introduction to the hippocampus the hippocampus is the most important (i.e., most obvious and...
Post on 21-Dec-2015
219 views
TRANSCRIPT
![Page 1: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/1.jpg)
Introduction to the Hippocampus
The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection of brain structures located on the inner border of the neocortex that process olfactory information, regulate emotion and encode memory.
![Page 2: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/2.jpg)
Why “Hippocampus”?
The basis for the name is unclear, but human hippocampus bears a resemblance to a seahorse.
![Page 3: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/3.jpg)
More Nomenclature
The hippocampus is also called Ammon’s Horn (cornu ammonis), after the Egyptian god Ammon (Amun) Ra, who was often depicted with ram’s horns.
Depiction of Ammon Ammon’s Horn, seen from the top of the brain
![Page 4: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/4.jpg)
Hippocampus: Rodent versus Man
The volume of the human hippocampus is about 100 times larger than a rat’s, and about 10 times larger than a monkey’s.
![Page 5: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/5.jpg)
Structure of the Hippocampus
• Basic structure preserved across species• Hippocampal formation
consists of two regions:– Dentate gyrus– Hippocampus proper
![Page 6: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/6.jpg)
Subdivisions of the Hippocampus: the CA (Cornus Ammonis) Fields
![Page 7: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/7.jpg)
Two Types of Principle CellsHippocampal Pyramidal Neuron
Dentate Granule Cell
![Page 8: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/8.jpg)
Structure of the Dentate Gyrus
Stratum moleculare:
Outer 2/3 receives input from entorhinal cortex
Inner 1/3 receives input from CA3
Stratum granulosum
Dentate hilus
![Page 9: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/9.jpg)
Structure of CA3
sl-m
Stratum lacunosum-moleculare:receives afferents from entorhinal cortex
Stratum radiatum:receives afferents from CA3 (ipsi & contra)
Stratum pyramidale
Stratum oriens:receives afferents from CA3 (ipsi & contra)
Stratum lucidum:receives mossy fiber input from dentate gyrus
![Page 10: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/10.jpg)
Structure of CA1
Stratum lacunosum-moleculare:receives afferents from entorhinal cortex
Stratum radiatum:receives afferents from CA3 (ipsi & contra)
Stratum pyramidale
Stratum oriens:receives afferents from CA3 (ipsi & contra)
![Page 11: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/11.jpg)
Basic Hippocampal Connections
![Page 12: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/12.jpg)
Modulatory Inputs to Hippocampus
Attention Mood Reward Novelty
![Page 13: Introduction to the Hippocampus The hippocampus is the most important (i.e., most obvious and interesting looking) structure in the limbic system, a collection](https://reader036.vdocuments.net/reader036/viewer/2022062407/56649d575503460f94a3566a/html5/thumbnails/13.jpg)
Hippocampal Output
Originally proposed to play a role in control of emotion; likely also involve in memory storage
: