The Functions of the Limbic System

During brain development, beginning in the womb into adulthood, all of these cells must be grouped and organized into specific networks, which create the architecture of the brain (Perry & Szalavitz, 2006). The brainstem, the diencephalon, the cortex and the limbic system are the four major parts of the brain. The brain is organized from the inside out, thus, “the lower and most central regions of the brainstem and diencephalon are the simplest” (Perry & Szalavitz, 2006, p. 21) and are also the first to form, therefore, developing first as the child grows and develops (Perry & Szalavitz, 2006). As the brain develops upward and outward, the limbic system becomes more complex and the cortex is the crowning achievement of the brain structure (Perry & Szalavitz, 2006). These four areas of the brain are organized from top to bottom and inside to outside, although these four areas are interconnected, each one controls different functions such as the brainstem controls body temperature, heart rate and blood pressure, as well as respiration. The limbic system and diencephalon control emotional responses that help to guide one’s behavior such as fear, love, joy and anger. The cortex, the top part of the brain, regulates the complex and high functions such as speech, critical thinking, and decision-making (Perry & Szalavitz, 2006). The

To coordinate with our current chapter on emotions, our class watched the film Inside Out. The story was about the emotions, Joy, Sadness, Anger, Fear, and Disgust, controlling a goofy, honest, and caring 11 year old named Riley. Inside her brain, the emotions used controls to decide the way Riley feels. The part of the brain the “control center” in Inside Out represented was the Limbic System. I know this because during in our Body and Mind unit, the part of the brain we most associated with mood and emotions was this system. It is best defined as a complex system of nerves and networks in the brain, including areas concerned with instinct and mood. The Limbic System’s main control is emotions and drives feelings, which was the main purpose of the emotions “control center.”

The limbic system (or Paleomammalian brain) is a set of brain structures including the hippocampus, amygdala, anterior thalamic nuclei, and limbic cortex, which support a variety of functions including emotion, behavior, long term memory, and olfaction.[1] The term "limbic" comes from Latin limbus, loosely translating as "border" or "belt".

These psychological disorders originate from different area of the brain. The brain consists of three main parts: the forebrain, midbrain, and hindbrain. The forebrain is made up of the cerebrum, thalamus, and hypothalamus (part of the limbic system). The midbrain comprises the tectum and tegmentum. The hindbrain consists of the cerebellum, pons and medulla. The midbrain, pons, and medulla in conjunction are typically called the brainstem.

2. The limbic system also includes the amygdala(Amig- Dalah) which is the part of the brain responsible for emotions. In an Article called Scientists Discover Why Dreams Are So Weird they state “During REM sleep, the men's brains showed the most activity in the limbic system, a primitive part of the brain that governs emotion. Meanwhile, little activity was seen in the frontal lobes. The frontal lobes help sort out and give meaning to information from the senses. According to the researchers, this unequal activity might explain why dreams can be so intense, yet so illogical. It may also explain why dreams do not seem strange to the dreamer while they are happening” (Scientists Discover Why Dreams Are So Weird).

The amygdala specializes in threat detection, fear, excitement, and arousal, hippocampus helps format long-term declarative memories and spatial reasoning. The anterior cingulate cortex influences autonomic function, decision making, error detection and emotion while the posterior has a role in spatial annotations memory. The septal area produces pleasurable feeling,

Studying parts of the brain that are involved in dealing with fear and stress also helps researchers understand possible causes of PTSD to begin formulating a plan to treat PTSD. The amygdala is known for its role in emotion, learning, and memory. The amygdala appears active in learning to fear an event as well as in the early stages of fear extinction. In storing extinction memories and dampening an existing fear the prefrontal cortex, which is involved in problem solving, decision making, and judgement, is seemingly

The brain develops in such a way that it leaves itself vulnerable to these negative influences. The prenatal brain develops an overabundance of neurons, some of which are then carefully eliminated before age 4 (5). In a process similar to this, the amount of synapses between neurons is built up during early childhood and then pruned back for the next 30 years of life (5). These two processes are both disturbed by elevated levels of stress hormones (5). The two centers of the brain with the most postnatal changes, including the growth of new neurons after birth, are the hippocampus, which is part of the limbic system, and the cerebellar vermis (6). The hippocampus is in charge of creating and retrieving memories, working together with the other parts of the limbic system, such as the amygdala, which records the emotions for each memory. The vermis controls the production and release of two of the catecholamine neurotransmitters, dopamine and norepinephrine (6). Both the vermis and the limbic system have higher concentrations of receptors for the stress hormone cortisol than anywhere else in the brain (6). Due to this fact, these still-developing areas are the most vulnerable to the damage done by elevated levels of stress hormones.

In addition, the limbic system is responsible for our perception of other emotions, both positive and negative, which explains the mood altering properties of many drugs. The cerebral cortex is divided into areas that control specific functions. Different areas process information from our senses, enabling us to see, feel, hear, and taste. The front part of the cortex, the frontal cortex or forebrain, is the thinking center of the brain, it powers our ability to think, plan, solve problems, and make decisions.

In Chapter 8 “Where the Wild Things Are,” the author Le Doux looked at the how our brain regions and systems functioned during the development of anxiety disorders. He introduced many researchers’ ideas and theories such as Pavlovian conditioning and instrumental conditioning; then, he listed the brain regions that were associated with anxiety and fear conditioning such as hippocampus, amygdala, sympathetic nervous system, and various brain cortexes. He also explained how our brain became conditioned for different anxiety disorders.

This region mediates motivational behaviors, emotions states, and memory processes. The limbic system also regulates body temperature, blood pressure, and blood sugar level. The hippocampus is a part of the limbic system that plays an important role is emotions, learning, and memory. Amygdala also plays an important role in the limbic system, it helps regulates aggression, eating, drinking, and sexual behavior. Another main region in the limbic system is the hypothalamus, it monitors levels of glucose, salt, blood pressure, and hormones. The hypothalamus also helps regulate processes in the body through its connection to the central and autonomic nervous system and

The parabrachial nucleus is a center for regulation of physiologic manifestations of fear avoidance and anxiety 83. These connections develop information about whole body rotation and position with respect to gravity. This information is linked to threat assessment pathways via connections between parabrachial nucleus and the central nucleus of the amygdala 85. Connections between amygdala and superior colliculi and between amygdala and thalamus link visual and somatosensory inputs to threat assessment pathways 86. Sensory inputs and assessment of threat converge in the hippocampus, dorsolateral prefrontal cortex, the insula, and anterior cingulate. These four structures are components of both the limbic and the vestibular cortex 87. Vestibuloparabrachial network and amygdala-locus coeruleus outputs

Emotion and memory are actually very closely related. Thus, it is not surprising that the hippocampus is located in the limbic system, which is the emotion system portion of the brain. The limbic system is mainly associated with memory, motivation, and emotions (Memory). The hippocampus itself is located within the temporal lobes, right next to the amygdala. The structure is a horseshoe shaped paired brain structure, where one half of it is located in the left brain hemisphere, while the other half is in the right brain hemisphere (Robson).

The hippocampus is part of the limbic system that controls the emotions and autonomic nervous system. The hippocampus controls long-term and short-term memory. It is located in the medial temporal lobe of the brain behind the Amygdala (Hayhurst, 2002). The hippocampus links memory and emotion together,

The limbic system was first recognized due to Franz Josef Gall (LeDoux, J., 1996). Franz Joseph Gall developed the idea of “phrenology” that focused on the study of the different variations of bumps on the human skull to be related to differences in behavioral and emotional functioning. The limbic system’s main function in the brain is to control emotional behaviors and certain forms of memories that are infused with emotion (amygdala). The amygdala is a part of the brain that forms the tail end of the basal ganglia within the rostral temporal lobe and is located near the hippocampus (Lambert, K.G. & Kinsley, C .H., 2005). The amygdala, as defined by the text, is an almond-shaped structure that functions as a part of the limbic system involved in regulation of emotion and sexual urges (Lambert, K.G. & Kinsley, C .H., 2005). In addition, the amygdala is comprised of a dozen or more sub regions that are not all involved in fear conditioning (LeDoux, J., 1996).