In modern neurobiological terms, emotions
are complex programs of actions triggered by the presence of certain
stimuli, external to the body or from within the body, when such stimuli
activate certain neural
systems. Feelings of emotion, on the other hand, are perceptions of the
emotional action programs. The (1) triggering systems, the (2) neural
systems which execute the action program, and (3) the actions whose
ensemble constitutes each emotion, were selected over evolutionary time
and become available to each organism of a given species early in
development thanks to that organism’s genome.
The emotions are as ubiquitous in daily life as vision, or hearing, or touch, but only recently have they received due consideration from the brain
sciences. Perhaps for that reason they have been the object of many
misconceptions. For example, the word emotion is usually taken to mean
both a specific pattern of behavior (the emotion, in the proper sense)
and a mental state related to it (known as feeling). Moreover, it is
often thought that the emotion proper is triggered by a feeling that
precedes it. Current research indicates, however, that “emotions” and
“feelings of emotion” are distinct aspects of a functional sequence that
begins when an object or situation triggers a specific behavior — the
emotion — which is followed rapidly by the perception of the changes
related to the behavior — the feeling of emotion. Relative to the
triggering cause, the functional sequence begins with actions and
culminates in perceptions. The word emotion should be reserved for the
behavioral component of the sequence; it should not be used to designate
the feeling component.
Another misconception concerns the idea that emotions are
irrational disruptions of consciously directed behavior. However,
emotions are not necessarily contrary to reason. They are best seen as
older forms of reason, assembled by biological evolution and not by conscious
deliberation. They operate automatically and only in response to
certain classes of circumstance. They are not the result of thinking
through a problem and generating a solution (for background see Darwin,
1873; de Sousa, 1990; and Nussbaum, 2003).
Throughout evolution emotions have been instruments of life
regulation, that is homeostasis. Emotions contribute to the survival and
well-being
of individuals and groups by providing organisms with a swift,
automated means to circumvent dangers and take advantage of
opportunities. This is true of animals and humans. In humans, however,
emotions can clash with culturally acquired conventions and rules, in
which case they may indeed be disruptive and less adaptive than
consciously deliberated responses. In brief, although emotions have
helped shape ethical behavior in the course of evolution, they are not a
substitute for decisions informed by ethics (Damasio, 2003; Damasio,
2007).
The deployment of an emotion accomplishes several benefits to the
emoting organism. The emotional action-programs achieve those benefits
by producing extensive functional changes in varied sectors of the
organism — for example, in the musculature of the viscera and of the
skeleton, and in the chemical profile of the internal milieu — and by
causing the organism to execute certain preset behaviors. Examples of
muscular changes include tachycardia or brachycardia, gut contraction or
dilation, and specific facial expressions and postures. Changes in the
internal milieu can come from releasing chemical molecules into the
bloodstream, as happens with the hormone cortisol in the case of fear.
As for behavioral changes, the examples are numerous. The movements that
lead an organism to concentrate on the object that triggered the
emotion, whose ensemble is known as attention,
and which results in the enhanced mental salience of the object, are
present in most instances of emotion. The engagement of specific
behaviors such as freezing in place, fleeing from a threat, or
nurturing, are good examples of complex and specific behaviors that are
part and parcel of the action-program of a certain emotion.
The range of emotions is wide but finite. In humans it includes
the programs of fear, disgust, sadness, joy, anger, and surprise, as
well as a group of simpler programs such as enthusiasm or
discouragement, known as background emotions. It also includes a group
of very complex programs, usually known as social emotions, such as
embarrassment, shame, guilt, contempt, compassion, and admiration.
The triggering of each emotion requires the presence of an
appropriate stimulus, an emotionally-competent stimulus, which initiates
the execution of the actions in the program. The execution of each
emotion is quickly followed by the respective feeling state provided the
brain is complex enough to permit the mapping of internal states and a
minimal level of consciousness. In situations in which there are
multiple emotional-competent stimuli and multiple resulting feelings,
the neat sequence of emotion to feeling may appear to be blurred.
