THE BRAIN

CEREBRUM

The cerebrum or cortex is the largest part of the human brain, associated with higher brain function such as thought and action. The cerebral cortex is divided into four sections, called "lobes": the frontal lobe, parietal lobe, occipital lobe, and temporal lobe.

Frontal Lobe Functions:Consciousness. How we initiate activity in response to our environment. Judgments we make about what occurs in our daily activities. Controls our emotional response. Controls our expressive language. Assigns meaning to the words we choose. Involves word associations. Memory for habits and motor activities.

Parietal Lobe Functions:Location for visual attention. Location for touch perception. Goal directed voluntary movements. Manipulation of objects. Integration of different senses that allows for understanding a single concept.

Occipital Lobe

Associated with visual processing

Temporal Lobe

Hearing ability

Memory acquisition

Some visual perceptions

Categorization of objects.

DIENCEPHALON

1. Thalamus - is a relay station for sensory impulses, except smell, passing upward to the sensory cortex. All memory, sensation, and pain impulses also pass through this section of the brain.

2. Hypothalamus - plays an important role in the endocrine system because it regulates the pituitary secretion of hormones that influence metabolism, reproduction, stress response, and urine production. It works with the pituitary to maintain fluid balance and maintains temperature regulation by promoting vasoconstriction or vasodilation. In addition, the hypothalamus is the site of the hunger center and is involved in appetite control. It contains centers that regulate the sleep-wake cycle, blood pressure, aggressive and sexual behavior, and emotional responses.

3. Epithalamus - forms the roof of the third ventricle. Important parts of the epithalamus are the pineal body (part of the endocrine system) and the choroids plexus of the third ventricle. The choroids plexus, knots of capillaries within each ventricle, from the cerebrospinal fluid.

Cerebellum The cerebellum integrates information from the vestibular system that indicates position and movement and uses this information to coordinate limb movements (posture and balance).

Brain Stem

This structure is responsible for basic vital life functions such as breathing, heartbeat, and blood pressure.

1. Midbrain

The midbrain contains nuclei that link the various sections of the brain involved in motor functions, eye movements and auditory control.

2. 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.

3. Medulla

The medulla contains nuclei for regulating blood pressure and breathing, as well as nuclei for relaying information from the sense organs that comes in from the cranial nerves.

THE SPINAL CORD

The spinal cord provides a tow-way conduction pathway to and from the brain, and it is a major reflex center.

PERIPHERAL NERVOUS SYSTEM

consists of

sensory neurons running from stimulus receptors that inform the CNS of the stimuli

motor neurons running from the CNS to the muscles and glands - called effectors - that take action.