Researchers are unlocking the minds of octopuses, revealing why these creatures rank among the planet’s sharpest thinkers. They learn rapidly, store lessons, and apply them in new situations. The big question: how does an octopus brain work when it combines a central brain with eight flexible peripheral systems in each tentacle? A collaborative team has reached a milestone by recording brainwaves from octopuses moving freely. The result is striking: octopuses display extraordinary neural dynamics and cognitive potential.
Octopuses lack a rigid skeleton and possess eight highly adaptable arms that operate with a surprising degree of autonomy and coordination. Their nervous system is expansive, featuring a central brain and many neurons spread across multiple lobes. In many animals, researchers link brain activity to behavior by placing electrodes on the skull and matching electrical signals to observed actions. For octopuses, the flexible body and absence of a rigid frame make such recordings especially challenging.
Four decades of work confronted a barrier: attaching recording equipment without restricting movement or causing harm was nearly impossible. The octopus’ ability to maneuver its eight arms and remove foreign objects complicated measurements of brain activity during untethered movement.
That barrier is being overcome. Recording electrical signals in a freely moving octopus demanded creative engineering to keep the animal safe and comfortable while data were collected.
A resting octopus on the seabed vividly illustrates its natural habitat. The study relied on underwater scenes, using photographs that show the animal in its element.
Lead author and former researcher Tamar Gutnick, from the Okinawa Institute of Science and Technology, explains that wires would be easily ripped off. The team developed a method to tuck the recording equipment under the skin so the octopus could move without interference, enabling long-term observation without anesthesia.
Twelve hours of continuous recording
The recent work, featured in Current Biology, presented a portable data logger mounted in the octopus and electrodes placed in the vertical lobe system of the brain. The devices were lightweight and compact, originally designed to monitor bird brain activity during flight but adapted for aquatic life. Waterproofing and size adjustments allowed a snug fit inside the octopus, with battery power sustaining twelve hours of data collection in a low-oxygen environment.
Researchers chose the larger great blue octopus for this study, anesthetizing three individuals to insert recording devices into a mantle-wall cavity. Electrodes targeted the vertical lobe and upper frontal regions, areas believed to be important for visual learning and memory).
As data were gathered, simultaneous video documented the animals’ behavior as they slept, fed, and moved freely. The team could then correlate brain activity with observed actions over a lengthy recording period without restraining the animals.
Patterns emerged in the brain activity that appeared consistently across all subjects. Some signals resembled activity seen in mammalian nervous tissue, while other slower oscillations had not been documented previously in octopuses.
Enhanced cognitive abilities
Although direct links between specific brain patterns and particular behaviors could not be established from the video alone, the study marks a first step in understanding how octopus brains govern behavior. It also offers clues about universal principles underlying the development of intelligence and cognition. The region studied is associated with learning and memory, and future work will pursue repetitive memory tasks to further map this circuit. The researchers anticipate testing with octopuses soon to explore how these animals learn, socialize, and coordinate the movements of their tentacles.
Researchers emphasize that studying the octopus brain provides a compelling comparison with mammals. The octopus has a large brain and an unusual body form, shaped through a distinct evolutionary path. Its cognitive abilities are high, yet many questions about brain operation remain. The new recording technique makes it possible to look inside the brains as octopuses perform tasks, which is both exciting and powerful, according to the project leader from the Physics and Biology Unit at OIST.
Science teams from Japan, Italy, Germany, Ukraine and Switzerland contributed to the work. The study is documented in Current Biology and builds on prior investigations into neural activity in cephalopods.