Limbic system functions


In 1878, Paul Broca, a French neurologist known for his so-called Broca's aphasia, coined the term "le grand lobe lymbique". The term "limb" refers to an edge or edge. Dr. Broca was referring to the structures that surround the innermost part of the brain, at the edge of the center of the brain.

Roxanne Wegner / Getty Images

The importance of the limbic system

The meaning of the term "limbic system" has changed since Brock's time. It is still designed to include structures between the cortex and the hypothalamus and the brainstem, but different specialists have included different structures as part of the limbic system. The amygdala and hippocampus are extensively included, as is the olfactory cortex. Therefore, however, opinions differ as to what is considered part of the limbic system and what is paralimbic, meaning a structure that closely interacts with, but is not part of, the limbic system.

What does the limbic system do?

The limbic system has many basic cognitive and emotional functions. The hippocampus, located on the inner border of the temporal lobes, is essential for memory formation. The tonsils are located at the top of the front of each hippocampus. Each amygdala is believed to be important for processing emotions. The amygdala interacts closely with the hippocampus, which helps explain why we remember more emotionally important things. The amygdala also interacts closely with the hypothalamus, an area of the brain responsible for regulating temperature, appetite, and several other basic processes necessary for life. The hypothalamus itself is sometimes, but not always, part of the limbic system. Through the hypothalamus, as well as some key areas of the brain stem, the limbic system interacts with our autonomic nervous system (which regulates things like heart rate and blood pressure), the endocrine system, and the viscera (or "gut") .

Nerve cells in the brain are organized differently based on their location. The cerebral cortex is predominantly neocortical, which means that the cells exist in 6 layers. This is in contrast to the limbic system, where cells are arranged in fewer layers (eg, Paleocorticoid) or more intermixed (corticosteroid). This less complex organization of the limbic system, as well as its control over fundamental life processes, led physicians to conclude that the limbic structure is evolutionarily older than the cerebral cortex.

Paralimbic structures

The paralimbic structures form a complex network with the limbic system. Examples of paralimbic structures include the cingulate gyrus, the orbitofrontal cortex, the temporal pole, and part of the insula. The basal forebrain, nucleus accumbens, mammillary bodies, and parts of the thalamus (anterior and mediodorsal nuclei) are also considered paralimbic structures due to their close interaction with the limbic system.

Each of these paralimbic structures is associated with basic emotions or cognitive processes. For example, the anterior cingulate gyrus is associated with motivation and drive. The islet is related to our ability to experience our own internal sensations (or "internal sensations"). The orbitofrontal cortex , nucleus accumbens, and basal forebrain are associated with sensations of pleasure or reward. The mammillary bodies and some nuclei of the thalamus are important for the formation of new memories.

All these paths are inextricably linked. The amygdala, for example, communicates with the orbitofrontal pathway through a bundle of white matter called the hooked bundle , much like the islet. The amygdala communicates with parts of the hypothalamus and the cingulate gyrus through the terminal strip, as well as with the brainstem and some other structures through the ventral tonsil. The hippocampus communicates primarily through a large white matter pathway called the fornix, which curves around the ventricles of the brain into the mammillary bodies, sending branches to the mammillary bodies, the thalamus, and the cingulate gyrus.

The limbic system is a heterogeneous group of structures and has many different functions. These functions are critical to the way we think, feel, and respond to the world around us.

Related Articles
Choosing foods to diet after a heart attack

All cardiovascular specialists agree that a healthy diet is important to reduce the risk of coronary artery disease (CHD) Read more

Different types of hysterectomies.

A hysterectomy is the surgical removal of all or part of a woman's uterus . Hysterectomy is usually done Read more

Esthetician: experience, specialties and training

An esthetician is a person who specializes in cosmetic skin care. Cosmetologists (sometimes called estheticians ) are not medical Read more

Benefits, Side Effects, Dosages, and Interactions.

CBD oil is an extract from Cannabis indica or Cannabis sativa , the same plants that produce marijuana when Read more