Search results
Results from the WOW.Com Content Network
The brain is the central organ of the human nervous system, and with the spinal cord makes up the central nervous system. It consists of the cerebrum, the brainstem and the cerebellum. The brain controls most of the activities of the body, processing, integrating, and coordinating the information it receives from the sense organs, and making ...
The evolutionary history of the human brain shows primarily a gradually bigger brain relative to body size during the evolutionary path from early primates to hominins and finally to Homo sapiens. This trend that has led to the present day human brain size indicates that there has been a 2-3 factor increase in size over the past 3 million years ...
The largest brains are those of sperm whales, weighing about 8 kg (18 lb). An elephant's brain weighs just over 5 kg (11 lb), a bottlenose dolphin's 1.5 to 1.7 kg (3.3 to 3.7 lb), whereas a human brain is around 1.3 to 1.5 kg (2.9 to 3.3 lb). Brain size tends to vary according to body size. The relationship is not proportional, though: the ...
Dunbar's number. Dunbar's number is a suggested cognitive limit to the number of people with whom one can maintain stable social relationships—relationships in which an individual knows who each person is and how each person relates to every other person. [1][2] This number was first proposed in the 1990s by British anthropologist Robin ...
The evolution of human intelligence is closely tied to the evolution of the human brain and to the origin of language. The timeline of human evolution spans approximately seven million years, [ 1 ] from the separation of the genus Pan until the emergence of behavioral modernity by 50,000 years ago. The first three million years of this timeline ...
The triune brain is a model of the evolution of the vertebrate forebrain and behavior, proposed by the American physician and neuroscientist Paul D. MacLean in the 1960s. The triune brain consists of the reptilian complex (basal ganglia), the paleomammalian complex (limbic system), and the neomammalian complex (neocortex), viewed each as ...
Homo naledi. Homo naledi is an extinct species of archaic human discovered in 2013 in the Rising Star Cave system, Gauteng province, South Africa (See Cradle of Humankind), dating to the Middle Pleistocene 335,000–236,000 years ago. The initial discovery comprises 1,550 specimens of bone, representing 737 different skeletal elements, and at ...
Cortical white matter increases from childhood (~9 years) to adolescence (~14 years), most notably in the frontal and parietal cortices. [8] Cortical grey matter development peaks at ~12 years of age in the frontal and parietal cortices, and 14–16 years in the temporal lobes (with the superior temporal cortex being last to mature), peaking at ...