The scientists were able to record the brain activity of octopuses without disturbing their freedom of movement. This is reported by the Japanese Institute OIST.
“If we want to understand how the brain works, octopuses are the perfect animal to compare to mammals. They have a large brain, a unique body, and developed cognitive abilities that have evolved in a completely different way than vertebrates,” explained Tamar Gutnik, one of the authors of the study.
However, octopuses do not have a skull on which to attach electrodes to take an encephalogram, and therefore, previously, researchers were only able to record data from immobilized octopuses. Therefore, now scientists have decided to place the devices directly inside the body of animals. It was based on compact and lightweight data loggers, originally designed to track the brain activity of birds during flight. Scientists have adapted the devices to make them waterproof, yet small enough to easily fit inside octopuses. Batteries, necessary for operation in an airless environment, allowed continuous recording up to 12 hours.
Next, the researchers anaesthetized three Octopus cyanea octopuses and implanted the recorder into the cavity of the muscular wall of the mantle. The scientists then implanted electrodes in the vertical lobe and middle upper frontal lobe of the octopus’s brain. This area of the brain is believed to be important for visual learning and memory.
After the operation was completed, the octopuses were placed in an aquarium and their behavior was recorded on video. The brain recording worked fine and was then superimposed on the recorded video. The scientists now plan to investigate the connection between the animal’s brain activity and its apparent behavior.