Hypothesis
When individuals make decisions, they must assess the incentive value of the choices available to them, using cognitive and emotional processes. When the individuals face complex and conflicting choices, they may be unable to decide using only cognitive processes, which may become overloaded.
In these cases (and others), somatic markers can help decide. Somatic markers are associations between reinforcing stimuli that induce an associated physiological affective state. Within the brain, somatic markers are thought to be processed in the ventromedial prefrontal cortex (VMPFC; a subsection of the orbitomedial PFC). These somatic marker associations can recur during decision-making and bias our cognitive processing. When we have to make complex and uncertain decisions, the somatic markers created by the relevant stimuli are summed to produce a net somatic state. This overall state directs (or biases) our decision of how to act. This influence on our decision-making process may occur covertly (unconsciously), via the brainstem and ventral striatum, or overtly (consciously), engaging higher cortical cognitive processing. Damasio proposes that somatic markers direct attention towards more advantageous options, simplifying the decision process.
The amygdala and VMPFC are essential components of this hypothesized mechanism and therefore damage to either structure will disrupt their proposed action in mediating the development and action of somatic markers. A major source of supporting evidence for this theory is provided by experiments using the Iowa gambling task.
Read more about this topic: Somatic Marker Hypothesis
Famous quotes containing the word hypothesis:
“The wheels and springs of man are all set to the hypothesis of the permanence of nature. We are not built like a ship to be tossed, but like a house to stand.”
—Ralph Waldo Emerson (1803–1882)
“The great tragedy of science—the slaying of a beautiful hypothesis by an ugly fact.”
—Thomas Henry Huxley (1825–95)
“It is a good morning exercise for a research scientist to discard a pet hypothesis every day before breakfast. It keeps him young.”
—Konrad Lorenz (1903–1989)