How do octopuses remember what they learn? A new study reveals a surprising “molecular switch” in the octopus brain that helps preserve memories by keeping connections between nerve cells strengthened over time, without the need to produce new proteins. The discovery sheds new light on one of nature’s greatest mysteries: how creatures with vastly different brains evolved remarkably sophisticated learning and memory abilities.
How does an octopus remember what it has learned? A new study led by Dr. Ana Luiza Turchetti-Maia, Dr. Tal Shomrat and Prof. Binyamin (Benny) Hochner from the Hebrew University and Ruppin Academic Center has uncovered a previously unknown molecular mechanism that may help explain how these remarkably intelligent animals form and maintain memories.
The findings, published in Journal of Neuroscience , reveal that the octopus brain uses a unique “molecular switch" to maintain strengthened connections between nerve cells. The discovery offers new insights into how sophisticated learning and memory mechanisms evolved independently in animals whose evolutionary lineage diverged from ours hundreds of millions of years ago.
Octopuses are renowned for their remarkable cognitive abilities, including problem-solving, exploration, and learning from experience. Despite their evolutionary distance from humans, they possess sophisticated learning and memory systems.
The research focused on a brain region called the vertical lobe , which, like the hippocampus in vertebrates, plays a central role in learning and memory. Like the hippocampus, the octopus vertical lobe can strengthen connections between neurons in response to brief, strong stimulation through a process known as long-term potentiation (LTP), widely considered one of the fundamental cellular mechanisms underlying learning and memory.
However, the researchers discovered that octopuses maintain these strengthened connections through a surprisingly different molecular process.
At the heart of the discovery is nitric oxide (NO), a tiny gaseous molecule that acts as a messenger between nerve cells. The team found that NO plays a dual role: it mediates strengthening of synaptic connections by facilitating neurotransmitter release and, helps maintain this strengthening by persistently activating nitric oxide synthase (NOS), the enzyme responsible for its own production.
This creates a self-sustaining positive feedback loop — effectively a molecular switch that once turns ON helps keep synaptic connections strengthened over time.
Remarkably, the researchers found that unlike many well-studied forms of memory-related plasticity in vertebrates, in the octopus, this process can maintain long-term potentiation without requiring the production of new proteins, challenging conventional expectations about the molecular processes that sustain long-lasting changes in neural connections.
“What makes this discovery so exciting is that octopuses have evolved a fundamentally different molecular solution to a challenge shared by all learning system: how to turn brief experience into a long-lasting change in neural connections,,” explains Prof. Benny Hochner. “It is a remarkable example of how evolution can give rise to similar principles of learning and memory through very different biological mechanisms”
Beyond revealing another fascinating aspect of octopus intelligence, the discovery highlights how studying animals with independently evolved nervous systems can deepen our understanding of the biological foundations of learning and memory.
JNeurosci
10.1523/JNEUROSCI.1676-25.2026
Experimental study
Animals
A novel nitric oxide (NO)-dependent ‘molecular switch’ mediates LTP in the Octopus vulgaris brain through persistent activation of nitric oxide synthase (NOS).