Copyri ght @ 2008 Ame ri can Academy of Chil d and Adol escent Psychi a try . Unaut hori zed r eproducti on of t hi s a rti cl e i s prohi bit ed . Neuroanatomical Correlates of Temperament in Early Adolescents SARAH WHITTLE, PH.D., MURAT YU ¨ CEL, PH.D., M.A.P.S., ALEX FORNITO, PH.D., ANNA BARRETT, B.A.(HONS.), STEPHEN J. WOOD, PH.D., DAN I. LUBMAN, PH.D., JULIAN SIMMONS, B.SC., CHRISTOS PANTELIS, M.D., AND NICHOLAS B. ALLEN, PH.D. ABSTRACT Ob j ec ti ve: Temper ament r e f ers t o enduri ng behavi or a l char act eri sti cs t ha t underpi n i ndi vi dua l di ff er ences i n human behavi or, i ncl udi ng ri sk f or psychopa t hol ogy. Research a tt empt i ng t o i nvest i ga t e t he neurobi ol ogi ca l basi soft emper ament r epr esent s an i mport ant st ep t owarde l uci da t i ng t he bi ol ogi ca l mechani sms underl yi ng t hese i ndi vi dua l di ff er ences. In t he pr esent st udy, we exami ned t he r e l a t i on be t ween f our cor e t emper ament di mensi ons and ana t omi ca ll y de f i ned r egi ons of t he li mbi c and pr e front a l cort i ces. Me t hod: We used a cross-sect i ona l desi gn t o exami ne a l arge sampl e ( N = 153; mean age 12. 6 years, SD 0. 4, r ange 11. 4Y13. 7) of hea l t hy earl y adol escent s who wer e se l ect ed from a l arger sampl e t o maxi mi ze vari a t i on i n t emper ament. The ma i n out come measur es wer e psychome tri c measur es oft emper ament (f our f act ors: e ff ortf ul control , nega t i ve a ff ect i vi t y, surgency, and a ff ili a t i veness) based on t he Earl y Adol escent Temper ament Quest i onna ir e- Revi sed, and vol ume tri c measures of apri ori br a i n r egi ons of i nt er est ( ant eri or ci ngul a t e cort ex [ ACC ], orbi t ofront a l cort ex, amygda l a , and hi ppocampus). Resu lt s: We f ound r egi ona l br a i n vol umes t o accountf or sma ll but si gni f i cant amount soft he vari ance i n se l f-r eport ed t emper ament scor es. Speci f i ca ll y, hi gher e ff ortf ul control was associ a t ed wi t h l arger vol ume oft he l e ft orbi t ofront a l cort ex and hi ppocampus. Hi gher nega t i ve a ff ect i vi t y was associ a t ed wi t h sma ll er vol ume oft he l e ft dorsa l par a li mbi c r e l a t i ve t o li mbi c port i on oft he ACC . Hi gher a ff ili a t i veness was associ a t ed wi t h l arger vol ume oft he ri ght rostr a l/ventr a l li mbi c port i on oft he ACC . A ff ili a t i veness and surgency a l so showed a number off ema l e-speci f i c associ a t i ons, pri maril y i nvol vi ng t he rostr a l/ventr a l ACC . Conc l us i ons: Ourr esul t sprovi de supportf or a neuroana t omi ca l basi s f or i ndi v i dua l di ff er ences i n t empe r ament and have i mpli ca t i ons f or unde rs t andi ng t he neurobi ol ogi ca l mechani sms underl yi ng t he deve l opment of a number of psychi a tri cdi sorders. J. Am. Acad. Chil d Adol esc. Psychi a try, 2008; 47(6): 000Y000. Key Words: br a i n vol ume , persona li t y, magne t i c r esonance i magi ng, ant eri or ci ngul a t e cort ex, ri sk f act or. Temperament refers to endogenous basic tendencies of thoughts, emotions, andbehaviors. Core tempera- ment dimensions are observable in infancy, remain relatively stable across the life span, 1 and have been shown to conferrisk for behavioral and mental health problems,particularly during adolescence, 2 when the onset of such problems is particularly pronounced. 3 Many of the neuroanatomical changes associated with adolescent and adult mental illnesses areassumed to exist before illness onset and hence likely to beasso- ciated with putative risk factors 4 ; however, little work has been conducted to directly testthis hypothesis. Thus, investigating the underlying neuroanatomy of core temperament dimensions in early adolescence represents an important step towardbetter under- standing the neural mechanisms influencing many aspects of normal and abnormal adolescent and adult behavior. Accepted January 22, 2008. Drs. Whittle, Yu ¨cel, Lubman, and Allen and Mr. Simmons are with ORYGEN Research Centre; Drs. Fornito, Wood, and Pantelis are with the Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne; and Ms. Barrett is with the Department of Psychology, University of Melbourne. This research wassupported by ORYGEN Research Centre and the Colonial Foundation. Neuroimaging analysis was facilitated by the Neuropsychiatry Imaging Laboratory, MNC, managed by Bridget Soulsby. The authors thank the Brain Research Institute for support in acquiring the neuroimaging data. Correspondence to Dr. Nicholas B. Allen, ORYGEN Research Centre, Locked Bag 10, Parkville, Victoria 3052, Australia; e-mail: nba@unimelb.edu.au. 0890-8567/08/4706-0000 2008 by the American Academy of Child and Adolescent Psychiatry. DOI: 10.1097/CHI.0b013e31816bffca WWW.JAACAP.COM 1 J . AM. ACAD. CHI L D ADOL E S C. P S YCHI ATRY, 47 : 6, J UNE 2008