What does a Nervous System do for you?
Detect (sense) changes in the environment (light, sound, smell, taste, touch, heat) Detect (sense) changes in the internal environment (blood pressure, blood chemistry, temperature, etc.) Integrate and evaluate sensory information Plan, problem-solve, predict Store and retrieve information (memory) Control contractions of skeletal muscles (movements / behavior) Control internal glands, muscles (heart rate, hormone secretions, metabolism) The Nervous System Organization
Central Nervous System - completely surrounded by bone - suspended in cerebrospinal fluid - covered by meninges - protected by blood-brain barrier Peripheral Nervous System - nerves leaving and entering the CNS - motor nerves = control muscles and glands - sensory nerves = transmit information to the CNS from sensory receptors. - cranial nerves (bottom of brain) and spinal nerves (from spinal cord) are the foundation from which all other peripheral nerves emerge. Nervous System showing spinal nerves emerging from the spinal cord
Small segment of spinal cord Showing two pairs of spinal nerves There are 31 pairs all together. Spinal Cord Functions 1. receive sensory input from receptors 2. provide motor output to muscles and glands. 3. coordinate reflexes 4. ascending and descending tracts How the Peripheral and Central Nervous Systems Interact Terminology Associated with the Nervous System
Neuron: Neuroglia (Glial cells): Nerve: Ganglion:Nucleus: Central Nervous System:Peripheral Nervous System: Somatic:Autonomic: Sensory (Afferent):Efferent (motor): The Brain Has a Rich and Complex Blood Supply
That Provides the Nerve Tissue with Oxygen and Nutrients While Removing Caron Dioxide and Wastes Ventricles of the Brain Contain Cerebrospinal Fluid
That Buoys the Brain and Provides Nutrients and Cushioning Lateral (There are two) aqueduct 3rd 4th ParietalBone Frontal Bone Temporal Bone Occipital Bone Central Sulcus Gyrus (ridge) Sulcus (groove) Parietal lobe Frontal lobe Lateral sulcus Temporal lobe Occipital lobe cerebellum Central Sulcus cerebrum Gyrus (ridge) Sulcus (groove) Transverse Fissure Lateral Fissure Pons cerebellum Medulla oblongata Post-Central Gyrus Pre-Central Gyrus Parietal Lobe Frontal Lobe
Sommatosensory cortex Pre-Central Gyrus Sommatomotor cortex Parietal Lobe Frontal Lobe Temporal Lobe Occipital Lobe Somatomotor Area Somatosensory Area Sensory- Wernikes Area Primary Visual Area Moror Speech Brocas Area Audotory Area Three Dimensional Somatosensory Homunculus Basal Nuclei (Ganglia)
Caudate Nucleus Lentiform Nucleus putamen globus pallidus Substantia Nigra Subthalamic Nucleus Limbic System Cingulate gyrus Hypothalamus Amygdala Hippocampus Location of Thalamus Relative to Basal Nuclei (ganglia) Cerebral cortex (gray matter)
Corpus callosum Basal nuclei Basal nuclei thalamus thalamus Basal nuclei Basal nuclei Temporal lobe Temporal lobe Midbrain pons Basal nuclei Thalamus Corpus Callosum Thalamus Hypothalamus Pituitary Pons Midbrain Medulla oblongata Gray matter (cortex) White Matter Thalamus Projection fibers Ascending and Descending tracts Superior View Horizontal Sections of Brain
Transverse = a section that cuts the body into top (superior) and bottom (inferior) portions. Longitudinal fissure Central sulcus Commissural fibers Lateral Ventricles Thalamus Associationfibers Olfactory bulb Optic Chiasma Infundibulum Optic nerve Mammillary body pons Medulla oblongata cerebellum Optic nerve Optic chiasma Infundibulum Mammillary body Inferior View of Brain and Cranial Nerves Nervous System showing spinal nerves emerging from the spinal cord
Small segment of spinal cord Showing two pairs of spinal nerves There are 31 pairs all together. Spinal Cord Functions 1. receive sensory input from receptors 2. provide motor output to muscles and glands. 3. coordinate reflexes 4. ascending and descending tracts Spinal Cord cervical swelling Spinal Nerves Nerve Plexes lumbar swelling Cauda Equina Spinal cord Spinal nerves Cauda equina Spinal nerve Dorsal root ganglion Dorsal Root Ganglia Nerve roots Spinal nerve Spinal Cord Transverse Section Dorsal Root ganglion Dorsal Root Ventral Root
Dorsal Horn Lateral Horn Ventral Horn Location of spinal cord inside canal of vertebra
Gray Matter Spinal Nerve White Matter Body of Vertebra White matter Dorsal root ganglion Ventral root Gray matter Dorsal root Organization of the Spinal Cord
dorsal root Sensory neuron cell body Dorsal root ganglion sensory Spinal nerve motor Ventral root From Receptor Motor neuron cell body To Effector Simple Knee Jerk Reflex Coordinated by the Spinal Cord
Dorsal root Dorsal root ganglion Sensory neuron Quadriceps muscle Motor neuron Ventral root Withdrawal Reflex interneuron AscendingTracts Descending tracts Detail of Retina Eye Optic Nerve Light Rods and cones Optic Chiasma Geniculate Nucleus Right Visual Field Primary Visual Cortex Left Visual Field Thalamus