Its wrinkled surface increases the surface area, and is a six-layered structure found in mammals, called the neocortex. They are; the frontal lobe, the parietal lobe, the occipital lobe and the temporal lobe.
Parietal Lobe — The parietal lobe is located at the upper rear of our brain, and controls our complex behaviors, including senses such as vision, touch, body awareness and spatial orientation. It plays important roles in integrating sensory information from various parts of our body, knowledge of numbers and their relations, and in the manipulation of objects.
Occipital Lobe — The occipital lobe is located at the back of our brain, and is associated with our visual processing, such as visual recognition, visual attention, spatial analysis moving in a 3-D world and visual perception of body language; such as postures, expressions and gestures.
Temporal Lobe — The temporal lobe is located near our ears, and is associated with processing our perception and recognition of auditory stimuli including our ability to focus on one sound among many, like listening to one voice among many at a party , comprehending spoken language, verbal memory, visual memory and language production including fluency and word-finding , general knowledge and autobiographical memories.
A deep furrow divides the cerebrum into two halves, known as the left and right hemispheres. And, while the two hemispheres look almost symmetrical, each side seems to function differently. The right hemisphere is considered our creative side, and the left hemisphere is considered our logical side.
A bundle of axons, called the corpus callosum, connects the two hemispheres. The midbrain is located below the cerebral cortex, and above the hindbrain placing it near the center of the brain. It is comprised of the tectum, tegmentum, cerebral aqueduct, cerebral peduncles and several nuclei and fasciculi. The primary role of the midbrain is to act as a sort of relay station for our visual and auditory systems. Portions of the midbrain called the red nucleus and the substantia nigra are involved in the control of body movement, and contain a large number of dopamine-producing neurons.
The midbrain is the smallest region of the brain, and is located most centrally within the cranial cavity. The cerebral cortex appears grayish brown in color and is called the "gray matter.
The cerebral cortex has sulci small grooves , fissures larger grooves and bulges between the grooves called gyri. Scientists have specific names for the bulges and grooves on the surface of the brain. Decades of scientific research have revealed the specific functions of the various regions of the brain.
Beneath the cerebral cortex or surface of the brain, connecting fibers between neurons form a white-colored area called the "white matter. The cerebral hemispheres have several distinct fissures. By locating these landmarks on the surface of the brain, it can effectively be divided into pairs of "lobes. The cerebrum or brain can be divided into pairs of frontal, temporal, parietal and occipital lobes. Each hemisphere has a frontal, temporal, parietal and occipital lobe.
Each lobe may be divided, once again, into areas that serve very specific functions. The lobes of the brain do not function alone: they function through very complex relationships with one another. Messages within the brain are delivered in many ways. The signals are transported along routes called pathways.
Any destruction of brain tissue by a tumor can disrupt the communication between different parts of the brain. The result will be a loss of function such as speech, the ability to read or the ability to follow simple spoken commands.
Messages can travel from one bulge on the brain to another gyri to gyri , from one lobe to another, from one side of the brain to the other, from one lobe of the brain to structures that are found deep in the brain, e. Research has determined that touching one side of the brain sends electrical signals to the other side of the body.
Touching the motor region on the right side of the brain would cause the opposite side or the left side of the body to move. Stimulating the left primary motor cortex would cause the right side of the body to move. The messages for movement and sensation cross to the other side of the brain and cause the opposite limb to move or feel a sensation.
The right side of the brain controls the left side of the body and vice versa. So if a brain tumor occurs on the right side of the brain that controls the movement of the arm, the left arm may be weak or paralyzed. There are 12 pairs of nerves that originate from the brain itself.
These nerves are responsible for very specific activities and are named and numbered as follows:. The hypothalamus is a small structure that contains nerve connections that send messages to the pituitary gland.
The hypothalamus handles information that comes from the autonomic nervous system. It plays a role in controlling functions such as eating, sexual behavior and sleeping; and regulates body temperature, emotions, secretion of hormones and movement.
The pituitary gland develops from an extension of the hypothalamus downwards and from a second component extending upward from the roof of the mouth. The frontal lobes are the largest of the four lobes responsible for many different functions. These include motor skills such as voluntary movement, speech, intellectual and behavioral functions. The areas that produce movement in parts of the body are found in the primary motor cortex or precentral gyrus.
The prefrontal cortex plays an important part in memory, intelligence, concentration, temper and personality. The premotor cortex is a region found beside the primary motor cortex. Broca's area, important in language production, is found in the frontal lobe, usually on the left side. These lobes are located at the back of the brain and enable humans to receive and process visual information. They influence how humans process colors and shapes.
The occipital lobe on the right interprets visual signals from the left visual space, while the left occipital lobe performs the same function for the right visual space. These lobes interpret simultaneously, signals received from other areas of the brain such as vision, hearing, motor, sensory and memory. These lobes are located on each side of the brain at about ear level, and can be divided into two parts.
One part is on the bottom ventral of each hemisphere, and the other part is on the side lateral of each hemisphere. An area on the right side is involved in visual memory and helps humans recognize objects and peoples' faces. An area on the left side is involved in verbal memory and helps humans remember and understand language.
This system is involved in emotions. Included in this system are the hypothalamus, part of the thalamus, amygdala active in producing aggressive behavior and hippocampus plays a role in the ability to remember new information. This gland is an outgrowth from the posterior or back portion of the third ventricle. In some mammals, it controls the response to darkness and light.
In humans, it has some role in sexual maturation, although the exact function of the pineal gland in humans is unclear. The pituitary is a small gland attached to the base of the brain behind the nose in an area called the pituitary fossa or sella turcica.
The pituitary is often called the "master gland" because it controls the secretion of hormones. The pituitary is responsible for controlling and coordinating the following:. This is a cavity in the back part of the skull which contains the cerebellum, brainstem and cranial nerves The thalamus serves as a relay station for almost all information that comes and goes to the cortex.
It plays a role in pain sensation, attention and alertness. It does this by:. The brain stem is located in front of the cerebellum and connects to the spinal cord. It consists of three major parts:. There are hundreds of conditions that can affect the brain. Most of them fall within one of five main categories:. Learn more about the different types of brain conditions. Brain injury symptoms depend on the type and severity of the injury.
While they sometimes appear immediately after a traumatic event, they can also show up hours or days later. Neurodegenerative diseases cause damage to nervous tissue over time, so their symptoms may get worse as time goes on. Symptoms of psychological conditions can be very different from person to person, even when they involve the same condition. Follow these tips to keep your brain in good health and to reduce your risk of certain brain conditions:. Improve your mental fitness by regularly reading, learning, or doing activities that make you think, such as crossword puzzles.
All of these help stimulate your nerve cells, and may even lead to the development of new brain cells. Always wear a helmet when playing contact sports. Be sure to buckle up when you get in the car. Both of these can go a long way when it comes to avoiding brain injuries.
While smoking is bad for your overall health , it can also lead to cognitive decline. Try to check in from time to time with your thoughts or feelings. Keeping a diary is a good way to get into this habit. Look for any thought patterns or emotions that seem to be impacting your day-to-day life. They could be a sign of an underlying, treatable psychological condition.
In the body there are two deep temporal arteries. These arteries are called the posterior and anterior deep temporal arteries. The hypothalamus is a small but crucial part of the brain. It controls several important functions, including sleep and growth. Learn more about its…. The body of fornix joins the hippocampus and mammillary bodies, structures in the base of the brain that are involved in memory formation and recall….
The fornix commissure is a thin, triangular sheet of transverse horizontal fibers. It is located on the inside of the brain's fornix, which is the…. The pons is a portion of the brain stem, located above the medulla oblongata and below the midbrain.
Although it is small, at approximately 2. The amygdaloid body is also known as the amygdaloid nucleus. This is an oval structure located within the temporal lobe of the human brain. The putamen is a large structure located within the brain. It is involved in a very complex feedback loop that prepares and aids in movement of the…. In the brain, oxygenated blood travels through an extensive and central cerebral arterial circle. This network is called the circle of Willis.
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