It seems that people can be wrong about or unaware of many things, but at least they can be sure about their own emotions. Yet, psychologists challenge even that certainty and point out that one’s emotional life can be a mystery, even to oneself. The idea of nonconscious emotion proposes in its strongest form that people can be in an emotional state (as demonstrated by its impact on behavior, physiology, and cognition) without having any conscious awareness of being in that state.
Evidence for Nonconscious Emotion
One source of speculation about the relation between emotion and awareness are the works of Sigmund Freud. Freud clearly believed that people can be wrong about the cause of their emotion (as when a person’s anger at his or her boss comes from the similarity of the boss to the person’s father) or the exact nature of their emotions (as when a person confuses love with hate). There is little empirical support for Freud’s most dramatic speculations. However, some evidence indicates that people can be mistaken about some aspects of their emotional states. For example, one study found that in phobic individuals, negative mood can be elicited by presenting them with fear-relevant snakes and spiders. Another study found that positive mood can be elevated by repeated subliminal presentation of simple geometric figures. Many studies demonstrated that arousal resulting from one source (e.g., crossing a bridge) can be mistaken as deriving from another source (e.g., romantic attraction).
Note, however, that in these studies, people were aware of their emotions (though not of the causes). Could an emotion itself be nonconscious? Among psychologists, the issue is somewhat controversial. Some researchers think that the presence of a conscious feeling (the phenomenal component of emotion) is necessary to call a state an emotion. Other researchers think that conscious feeling is only one aspect of emotion, and the presence of emotion can be detected in behavioral and physiological changes. The latter possibility is supported by several lines of evidence.
First, from the standpoint of evolution and neuroscience, at least some forms of emotional reaction should exist independently of subjective correlates. Evolutionarily speaking, the ability to have conscious feelings is a late achievement compared with the ability to have behavioral affective reactions to emotional stimuli. Basic affective reactions are widely shared by animals, including reptiles and fish, and at least in some species may not involve conscious awareness comparable with that in humans. After all, the original function of emotion was to allow the organism to react appropriately to positive or negative events, and conscious feelings might not always have been required.
The neurocircuitry needed for basic affective responses, such as a positive reaction to a pleasant sensation or a disliking reaction to a threatening stimulus, is largely contained in emotional brain structures that lie below the cortex, such as the nucleus accumbens, amygdala, hypothalamus, and even lower brain stem. These subcortical structures evolved early and may carry out limited operations that are essentially preconscious, compared with the elaborate human cortex at the top of the brain, which is more involved in conscious emotional feelings. Yet even limited sub-cortical structures on their own are capable of some basic affective reactions. A dramatic demonstration of this point comes from affective neuroscience studies with anencephalic human infants. The brain of such infants is congenitally malformed, possessing only a brain stem, and lacking nearly all structures at the top or front of the brain, including the entire cortex. Yet sweet tastes of sugar still elicit positive facial expressions resembling liking from anencephalic infants, whereas bitter tastes elicit negative facial expressions resembling disgust.
Even in normal brains, the most effective “brain tweaks” so far discovered for enhancing basic related affective reactions all involve deep brain structures below the cortex. Thus, animal studies have shown that liking for sweetness increases after a drug that activates opioid receptors is injected into the nucleus accumbens (a reward-related structure at the base of the front of the brain). Liking reactions to sugar can even be enhanced by injecting a drug that activates other receptors into the brain stem, which is perhaps the most basic component of the brain. Such examples reflect the persisting importance of early-evolved neurocircuitry in generating behavioral emotional reactions in modern mammalian brains. In short, evidence from affective neuroscience suggests that basic affective reactions are mediated largely by brain structures deep below the cortex, raising the possibility that these reactions might not be accessible to conscious awareness.
However, neuroscientific evidence from animals and brain-damaged patients by itself is only suggestive about the idea of nonconscious emotion. Fortunately, there are some demonstrations of nonconscious emotion in typical individuals. One study explored non-conscious emotion in a paradigm where participants rated visible Chinese ideographs preceded by subliminal happy or angry faces. Though the subliminal faces influenced the ratings of ideographs, participants interviewed after the experiment denied experiencing any changes in their conscious feelings. Furthermore, participants’ judgments were still influenced by subliminal faces even when they were asked not to base their judgments of ideographs on their emotional feelings. Even better evidence for nonconscious emotion comes from a study showing that participants are unable to report a conscious feeling at the same time a consequential behavior reveals the presence of an affective reaction. Specifically, in this study participants were subliminally presented with a series of happy, neutral, or angry emotional facial expressions. Immediately after the subliminal affect induction, some participants first rated their conscious feelings (mood and arousal) and then poured themselves and consumed a novel fruit drink. Other participants first poured and consumed a drink and then rated their conscious feelings. The results showed that, regardless of the task order, the ratings of conscious feelings were unaffected by subliminal faces. Yet, participants’ consumption behavior and drink ratings were influenced by subliminal affective stimuli, especially when participants were thirsty. Specifically, thirsty participants poured more drink from the pitcher and drank more from their cups after happy, rather than after angry, faces. In short, these results suggest a possibility of nonconscious emotion in the strong sense—a reaction powerful enough to alter behavior, but of which people are simply not aware, even when attending to their feelings.
Nonconscious Emotion Implications
Thus, it seems that there are situations when a person can have an emotional reaction without any awareness of that reaction. This phenomenon has several important implications. For example, nonconscious emotions are, almost by definition, hard to control, thus raising the possibility of insidious influence by stimuli strong enough to change behavior without influencing conscious feelings. Clinically, the idea of unconscious emotion is relevant to certain kinds of psychiatric disorder, such as alexithymia, characterized by inability to access or describe one’s own feelings. The possibility that emotional behavior may occur without consciousness also raises some troubling questions whether, for example, facial or bodily emotional expressions (including that of pain) of brain-damaged patients reflect an activity of nonconscious emotional programs or some minimal consciousness.
The existence of nonconscious emotional reactions does not mean that conscious feelings are epiphenomenal—which means an interesting but unnecessary “icing on emotional cake” that plays little role in controlling behavior. Clearly, conscious feelings play an important function in what people do and deserve a central place in emotion research and clinical practice. However, the research suggests that many aspects of what is called emotion may be separable from conscious feeling, and that researchers and practitioners of emotion science should not limit themselves to self-reports of subjective experiences when assessing the presence of emotion.
Several critical questions need to be addressed by future research. First, nonconscious states might be primarily differentiated only on a positive-negative valence, rather than on more qualitative aspects associated with specific emotions (fear, anger, disgust, etc.). Some evidence indicates that subcortical circuitry is capable of qualitative differentiation, and studies could test whether different emotional behaviors could be elicited without accompanying conscious feelings. Second, the human studies discussed here relied on simple and highly learned stimuli, such as subliminal facial expressions. Future research should address whether complex, culturally coded stimuli can also elicit valenced behavioral changes without accompanying feelings. Finally, future work should examine what exact psychological and neural mechanisms determine whether an emotional reaction remains nonconscious or is accompanied by conscious feelings. The scientific research on nonconscious emotion has just began, and the near future is certain to bring many exciting findings.
- Damasio, A. R. (1999). The feeling of what happens: Body and emotion in the making of consciousness. New York: Harcourt Brace.
- Ohman, A., Flykt, A., & Lundqvist, D. (2000). Unconscious emotion: Evolutionary perspectives, psychophysiological data and neuropsychological mechanisms. In R. D. Lane, L. Nadel, & G. Ahern (Eds.), Cognitive neuroscience of emotion (pp. 296-327). New York: Oxford University Press.
- Winkielman, P., & Berridge, K. C. (2004). Unconscious emotion. Current Directions in Psychological Science, 13, 120-123.