The Amygdala

By: Alinka, Harel, Vjosa

General Information; Location

General Location 1-inch-long structure Group nuclei situated

beneath the cortex Beneath the surface of

the temporal lobe on the tip of the long

hippocampus cord Few inches from the ear

Parts of Amygdala

Basolateral Amygdala

Central Amygdala

Ventral Amygdala

Dorsal Amygdala

General Information; Function• Feelings of lust,

curiosity, fear• Part in storage of

emotional memories▫ Processes & assigns

emotional "value" to received sensory input

▫ Through connection with the hypothalamus, it appears to have some mediating effect on the "fight-or-flight”

▫ Response that occurs when an individual is confronted with a dangerous situation

Study #1• Aim: Determine the volume in the

amygdala in a series of brains post-mortems

• Procedure: ▫Amygdala volume was estimated

using point-counting in both hemispheres of brains of 10 male and 8 female patients with schizophrenia

▫Had a comparison group of 9 male and 9 female post-mortems without neuropsychiatric disorder

• Results: No significant reduction of amygdala found 

Study #2

• Aim: Examine neural activity in amygdala during episodes of mania. 

• Procedure: ▫ 9 manic participants & 9 healthy comparison

subjects underwent fMRI while performing a neuropsychological paradigm

▫ Experimental Task: participants look at faces displaying affection

▫ Control task: geometric forms▫ Goal: Match them to one of two similar images

presented at same time

• Results: Manic participants had significantly increased activation in the left amygdala and reduced bilateral activation in the lateral orbit frontal cortex relative to the comparison participants.

Study #3

• Aim: Investigate what happens in the amygdala during and after phobia treatment

• Procedure: ▫ Examined brain activity of 18 people with social

phobia as they spoke in front of a group using PET scans

▫ 1/3 of the participants received 9 weeks of cognitive-behavioral therapy

▫ 1/3 received Citalopram and 1/3 received no treatment.

▫ Participants were tested again, using the same public speaking task, at 9 weeks and again after one year.

• Results: Activation in the amygdala and related cortical areas at 9 weeks could predict which people's symptoms would improve after one year

Dysfunction •Anxiety•Autism •Depression•Post-traumatic stress disorder•Phobias•Temporal lobe epilepsy the brain •Inability to recognize facial expressions•Memory•Mood•Other psychiatric disorders

Causes of Disfunction

•Damage by injury•Developmental problems•Neurotransmitter imbalance

Sources• ("Brain." Reviewed by Robert L. Knobler. Encyclopedia Americana. 2010. Grolier

Online. 31 Mar. 2010 <http://ea.grolier.com/article?id=0058500-00>.• http://www.anxietyandstress.com/specificphobias.html• http://biopsychiatry.com/amygdala.htm• http://www.sci.uidaho.edu/med532/amygdala.htm• http://www.benbest.com/science/anatmind/anatmd9.html• http://annarivermount.files.wordpress.com/2009/03/citalopram.jpg• http://www.capersonalinjurycaselawnotes.com/uploads/image/PET%20scan.jpg• http://images.learningresources.com/images/products/en_us/detail/prod0912_dt.jpg• http://www.fz-juelich.de/inm/datapool/Antomicalimaging/04.jpg• http://www.liminalmusic.org/files/amygdala1.gif• http://www.efeld.com/fmscience/images/amygdala%20circuits.gif