Essay About Basis Of These Early Observations And Early Part Of The Twentieth Century

The Emotional Brain, Fear, and the Amygdala
Essay title: The Emotional Brain, Fear, and the Amygdala
The Emotional Brain, Fear, and the Amygdala
SUMMARY
1. Considerable progress has beenmadeover the past 20 years in relating specific circuits
of the brain to emotional functions. Much of this work has involved studies of Pavlovian
or classical fear conditioning, a behavioral procedure that is used to couple meaningless
environmental stimuli to emotional (defense) response networks.
2. The major conclusion from studies of fear conditioning is that the amygdala plays
critical role in linking external stimuli to defense responses.
3. Before describing research on the role of the amygdala in fear conditioning, though,
it will be helpful to briefly examine the historical events that preceded modern research on
conditioned fear.
KEYWORDS: emotion; amygdala; limbio system; fear.
THE EMOTIONAL BRAIN IN PERSPECTIVE
In the early part of the twentieth century, researchers identified the hypothalamus
as a key structure in the control of the autonomic nervous system (Karplus and
Kreidl, 1927). On the basis of these early observations, and their own work (Cannon
and Britton, 1925), Cannon and Bard proposed a hypothalamic theory of emotion
that consisted of three major points: (1) the hypothalamus evaluates the emotional
relevance of environmental events; (2) the expression of emotional responses is
mediated by the discharge of impulses from the hypothalamus to the brainstem;