What is the Limbic System?
The limbic system is a group of structures located deep within the brain that are involved in emotional responses such as fear, anger, sadness, joy and other emotions. These reactions are usually triggered when we experience negative events or situations.
These emotions are often accompanied by physical symptoms such as sweating, trembling, shaking, nausea and other unpleasant feelings. These physical symptoms may occur without any conscious awareness. They are known as autonomic nervous system (ANS) responses.
In addition to these functions, the limbic system is also involved in learning and memory by processing information that comes through the senses. In other words, it has a role in the storage and retrieval of information as well as the formation of memories.
Structure of the limbic system
There are several limbic system structures that are important to keep in mind when discussing this topic. They are:
The amygdala are almond-shaped groups of neurons (nerve cells) that are located on each side of the brain. It processes emotional reactions such as fear and anger. These emotions are generally related to survival in some way. The amygdala is essential in processing memories such as associated with a particular place or event.
The hippocampus is a seahorse-shaped structure located within the limbic system. It is primarily involved in processing memories. In fact, the word hippocampus comes from a Greek word that means sea horse. The hippocampus is also involved in controlling certain autonomic nervous system (ANS) functions such as heart rate.
The word thalamus comes from the Greek word for “inner chamber” and it is a structure that is shaped like an eye. The thalamus is involved in relaying sensory information to the cerebral cortex. For example, the thalamus receives signals from the optic nerve and sends this information to the visual areas of the cerebral cortex.
For this reason, it is sometimes referred to as the sensory relay nucleus. The thalamus also has functions that are related to sleep. During sleep, the thalamus limits the signals that are sent to the cerebral cortex. This results in diminishing sensory data which in turn causes dreams.
The hypothalamus is a tiny region of the brain that contains several important nuclei. It is involved in maintaining homeostasis such as body temperature, hunger, thirst and the sleep-wake cycle. It is also involved in emotions, behavior and learning.
The hypothalamus consists of several different nuclei that are involved in specific functions. For example, the mammillary body is involved in the sleep-wake cycle. The preoptic area is involved in controlling the body temperature.
The suprachiasmatic nucleus is involved in controlling the circadian rhythm or biological clock. The ventromedial nucleus is involved in controlling functions that are essential for survival such as eating and drinking. The lateral part of the hypothalamus consists of cells that are involved in regulating emotions. This area is involved in pride, fear, rage and anger. Injury to this area often results in emotional disturbances.
Sources & references used in this article:
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