Brain is a very complex organ that control our whole body. When it comes to the controlling of emotions, there are different parts in brain that are responsible for it. Emotions are basically the reactions and feelings that human beings experience in response to any situation. There are six basic emotions that humans experience. these are:Joy, sadness, surprise, anger, fear, disgust.
To control all of these emotions, there is an area in our brain known as limbic system which is responsible for it. Functioning of Limbic System is usually associated with 5F’s i.e.,
- Forgetting [Memory]
- Feeding [Hunger]
- Fighting [ Emotional Response]
- Family [Sexual Reproduction, Maternal instincts]
- Fornicating [Sexual Arousal]
Limbic system is able to perform all these activities through connections with different part of the brain. It is further divided into two parts: cortical and subcortical components. The cortical component consists of:
- Orbitofrontal cortex: It is a part of prefrontal cortex that sits above the orbits. It is present at the front of brain and have extensive network with all the sensory areas and limbic system. It is mainly associated with the decision-making ability of a person. Therefore, people who have damage in orbitofrontal cortex often find it difficult to decide and compare values of things with other options. It is also associated with the perception of smell and formation of memories.
- Hippocampus: Hippocampus is a small area located deep within the temporal lobe. It is a part of limbic system which mainly has three functions, which are forming new memories, learning and emotions. It is associated with Long Term Memory. It helps to connect the memories with the emotions attached to the memories when they were first formed.
- Cingulate gyrus: The cingulate gyrus is the part of cerebrum region closest to the limbic system, located just above the corpus collosum. It connects the thalamus to the hippocampus and appears to be responsible for focusing attention on emotionally significant events as well as associating memories with smells and pain. This region is also involved in the emotional response to pain and the regulation of aggressive behaviour. It is responsible for the perception of neuropathic pain.
- Para hippocampal gyrus: It is present in the temporal lobe and surrounds the hippocampus. It has role in both navigation and spatial memory. It provides a path of communication between hippocampus and all cortical areas through which afferent impulses enter hippocampus.
The subcortical components consist of:
- Amygdala: The amygdalae are the two almond-shaped masses of neurons which are located at the either side of the lower ends of the hippocampus. It is known as emotional center of the brain. It helps the body to identify emotions and prepare the body for fight and flight situations. It is also responsible for learning on the basis of rewards and punishment.
- Olfactory bulb: It is a round mass of tissue that contain nerve calls which are responsible for the smell. They are present at the bottom side of the brain.
- Hypothalamus: The hypothalamus, a structure deep within your brain, serves as your body’s intelligent control and coordination center. Its main function is to keep the body in a stable state known as homeostasis. This is achieved either by directly affecting the autonomic nervous system or by controlling hormones.
- Thalamus: The thalamus is the information relay station of the body. All information from your body’s senses (excluding smell) must be processed by your thalamus before being transmitted to your brain’s cerebral cortex for interpretation. Your thalamus is also involved in sleep, alertness, consciousness, learning, and memory.
All the areas of limbic system mentioned above has different roles and many of them control basic emotions. So, the main area associated with different emotions are:
- For fear: Amygdala
- For sadness: amygdala
- For happiness: precuneus
- For love: hypothalamus
- For surprise: hippocampus
- For anger: Amygdala
Limbic system disorders
Damage to limbic system leads to several disorders and defects. For example, damage to amygdala region would lead to defects in person’s fear processing. He will engage in more risk taking and dangerous behaviors. Defects in hippocampus can lead to defects in learning processes.
Also, there are many cognitive disorders that can result from the defects in limbic system. Such as:
- Olfactory impairments
- Obsessive compulsive disorder
- Posttraumatic stress disorder
- Bipolar disorder
- Autism spectrum conditions
- Alzheimer’s disease
- Movement disorders – Huntington’s and Parkinson’s disease
To deal with these type of problems, one need to consult a psychiatrist and psychologist at the earliest possible.