• The human brain contains 100 billion neurons, which come in thousands of types and collectively form an estimate of more than 100 trillion interconnections• Nerve cells (neurons) have two main types of branches; dendrites, which receive incoming messages, and axons which carry outgoing signals
• These neurons communicate with other cells through electrical impulses when the nerve cell is stimulated. Within a neuron, the impulse moves to the tip of an axon and causes the release of neurotransmitters, chemicals that act as messengers. Neurotransmitters pass through the synapse, the gap between two nerve cells, and attach to receptors on the receiving cell. This allows you to move, think, feel, and communicate
• The cerebellum coordinates movement by combining sensory information from the eyes, ears and muscles. “The brainstem links the brain to the spinal cord. It controls heart rate, blood pressure and breathing, it is also important for sleep
• The cerebrum is divided into two halves (hemispheres). The hemispheres communicate with each other through a thick tract of nerves, called the corpus callosum, at the base of the fissure. Messages to and from one side of the body are usually handled by the opposite side of the brain
• The area that controls movement is the motor strip, which is a very narrow strip that is located near the top of the head and goes down along the ear line
• The frontal lobe controls thinking, planning, organizing, problem solving, short- term memory, movement, and speech• An area on the left side of the frontal lobe is called Broca’s area, and it processes language by controlling the muscles that make sounds (mouth, lips and larynx). Damage to this area results in motor aphasia, in which patients can understand language but cannot produce meaningful or appropriate sounds
• This lobe interprets sensory information, such as taste, temperature, touch and pain.• The rear of the parietal lobe (next to the temporal lobe, which we will talk about soon) has a section called Wernicke’s area, which is important for understanding the sensory (auditory and visual) information associated with language. Damage to this area of the brain produces what is called sensory aphasia, in which patients cannot understand language but can still produce sounds
• It processes images form your eyes and then links it with stored images from the memory (parietal lobe) and motor cortex (frontal lobe).• One of the things this lobe must do is interpret the upside-down images of the world that are projected onto the retina by the lens of the eye
• Like the parietal lobe, the temporal lobe processes information from your senses, and also deal with memory storage• There are four parts of the brain that are located in the temporal lobe; the basal ganglia, limbic system, hippocampus, and amygdala.
• First, the basal ganglia coordinates fingertip movements and other fine motions.• Second, the limbic system, which is located deep within the temporal lobe, Is important in emotional behavior and controlling movements of visceral muscles (muscles of the digestive tract and body cavities). The limbic system is comprised of the cingulate gyrus, corpus callosum, mammillary body, olfactory tract, amygdala and hippocampus
• Next, is the hippocampus, which is important for short- term memory.• Lastly, the amygdala controls sexual and social behavior
• The lower brain contains the spinal cord, brain stem and diencephalon.• The medulla, which is in the brain stem, has a nuclei for controlling blood pressure and breathing, as well as a nuclei for getting information from the sense organs in from the cranial nerves.
• There is also a part in the brain stem called the pons. The pons contains nuclei that relay movement and position information from the cerebellum to the cortex. It also contains nuclei that are involved in breathing, taste and sleep, and physically connects medulla to the midbrain.
• From there we can now talk about the spinal cord.• The spinal cord is merely a downward extension of the brain stem.• It contains objects such as the midbrain, thalamus, and hypothalamus.
• The thalamus also passes messages between the spinal cord and the cerebral hemispheres.• Next, is the hippocampus, this part sends memories to be stored until they are needed to be recalled
• Finally, is the hypothalamus, “the hypothalamus contains nuclei that control hormonal secretions from the pituitary gland. These centers govern sexual reproduction, eating, crucial urges, temperature, drinking, growth, and maternal behavior such as lactation. The hypothalamus is also involved in almost all aspects of behavior, including your biological “clock,” which is linked to the daily light-dark cycle