Poster 47THALAMUS VOLUME AND SHAPE IN MALE ADOLESCENTS WITHEARLY-ONSET FIRST-EPISODE PSYCHOSIS

Joost Janssen1,2,3, Yasser Alemán2,3, Santiago Reig1,3, Hugo Schnack4,Mara Parellada2,3, Monserrat Graell5, Carmen Moreno2,3,Dolores Moreno2,3, J.M. Mateos-Pérez1, J.M. Udias6, Manuel Desco1,Celso Arango2,31Hospital Universitario Gregorio Marañón, Department of ExperimentalSurgery and Medicine; 2Hospital Universitario Gregorio Marañón,Department of Psychiatry; 3Centro de Investigación Biomédica en Redde Salud Mental (CIBERSAM) Madrid, Madrid, Spain; 4Rudolf MagnusInstitute of Neuroscience, Department of Psychiatry, University MedicalCenter Utrecht, Utrecht, Utrecht, Netherlands; 5Hospital UniversitarioInfantil Niño Jesús, Department of Psychiatry Madrid, Madrid, Spain;6Universidad Complutense de Madrid, Grupo de Física Nuclear, FísicaAtómica, Molecular y Nuclear Madrid, Madrid, Spain

Background: Post-mortem and in vivo research in adult patientswith first-episode psychosis indicate volume deficits in anterior,mediodorsal and posterior thalamic subnuclei. In adolescentpatients with psychosis, it is unclear if these thalamic subregionsare affected. The study was designed to compare whole andregional thalamus volume between a sample of minimally treatedmale adolescents with early-onset first-episode psychosis (EOP)and male healthy controls.Methods: Baseline Magnetic Resonance Imaging (MRI) brainscans were obtained from 49 adolescent EOP patients, and 34healthy controls. Subjects were younger than 19 years (age range12-18 years), and EOP patients had the first psychotic symptomsbefore the age of 18 years. All patients had less than six months ofpsychotic symptoms at study enrollment. All patients had a two-year clinical follow up assessment including a K-SADS-PL inter-view. At the two year follow up, 13 patients had schizophrenia, 17patients had bipolar I disorder, 16 patients had another psychoticdisorder, and 3 patients did not fulfill K-SADS-PL criteria forpsychosis. At baseline, all patients were on antipsychoticmedication, the mean daily chlorpromazine equivalent (CPE)dose of the patient sample was 401. To ensure that our MRIfindings were not dependent on scan preprocessing, two differentautomated procedures were used to assess thalamus volume(FreeSurfer and Fmrib Software Library-FIRST, both freely avail-able). Regional thalamic shape analysis using Spherical Harmo-nics (SPHARM) was used to localize regional thalamic volumedeficits.Results: Within patients, right and left thalamus volumes were notcorrelated with dose of CPE. After controlling for total brain volumeand age, EOP was associated with a significant volume deficit in theright thalamus. After a Bonferroni correction for multiple compar-isons, the shape analysis showed surface deflation in a right anteriormediodorsal subregion in EOP patients, meaning that in thisanterior mediodorsal region the surface of the patients sank insidethe surface of controls. i.e a volume deficit. Both volume and shapemeasures were not correlated with positive and negative PANSSsymptom ratings.Discussion: Thalamus volume deficits are present in minimallytreated male adolescent EOP patients. Coherent with findings inadult-onset first-episode psychosis, a specific structural abnorm-ality in the right thalamic anterior mediodorsal subregion wasobserved in male adolescent-onset EOP, indicating particularinvolvement of the individual anterior and mediodorsal subnucleiat the onset of psychosis.

doi:10.1016/j.schres.2010.02.275

Poster 48DISORDERS OF THE BASIC SELF AS A MARKER OF VULNERABILITYFOR SCHIZOPHRENIA: PRELIMINARY EMPIRICAL SUPPORT FROMNON-PSYCHOTIC HELP-SEEKING ADOLESCENTS

Danny Koren1, Noa Reznick1, Merav Adres1, Ravit Scheyer1,Alan Apter2, Tamar Steinberg2, Josef Parnas31University of Haifa, Haifa, Haifa, Israel; 2Schneider Childern's MedicalCenter, Petach Tiqvah, Tel Aviv, Israel; 3University of Copenhagen,Copenhagen, Copenhagen, Denmark

Background: A recent first person account in Schizophrenia Bulletin(Kean, 2009) suggests that schizophrenia is fundamentally a self-disturbance. The overarching goal of this presentation is to report anddiscuss preliminary empirical support for the idea that a disorder of thebasic self is indeed a core defect in schizophrenia that precedes its acuteonset. More specifically, we will: 1) briefly present our analysis of themain limits of current research on early markers of risk for schizo-phrenia, 2) explainwhywebelieve that a phenomenologically informedempirical exploration of subjective experience holds out the promise ofaddressing these limitations, and3)present a pilot studyamong87non-psychotic help seeking adolescents that tested this hypothesis.Methods: The prevalence and nature of basic self disorders wasassessed with the Examination of Anomalous Self-Experience (EASE:Parnas et al, 2005). Next, to assess the relationship betweendisturbances of the basic self and current high-risk markers, thepresence and severity of prodromal symptomswere screenedwith theProdromal Questionnaire (PQ: Loewy et al., 2005) thatwas followed bya full Structured Interview for Prodromal Symptoms (SIPS: Miller et al.,2003) for participants who scored above the cut-point for probableprodromal syndrome on the PQ. Finally, deterioration in psychosocialfunctioning was assessed with Cornblatt et al.'s (2007) Social and Rolefunctioning scales that were specifically developed to assess psycho-social functioning in the prodrome.Results: Awide range of anomalous self experiences at different levelsof severity has been reported by about two thirds of the sample.However, only less than one quarter (23%) was judged to suffer fromanomalies of self-experience at a clinically meaningful level. Thisproportion was smaller than the number of participants (32%) whomet diagnostic criteria for a prodromal syndrome. The degree ofoverlap between the two conditions was moderate (14%) but notsignificant (c2(1)=2.9, p=.09). Similarly, an exploratory factor analysiswith oblique rotation revealed that anomalies of self experience loadofa different factor thanprodromal symptoms, but that there is amodestcorrelation between the two factors. Interestingly, deterioration insocial functioning loaded more highly on the anomalous selfexperiences factor than on the prodromal symptoms one.Discussion: These preliminary findings suggest that anomalousself-experiences can enrich current early detection models byproviding a means of further “closing in” on a smaller subgroup ofindividuals truly at high risk of schizophrenia spectrum disorder.

doi:10.1016/j.schres.2010.02.276

Poster 49IMPAIRED MOTOR CONTROL IN ADOLESCENTS AT HIGH RISKFOR SCHIZOPHRENIA

Theo Manschreck1, Larry Seidman1, Stephen Faraone2,Ming Tsuang3, Brendan Maher11Harvard University, 1,2,3,5 Boston, MA, USA; 2SUNY Upstate MedicalUniversity, Syracuse, NY, USA; 3University of California, San Diego, SanDiego, CA, USA

Background: We present evidence from the Harvard AdolescentHigh Risk Study designed to determine the association between

Abstracts 203