The Brain

1. 1.CEREBRUM - is the largest part of the brain and is composed of right and left hemispheres. It performs higher functions like interpreting touch, vision and hearing, as well as speech, reasoning, emotions, learning, and fine control of movement.
2. CEREBELLUM- located under the cerebrum. Its function is to coordinate muscle movements, maintain posture, and balance.
3. BRAIN STEM- includes the midbrain, pons, and medulla. It acts as a relay center connecting the cerebrum and cerebellum to the spinal cord. It performs many automatic functions such as breathing, heart rate, body temperature, wake and sleep cycles, digestion, sneezing, coughing, vomiting, and swallowing. Ten of the twelve cranial nerves originate in the brainstem.

Annotations:

• DEFINITION: The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals.

1. Frontal lobe: Personality, behavior, emotions Judgment, planning, problem solving Speech: speaking and writing (Broca’s area) Body movement (motor strip) Intelligence, concentration, self awareness
2. Parietal lobe- Interprets language, words Sense of touch, pain, temperature (sensory strip) Interprets signals from vision, hearing, motor, sensory and memory Spatial and visual perception
3. occipital lobe: Interprets vision (color, light, movement)
4. temporal lobe: Understanding language (Wernicke’s area) Memory Hearing Sequencing and organization

1. Hypothalamus- is located in the floor of the third ventricle and is the master control of the autonomic system. It plays a role in controlling behaviors such as hunger, thirst, sleep, and sexual response. It also regulates body temperature, blood pressure, emotions, and secretion of hormones.
2. Pituitary Gland- lies in a small pocket of bone at the skull base called the sella turcica. The pituitary gland is connected to the hypothalamus of the brain by the pituitary stalk. Known as the “master gland,” it controls other endocrine glands in the body. It secretes hormones that control sexual development, promote bone and muscle growth, respond to stress, and fight disease.
3. Pineal Gland is located behind the third ventricle. It helps regulate the body’s internal clock and circadian rhythms by secreting melatonin. It has some role in sexual development.
4. Thalamus serves as a relay station for almost all information that comes and goes to the cortex (Fig. 5). It plays a role in pain sensation, attention, alertness and memory.