The Limbic SystemHow Low Can You Go…?

The Limbic System

• The limbic system includes nuclei and tracts along the borders between the cerebrum and the diencephalon• It contains structures that are

located along the outskirts of both sections• Instead of a simple anatomical

structure, this is actually a grouping of functioning components

The Limbic System

• The limbic system has several job responsibilities• This is because it contains many

different structures that branch across many different systems• There are many different

components that all function together to help the brain process

The Limbic System

• The limbic system… • 1) Helping to establish emotional

states• 2) Linking the conscious,

intellectual functions with the unconscious, autonomic functions• 3) Facilitating memory storage

and retrieval

Video

• https://www.youtube.com/watch?v=LNs9ruzoTmI

Structures of the Limbic System

• The limbic system contains many different structures• There are several different

structures that act within the limbic system that we already know about• These include the hypothalamus,

parts of the thalamus and the reticular formation

Structures of the Limbic System

• Other structures of the limbic system tie together the functions of all systems• The amygdaloid body (commonly

refereed to as the amygdala) is the link between the cerebrum, various sensory systems and the limbic system• It plays a role in linking memories

to emotions, regulating heart rate and the “fight or flight” response

Structures of the Limbic System

• The hippocampus is one of the main structures involved in the storage and formations of memory• It is located inferior to the lateral

ventricles• It looked like a mythical seahorse

named “hippocampus”

Demo

• http://faculty.washington.edu/chudler/stm0.html

• https://faculty.washington.edu/chudler/puzmatch.html

Structures of the Limbic System

• The mamillary bodies are two structures that are close to the hypothalamus• The mamillary bodies help to

control eating urges and reflexes such as licking, chewing and swallowing• They also help process auditory

input

Structures of the Limbic System• The fornix is a small tract of white

matter that connects the hippocampus and the hypothalamus• A few strands of the fornix also

connect those structures to the mamillary bodies• While its exact function is still

unclear, several tests have been performed on it• When the fornix is severed the

patient can have memory loss and have trouble forming memories