Why Does an Octopus Have Nine (9) Brains?

Why Does an Octopus Have Nine (9) Brains?

Certainly, upon learning that Octopus have nine (9) brains, many of us picture out them this way. But the truth is, their brain structure is different from a human brain, and they don't literally have nine (9) brains, they only have one (1), which is the central brain located right between the eyes forming a donut-like shape structure that wrapped around the esophagus, while the eight (8) others, which are said to be the mini-brains, found at the base of each of their eight tentacles, are actually cluster of nerve cells or ganglia.

Each arm is controlled by a complex nervous system comprising of more than 40 millions neurons that are linked to around three hundred (300) suckers and millions of sense receptors, and this neurons are connected to the one hundred eighty (180) million neurons found in the central brain, hence adds up to 500 million neurons in total.

Octopus' decentralized nervous system due to its distributed brain power, offers more opportunities for exploration. The fact that most neurons are in the arms, roughly 2/3 of them, gives them the ability to take and process sensory information from the environment, that's why they can move, touch and taste semi-autonomously, which means they can act even without the aid of the central brain.

When the octopus craves for food, the central brain work with the major role, sending signal to its arms commanding them to search for something to eat. Each arms will then start exploring in the ocean floor, feeling and tasting every object they encounter. It's motor control system then process some of the sensory information gathered to initiate necessary movements, be it by walking, crawling, extending, shortening, twisting their arms and any other motion to conveniently search for a delicious meal and when its sensory receptors detect that the object is a prey, those sensory information, the taste, texture, and the condition of the detected food will be sent to the central brain, to initiate more important steps, whether to catch and bring the food to it's mouth, or to reject and look for other yummy meal.

Such delegation of power allows the octopus to do more complex tasks simultaneously and ease the burden of the central brain from performing not so vital duty, since the best use of the central brain is to be on guard from the attack of predators, and therefore can quickly react to threats.

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