LIMBIC SYSTEM
→ Starts & terminate in hypocampus.
- The limbic system is composed of several cortical and subcortical structures, that participate in a complex network of connections to regulate complicate behaviors such as memory, emotions, hemostatic functions and motivational state. (group of white & grey mater structures)
Structures:
- Limbic lobe: 2 componants → BA 23,24,25,29,30,31
- ↳ Cingulate gyrus (memory+emotions)
- ↳ Parahippocampal gyrus (memory)
- Hipocampal formation: (memmory).
- Located within the medial temporal lobe.
- Made up from:
- Hippocampus (curved structures).
- ↳ Converting short term memory to long term memory.
- 2. Dentate gyrus: lies between the parahippocampal gyrus & the hippocampus.
- 3. Subiculum: transitional area btw. the parahipocampal gyrus & the hipocampus.
- Amygdala: (emotions & behaviour) of fear ← Inside the uncus gyrus
- Is an almond-shaped structure. (The largest nucleus)
- Consists of 3 nuclear regions:
- large basolateral group
- Small corticomedial group (olfaction).
- ↳ Which includes the central nucleas.
- Hypothalamus: located below the thalamus & above the pituitary gland.
- Contains: Mammillary bodies
- Thalamus: directing sensory info. to the appropiate areas"
- Contains.
- Ant. nucleus.
- Medialodorsal nucleus.
- Septum - beneath the rostal pt. of the corpus callosum
- Habenula
* The efferent fibers arising from the hippocampus form a thin layer of white matter called alveus, which converge to form a bundle called fimbira wich becomes continous with the crus of the fornix.
- Fornix: An arching band of white matter that connects the hypocampus to hypothalamus (mamillary bodies
- ↳ Consists of 3 parts:
- Crus - begins from the fimbria of hippocampus
- Body - Below corpus callosum (behind the body is the fornix commisure)
- (2) Ant. columns - end in mammilary bodies.