Welcome to 2 minute neuroscience, where I simplistically explain neuroscience topics
in 2 minutes or less.
In this installment I will discuss the limbic system.
The word limbic comes from the Latin limbus, which means border, and the limbic system
was given this name because its structures lie along a horseshoe shaped area of cortex
that appears to be a border between the cerebral cortex and the subcortical structures of the
There are many processes associated with the limbic system, but the system is most frequently
linked to emotion.
There is no consensus on the structures that are considered a part of the limbic system,
and some argue that it is too much of a simplification to consider something as complex as emotion
to be handled by one group of brain structures.
Regardless, these are some structures that are often included in the limbic system.
The amygdala is an almond-shaped collection of nuclei found in the temporal lobe that
seems to be especially involved with fearful and anxious emotions.
The hippocampus is next to and interconnected with the amygdala.
Although it is considered part of the limbic system, the hippocampus is generally associated
with memory moreso than emotion.
The parahippocampal gyrus is an area of cortex that surrounds the hippocampus and also plays
a role in memory.
The cingulate cortex or cingulate gyrus is found just above the corpus callosum and is
involved in various aspects of emotion and memory.
The septal nuclei have connections with a number of other limbic structures, and are
thought to be especially important to pleasure, reward, and reinforcement.
The mammillary bodies are two groups of nuclei that are involved in memory and have extensive
connections with the amygdala and hippocampus.
The fornix is a fiber bundle that carries information from the hippocampus to the mammillary
bodies and then on to the thalamus.
The hypothalamus controls hormone release via the anterior pituitary and can exert widespread
influence over bodily states to maintain homeostasis.
While there are other structures that may be included in the limbic system, the structures
identified here are some that are commonly considered part of it.