Brain
The human brain is the main organ of the human central nervous system. It is located in the head, protected by the skull. It has the same general structure as the brains of other mammals, but with a more developed cerebral cortex. Large animals such as whales and elephants have larger brains in absolute terms, but when measured using a measure of relative brain size, which compensates for body size, the quotient for the human brain is almost twice as large as that of a bottlenose dolphin, and three times as large as that of a chimpanzee, though the quotient for a treeshrew's brain is larger than that of a human's. Much of the size of the human brain comes from the cerebral cortex, especially the frontal lobes, which are associated with executive functions such as self-control,planning, reasoning, and abstract thought. The area of the cerebral cortex devoted to vision, the visual cortex, is also greatly enlarged in humans compared to other animals.
The human brain is the command center for the human nervous system. It receives input from the sensory organs and sends output to the muscles. The human brain has the same basic structure as other mammal brains, but is larger in relation to body size than any other brains. The human brain has been called the most complex object in the known universe, and in many ways it's the final frontier of science. A hundred billion neurons, close to a quadrillion connections between them, and we don't even fully understand a single cell.
Anatomy of the human brain
The largest part of the human brain is the cerebrum, which is divided into two hemispheres. Underneath lies the brainstem, and behind that sits the cerebellum. The outermost layer of the cerebrum is the cerebral cortex, which consists of four lobes: the frontal lobe, the parietal lobe, the temporal lobe and the occipital lobe. [Related: Nervous System: Facts, Functions & Diseases]
Like all vertebrate brains, the human brain develops from three sections known as the forebrain, midbrain and hindbrain. Each of these contains fluid-filled cavities called ventricles. The forebrain develops into the cerebrum and underlying structures; the midbrain becomes part of the brainstem; and the hindbrain gives rise to regions of the brainstem and the cerebellum.
Facts about the human brain:
The human brain is the command center for the human nervous system. It receives input from the sensory organs and sends output to the muscles. The human brain has the same basic structure as other mammal brains, but is larger in relation to body size than any other brains. The human brain has been called the most complex object in the known universe, and in many ways it's the final frontier of science. A hundred billion neurons, close to a quadrillion connections between them, and we don't even fully understand a single cell.
Anatomy of the human brain
The largest part of the human brain is the cerebrum, which is divided into two hemispheres. Underneath lies the brainstem, and behind that sits the cerebellum. The outermost layer of the cerebrum is the cerebral cortex, which consists of four lobes: the frontal lobe, the parietal lobe, the temporal lobe and the occipital lobe. [Related: Nervous System: Facts, Functions & Diseases]
Like all vertebrate brains, the human brain develops from three sections known as the forebrain, midbrain and hindbrain. Each of these contains fluid-filled cavities called ventricles. The forebrain develops into the cerebrum and underlying structures; the midbrain becomes part of the brainstem; and the hindbrain gives rise to regions of the brainstem and the cerebellum.
Facts about the human brain:
- The human brain is the largest brain of all vertebrates relative to body size
- It weighs about 3.3 lbs. (1.5 kilograms)
- The brain makes up about 2 percent of a human's body weight
- The cerebrum makes up 85 percent of the brain's weight
- It contains about 86 billion nerve cells (neurons) — the "gray matter"
- It contains billions of nerve fibers (axons and dendrites) — the "white matter"
- These neurons are connected by trillions of connections, or synapses
Brain diseases
Almost everything we do, say and think is controlled by our brain, so when our brain is injured it has the potential to affect every aspect of life.
Brain disorders are often called the hidden disability because there can be serious problems with our behaviour and ability to think, and yet there is often no visible physical change with many brain disorders - so problems can be easily ignored or misunderstood. Even a traumatic brain injury may leave no visible scars to indicate an injury too, place.
Sometimes a person will find even their family members see them as being lazy or hard to get along with, when these are caused by the brain disorder itself. Over two million Australians are affected with some form of brain disorder - that's over one in 12 according to statistics from the World Health Organization.
WHAT IS A BRAIN DISORDER?
A brain disorder is not an intellectual disability. Intelligence is usually not affected, although there are usually cognitive changes such as problems with memory, concentration and attention. It is also not a mental illness, although it can increase the chances of mental disorders such as depression and anxiety.
A brain disorder can affect anyone, but unfortunately it is often the most vulnerable people in the community affected, such as Indigenous Australians, homeless people and survivors of domestic violence.
EFFECTS OF A BRAIN DISORDER
Long-term effects will be different for each person, and will also vary depending on the type of brain disorder. For example, disorders such as Parkinson's disease and multiple sclerosis will leave our cognition (e.g. our ability to think) intact, but have dramatic impacts on the body's ability to control movement.
For more information on brain disorders, please click on the following button.
Brain disorders are often called the hidden disability because there can be serious problems with our behaviour and ability to think, and yet there is often no visible physical change with many brain disorders - so problems can be easily ignored or misunderstood. Even a traumatic brain injury may leave no visible scars to indicate an injury too, place.
Sometimes a person will find even their family members see them as being lazy or hard to get along with, when these are caused by the brain disorder itself. Over two million Australians are affected with some form of brain disorder - that's over one in 12 according to statistics from the World Health Organization.
WHAT IS A BRAIN DISORDER?
A brain disorder is not an intellectual disability. Intelligence is usually not affected, although there are usually cognitive changes such as problems with memory, concentration and attention. It is also not a mental illness, although it can increase the chances of mental disorders such as depression and anxiety.
A brain disorder can affect anyone, but unfortunately it is often the most vulnerable people in the community affected, such as Indigenous Australians, homeless people and survivors of domestic violence.
EFFECTS OF A BRAIN DISORDER
Long-term effects will be different for each person, and will also vary depending on the type of brain disorder. For example, disorders such as Parkinson's disease and multiple sclerosis will leave our cognition (e.g. our ability to think) intact, but have dramatic impacts on the body's ability to control movement.
For more information on brain disorders, please click on the following button.