Introduction and Theoretical Basis for Research
Emotional expressions are a way of communicating one's feelings to others. Facial expressions are one way of communicating internal feelings. Whereas an individual's smile indicates a feeling of joy or happiness, a frown is considered an expression of sadness. Another mode of emotional expression involves speech. The tone of someone's voice may convey a feeling of anger or excitement. Gestures and bodily postures represent a third way of communicating feelings. When someone clenches a fist, it usually indicates anger. A sad person often holds their head and eyes in a downward position. Someone who is excited might jump up and down.
Since emotions are a way of communicating one's feelings to others, they are part of the social process. Individuals may approach or avoid another person based on the emotional expressions they observe. People are more likely to approach someone who is smiling rather than someone who looks angry. Even people who do not speak the same language can understand each others' emotional expressions. (1) For infants, emotional expressions provide an important mode of communicating with others, especially before they develop conventional language. (2) When infants cry, people know that something is wrong. Yet, can they tell whether infants are feeling anger or sadness?
An Ethological Approach
There are different theories that explain how emotions develop during infancy. Developmental theories of emotion focus on changes in emotions over time. An ethological perspective places great importance on evolutionary influences upon emotional behavior and development. One such perspective, differential emotions theory, emphasizes the physiological influences on emotional behavior due to evolutionary influences on the nervous system. This approach draws on the work of the natural scientist Charles Darwin which describes the anatomy of facial expressions in man and animals. Differential emotions theory posits that basic emotions (joy, anger, fear, surprise, disgust, sadness, interest, and contempt) stem from specific neural circuits that are activated and result in specific facial expressions. Basic emotions are elicited by particular situations/events and serve unique adaptive functions. (3) For example, joy is elicited by the sight of a loved one approaching. That smile indicates that it is acceptable to continue to approach, resulting in social interaction. Continued joyful social interaction over time strengthens the social bond between individuals. (4)
Early social relationships are necessary for survival; emotions play an important role in maintaining these relationships. (5) An infant's facial expressions communicate basic emotions, each of which serves a unique adaptive function. Basic emotional expressions are the first form of communication between infants and adults. Joy is expressed through smiling and playful behavior (i.e., peek-a-boo). It strengthens the bond between the infant and the individual responsible for eliciting this emotion. (6) Interest is evident in an infant's attention (i.e., looking at someone). By focusing attention on another person, the emotion of interest helps the infant to engage in social interaction with that individual. (7) Sadness is evident in a frown, crying, and whimpering. Such behavior elicits caregiving behavior (i.e., hugs, kisses) from an adult which strengthens the bond between the infant and the caregiver. (8) Caregivers thus infer what infants feel from their emotional expressions. While these facial expressions of basic emotions are early forms of communication, all of them are not immediately evident at birth.
Development of Emotions During Infancy
According to differential emotions theory, discrete (basic) emotions emerge during infancy according to a predictable timetable, and their development is strongly influenced by neurophysiological maturation. …