Anatomy and physiology of the brain
Anatomy and physiology of the brain and spinal cord
The brain is a spongy organ made up of nerve and supportive tissues. It is located in the head and is protected by a bony covering called the skull. The base, or lower part, of the brain is connected to the spinal cord. Together, the brain and spinal cord are known as the central nervous system (CNS). The spinal cord contains nerves that send information to and from the brain. The CNS works with the peripheral nervous system (PNS). The PNS is made up of nerves that branch out from the spinal cord to relay messages from the brain to different parts of the body. Together, the CNS and PNS allow a person to walk, talk, throw a ball and so on.
Structure and function of the brain
The brain is the body’s control centre. It constantly receives and interprets nerve signals from the body and responds based on this information. Different parts of the brain control movement, speech, emotions, consciousness and internal body functions, such as heart rate, breathing and body temperature. The brain has 3 main parts: cerebrum, cerebellum and brain stem.
Cerebrum
The cerebrum is the largest part of the brain. It is divided into 2 parts (halves) called the left and right cerebral hemispheres. The 2 hemispheres are connected by a bridge of nerve fibres called the corpus callosum. The right half of the cerebrum (right hemisphere) controls the left side of the body. The left half of the cerebrum (left hemisphere) controls the right side of the body. The outer surface of the cerebrum is called the cerebral cortex or grey matter. It is the area of the brain where nerve cells make connections, called synapses, that control brain activity. The inner area of the cerebrum contains the insulated (myelinated) bodies of the nerve cells (axons) that relay information between the brain and spinal cord. This inner area is called the white matter because the insulation around the axons gives it a whitish appearance.
The brain is a spongy organ made up of nerve and supportive tissues. It is located in the head and is protected by a bony covering called the skull. The base, or lower part, of the brain is connected to the spinal cord. Together, the brain and spinal cord are known as the central nervous system (CNS). The spinal cord contains nerves that send information to and from the brain. The CNS works with the peripheral nervous system (PNS). The PNS is made up of nerves that branch out from the spinal cord to relay messages from the brain to different parts of the body. Together, the CNS and PNS allow a person to walk, talk, throw a ball and so on.
Structure and function of the brain
The brain is the body’s control centre. It constantly receives and interprets nerve signals from the body and responds based on this information. Different parts of the brain control movement, speech, emotions, consciousness and internal body functions, such as heart rate, breathing and body temperature. The brain has 3 main parts: cerebrum, cerebellum and brain stem.
Cerebrum
The cerebrum is the largest part of the brain. It is divided into 2 parts (halves) called the left and right cerebral hemispheres. The 2 hemispheres are connected by a bridge of nerve fibres called the corpus callosum. The right half of the cerebrum (right hemisphere) controls the left side of the body. The left half of the cerebrum (left hemisphere) controls the right side of the body. The outer surface of the cerebrum is called the cerebral cortex or grey matter. It is the area of the brain where nerve cells make connections, called synapses, that control brain activity. The inner area of the cerebrum contains the insulated (myelinated) bodies of the nerve cells (axons) that relay information between the brain and spinal cord. This inner area is called the white matter because the insulation around the axons gives it a whitish appearance.