how do you feel?. sometimes you feel in love… …..her dress, on that day, was of the most noble...

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How do you feel? How do you feel?

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How do you feel?How do you feel?

How do you feel?How do you feel?

Sometimes you feel in love…

…..Her dress, on that day, was of the most noble color……..At that moment, I say most truly that the spirit of life, which hath its dwelling in the secretest chamber of the heart, began to tremble so violently that the least pulses of my body shook therewith…At that moment the natural spirit, which dwelleth where our nourishment is administered, began to weep, and in weeping said these words: "Alas! How often shall I be disturbed from this time forth……

From La Vita Nova (The New Life) by Dante Alighieri (1265-1321)

Translation by Dante Gabriele Rossetti (1828-1882)

The Limbic SystemThe Limbic SystemChapter 8Chapter 8

A limbus is a margin or border A limbus is a margin or border

and the limbic system is a and the limbic system is a

border zone where psychiatry border zone where psychiatry

meets neurologymeets neurology

Limbic System

Correlation Between Neuronal Correlation Between Neuronal Activity and EEG Alpha PowerActivity and EEG Alpha Power

• Mid brain• Hypothalamus• Amygdala• Limbic Cortex• Emotional State

Correlates with alpha rhythm in the limbic system

Limbic Regions that Register Emotion

R.J. Dolan, Science, 8 Nov, 2002

Brain Regions Implicated in the Emotional Experience

Inputs to the Amygdala

What Does the Amygdala Do With the What Does the Amygdala Do With the Information From These Brain Information From These Brain

Regions?Regions?

• Maintains vigilance that is evoked by associative ambiguity or unfamiliar stimuli

• Vigilance increases information gathering and processing

• Judges causal relationships between biologically relevant stimuli

• Most often, it generates a fear response

Vigilance and emotion are Vigilance and emotion are

not so much entities that not so much entities that

reside within the amygdala reside within the amygdala

as they are processes set in as they are processes set in

motion by amygdala motion by amygdala

activation. activation.

Inputs & Outputs

Pulvinar

“I feel fear!”

Snakes or thieves…it doesn’t make any difference

Outputs: Amyloid function also influences processing within the cortex

Stimuli that Activate Stimuli that Activate the Amygdala in Humansthe Amygdala in Humans

• Aversive films, pictures, odors & tastes

• Fearful or happy facial expressions

• Masked fearful facial expressions

• Visual cues that predict electric shock

• Neutral faces that predict aversive noise

• Sad and happy faces

Amygdala Activation in Social Phobics: Amygdala Activation in Social Phobics: fMRI StudyfMRI Study

• Strong odor equally activates amygdala in controls & phobics

• Neutral faces produce enhanced amygdala activation in social phobics

• Amygdala provides emotional coloring

Individuals with social phobias demonstrated exaggerated amygdala responses to neutral facial expressions but they reported that these expressions did not make them "feel" more afraid!

Infants with an inhibited temperament tend to develop into children

who avoid people, objects, and situations that are novel or unfamiliar, whereas uninhibited children spontaneously approach novel persons, objects, and situations. Adults who had been categorized in the second year of life as inhibited, compared with those previously categorized as uninhibited, show greater functional MRI signal response within the amygdala to novel versus familiar faces.

Schwartz et al., Science, June 20, 2003.

Copyright ©2006 Society for Neuroscience

Williams, L. M. et al. J. Neurosci. 2006;26:6422-6430

Figure 1. Summary of the design of the behavioral facial emotion perception task used with identical stimuli and parameters in functional MRI and ERP testing sessions

Copyright ©2006 Society for Neuroscience

Williams, L. M. et al. J. Neurosci. 2006;26:6422-6430

changes in subcortical amygdala and basal ganglia activity over age in response to happiness and fear relative to neutral faces

Copyright ©2006 Society for Neuroscience

Williams, L. M. et al. J. Neurosci. 2006;26:6422-6430

Scatter plot with regression line depicting the significant decline over age (in years) in level of neuroticism

Males show greater activation of the amygdala in response to sexually explicit images than do females.

Hamann et al., Nature Neurosci. March, 2004

Amygdala sends Inputs to the anterior cingulate gyrus

Loss of inhibition?

rCBF as amount of chocolate increases from a little to too much

CNS AsymmetryCNS Asymmetry

• Studies involving brain damaged patients and functional imaging techniques have both revealed that, in general, the right hemisphere tends to play a greater role in emotional behaviors

Patients with bilateral amygdala damage completely lose their ability to perceive emotions related to fear; some lose their ability to perceive other emotions; and some suffer from no apparent dysfunction at all!

STENDHAL SYNDROMESTENDHAL SYNDROME• Stendhal syndrome or Stendhal's syndrome is a

psychosomatic illness that causes rapid heartbeat, dizziness, confusion and even hallucinations when an individual is exposed to art.

• It is named after the famous 19th century French author Stendhal (pseudonym of Marie-Henri Beyle), who described his experience with the phenomenon during his 1817 visit to Florence, Italy.

• Although there are many descriptions of people becoming dizzy and fainting while taking in Florentine art, especially at the Uffizi, dating from the early 19th century on, the syndrome was only named in 1979, when it was described by Italian psychiatrist Graziella Magherini, who observed and described more than 100 similar cases among tourists and visitors in Florence..