Brain Function, Emotions, Stress, and Language in Psychology

Introduction: The Brain and Psychology

Understanding the function of the human brain is critical to understanding how and why people think and act the way they do. Studying the brain can also explain many different types of behaviors — such as emotions, stress responses, and the development of language — all of which are extremely useful in the study of physiological psychology.

The Frontal Lobe, Limbic System, and Emotions

The brain is divided into four sections called lobes. Emotions are associated with the frontal lobe, along with reasoning, movement, planning, parts of speech, and problem solving. The neurological pathways associated with perceiving and producing emotions arise from two distinct pathways. Two scientists found that "the first pathway connects the prefrontal cortex, the brain's emotional command center, to the nucleus accumbens, a region linked primarily to positive emotion; the second connects it to the amygdala, which is linked primarily to negative emotion" (Editors, 2008).

Studies have shown that people can "turn off" their negative emotions by thinking about other things, and that seeing and feeling something can trigger emotional responses in the brain. Research also indicates that damage to the frontal lobe — especially in children — can produce a lack of normal emotional functioning or a negative emotional disposition, leading to deviant emotions in some individuals. The frontal lobe is located within the limbic system, which also contains structures such as the hypothalamus, the septum, and the hippocampus. Scientists have described the limbic system as the control center of the entire brain.

Stress and Neuroanatomy

Stress can have a very negative effect on neuroanatomy and a person's behavior. The limbic system is highly involved in stress and the reaction to it, precisely because it serves as the brain's control center. There is a human stress response that is triggered in the brain and guides a person through stressful situations. These triggers follow a neurological pathway that activates the locus ceruleus, limbic nuclei, and hypothalamic nuclei, generating feelings of "fight or flight" that shape subsequent behavior.

Stress can change behavior and affect neuroanatomy by triggering certain reactions and thought processes. Each brain perceives stress differently, which is why people react differently to stressful events — some events are remembered as more significant or threatening and therefore elicit stronger responses. Research confirms that stress literally alters brain function: "Cognitive activation studies indicate increased amygdalar and decreased medial prefrontal cortical responding to threat, and impaired responding in rostral anterior cingulate cortex to emotional tasks" (Taber & Hurley, 2009). Other studies show decreased volume in areas of the limbic system such as the hippocampus. This means the brain functions differently under stress, and these changes can have long-term consequences for the mental health of individuals under significant or chronic stress.

Conclusion

Other types of aphasia resulting from brain damage reveal further complexity in language processing. In some cases, patients can only repeat sentences but cannot generate them; in others, they cannot repeat sentences they have just heard. All of these aphasias help physiological psychologists understand the production and comprehension of language by revealing how different brain regions communicate — and what happens when that communication breaks down. They also demonstrate that multiple areas contribute to speech and language, and that damage anywhere along these networks can disrupt language and comprehension throughout the brain.