The Nature of Emotions

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Emotion appears to be a key component in the behavior of conscious beings. To some extent, consciousness "is" emotion. There is probably no recollection, no thinking and no planning that occurs without feeling emotions. We are either happy or sad or afraid or something else all the time. There is rarely a moment in our day when we are not feeling an emotion. William James conceived mental life as a "stream of consciousness", each state of consciousness possessing both a cognitive aspect and a feeling aspect.

Whether all of consciousness is just emotion or whether emotion is a parallel, complementary facility of the mind, is debatable. But it can be argued that we would not consider conscious a being who cannot feel emotions, no matter how intelligent it is and no matter how much its body resembles ours.

On the other hand, we ascribe emotions to beings that we don't consider as "conscious": dogs, birds, even fish and tarantulas. Are the intensities of their emotions (of fear, for example) as strong as ours, regardless of whether their level of self-awareness is comparable to ours? Is emotion a more primitive form of consciousness, that in humans developed into full-fledged self-awareness? Is emotion an organ, just like feet and tails, that a species may or may not have, but which has no relevance to consciousness?

When turning to emotions, the first problem facing us is that most studies on them are from a psychological perspective. Little research has been done from a more scientific, biological perspective.

Emotions have been traditionally neglected by scientists researching the mind, as if they were a secondary aspect (or simply a malfunction) of the brain activity. The fact is surprising because emotions have so much to do with our being "aware", with differentiating intelligent life from dead matter and non-intelligent life. While the relationship between "feeling" and "thinking" is still unclear, it is generally agreed that all beings who think also feel. That makes feelings central to an understanding of thinking.

That emotions may not be so peripheral a notion as the scant literature on them would imply is a fact suspected since ancient times, but only recently science has focused on their function, their evolution and their behavior. In other words: how did the ability to feel emotions originate, why did it originate and how does it influence our mind's overall functioning?

Emotions as Survival Instinct

The answers can be summarized, once again, as: emotions are a product of evolution, they exist because they favor our species in natural selection. What emotions seem to do is help us make fast decisions in crucial situations. If I am afraid of a situation, it means that it is dangerous: the emotion of fear has already helped me make up my mind about how to approach that situation. If I were not capable of fear, my brain would have to analyze the situation, infer logically what is good and what is bad in it for me, and finally draw a conclusion. By that time, it may be too late. Fear helps act faster than if we used our logical faculties.

George Mandler had a powerful intuition. Let's assume that, of all the information available in the environment, the mind is mainly interested in environmental regularities. Then most of its processing can be reduced to: there is a goal (e.g.: "eat"), there is a need (e.g.: "food") and there is a situation (e.g.: "a plantation of bananas"). Based on known regularities of the environment, the mind can determine what it needs to achieve its goal in the current situation. The emotion (e.g.: "desire bananas") simplifies this process. The function of emotions is to provide the individual with the most general view of the world that is consistent with current needs, goals and situations.

Besides, emotions are also the fastest way that we can communicate with members of our group. The American psychiatrist Allan Hobson thinks that emotions are signals between animals of the same species that communicate one's brain state to another.

Emotion as Rationality

Aaron Sloman has reduced the argument about emotions to simple mathematical terms. Let us look at an "agent" (whether a human, an animal, a robot or a piece of software), which is limited and intelligent and must act in a complex environment. A "complex" environment may well include a very large number of factors. In fact, it may be made of an "infinite" number of factors, if one starts counting every little detail that may have an influence. Our agent, which is limited, would never reach a conclusion on what to do if it blindly analyzed all factors. Therefore, in order to survive (to move at all, actually) it must be endowed with mechanisms that cause emotions. In other words, emotions are the result of constraints by the environment on the action of the intelligent being.

An emotional state is created by a situation, through a somewhat mysterious chemical reaction in the nerve system. A cognitive state is created by a number of situations and by a thinking process that relates those situations and draws some kind of conclusion. The relation between emotional states and cognitive states is reduced to the need to draw conclusions when cognition would face combinatorial explosion of possible reasoning threads.

Ronald DeSousa expresses this fact in a different way: emotions play the same role as perceptions, i.e. they contribute to create beliefs and desires. Beliefs and desires are necessary elements of any logical system: one attempts to satisfy desires by acting in the environment according to one's beliefs about the environment. DeSousa believes that emotions are learned like a language. And, like any language, they have their own grammar, i.e. their syntax and semantics (an idea also advanced by Sloman). Just like the meaning of words ultimately derives from the sentences in which they can be used, the semantics of emotions derives from the scenarios in terms of which they have been learned. Emotions can therefore be studied in a formal way just like any other language. The complementarity between reason and emotion becomes what he calls "axiological rationality", yet another way to express the fact that emotions determine what is salient, i.e. can restrict the combinatorial possibilities that reason has to face in the real world.

Emotion as Homeostasis

Ross Buck proposed a very elegant decomposition of human behavior. In his view, our behavior is the product of several systems of organization which belong to two big families. The first one is the family of innate special-purpose processing systems (reflexes, instincts, etc.). In general their function is "bodily adaptation" to the environment. In general, their approach is not analytic but holistic and syncretic: they don't "reduce" the situation to its details, they treat it as a whole. In Buck's view, these processes are innate, we don't need to learn them. The second family contains acquired general-purpose processing systems. In general their function is to make sense of the environment. Their approach is sequential and analytic. The former family is associated with the right hemisphere of the brain and is responsible for emotional expression; the latter is associated with the left hemisphere and is responsible for symbolic thinking. The two families cooperate in determining the body's behavior.

What is even more interesting about Buck's analysis is actually the advantage of emotions in communication between humans. Communication of emotions turns out to be a biologically shared signal system. It was created through the evolutionary process and it is part of every human being. It means that it is very easy to communicate an emotion: we immediately recognize the meaning of another human's emotion. On the contrary, communicating a theorem is not easy at all, and often requires special skills.

Besides bodily adaptation, therefore, emotions have the important function of speeding up communication of crucial information among members of the same species.

If emotion is, ultimately, a reaction to a situation in the environment, it can be assumed to be a "measure" relative to that situation, and what is communicated is precisely that measure. But a measure of what? Buck thinks that emotions always originate from motives that must be satisfied: the emotion is a measure of how far they have been satisfied. For example, fear is a measure of safety.

A more appropriate way of referring to adaptation is "homeostasis", which is the process of searching for a balance. If something changes in the environment, all the organisms that depend on that environment will react somehow to recreate the equilibrium they need to survive. This process of continuous search for equilibrium is called "homeostasis". Most scientists who have studied emotions agree with Buck that the ultimate function of emotions is homeostasis.

Emotion as Heterostasis

Harry Klopf is a notable exception. His view is just the opposite: organisms are not hiding in the environment, trying to minimize action and change; they actively seek stimulation. If homeostasis is the seeking of a steady-state condition, "heterostasis" is the seeking of maximum stimulation. According to Klopf, all parts of the brain are independently seeking positive stimulation (or "pleasure") and avoiding negative stimulation (or "pain"). Klopf also thinks that cognition and emotion coexist and complement each other, but their relative roles are significantly different: emotion provides the sense of what the organism needs, cognition provides the means for achieving those needs.

Emotion as Cognition

The common theme underlying all of these studies is that emotions are not as irrational as they seem to be; quite the opposite, actually.

Richard Lazarus has provided a synthesis of all of these themes. He agrees that the final goal of our emotions is to help the organism survive in the environment. Emotions arise from the relationship between the individual and its environment, or, better, the regularities of its environment. Emotion requires an appraisal of the situation and its consequences. For example,such an appraisal may lead to fear if the situation turns out to be dangerous. Emotions are genetically determined, but they can change during a lifetime: both biological and social variables may alter our set of emotions, and this explains why emotions change through the various stages of life.

Ultimately, emotions express the personal meaning of an individual's experience. The meaning of each emotion is about the significance of the triggering event (the situation) for the well-being of the individual.

Each emotion is defined by a set of benefits and harms in the relationship between individual and environment, and that set is constructed by a process of appraisal. Appraisal is key to emotion. Each type of emotion is distinguished by a pattern of appraisal factors.

Since appraisal is the fundamental process for the occurrence of emotion, Lazarus believes that cognition is a requisite for emotion: a cognitive process (an appraisal) must occur before one can have an emotion.

Emotion as Communication Between the Brain and the Self

All of these models tend to neglect the relation between emotion and awareness. They also tend to make too abstract the obvious relation between emotion and the body.

A synthesis that directly refers to consciousness and the body has been proposed by Jose Jauregui. Jauregui, like E.O. Wilson, views sociology as a branch of biology. In his opinion, the same emotional system controls social, sexual and individual behavior. Such emotional system originates from the neural organization of the brain: emotions are rational and predictable events. Jauregui believes that the brain is a computer, but introduced the novelty of emotions as the direct product of that computer's processing activity. It is emotions, not reason, that directs and informs the daily actions of individuals.

Jauregi begins by separating the brain and the self: the brain is aware of what is going on in the digestive system of the body, but will inform the self only when some correction/action is necessary. Normally, an individual is not aware of her digestive processes. Her brain is always informed, though. The communication channel between the brain and the self is made of emotions. The brain can tune the importance of the message by controlling the intensity of the emotions. Far from being an irrational process, the emotional life is mathematically calculated to achieve exactly the level of response needed. Feelings are subjective and inaccessible, but they also are objective and precise.

The self has no idea of the detailed process that was going on in the body and of the reason why that process must be corrected. The brain's emotional system, on the other hand, is a sophisticated and complex information-processing system. The brain is a computer programmed to inform the self (through emotions) of what must be done to preserve her body and her society. It is through emotions that the brain informs the self of every single detail in the body that is relevant for survival. There almost is no instant without an emotion that tells the individual to do something rather than something else. "For human beings the reality that ultimately matters is the reality of their feelings".

The self keeps a level of freedom: while it cannot suppress the (emotional) messages it receives from the brain, it can disobey them. The brain may increase the intensity of the message as the self disobeys it and a painful conflict may arise. The brain and the self are not only separate, but they may fight each other.

In conclusion, only the self can be conscious and feel, but the brain has control of both consciousness and feelings.

If we view the brain as a computer, the hardware is made of the neural organization. There are two types of software, though: bionatural (knowledge about the natural world) and biocultural (such as a language or a religion). A program has three main components: the sensory, the mental and the emotional systems. Any sensory input can be translated automatically by the brain into a mental (idea) or emotional (feeling) message; and viceversa. Both biocultural and bionatural programs exert emotional control over the body.

Jauregi distinguishes five systems of communication: the natural system (the sender is a natural thing, such as a tree), the cultural system (the sender is culture, something created by humans), the somatic system (the sender is the individual's own body), the imaginary system (the sender is imagination) and the social system (the sender is another individual). The human brain is genetically equipped to receive and understand all five kinds of messages. What ultimately matters is the emotional translations of sensory inputs.

Emotion as Body Representation

Similar conclusions are reached by the neurobiological studies of Antonio Damasio, who is focusing on the relation between memory, emotions and consciousness. What is novel about his approach is the distinction between emotions and "feelings". A feeling is a private experience of an emotion, that cannot be observed by anybody else. An emotion is the brain process that we perceive as a feeling. An emotion can be observed by others because it yields visible effects (whether the facial expression or a movement) and because it arises from a brain process that can be observed and measured.

The difference is crucial. Emotions are fixed genetically, to a large extent: evolution has endowed us with a basic repertory of emotions that help us survive. My personality (which is mostly shaped by my interaction with the environment) may determine how I express and react to those emotions, but the emotions that I feel are the same of my whole species. Emotion is a genetically-driven response to a stimulus: when that stimulus occurs (for example, a situation of danger), a region of the brain generates an emotion (fear) that is spread through the brain and the body via the nervous system and therefore causes a change in the state of both the brain and the rest of the body. This change of state is meant to somehow cope with the stimulus. Some emotions are acquired during development (eg, through social interaction) but they too are grounded in the universal, primary emotions of the species.

Therefore the relationship between the individual and the environment that has been posited by many thinkers as the cause of emotions is here reduced to the interaction between the body and the brain, which is only indirectly related to the interaction between the organism and the environment. Emotion is, indeed, about homeostatic regulation, is indeed about maintaining equilibrium, but the equilibrium is, more specifically, between external stimuli and internal representations.

Feelings, on the contrary, are perceptions. Damasio argues that feelings are views of the body's internal organs: feelings are percepts. This follows from his view of what the mind is: the mind is about the body. The neural processes that I experience as "my mind" are about the representation of my body in the brain. The mental requires the existence of a body, and not only because it has to be contained in something. Feelings express this function of the mind. This also explains why we cannot control the feelings of emotions: we can't because we can't change the state of our body, or, better, we can control emotions to the extent that we can change the state of our body that caused that emotion.

Of course, that representation of the body is always present in the brain, but it is mostly dormant. It takes a specific stimulus to trigger it and generate an emotion, which in turn will yield a feeling.

William James had already argued that feelings are a reflection of a change in the state of the body. Damasio gives it a detailed model: first an external stimulus triggers certain regions of the brain, then those regions cause an emotion, then the emotion spreads around the body and causes a change in the state of the body, and finally the "mind" perceives that change of state as a feeling.

Since feelings are percepts, they must be considered as cognitive as any other percept, as cognitive as an image or as a word.

Emotion as Memory

The more emotions are analyzed from a biological perspective, the more apparent it is that emotion is not a separate subsystem of the mind, but a pervasive feature of it. It has a specific evolutionary function and a crucial role in our daily actions.

Emotions are key to learning and behavior, because fear conditioning imprints emotional memories that are quite permanent. The relationship between emotion and memory goes beyond fear, but fear is the emotion that has been studied more extensively. As a matter of fact, fear seems to be a common ground for (at least) all vertebrates. The effects of fear on memory are powerful. John Aggleton has offered a model of how memories about fearful experiences are created in the brain by interactions among the amygdala, the thalamus and the cortex.

Emotional memory (stored in the amygdala) differs from declarative memory (which is mediated by the hippocampus and the cortex). Emotional memory is primitive, in the sense that only contains simple links between cues and responses. A noise in the middle of the night is enough to create a state of anxiety, without necessarily bringing back to mind full consciousness of what the origin of that noise can be. This actually increases the efficiency (at least the speed) of the emotional response.

Emotional and declarative memories are stored and retrieved in parallel. Adults cannot recall childhood traumas because in children the hippocampus has not yet matured to the point of forming conscious memories, but the emotional memory is there.

Emotions are the brain's interpretation of reactions to changes in the world. Emotional memories involving fear can never be erased The prefrontal cortex, amygdala and right cerebral cortex form a system for reasoning that gives rise to emotions and feelings. The prefrontal cortex and the amygdala process a visual stimulus by comparing it with previous experience and generate a response that is transmitted both to the body and to the back of the brain.

Darwinian emotions?

The amygdala has been recognized as a major center for the creation of emotions. For example, animals whose amygdala was removed showed no emotions. It turns out, though, that the neurons of the amygdala are continuously generating what appear to be emotional states, just like the heart beats all the time. This goes against our belief that emotions are due to our reaction to external stimuli. Instead we seem to be producing emotions all the time, regardless of the external stimuli.

Whenever modern Science finds itself in this situation, Darwin's specter arises: are emotions just like antibodies, neurons and thoughts? Are they produced randomly all the time and then the environment (the situation) "selects" which ones have to survive?

The Complexity of Emotions

Two mysteries remain. The first one is relative to consciousness: why do I also have to "feel" the emotion? Couldn't the brain just send a signal to the organs without bothering me? Why am I aware of it? A possibility is that being aware of an emotion means that the self can preempt the mechanic activation of a response in cases in which it would be counterproductive. Sometimes fear or hunger can lead us to actions that we may regret. If we were not aware of our emotions, we would not be able to stop the consequent actions.

The second mystery is how did we to come to build such complex feelings as, say, love. Love for a child is relatively easy to explain. But love for a woman is often a rather contorted and turbulent affair. Most of the emotions we feel during a day would be hard to be categorized as simple "fear" or "love" or "pain". They seem to be grounded on such simple, primitive emotions, but then they exhibit a degree of complexity above that. Are they "evolutionary" consequences of primitive emotions (just like a human brain is the evolutionary consequence of very primitive nervous systems), which are now part of our genetic program, or are they "social" consequences of interaction with other emotional beings: are they innate or acquired? How is a complex emotion formed from more elementary emotions?

And, again, one more "why": what is the advantage of building more and more complex emotions? Could it be that more complex emotions express a better balance of reason and instinct?

For a theory of emotions

I have an inner life, which is not a bodily life. Within this inner life (which is customary to call "mind") different types of things occur. I think. I feel emotions. I dream.

As neurophysiologists make progress on the functioning of the brain, it is beginning to appear that there is a difference between emotions and thinking. Emotions are often not desired: they occur because of external stimuli. I don't have much control over them, but they are not spontaneous: I can always relate them to an external event. Emotions have no logical construct, no flow, no time dimension. They simply happen and slowly fade away or change into other emotions: their only dimension is their intensity.

The main difference between emotions and thought is that thoughts do have a time dimension and can evolve over time. Thoughts can be controlled: I can decide if I want to think or not, and what I want to think. But they can also be spontaneous, just like emotions. Both emotions and thought result in behavior. Therefore, my behavior is driven by both emotions and thought, by both controlled and non controlled inner behavior. Thought also results in emotions, albeit of a different type (like depression or anxiety).

Cognition sort of mediates between emotions and thought. Emotions help organize the world in the mind, and that is what thought operates upon. Each emotion changes the mind and how deeply the emotion changes the mind depends on how intense the emotion is. That "change" is a change in cognition.

Thought can also generate a change in cognition, but we can fairly assume that even thought needs to generate an emotion before a meaningful, lasting change is performed on cognition. Basically, we can assume that nothing changes in our mind unless an emotion is created. The emotion is what causes the mind to reorganize itself.

If this is indeed the case, then one is faced with the fact that emotion, cognition and thought repeat themselves virtually ad infinitum. Senses cause sensations, which cause cognitive events, which cause thought, which cause higher-level emotions, which cause higher-level cognitive events, which cause thought, which cause even higher-level emotions, etc. The process gets weaker and weaker as it moves higher, and in most cases it actually never reaches the second level (in a significant way, at least). This process is a process similar to resonance that continues virtually forever, although is stops quickly being meaningful, especially if new sensations start another chain of events.

Sometimes the reaction to sensations is almost nil. There is almost no thinking.

Nonetheless, emotions play the key role of being preconditions to cognition.

The self and free will operate at the level of "thought". Somehow cognition enables not only the "linguistic" form of consciousness which is thought, but also the self-reflection and the initiative that uniquely characterize thought.

The question, from an almost evolutionary viewpoint, is whether thoughts are simply an evolution of emotions: language enabled us to control emotion and to develop something equivalent to emotion but more subtle. Or whether they are two different aspects, and they always were different.

Free will is an important variable in this equation. There is no doubt that the ability to decide what I do has to play a key role in a definition of thought. But note that free will is almost the opposite of emotions: emotions are beyond "our" control.

The machinery of "mind", or "cognition" (memory, learning, reasoning, language), is at the service of our primary inner life: thoughts and emotions (and even dreams). The machinery of "mind" is really a mediator between our primary inner life and our bodily life. I can remember an event, and then feel an emotion or think about that event. Viceversa, I may be thinking of something and recall an event. My inner life needs a physical support to be stored and retrieved. My current inner life needs a physical support to communicate with my previous inner life. The time dimension of thinking is implemented in the physical support. That physical support is the brain.

A similar relationship applies to thought and consciousness. There is one skill, capability, that brains have, and there is the feeling associated to it. By "thought" we normally mean the capability of thinking, of putting memories and words and images together. By "consciousness" we really mean (among other things) the feelings associated with thinking. Thought is therefore also a "mediator": between consciousness and the brain.

Do emotions need a brain to occur? Presumably they don't need a brain as complex as ours. I feel pain in my foot. I feel anguish in my heart. There really isn't any need for an additional piece of body. We assume that the brain is the place where emotions communicate with the "I", and that would explain why emotions also need a brain.

Sensations, feelings and emotions are confusing terms that are often applied to the same things. Some emotions are localized and some emotions are not localized. The pain in my foot is localized, but my fear of death, my career ambitions and my desire of learning are not localized. Most emotions correspond to bodily needs, but some correspond to more abstract entities that have to do with thought itself. You need to be a thinking subject to desire to learn. Career ambitions refer to a vast complex system of values that has been built with thought. Even my fear of death is really a fear of "inner" death, not of bodily death, and therefore refers again to thought.

This distinction may prove essential to an understanding of emotions. Some emotions (let's call them "bodily emotions") are localized and refer to the life of body parts. Some emotions (let's call them "inner" emotions) are not localized and refer to the inner life of thought. If thought is an evolution of emotions, then these are emotions about emotions.


Further Reading


Aggleton John: THE AMYGDALA (Wiley-Liss, 1992)
Buck Ross: THE COMMUNICATION OF EMOTION (Guilford Press, 1984)
Damasio Antonio: DESCARTES' ERROR (G.P. Putnam's Sons, 1995)
DeSousa Ronald: THE RATIONALITY OF EMOTION (MIT Press, 1987)
Ekman Paul: THE NATURE OF EMOTION (Oxford Univ Press, 1994)
James William: PRINCIPLES OF PSYCHOLOGY (1890)
Jauregui Jose: THE EMOTIONAL COMPUTER (Blackwell, 1995)
Klopf Harry: THE HEDONISTIC NEURON (Hemisphere, 1982)
Lane Ricahrd & Nadel Lynn: COGNITIVE NEUROSCIENCE OF EMOTION (Oxford Univ Press, 2000)
Lazarus Richard: EMOTION AND ADAPTATION (Oxford Univ Press, 1991)
Lazarus Richard & Lazarus Bernice: PASSION AND REASON (Oxford Univ Press, 1994)
LeDoux Joseph: THE EMOTIONAL BRAIN (Simon & Schuster, 1996)
Mandler George: MIND AND BODY (Norton, 1984)
Oatley Keith & Jenkins Jennifer: UNDERSTANDING EMOTIONS (Blackwell, 1996)

Ortony Andrew, Clore Gerald & Collins Allan: THE COGNITIVE STRUCTURE OF EMOTIONS (Cambridge Univ Press, 1988)

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