The term “limbic system” refers to a functional unit localized in the brain that serves primarily to process emotional impulses. In addition, the limbic system controls the development of drive behavior. The processing of essential components of intellectual performance is also attributed to the limbic system.
In connection with these complex processes, however, the limbic system cannot be regarded as a separate functional unit. Rather, the limbic system works in harmony with a large number of nerve cells in the cerebral cortex. Consequently, the development of emotions and drive behavior is based on a lively exchange of information between many parts of the brain.
Anatomy of the limbic system
The functional unit of the brain known as the “limbic system” comprises several anatomical structures. Within the brain, the individual components of the limbic system form a double ring around the so-called basal ganglia and the thalamus. Historically, the individual structures of the limbic system evolved from old parts of the cerebral cortex (palaeopallium and archipallium) and cells located directly below the cerebral cortex. The anatomical structure of the limbic system is shown in: The individual components of the limbic system are in close contact with different regions of the entire brain and are capable of processing complex information.
- Hippocampus
- Fornix
- Corpus mamillare
- Gyrus cinguli
- Corpus amygdaloideum (almond kernel)
- The anterior nuclei of the thalamus
- Gyrus parahippocampalis
- Septum pallucidum
Hippocampus
The hippocampus is evolutionarily one of the oldest structures of the brain. The exact location of the hippocampus is in the temporal lobe. Each of the two halves of the brain has a hippocampus.
As the central switching station, it serves as an important part of the functional complex known as the “limbic system”. The hippocampus itself consists of excitatory nerve cells that receive their information mainly from the cerebral cortex. In this part of the limbic system, information from various sensory brain areas come together.
This information is processed in the nerve cells of the hippocampus and sent back to the cerebral cortex. One of the most important functions of this part of the limbic system is memory consolidation. This means that the direct transfer of information from short-term to long-term memory is controlled by the hippocampus (long-term potentiation).
Since the hippocampus receives impulses from almost all areas of the cerebral cortex, all impressions of consciousness pass through it. Specific cells of this part of the limbic system (so-called pyramidal cells) also have a spatial memory. The perception of exactly where a person is currently located is therefore also controlled by the hippocampus.
Furthermore, the hippocampus serves as a kind of news detector. Novel information that passes through this structure is immediately prepared for storage. Known information, on the other hand, can be recalled and networked.
