EVERYDAY SCIENCE

Detailed explanation-1: -The human brain has often been viewed as outstanding among mammalian brains: the most cognitively able, the largest-than-expected from body size, endowed with an overdeveloped cerebral cortex that represents over 80% of brain mass, and purportedly containing 100 billion neurons and 10× more glial cells.

Detailed explanation-2: -Remarkably, at an average of 86 billion neurons and 85 billion nonneuronal cells (25), the human brain has just as many neurons as would be expected of a generic primate brain of its size and the same overall 1:1 nonneuronal/neuronal ratio as other primates (26).

Detailed explanation-3: -The average adult human brain contains approximately 100 billion neurons, and just as many-if not more-glia. Although neurons are the most famous brain cells, both neurons and glial cells are necessary for proper brain function.

Detailed explanation-4: -Approximately 86 billion neurons in the human brain.

Detailed explanation-5: -Past studies have compared the ‘neural packing density’ in the brains of our favourite carnivorous pets, estimating that cats have about 300 million neurons, roughly doubling the 160 million of dogs.