Chapter 14: Brain and Cranial Nerves Flashcards
Rostral
Toward the forehead
Caudal
Toward the spinal cord
3 major portions of the brain
Cerebrum, Cerebellum and Brainstem
Longitudinal Fissure
Deep groove that separates the cerebral hemispheres
Gyri
thick folds
Sulci
shallow grooves
Corpus Collosum
thick nerve bundle at bottom of longitudinal fissure that connects hemispheres
Gray Matter
the seat of neurosomas, dendrites, and synapses
Dull color due to little myelin
Forms surface layer (cortex) over cerebrum and cerebellum
Forms nuclei deep within brain
White Matter
bundles of axons
Lies deep to cortical gray matter, opposite relationship in the spinal cord
Pearly white color from myelin around nerve fibers
Composed of tracts, or bundles of axons, that connect one part of the brain to another, and to the spinal cord
Ependyma
type of neuroglia that lines ventricles and covers choroid plexus
Produces cerebrospinal fluid
Cerebrospinal Fluid (CSF)
clear, colorless liquid that fills the ventricles and canals of CNS
Function of CSF
Buoyancy, Protection and Chemical Stability
Brain barrier system
regulates what substances can get from bloodstream into tissue fluid of the brain
Although blood is crucial, it can also contain harmful agents
Two points of entry must be guarded
Blood capillaries throughout the brain tissue
Capillaries of the choroid plexus
Central Pattern Generators
neural pools that produce rhythmic signals to the muscles of breathing and swallowing
Reticular Formation
Loose web of gray matter that runs vertically through all levels of the brainstem
Occupies space between white fiber tracts and brainstem nuclei
Has connections with many areas of cerebrum
More than 100 small neural networks without distinct boundaries
Reticular Formation Functions
Somatic motor control, cardiovascular control, pain modulation, sleep, consciousness and habituation
Cerebellum
important for motor coordination and locomotor ability
Forebrain
consists of Diencephalon: encloses 3rd ventricle, most rostral part of brainstem and Telencephelon: develops into cerebrum
Diencepholon
3 parts: thalamus, hypothalamus and epithalamus
Hypothalamus
major control center of autonomic nervous system and endocrine system
Cerebrum
largest, most conspicuous part of human brain. Seat of sensory perception, memory, thought, judgment, and voluntary motor actions
Basal Nuclei
masses of cerebral gray matter buried deep in the white matter, lateral to the thalamus
Higher Brain Functions
sleep, memory, cognition, emotion, sensation, motor control, and language
Electroencephalogram (EEG)
monitors surface electrical activity of the brain waves
Cognition
the range of mental processes by which we acquire and use knowledge
Hippocampus
important limbic system area for memory
Amygdala
emotional memory
Special Senses
Vision, Hearing, Equilibrium, Taste and Smell
General Senses
Touch, pressure, stretch, movement, heat, cold and pain
Wernicke Area
Posterior to lateral sulcus usually in left hemisphere
Permits recognition of spoken and written language
When we intend to speak, Wernicke area formulates phrases and transmits plan of speech to Broca area
Broca Area
Inferior prefrontal cortex usually in left hemisphere
Generates motor program for the muscles of the larynx, tongue, cheeks, and lips for speaking and for hands when signing
Transmits program to primary motor cortex for commands to the lower motor neurons that supply relevant muscles
Left Hemisphere
Analytical
Right Hemisphere
Artistic
Positron emission tomography (PET)
allows researchers to visualize increases in blood flow when brain areas are active
Functional magnetic resonance imaging (fMRI)
looks at increase in blood flow to an area—magnetic properties of hemoglobin depend on how much oxygen is bound to it
