loader animation

Association Between Emotions And The Alpha Waves

 Jul 7, 2022
Frontal alpha asymmetry or FAA

An affective state of animals and humans which arise as a response is called emotion, which is to the perception of a situation and object. Emotion plays a key role in interpersonal communications and events. Emotions are a type of psycho-physiological process in which people have different blood pressure, heart rates, brain activities and peripheral vascular resistance responses in different emotional states. Asymmetrical frontal cortical activity is of very much interest among these psycho-physiological responses. Frontal alpha asymmetry or FAA is the main indicator of asymmetric brain activity in the frontal cortex, which is responsible for asymmetrical anterior electroencephalographic activity in the alpha band which falls between 8–13 Hz. Alpha power which is oppositely related to regional brain activity. The lower power values of the alpha band suggest an increase in hemispherical or cortical activation. Frontal alpha asymmetry has a correlation with emotions with inconsistency in direction. There is one key neurophysiological model, the valence model, which accounts for the association between emotions and this alpha asymmetric pattern.

The Valence Model: The valence of emotion or the hedonic tone of personally experienced emotions. These are of two types, negative or unpleasant emotions (fear, sadness, anger, disgust) or positive or pleasant emotions (happiness, amusement, joy, contentment). According to this model, all emotions can be grouped as positive emotions or negative emotions. From this point of view, lower alpha power or greater left hemisphere activity is associated with positive emotion, whereas negative emotions are associated with greater right hemisphere activity. It was observed from EEG recording that, during a stable and resting period, greater left frontal activity was found to be related to conditions-like positive affects, on the other hand greater right frontal activity was found to be related to condition-like negative affects. Resting Frontal alpha asymmetry is also associated with emotive responses.

After recording resting EEG activity and extracting alpha power asymmetry, left hemispherical activation was found relevant to increased generalized positive emotion.  Studies also suggested that situational manipulations of negative and positive emotional states were associated with various asymmetric frontal activities. Research studies have also found that facial expressions of fear or anger were related to left frontal activity than overall controlled expressions. Kline found that sweet and pleasant smells significantly trigger greater left-hemispheric activity. it was established for users that stronger activation in the left hemisphere of the brain when watching pleasant or beautiful advertising and, oppositely a stronger activation in the left hemisphere which is associated with unpleasant or bad advertisements.

It has been reported that anger which is general a negatively valenced emotion, evoke behavioral tendencies of approach and also motivation linked approach. Multiple studies found that, higher anger scale score is associated with lower right frontal activity and higher resting levels of left frontal activity. Almost similar results were also seen in the state-induced anger. It is important to keep in mind that, some of the anger contexts are associated with withdrawal tendencies and activity in the right frontal cortex.

On the other hand, tenderness is tagged as a positive emotion, which is obviously different from anger emotion on the valence dimension. most of the studies have concentrated on basic positive emotions such as joy and happiness. However, little research has focused on tenderness (a affirmative emotion), which is associated with warmhearted and tender feelings. Tenderness is defined as a momentary experience which corresponds to love and care giving. Now see, when you look in the large eyes of a puppy or infant, you will definitely experience different feelings of tenderness. Tenderness is considered as an emotion which is closely related to joy and love, and also it has been verified as a typical emotion with individual, distinctive and subjective experience.