Chapter 9 - Reticular Formation & Limbic system Flashcards
3 longitudinal Columns of the Reticula Formation
- Median column
- Medial column
- Lateral column
“M”edian”L” has L meaning it is more “L”ateral than median with no “L”
Size of neurons in:
(1) Median longitudinal column
(2) Medial longitudinal column
(3) Lateral longitudinal column
(1) Intermediate sized neurons
(2) Large sized neurons
(3) Small sized neurons
Media”N” for i”N”termediate, media”L” one L for “Large”. “L”atera”L” two Ls for sma”LL”
Reticular Formation Relations:
(1) superiorly
(2) inferiorly
(3) laterally
(1) cerebral cortex
(2) interneurons of spinal cord gray matter
(3) cerebellum
Reticular Formation Functions (#7)
- control of skeletal muscle
- control of facial expression muscle
- control of somatic and visceral sensations
- control of ANS
- control of endocrine system
- influence biologic clock
- reticular activating system (consciousness)
Location of reticular formation
At the center of the cerebrospinal axis
at the brinstem (?)
Components of the Hippocampal Formation
1) hippocampus
2) dentate gyrus
3) parahippocampal gyrus
Hippocampus is a curved elevation of gray matter that extends throughout the entire length of the floor of the inferior horn of the lateral ventricle
Hippocampus
A curved elevation of gray matter that extends throughout the entire floor of the inferior horn of the lateral ventricle
Limbic System Structures
- amygdaloid nucleus
- parahippocampal gyri
- hippocampal formation
- subcallosal
- cingulate
- mammillary bodies
- anterior thalamus nuclei
Limbic system connecting pathways
*alveus
*fimbria
*fornix
*mammillothalamic tract
*stria terminalis
white nerve fibers extending from hippocampus converging into the fimbria
alveus
Notch of gray matter that lies between the parahippocampal gyrus and the fimbria
Dentate gyrus
Thin vestigial layer of gray matter that covers the superior surface of the corpus callosum (below cingulate gyrus)
Indusium griseum
posteriorly, the dentate gyrus accompanies the fimbria and becomes continuous to the indusium griseum
Between the hippocampal fissure and the collateral sulcus;
continuous with the hippocampus along the medial edge of the temporal lobe
parahippocampal gyrus
Nuclei groups of the amygdala
*basolateral group (larger)
*corticomedial group (smaller)
Connects the Right and left crura of the fornix to form the body of the fornix
commissure of the fornix
Foramen of Monro
The body of the fornix splits anteriorly into two columns of the fornix that curves anteriorly and inferiorly over the foramen of monro
Interventricular foramen connects the lateral ventricles and the 3rd ventricle
Major output pathway of the limbic system
Hypothalamus
Emotional behavior influenced by the limbic system
Fear, anger, sexual behavior
Converts short term memory to long term memory
Hippocampus