @desousa1.bsky.social · 28/04/2026

This pathway also regulates which neurons are recruited to encode new memories (independent of their pre-learning activity) revealing a new mechanism for controlling memory allocation based on prior experience.

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André F. de Sousa @desousa1.bsky.social · 28/04/2026

Mechanistically, this control operates via a PFC → MEC → hippocampus circuit and involves modulation of ensemble overlap via neurogliaform inhibitory neurons in dCA1.

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André F. de Sousa @desousa1.bsky.social · 28/04/2026

This reveals a top down control mechanism over memory organization in the hippocampus.

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André F. de Sousa @desousa1.bsky.social · 28/04/2026

When mice encoded two different contexts 7 days apart: -> mPFC activity increased When we inhibited mPFC during encoding: -> Memories became linked -> Neuronal overlap increased in dCA1 -> Behavior was directly affected

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André F. de Sousa @desousa1.bsky.social · 28/04/2026

Using a mouse model of memory linking, we show that the prefrontal cortex is recruited over time to control how memories are linked in the hippocampus.

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André F. de Sousa @desousa1.bsky.social · 28/04/2026

Memories are not formed in isolation and are often integrated, or linked, with prior knowledge. Sometimes this is useful. Sometimes it can be dangerous. How does the brain decide which memories to connect and which to keep separate?

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André F. de Sousa @desousa1.bsky.social · 28/04/2026

It is finally out! Excited to share the main work from my postdoc in the Silva Lab at UCLA. We investigated how memories are organized in the brain (rdcu.be/ffPmX).

rdcu.be

The prefrontal cortex controls memory organization in the hippocampus

Nature Neuroscience - Related memories are sometimes encoded in overlapping neurons. The authors show that the prefrontal cortex controls this type of memory organization in the hippocampus through...

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