Chapter 4 Flashcards
Abduction
Vocal fold movement away from each other.
Myelin
A fatty insulator covering the axon that speeds transmission of impulses.
Efferent
Conduction away from a central structure; nerve impulses carried from the brain to the periphery. They carry impulses to muscles and glands from the brain and spinal cord.
Afferent
Axonal fibers that conduct impulses toward the central nervous system; nerve impulses carried from the periphery to the brain. Bring information from the ear, eye, and nose to the brain.
Nuerotransmitters
Chemical messengers of the nervous system; a substance released by hair cells or neurons that affects neighboring neurons.
Glial cells
Support cells of the nervous system.
- they form the myelin covering of axons that speed of transmission of an impulse down the axon
- they serve as a blood-brain barrier for nutrients delivering the neurons
- they remove dead cells from the N.S
Meninges
Tissue coverings overlying the CNS.
Cerebral hemispheres
Two major parts of the cerebrum joined by the corpus callosum.
Gyri
Folds of the cerebral cortex.
Sulci
Furrows of the cerebral cortex.
Longitudinal fissure
Space that separates the medial surfaces of the cerebral hemispheres.
Corpus callosum
Fiber pathways joining the cerebral hemispheres
Sylvian fissure
Horizontal fissure superior to the temporal lobe.
Rolandic fissure
Fissure that divides posterior frontal lobe from anterior parietal lobe.
Basal ganglia
A group of subcortical structures, including the putamen, global pallidus, and caudate, that contributes to control of motor behavior.
Thalamus
Structure located at either side of the third ventricle; responsible for sensorimotor integration and sensory projection to the cerebral cortex.
Brain stem
A portion of the brain containing the midbrain, the pons, and the medulla. The structures are important to speech production.
Cerebellum
Structure at the back of the brain stem; important for motor control. Important for balance and for ensuring of various body movements
Broca’s area
Brodmann’s area 44 located on the third frontal
gyrus anterior to the pre central face area. Functions to program speech movements.
Wernicke’s area
Posterior part of the first temporal gyrus important for auditory processing and comprehension.
Pyramidal tract
Major motor pathway from cerebral cortex to brain stem and spinal cord. Referred to as upper motor neurons.
Extrapyramidal tract
indirect motor pathway made up of networks of neurons.
resting expiratory level
mechanically neutral position of the respiratory system.
adduction
Movement toward the midline; vocal fold movement toward each other.
