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Archive for the ‘emotions’ Category

by Robert T. Gonzalez

The power of suggestion can be an incredible thing, and in few way is this more apparent than with the placebo effect. Now, newly published research suggests how susceptible you are to sham treatments and dummy medicine (a sugar pill, for instance) could actually be rooted in your genetics.

LiveScience’s Tia Ghose explains:

Differences in versions of the catechol-O-methyltransferase (COMT) gene, which determines levels of dopamine in the brain’s prefrontal cortex, are linked to differences in reward-seeking and pain perception. People with the high-dopamine version, or allele, of the COMT gene feel pain more acutely and seek rewards more strongly than those who have the low-dopamine copy.

[Researchers led by Kathryn Hall of Beth Israel Deaconess Medical Center] analyzed DNA from 104 patients with irritable bowel syndrome who were randomized to one of three groups: One was told they were on the waiting list for treatment, another received a placebo in the form of seemingly real, curt acupuncture, and the third group received fake acupuncture from a caring, warm practitioner who looked patients in the eye, asked about their progress, and even touched them lightly.

Patients with the high-dopamine version of the gene felt slightly better after seeing the curt, all-business health-care provider that gave placebo acupuncture. But they were six times as likely to say their symptoms improved with a caring practitioner as those with the low-dopamine gene, who didn’t improve much in any group.

In the latest issue of PLOS ONE, Hall and her colleagues note that knowing if a person is genetically predisposed to respond favorably to a sham form of treatment could prove invaluable in clinical trials designed to test the effectiveness of drugs and other therapies. After all, if everyone in your placebo group is hardwired to respond favorably to any treatment — even to a sugar pill — it could seriously skew experimental results. Conversely, if the entire placebo group is genetically predisposed to not respond to placebos, it could cast the prospective therapy in a disproportionately favorable light.

Read more about Hall’s research over at LiveScience.

[PLOS ONE via LiveScience]

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The James–Lange theory refers to a hypothesis on the origin and nature of emotions and is one of the earliest theories of emotion, developed independently by two 19th-century scholars, William James and Carl Lange.

This theory states that within human beings, there is a response to experiences in the world and that the autonomic nervous system creates physiological events such as muscular tension, a rise in heart rate, perspiration, and dryness of the mouth. Emotions, then, are feelings which come about as a result of these physiological changes, rather than being their cause. James and Lange arrived at the theory independently. Lange specifically stated that vasomotor changes are emotions. (Ex. A person rationalizes that because he/she is crying, he/she must be sad.) James elucidated his concept as:

My theory … is that the bodily changes follow directly the perception of the exciting fact, and that our feeling of the same changes as they occur is the emotion. Common sense says, we lose our fortune, are sorry and weep; we meet a bear, are frightened and run; we are insulted by a rival, are angry and strike. The hypothesis here to be defended says that this order of sequence is incorrect … and that the more rational statement is that we feel sorry because we cry, angry because we strike, afraid because we tremble … Without the bodily states following on the perception, the latter would be purely cognitive in form, pale, colorless, destitute of emotional warmth. We might then see the bear, and judge it best to run, receive the insult and deem it right to strike, but we should not actually feel afraid or angry.
This order of causality is a difficult one. The theory has been largely disfavored in modern times. Some evidence to support it, however, may come from the fact that sufferers of various psychological challenges such as panic disorders often experience psychoemotional trauma after physiological responses arise in the body, responses which individuals are conditioned to associate with a particular emotional state but which can, via therapy, be dissociated.

This theory was challenged in the 1920s by psychologists such as Walter Cannon and Philip Bard, who theorized that physiological changes are caused by emotions, collectively known as the Cannon-Bard theory of emotion.

Cannon–Bard theory

Walter Bradford Cannon (1871-1945) was a physiologist at Harvard University, who is perhaps best known for his classic treatise on homeostasis.[1] Philip Bard (1898-1977) was a doctoral student of Cannon’s, and together they developed a model of emotion called the Cannon-Bard Theory.[2] Cannon was an ardent experimenter who relied on studies of animal physiology. Through these studies, Cannon and Bard highlighted the role of the brain in generating physiological responses and feelings; a role that is important in their explanation of emotion experience and production.[3]

The Cannon-Bard Theory, also known as the thalamic theory, suggests that individuals experience emotions and physiologically react simultaneously. These actions include changes in muscular tension, perspiration, etc. This theory challenges the James-Lange theory of emotion introduced in the late 19th century, which suggests that emotion results from one’s “bodily change,” rather than the other way around.[4]

The theory sparked much controversy in cognitive circles due to its suggestion that emotion lacks a mechanism, and many theorists attempted to provide explanations of emotion that suggested a mechanism. One such theory was provided by Schachter & Singer’s two factor theory of emotion, in which they posited that emotion is the cognitive interpretation of a physiological response. For many, this remains the best formulation of emotion.

I see a man outside my window. I am afraid. I begin to perspire.

The Cannon-Bard Theory of Emotion is based on the premise that one reacts to a specific stimulus and experiences the corresponding emotion simultaneously. Therefore, if one is afraid of heights and is traveling to the top of a skyscraper, they are likely to experience the emotion of fear. Subsequently, the perception of this emotion (fear) influences the person’s reaction to the stimulus (heights). Cannon and Bard posited that one is able to react to a stimulus only after experiencing the related emotion and experience.[6]

The third theory of emotion is Schachter & Singer’s two factor theory of emotion. This theory states that cognitions are used to interpret the meaning of physiological reactions to outside events.

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