Table 1. A summary of previous studies highlighting structural neuroanatomical abnormalities in the amygdala of patients with pediatric bipolar disorder.

Study	Study groups	PBD age Mean (SD)	Controls age Mean (SD)	Amygdala abnormalities reported
Chang et al. 2005 (11)	PBD/controls	14.6 (2.8)	14.1 (2.8)	Reduced volume in PBD
Dickstein et al. 2005 (12)	PBD/controls	13.5 (2.5)	13.3 (2.3)	Reduced volume in PBD (left amygdala)
Blumberg et al. 2003 (13)	PBD/controls	15.0 (4.0)	15.3 (2.8)	Reduced volume in PBD
Chen et al. 2004 (25)	PBD/controls	16.0 (3.0)	17.0 (4.0)	Reduced volume in PBD (left amygdala)
DelBello et al. 2004 (26)	PBD/controls	16.3 (2.4)	17.2 (1.9)	Smaller amygdala in PBD

SD = standard deviation; PBD = pediatric bipolar disorder.