Limbic system Flashcards
Elements of larger outer circle
parahippocampal gyrus uncus cingulate gyrus subcallosal gyrus orbitofrontal gyrus
Elements of smaller inner circle
dentate gyrus indusium griseum/ fornix paraterminal gyrus hippocampal formation amygdala diagonal band of broca
Hippocampus
Afferent fibers: parahippocampal gyrus contralateral hippocampus dentate gyrus Schaffer's collaterals cingulate gyrus thalamus septal region amygdala hypothalamus Efferent fibers: fornix papez ring dentate gyrus- indesium griseum - lateral + medial longitudinal stria
Amygdaloid complex function
implicated in emotional processing
involved in mediating stress on hippocampus memory processes
Diagonal band of Broca
connects amygdaloid complex to septal area
Neurons in septum pellucidum
to habenular nuclei (stria medullaris)
Functions of limbic system
Aggression and defense Nutrition Food differentiation Sexual behavior Motherhood protection Memory and learning
Papez ring
Hippocampus - fornix - mammillary body - mammillo-thalamic tract - anterior thalamic nucleus - cingulate gyrus - hippocampus
Amygdaloid ring
Amygdala - stria terminalis - septum pellucidum - stria medullaris thalami - habenular nuclei - fasciculus retro flexus - inter-peduncular nucleus - brain stem reticular formation - amygdala
Nuclei in limbic system
mammillary bodies anterior nucleus of thalamus MD nucleus of thalamus habenular nuclei dorsal/ventral tegmental nuclei interpeduncular nuclei locus ceruleus raphee nuclei
Inputs to limbic system
- olfactory system
- spinothalamic tract
- cerebral cortex
Outputs of limbic system
- medial forebrain bundle
- dorsal longitudinal fasicle of Schultz
- Retroflex fasciculus of Mienert
- Cingulate gyrus
- extrapyramidal system
Hippocampal formation function
memory
memory processing functions- from short to long
anger, motivation, consciousness, aggression
Basolateral nuclei of amygdaloid complex
relations: sensory association cortex, frontal lobe, ventral striatum, nucleus accumbens, Meynert’s nucleus basalis, dorsal thalamus
projections from: olfactory bulb, entorhinal cortex, cingulate gyrus, subcallosal area
efferents: stria terminalis to septal area, preoptic area and hypothalamus nuclei. Entorhinal area, hypothalamus, medial thalamic nuclei
Stria terminalis rich with peptidergic fibers
Corticomedial nuclei of amygdaloid complex
descending pathways to n. dorsalis n. vagi, brainstem cardiovascular center, locus ceruleus, n. raphe dorsalisventral tegmental nucleus
-peptidergic neurons
hypothalamus
