Overall brain size doesn't correlate with level of intelligence for non-human animals. For instance, the brain of a sperm whale is more than five times heavier than the human brain, but humans are considered to be of higher intelligence than sperm whales. A more accurate measure of an animal's likely intelligence is the ratio between the size of the brain and body size, although not even that measure puts humans in first place: The tree shrew has the highest brain-to-body ratio of any mammal, according to BrainFacts.
Among humans, brain size doesn't indicate a person's level of intelligence. Some geniuses in their field have smaller-than-average brains, while others have brains that are larger than average, according to Christof Koch , a neuroscientist and president of the Allen Institute for Brain Science in Seattle. For example, compare the brains of two highly acclaimed writers. The Russian novelist Ivan Turgenev's brain was found to weigh 71 ounces 2, grams , while the brain of French writer Anatole France weighed only 36 ounces 1, g.
The reason behind humans' intelligence, in part, is neurons and folds. Humans have more neurons per unit volume than other animals, and the only way they can all fit within the brain's layered structure is to make folds in the outer layer, or cortex, said Dr.
Other intelligent animals, such as monkeys and dolphins, also have these folds in their cortex, whereas mice have smooth brains, he said. How the brain is integrated also seems to matter when it comes to intelligence. A genius among geniuses, Albert Einstein had an average size brain; researchers suspect his mind-boggling cognitive abilities may have stemmed from its high connectivity, with several pathways connecting distant regions of his brain, Live Science previously reported.
Humans also have the largest frontal lobes of any animal, Holland said. The frontal lobes are associated with higher-level functions such as self-control, planning, logic and abstract thought — basically, "the things that make us particularly human," he said. The human brain is divided into two hemispheres, the left and right, connected by a bundle of nerve fibers called the corpus callosum.
The hemispheres are strongly, though not entirely, symmetrical. Generally, the left brain controls the muscles on the right side of the body, and the right brain controls the left side. One hemisphere may be slightly dominant, as with left- or right-handedness. Thalamus The thalamus sits on top of the brain stem.
Cerebrum, cerebral cortex and brain hemispheres The cerebrum is involved in functions of higher consciousness. These include: Frontal - located behind the forehead.
Functions include consciousness, thinking, emotions, language and memory. Parietal - located on the top and rear of the head. These lobes process information from the sensory nerves and contribute to voluntary movement. Temporal - located over each ear. Functions include memory and processing sounds, face recognition, recognition of complex objects and multi-sensory integration.
Occipital - located at the back of the head. The main function is interpretation of sensory information from the eyes. Corpus callosum The two hemispheres are connected by a thick band of nerve fibres called the corpus callosum.
Other important structures Other structures of the brain include: Hypothalamus - located underneath the thalamus. This structure plays an important role in regulating many bodily processes including temperature, thirst, hunger, sleep and libido.
It works hand in hand with another brain structure, the pituitary gland. Limbic system - made up of various structures including the hippocampus and amygdala. This primitive area of the brain is responsible for basic emotions like anger, happiness and sexual desire. A range of disorders The brain can be affected by a wide range of disorders and events. Tumours - growths usually start in the cells of the meninges, the glial cells of the cerebellum or cerebral hemispheres, or in the pituitary gland.
Stroke - the rupturing of a blood vessel in the brain or a blockage of blood vessels. Congenital defects - including genetic disorders such as Down syndrome, or developmental problems caused by maternal consumption of alcohol or drugs during pregnancy.
Trauma - such as a blow to the head or a penetrating injury. Drugs - including alcohol. Some drugs are neurotoxins poisonous to nerve cells. With all the other things it does, is it any surprise that the brain runs your emotions? Maybe you got the exact toy you wanted for your birthday and you were really happy. Or your friend is sick and you feel sad. Where do those feelings come from? Your brain, of course. Your brain has a little bunch of cells on each side called the amygdala say: uh-MIG-duh-luh.
Scientists believe that the amygdala is responsible for emotion. Sometimes you might feel a little sad, and other times you might feel scared, or silly, or glad. Note: All information on KidsHealth is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. All rights reserved.
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Satellite Locations. Emergency Care. Urgent Care. DOI: Edwards JD, et al. Speed of processing training results in lower risk of dementia. There is evidence that regular stimulation that comes from engaging in artistic activities such as painting and sewing, listening to music, and even socializing have been shown to improve and preserve cognitive function.
Roberts Or, et al. Risk and protective factors for cognitive impairment in persons aged 85 years and older. Mayo Clinic study points to modifiable risk factors of mild cognitive impairment [Press release].
Physical exercise has also been proven to improve cognitive functioning, mood, and well-being. Mandolesi L, et al. Effects of physical exercise on cognitive functioning and wellbeing: Biological and psychological benefits.
Physical exercise and dementia. Your brain is made up of different parts that all work together. The cerebrum is located at the front and is the largest part of the brain. Each hemisphere is divided into four regions, which are called lobes.
Each lobe is responsible for different functions, such as:. The cerebellum is located in the back of your brain.
It helps with the coordination and movement related to motor skills, especially involving the hands and feet. It also helps maintain posture, balance, and equilibrium. This is located at the base of your brain and connects your brain to your spinal cord.
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