Chapter 13 - Brain and Cranial Nerves Flashcards
Four major divisions of the brain
-Brainstem
-Cerebellum
-Diencephalon
-Cerebrum
Medulla oblongata
-Most inferior part of brainstem
-Has pyramids
-Where inferior fibers decussate
-Olives - nuclei within help with balance, coordination, modulation of sound
-Has nuclei of cranial nerves V, IX-XII
Pons
-Superior to medulla oblongata
-Pontine nuclei - relay between cerebrum and cerebellum
-Sleep and respiratory centers
Midbrain
-Superior to pons
-Nuclei of cranial nerves III-V
-Tectum - four nuclei form mounds (2 superior colliculi involved in visual reflexes, 2 inferior involved in hearing)
-Red nuclei - unconscious regulation/coordination of motor activities
-Tegmentum (ascending tracts)
Reticular formation
-Group of nuclei scattered throughout brainstem
-Arousal, sleep/wake cycle, awareness, posture, pain
-Help coordinate breathing, swallowing, heart rate
Cerebellum major features
-Posterior to pons
-Ridges (folia)
-Arbor vitae
-More neurons than entire cerebral cortex
-Flocculonodular lobe, vermis, and lateral hemispheres
-Peduncles to communicate
Cerebellum functions
-Control of muscle movement/tone
-Balance
-Regulate extent of intentional movement
-Learning motor skills
Purkinje cells
-Largest cells in CNS
-Inhibitory
-Receive input from 200,000 synapses
Thalamus
-Sensory info synapses here before projecting to cerebrum
-Lateral portions connected by interthalamic adhesion
Subthalamus
-Functions as part of subcortical basal nuclei in controlling motor function
-Contains subthalamic nuceli
Epithalamus
-Superior and posterior to thalamus
-Habenula (motivation control, behavior)
-Pineal gland (sleep/wake cycle, biorhythms)
Hypothalamus
-Most inferior part of diencephalon
-Mammillary bodies (odors)
-Infundibulum (controls endocrine system)
-Regulates mood (etc)
Central sulcus
-Separates frontal and parietal lobes
-Between precentral gyrus and postcentral gyrus
Cerebral medulla
White matter between cortex and nuclei
Basal nuclei
Gray matter within medulla
Precentral gyrus
Primary motor cortex
Postcentral gyrus
Primary somatic sensory cortex
Parietal lobe
Reception/evaluation of sensory info except smell, hearing, or vision
Cerebral medulla
White matter between cortex and nuclei
Projection fibers
Tracts between the cerebrum and other parts of the brain and spinal cord
Association fibers
Connections within the same hemisphere
Commissural fibers
Connect one hemisphere to the other
Basal nuclei
-Motor function control
-Found in the midbrain, cerebrum, diencephalon
Limbic system
-Part of cerebrum and diencephalon
-Basic survival functions (memory, reproduction, nutrition)
-Emotions
-Cingulate gyrus and hippocampus in cerebrum
