Wracking the Octopus Brain

Delving into the brain of an octopus is becoming a trusted means of learning more about how humans can save and access their memories.

Octopuses and other related creatures, known as cephalopods, are considered to be the most intelligent invertebrates because they have relatively large brains and they can be trained for various learning and memory tasks, says Dr. Benny Hochner of the Department of Neurobiology at the Alexander Silberman Institute of Life Sciences at the Hebrew University of Jerusalem.

Their behavior repertoire and learning and memory abilities are even comparable in their complexity to those of advanced vertebrates. However, they are still invertebrate mollusks with brains that contain a much fewer number of nerve cells and much simpler anatomical organization than that of vertebrate brains. This unique constellation was utilized to tackle one of the most interesting questions in modern neuroscience: how the brain stores and recalls memories.

Hochner's results demonstrate that, like in mammals (including humans), the short and long-term memory in the octopus are segregated into two separate systems, each in different locations in the brain. It is not completely understood how these two systems are interconnected, if at all. However, the organization in the octopus demonstrates a sophistication that was not described yet in other animals.

In the octopus, the short-term and long-term memory systems work in parallel, but not independently. This is so because the long-term memory area — in addition to its capacity to store long-term memories — also regulates the rate at which the short-term memory system acquires short-term memories. This regulatory mechanism is probably useful in cases where faster learning is significant for the octopus' survival in emergency or risky situations.

-- LiveScience Staff

• Image Gallery: Under the Pacific
• 10 Amazing Things You Didn’t Know About Animals
• Oddly, Octopuses Have Ephemeral Elbows