Hippocampus And Its Role In Memory Formation

Do you know what hippocampus and the what role it plays in the human body? Well, this article is all about that.

The hippocampus is a major component of the brain located in the inner folds of the bottom middle section of the brain called the temporal lobe. The name hippocampus comes from the Greek words 'hippo' meaning horse and 'kampo' meaning monster.

Hippocampus is one of the most studied parts of the brain which plays an important role in the limbic system. It is involved in the formation of new memories and is also linked to learning and emotions.

What Are The Functions Of Hippocampus?

The functions of hippocampus are associated with feeling and reacting. The hippocampus plays a key role in the limbic system which is situated on the edge of the cortex and it includes the amygdala and hypothalamus.

These structures aid in controlling the different body functions such as the endocrine system, memory and regulates emotions.

The hypothalamus is a portion of the brain that constitutes of a number of small nuclei with a variety of functions which include linking the nervous system to the endocrine system via the pituitary gland. And the amygdala is responsible for moods, emotions and other functions related to depression and anxiety.

How Does Hippocampus Affect Memory?

Hippocampus plays a critical role in the formation, organization and storage of new memories and interlinks certain sensations and emotions to these memories.

Researchers have found that the different subregions of the hippocampus play an important role in two types of memory - declarative memories and spatial relationship memories.

• Declarative memories are the ones that are related to events and facts that can be constantly recalled. Declarative memory is sometimes called explicit memory. Examples of this memory are learning how to memorize speeches in a play, or knowing that your favourite restaurant closes at a certain time.
• Spatial relationship memories involve remembering different locations and spatial relation between objects. For example, navigating through a route. This type of memory is stored in the right hippocampus.

Also, hippocampus is the place where short-term memories are converted into long-term memories.

What Would Happen If The Hippocampus Is Damaged?

As hippocampus plays an integral role in the formation of new memories, even a small damage to the hippocampus can have a serious long-term impact on certain types of memory. It can also result in anterograde amnesia which means the loss of ability to form new memories.

Research says that if the left hippocampus is damaged, it has an effect on the recall of verbal information and if the right hippocampus is damaged, problems arise in the recall of visual information.

Furthermore, MRI scans of human brains have shown that between the age of 30 and 80, the hippocampus shrinks by 13 per cent. A damage to the hippocampus can make it harder for a person to remember how to get from one place to another, finding a new store and many such things.

Diseases That Affect The Hippocampus

1. Alzheimer's disease - You may be wondering how the Alzheimer's related to hippocampus? Well, research has found that hippocampus is one of the first areas in the brain to get affected by Alzheimer's disease. This explains the early symptoms of Alzheimer's disease which are the impairment of memory and having difficulty in following directions.

2. Temporal lobe epilepsy - Around 50 to 75 per cent of people with epilepsy suffer damage to the hippocampus.

3. Stress and depression - In people who suffer from chronic depression, the hippocampus starts to lose volume. Stress too has a negative effect on the hippocampus.

4. Transient global amnesia - Research says that punctuate lesion in the hippocampus (identified through MRI) can be linked to transient global amnesia.

5. Schizophrenia - Evidence also suggests that the hippocampus is disrupted in people with schizophrenia. This is due to the fact that people with schizophrenia also have problems with their memory.

Share this article!