CURRENT AFFAIRS

Detailed explanation-1: -The highest IPC is found in humans, followed by the great apes, Old World and New World monkeys. The IPC of cetaceans and elephants is much lower because of a thin cortex, low neuron packing density and low axonal conduction velocity.

Detailed explanation-2: -They found that neuron density was highest in the second visual area (not V1), followed by primary somatosensory cortex. Primary motor cortex was the least neuron-dense cortical area.

Detailed explanation-3: -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-4: -Elephants have the largest brains of all terrestrial mammals, including the greatest volume of cerebral cortex.

Detailed explanation-5: -Not Just a Case of Bigger Brains Results showed that the dogs, having larger brains to begin with, had more than twice as many neurons in their cerebral cortex as the domestic cat, with around 530 million cortical neurons to the cat’s 250 million. (For comparison, there are billions of neurons in the human brain.)