Anatomy and Function of the Nervous System

• The brain is covered by the skull
• The spinal cord is contained within the vertebral column
• Brain is the most protected encased in the skull and floating in a pool of cerebrospinal fluid (CSF)
• Composed of the brain and spinal cord which makes up the central nervous system
• Composed of the cranial nerves, spinal nerves, and peripheral ganglia which makes up the peripheral nervous system
• Brain receives a copious supply of blood and is chemically guarded by blood-brain barrier
• 1-second interruption of blood flow uses up much of the dissolved oxygen
• 6-seconds interruption of blood flow produces unconsciousness
• Neuraxis is the imaginary straight line drawn from the length of the CNS, from the lower end of the spinal cord up to the front of the brain
• Cross-sections is the transverse cut in the middle of the brain dividing it into the front and back halves
• Sagittal Sections divides the brain into two symmetrical left and right halves
• Parallel cut in the middle of the brain cutting off the upper and lower half of the brain is the Horizontal Sections
• The Prosencephalon or the Forebrain surrounds the lateral and third ventricles
• The Cerebral Cortex surrounds the cerebral hemisphere
• The Cerebral Cortex is greatly convoluted consisting sulci (small grooves) fissure (large grooves) and gyri (bulges between adjacent
• Cell bodies predominate giving it a grayish-tan appearance called the gray matter
• The large concentration of myelin gives this tissue an opaque white appearance called the white matter
• The four lobes of the brain is the (1) Frontal Lobe for emotion control (2) Parietal Lobe for sensation (3) Temporal Lobe for language, hearing and memory (4) Occipital Lobe is for vision
• The 3 Sensory Cortex is the (1) Primary Visual Cortex (2) Primary Auditory Cortex and the (3) Primary Somatosensory Cortex
• The Primary Motor Cortex are connected to different muscles in different parts of the body
• The Motor Association Cortex controls primary motor cortex and directly directs behavior
• Corpus Callosum is the large band of axons that connect corresponding parts of the cerebral cortex to the hemispheres
• The Limbic System is a circuit whose primary function is motivation and emotion
• The Forebrain is divided into the (1) Telencephalon and (2) Diencephalon
• The 4 parts of the Limbic System are the (1) Hippocampus (2) Amygdala (3) Fornix (4) Mammillary Bodies
• A collection of nuclei called the Basal Ganglia, is involved in the control of movement
• The three parts of the Basal Ganglia is the (1) Caudate Nucleus (2) Putamen and (3) Globus Pallidus
• The Diencephalon consists the (1) Thalamus and (2) Hypothalamus
• Hypothalamic hormones are released by specialized neurons called Neurosecretory cells
• The Hypothalamus controls the autonomic nervous system and endocrine system behaviors related to the survival of the species 4Fs: fighting, feeding, fleeing, and mating
• The Tectum or the roof appears as four bumps on the dorsal surface of the brain stem
• The Tegmentum's Reticular Formation regulates sleep-wake: if damage can cause hypersomnolence
• Periaqueductal Gray Matter is the anatomic and functional interface between the forebrain and lower brainstem
• The Hindbrain or the Rhombencephalon surrounds the fourth ventricle
• The Pons that means bridge, contains, in its core, a portion of the reticular formation, and come nuclei that appear to be important in sleep and arousal
• Cerebellum or the little brain has two hemispheres and resembles a miniature version of the cerebrum
• The Medulla Oblongata contains part of the reticular formation including nuclei that control vital functions such as regulation of the cardiovascular system, respiration, and skeletal muscle tone
• The Telencephalon is divided into the (1) Cerebral Cortex (2) Limbic System and (3) Basal Ganglia
• The Mesencephalon or the Midbrain is divided into the (1) Tectum and (2) Tegmentum
• The Hindbrain is divided into the (1) Metencephalon and the (2) Myelencephalon