What is this thing called emotional experience? The neuropsychology of qualia.

This crazy thing called emotional experience.

In 1884 the psychologist and philosopher William James published a theory that an emotional stimulus produces visceral changes (heart rate, respiration, sweating) and skeletal muscle changes (running, hitting, facial expressions) and that these changes are the source of the subjective experience, or feeling, of the emotion. In James' view, the feeling of the bodily response IS the feeling of the emotion, termed emotion "qualia" by philosophers. This reverses the usual notion that we run because we are afraid, or cry because we are unhappy. In the Jamesian model, we feel afraid because we run and sad because we cry. In 1927 the physiologist W. B. Cannon published a review and critique of the Jamesian model and advanced an alternative theory. Among other things, Cannon argued that the viscera and skeletal muscles act too slowly and are insufficiently discriminating to account for all emotional experience. Cannon's view suggested that the common perception that we run because we are afraid actually is correct, and it established emotion as a critical motivator of behavior.

As an alternative to James' view, Cannon pointed out that stimuli reach the brain's six-layered neocortex via subcortical systems. If the stimuli are emotional, the subcortical systems simultaneously and independently inform both the neocortex, causing emotional experience, and the relevant peripheral bodily systems, causing bodily responses. Cannon suggested--incorrectly as it turned out--that the subcortical structure particularly important in causing emotional experience is the thalamus, and for this reason his theory is sometimes dismissed as the "thalamic theory" of emotion. As more was learned about the subcortical and three-to-five layered paleocortical structures of the brain, a new model emerged. In 1937 the neuroanatomist James Papez suggested that bodily expression of emotion involves the hypothalamus, which controls the autonomic and endocrine systems; whereas emotional experience involves the limbic system, comprising the paleocortical structures of the brain plus the amygdalae. Later, Paul D. MacLean proposed the "Triune Theory" which viewed the brain as a hierarchy, the parts of which appeared successively over the course of evolution with newer structures superimposed over older ones. The "reptilian" portion includes the oldest structures--brainstem, midbrain, and basal ganglia--the "paleomammalian" portion includes the limbic system, and the "new mammalian" portion includes the neocortex.

Research in what has come to be termed affective neuroscience is broadly consistent with MacLean's triune view. In particular, psychoactive drugs have been found to alter emotional feelings in ways largely independent of actual circumstances as appraised by the individual. These drugs have been associated with specifiable neurochemical systems, often the amygdalae and limbic system structures. However, James' view of emotional experience has proved resilient. It appeared, for example, in the 1963 social psychological model of Stanley Schachter and Jerome Singer, which viewed emotion to be a combination of physiological arousal and cognitive explanations for that arousal. The cognitive factors helped account for Cannon's objections regarding the slowness and lack of discrimination of visceral response. More recently, Antonio Damasio and colleagues explained impairment in decision-making associated with damage in the brain's frontal cortex by the inability to generate normal somatic responses to emotional events. The Somatic Marker Hypothesis stated that positive or negative incentive values associated with appraisal and decision-making are stored as somatic markers in the frontal cortex. Activation of these markers produces bodily feelings of approach or avoidance that in turn contribute to decision-making.

Others argue that brain activity is related to felt emotion directly, and that involvement in decision-making of peripheral somatic processes is unnecessary. Also, the influences of emotion upon judgment and decision-making arguably extend beyond valence or approach-avoidance reactions: specific emotions can have specific effects.

There is another source of evidence relevant to the James' hypothesis: cases of anesthesia in which bodily sensation is blocked. For example, in cases of upper spinal cord injury resulting in quadriplegia, internal bodily sensation is normally blocked. Studies of spinal cord injured patients performed since the 1980s have not found evidence of lessened emotional experience in spinal-cord injured patients.

James himself recognized the relevance to his theory of having emotional feelings when bodily sensation is blocked. At the end of his 1884 paper, he cited an 1882 case of total anesthesia published by a Professor Strümpell reporting that the patient expressed shame at soiling his bed and grief because he could no longer taste a favorite dish. Upon questioning by James, Strümpell reported that the patient also expressed and appeared to experience fear and anger. James acknowledged that if "the patient recognized explicitly the same mood or feeling known under those names in his former normal state, my theory would of course fall. It is, however, to me incredible that the patient should have an identical feeling, for the dropping out of the organic sounding-board would necessarily diminish its volume in some way" (p. 205). However, the data from spinal cord injuries appear to support Cannon's comment that the volume contributed by James' organic sounding board is faint indeed. Bodily feedback appears to be neither necessary nor sufficient for the subjective experience of emotion.

William James (1884). What is an Emotion? Mind, 9. pp. 188-205.

Portions taken from R. Buck, Human Motivation and Emotion, 2nd Edition, Wiley 1988.