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
Aim: Determine the volume in the amygdala in a series of brains post-mortems
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
Aim: Examine neural activity in amygdala during episodes of mania.
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.
Aim: Investigate what happens in the amygdala during and after phobia treatment
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
Post-traumatic stress disorder
Temporal lobe epilepsy the brain
Inability to recognize facial expressions
Other psychiatric disorders
Causes of Disfunction
Damage by injury
Bibliography of Studies:
Chance, S. A., Esiri, M. M., & Crow, T. J. (2002). Amygdala Volume in Schizophrenia: Post-mortem Study and Review of Magnetic Resonance Imaging Findings . Abstract retrieved from bjp.rcpsych.org/cgi/reprint/180/4/ 331.pdf
Altschuler, L., M.D., Mazziotta, J., M.D., Ph.D., Firestine, A., B.A., Bartzokis, G., M.D., Mintz, J., Ph.D., & Bookheimer, S., Ph.D. (2005, June). Increased Amygdala Activation During Mania: A Functional Magnetic Resonance Imaging Study. Abstract retrieved from UCLA, American Psychiatric Association, VA Greater Los Angeles Healthcare System website: http://ajp.psychiatryonline.org/cgi/content/full/162/6/1211
Furmark, T., Ph.D., & Fredrikson, M., PhD. (2005, July). Figuring out Phobias . Abstract retrieved from American Psychological Association website: http://www.anxietyandstress.com/specificphobias.html
("Brain." Reviewed by Robert L. Knobler. Encyclopedia Americana . 2010. Grolier Online. 31 Mar. 2010 <http://ea.grolier.com/article?id=0058500-00>.