Emotions, from a neuropsychological perspective, are defined as a response to environmental issues based upon a person’s individual appraisal of a situation and how they feel, based upon historical or situational events or memories (Andrewes, 2002). This is furthered with the contribution of mood, which is considered to be a temporary influence on how an individual views situations. Emotions can be explained in terms of internal affects, in which subjective feelings are thought but not necessarily expressed, and external affects, in which emotions are displayed to others and not kept inside internally. The external display of emotions can be demonstrated in the form of facial expressions and can be measured in a scientific experimental format when individuals are exposed to positive or negative stimuli (Papa & Bonanno, 2008).
The evolution of the brain from reptilian, to limbic, to neomammalian describes how emotions, which are challenging to measure or identify physiologically, are a part of our “brain blueprint” and differentiate us from primitive species (Andrewes, 2002). This has resulted in our ability to have behavioral responses that can manage fearful situations, protect our young, and induce or inhibit aggressive behaviors when managed by neurotransmitter activity.
Anatomically, the process of an emotional response is characterized first by a stimulus which triggers the appraisal process in the polymodal association area, the medial nucleus of the thalamus, and the inferior colliculus (Andrewes, 2002). This in turn triggers the lateral amygdala which signals the basolateral and basomedial amygdala and the central amygdale. The central amygdala, upon processing the input, initiates an emotional response in the hypothalamus (and then the pituitary gland) or the brain stem. This system of emotional response has been documented in both normal and bipolar patients and, bipolar patients are noted to have increased activity in the amygdala in comparison to non-bipolar patients when experiencing mania (Gruber, Johnson, Oveis, & Keltner, 2008).
Andrewes, D. (2002) Neuropsychology: From theory to practice. New York: Psychology Press.
Gruber, J., Johnson, S. L., Oveis, C., & Keltner, D. (2008). Risk for mania and positive emotional responding: Too much of a good thing? Emotions, 8(1), 23-33.
Papa, A. & Bonanno, G. A. (2008). Smiling in the face of adversity: The interpersonal and intrapersonal functions of smiling. Emotion, 8(1), 1-12. WW