Lecture 27: Introduction to the Nervous System Flashcards
What are the major divisions of the Nervous System?
- Central Nervous System (brain and spinal cord)
- Peripheral Nervous System (cranial and spinal nerves) –> Enteric Nervous System (smooth muscle, glands of GI tract), Autonomic Nervous System (smooth muscle, cardiac muscle, glands // Parasympathetic and Sympathetic Nervous System), and Somatic Nervous System (skeletal muscle)
What are the two major cell types within the nervous system and their basic functions?
- nerve cells (neurons): process info, sense environmental and internal changes, communicate changes to other neurons, command body responses
- neuroglia: insulate, support, and nourish neurons
List the four major structures of the brain.
- cerebrum
- cerebellum
- diencephalon: thalamus, hypothalamus, epithalamus
- brain stem: midbrain (mesencephalon), pons, medulla oblongata
Describe the organization of the cerebrum in terms of gyri and sulci.
- gyri: folds or bumps in the cerebrum
- sulci: indentations or grooves in the cerebrum
Describe the organization of the cerebrum in terms of hemispheres.
- right hemisphere: pattern perception, music, facial recognition, spatial abilities, visual imagery, discrimination of different smells, generating mental images of sight/sound/touch/taste, artistic awareness, emotional content of language
- left hemisphere: written and spoken language, logic, reason, numerical and scientific skills, ability to understand and use sign language
Describe the organization of the cerebrum in terms of lobes.
- frontal lobe: reasoning, planning, part of speech and movement, emotions, problem solving
- parietal lobe: perception of stimuli related to touch, pressure, temperature, and pain
- temporal lobe: perception and recognition of auditory stimuli and memory
- occipital: many aspects of vision
- insula: integrates autonomic info, associated with visceral function // located deep to frontal, parietal, and temporal lobes
Describe the organization of the cerebrum in terms of gray and white matter.
- gray matter: numerous cell bodies, few myelinated axons
- white matter: numerous myelinated axons, few cell bodies
Describe the organization of the cerebellum in terms of hemispheres and gray and white matter.
- gray matter: cerebellar cortex
- white matter: arbor vittae
List and describe the meningeal layers and spaces from superficial to deep.
- meninges: connective tissue coverings that surround the brain and spinal cord to protect underlying neural tissues AND anchor the brain in the cranial cavity and the spinal cord in the vertebral cavity
- dura mater: subdural space, superficial layer fuses with the periosteum of the skull (not same as spinal cord), inner layer folds to create sinuses
- arachnoid mater: subarachnoid space
- pia mater
What are the dural folds?
- falx cerebri
- falx cerebelli
- tentorium cerebelli
Describe CSF formation.
- produced from arterial blood by the choroid plexuses of the lateral, third, and fourth ventricles by a combined process of diffusion, pinocytosis and active transfer
- small amount is also produced by ependymal cells
What is CSF?
-filtrate of plasma containing glucose, Na+, Cl-, Mg2+, other ions, oxygen, metabolic substances, and WBCs`
Describe CSF function.
- cushioning and shock absorption
- chemical protection
- exchange nutrients and waste
Describe CSF flow.
- heart
- arterial blood
- plasma
- associated ventricle (e.g. lateral) choroid plexus
- ependymal cell
- CSF
- lateral ventricle
- interventricular foramina
- third ventricle
- cerebral aqueduct
- fourth ventricle
- median and lateral aperatures
- subarachnoid space
- arachnoid villi of dural venous sinuses
- venous blood
- heart (REPEATS)
