1 Baylor College of Medicine, 2 School of Medicine and Psychology, Sapienza University, Sant’Andrea Hospital, 3 University of Texas Medical School at Houston Background: Emotional dysregulation in pediatric bipolar disorder (pBD) can affect attentional processes, which are influenced by response preparation. However, the temporal dynamics of emotional interference on response preparation in pBD is poorly evaluated. Our aim is to explore P100 and LPP amplitudes during response preparation processes with emotional distractors in patients with pBP and healthy controls (HC). Methods: Enrolled were 7- to 17- year-old subjects with pBP (N¼13) and healthy controls (HC) (N¼12). Subjects passively viewed fearful, neutral and happy faces on a green, red or blank background. Subjects were required to perform a cognitive task cued by green and red backgrounds, whereas no action was required after viewing the blank screen. P100 was recorded between 70ms and 140ms, whereas LPP was recorded between 300 and 1000ms. Effects were explored with general linear models. Results: We found a color*group interaction (p¼0.12). Post- hoc analyses revealed that only in patients, the blank back- ground elicited greater P100 amplitude than both red (p¼0.064; Cohen’sD¼0.654) and green background (p¼0.088; Cohen’sD¼0.499), irrespective of the emotional face. We explored also a trend level significant emotion*group interac- tion (p¼0.06). Post-hoc analyses revealed that happy faces elicited greater P100 amplitude than fearful faces (p¼0.01; Cohen’sD¼0.246), irrespective of the background. As regard the P100 peak latency, both green and red backgrounds eli- cited a later peak than blank background (p¼0.029; Cohen’s D¼0.733 and p¼0.019; Cohen’sD¼0.850, respectively). Conclusions: Youth with pBP demonstrate poor early atten- tional visual processing, possibly due to an interference from emotional stimuli to the available attentional resources. Supported By: Dunn Foundation Keywords: Emotion Regulation, Neurophysiology, Pediatric Bipolar Disorder, Emotional Face Processing S55. Neural Responses to Reward in Childhood Predict Stress Reactivity in Early Adolescence Aria Vitale 1 , Pablo Vidal-Ribas 1 , Brenda Benson 1 , Nathan A. Fox 1 , Daniel S. Pine 1 , and Argyris Stringaris 1 1 National Institute of Mental Health, National Institutes of Health, University of Maryland Background: Altered responses to both reward and acute stress are a well-known risk factor for psychiatric disorders, including depression and anxiety. Whereas some studies have examined changes in neural reward processing under or after stress conditions, few studies have tested whether such re- sponses are related to stress reactivity later in life, especially in sensitive developmental periods such as early adolescence. Methods: Thirty-four participants, twenty females, performed a reward processing task during fMRI at age 10 (M¼10.5, SD¼0.4), and then a version of the Trier Social Stress Test (TSST) at age 13 (M¼13.2, SD¼0.6). Multiple linear regression analysis tested whether changes in BOLD signal during reward anticipation, and encoding of reward prediction error (RPE) during reward feedback, predicted both observer- and self- reported stress reactivity three years later. Results: During reward anticipation, lower left ventral caudate response was associated with higher self-reported stress in the TSST three years later (b¼-0.37, p¼0.037), whereas lower insula response was associated with higher observer-reported stress (b¼-0.56, p¼0.001). Stronger RPE signals encodings in the right ventral caudate and cingulate cortex were associated with higher self- (b¼0.40, p¼0.025) and observer-reported stress (b¼0.39, p¼0.025), respectively. Conclusions: Diminished ability to foresee positive out- comes as a consequence of one’s performance, highlighted by lower anticipation and higher sensitivity to such outcomes when these happen unexpectedly, might increase anticipatory anxiety when facing challenging situations. On the other hand, stronger RPE signals might also facilitate positive learning under conditions of treatment exposure to aversive situations. Supported By: NIMH Intramural Research Program Keywords: Reward, fMRI, Stress Reactivity, Trier Social Stress Test, Children and Adolescence S56. The Neural Correlates of Frustration in Youth With Disruptive Behavior Disorders James Blair 1 , Laura Thornton 1 , Harma Meffert 1 , Kathryn Adams 1 , Elizabeth Ternent 1 , Abraham Killanin 1 , Patrick Tyler 1 , Matthew Dobbertin 1 , Kayla Pope 2 , Stuart White 1 , and James Blair 1 1 Boys Town National Research Hospital, 2 Boys Town National Research Hospital, Creighton University Background: Disruptive Behavior Disorders (DBD) are a major mental and public health concern. Youth with DBDs show heightened levels of aggression, including reactive aggression (i.e., aggression in response to threat, social provocation or frustration). There have been claims that youth with DBDs have a low frustration tolerance. However, the neural correlates of frustration have not been examined in this population. Methods: Sixty youth with DBDs and 39 Typically Developing (TD) youth aged 10 to 18 years, undergoing functional MRI, completed a frustration task (Yu et al., 2014) where they worked towards a rewarded goal but could be randomly blocked from achieving this goal. Results: Relative to the TD youth, youth with DBDs exhibited stronger activation in both left ventral striatum and dorsal anterior cingulate cortex to outcome regardless of whether the participant’s goal was blocked or achieved. Moreover, within the youth with DBDs, a conduct problems severity-by- outcome interaction emerged in bilateral ventral striatum. Conduct problems severity was positively associated with greater differential responses to blocked relative to achieved goals. Conclusions: Youth with DBDs showed increased ventral striatum and dorsal anterior cingulate responses in response to frustration induction. Moreover, the degree to which partici- pants with DBDs showed a differential response to blocked Poster Abstracts S368 Biological Psychiatry May 1, 2018; 83:S129eS455 www.sobp.org/journal Biological Psychiatry