Why study the limbic system?
Most people see emotions and motivation as a psychological issue that originates in the mind. However, modern neuroscience offers an explanation for emotions and behaviors that point to primitive centers of the brain as the originators of emotional reactions. Emotions themselves are protective mechanisms designed to prompt an appropriate reaction in threatening situations (Koscik &Tranel, 2011, 137).
The limbic system is responsible for emotion, motivation, long-term memory, the processing of olfactory information and behavior (Adams & Victor, 1985). While it is primarily responsible for emotions and emotional processing, it also is involved in the formation of memories. For example, when an individual smells a comforting scent such as cinnamon or the smell of pumpkin pie, the limbic system creates the emotional response that has been learned from early years. The behavior that is triggered from this memory is salivation which triggers other digestive processes that create hunger. The function of the limbic system is important in understanding human reactions, behaviors, and reasoning. This paper will make the case that the emotion domain of human beings is primarily a biologically produced experience.
Use your promo and get a custom paper on
"Biology and Traits: the Limbic System".
Structure of the limbic system
The limbic system is not a single brain structure but a set of structures that lie on both sides of the thalamus directly under the cerebrum. It is a collection of multiple structures including the telencephalon, the diencepahlon, and the mesencpehalon. Other structures that are part of the limbic system are the hippocampus, the amygdala and the limbic midbrain.
The system itself is made up of four components that create two c-shapes. The first encompasses the hippocampus and the fornix. The second encompasses the cingulate and parahippocampal gyri. It also has structures that are located in the cerebral pre-cortex and sub-cortex of the brain. These structures are important in the production and mediation of signs and symptoms that are often associated with some mental disorders (Adams & Victor, 1985)
Function of key structures within the limbic system
The hippocampus is strongly involved in the memory function of the brain (Markowitsch & Staniloiu, 2011, 722). It plays a role in moving information that is stored in short term memory into long term memory. Damage to the hippocampus causes an individual to be unable to build new memories. The individual may be able to remember information that was stored prior to the onset of the injury but can remember nothing after.
The amygdalae are two masses of neurons that rest on either side of the thalamus. They serve a function in alerting the cortex to information and stimuli that are motivating such as a potential reward of threat. They also are involved with triggering the hippocampus to hold onto details of a situation.
The memory function of the hippocampus was discussed earlier in this paper. The amygdala is also involved in episodic -autobiographical memory. Episodic memory is the memory of personal events and the associated emotions ( Eichenbaum, 2007, 48-50). It is made up of recollections of experiences that happened at a specific time and p It is the collection of past personal experiences that occurred at a particular time and place. The amygdala encodes, stores, and retrieves these personal memories. Because these memories include memory of the associated emotions, memories of events can include the cues that trigger an emotional response. The amygdala is also involved in the processing of social information (Spreng; Mar ,2012, 47). , specifically the recognition and evaluation of facial expressions (Rule,Moran, Freeman, Whitfield-Gabrieli Gabrieli, & Ambady, 2011, 735).
Conclusion
Earlier studies into the functions of the brain derived conclusions about the functions of various parts of the brain by researching the functions that were lost after an injury to a known area of the brain. Modern research has benefitted from new advances in technology that allow for the tracking of electrical impulses throughout the brain (Robert & Isaacson, 1992,130).
Studies of individuals who have known damage to the limbic system have shown significant problems with memory with losses that resemble the situation presented in the movie “50 First Dates”. However, individuals have also displayed extreme emotionality that may be unrelated to the circumstances that are occurring at the time. They also have problems reading the intent of other individuals. These studies clearly demonstrate the biological component of emotion that is regulated by the brain itself. Nonetheless, the human brain has the capacity to respond to the volitional commands of human cognitions regulated by the frontal lobe. The human brain is an amazing organ that integrates the functioning of all its parts to create the full dimensions of the human experience.
- Adams, R.D. and Victor, M., Principles of Neurology, 3rd edn., MacGraw-Hill, New York, 1985.
- Eichenbaum, H, “Comparative cognition, hippocampal function, and recollection”. Comparative Cognition & Behavior Reviews 2 (1): 47-66, 2007.
- Isaacson, R.L. “A fuzzy limbic system”. Behavioural Brain Research 52 (2): 129-131, 1992
- Koscik, T.R.; Tranel, D.”The human amygdala is necessary for developing and expressing normal interpersonal trust”. Neuropsychologia 49 (4): 602-611, 2011.
- Markowitsch, H.J.; Staniloiu, A “Amygdala in action: Relaying biological and social significance to autobiographical memory”. Neuropsychologia 49 (4): 718-733, 2011
- Rule, N.O.; Moran, J. M., Freeman, J. B., Whitfield-Gabrieli, S., Gabrieli, J. D. E., , & Ambady,N . “Face value: Amygdala response reflects the validity of first impressions”. NeuroImage 54 (1): 734-741, 2011
- Spreng, R.N.; Mar, R. A. “I remember you: A role for memory in social cognition and the functional neuroanatomy of their interaction”. Brain Research 1428: 43-50, 2012.
