The brain of the domesticated cat is about 5cm (2in) long and weighs 25 – 30g (0.88 – 1.06oz). For a typical cat about 60cm (24in) long and a weight of 3.3 kg (7.3 lb), the brain would be at 0.91% of its total body mass, compared to 2.33% of total body mass in the average human.
Despite the size differences, according to researchers at Tufts University School of Veterinary Medicine, the physical structure of cat and human brains are very similar. Both species have cerebral cortices with similar lobes specialized to perform different tasks. The brains of cats and humans are both folded on the surface, allowing more brain to fit into a smaller area.
The cerebral cortex is the part of the brain responsible for learning, information processing, and decision-making. It is here that inputs from the senses and lower areas of the brain come together to be interpreted and acted upon. The surface area of the cat's cerebral cortex is about 83 cm2, whereas the human cerebral cortex has a surface area of around 2500 cm2. The cat has an estimated 300 million neurons in its cerebral cortex.