• PhD, University of Minnesota

I focus on the study of social development using a developmental psychopathology framework. My main research activities attempt to understand the development of subtypes of aggressive behavior in children. Specifically, my colleagues and I have been exploring the development of relational and physical aggression (and peer victimization) during early and middle childhood. Recent research examined the development of both forms (relational and physical) and functions (proactive and reactive) of aggression as well as bullying behaviors. Recent and current funded research addresses questions related to school readiness as children make the transition from preschool to kindergarten. This work includes multiple methods and informants (e.g., school-based observations, teacher and parent reports, child interviews) and includes psychophysiology and biological markers (e.g., heart rate, skin conductance, stress hormone cortisol). We are currently conducting a federally funded clinical trial to test the efficacy of a teacher-implemented with coaching social skills program (Early Childhood Friendship Project) for aggressive behavior among young children.

• Perhamus, G. R., Perry, K. J., Murray-Close, D., & Ostrov, J. M. (in press). Multi-system stress activity profiles and socioemotional functioning across the transition to kindergarten. Journal of Applied Developmental Psychology. https://doi.org/10.1016/j.appdev.2026.101931
• Azu-Narcisse, M. A., Ostrov, J. M., & Murray-Close, D. (in press). The role of parenting and cortisol in children’s early peer relationships. Child Psychiatry & Human Development. https://doi.org/10.1007/s10578-026-01967-y
• Perhamus, G. R., Ostrov, J. M., & Murray-Close, D. (2025). Parenting and peer victimization in the development of callous-unemotional behaviors: Moderation by irritability and basal cortisol. Research on Child and Adolescent Psychopathology, 53(9), 1311-1323. https://doi.org/10.1007/s10802-025-01343-9
• Perry, K. J., Ostrov, J. M., Nickerson, A. B., Godleski, S. A., Lanza, S., Schuetze, P., & Eiden, R. D. (2025). Early childhood temperament and environmental risk factors for callous unemotional traits. Clinical Psychological Science. 
• Memba, G. V., & Ostrov, J. M. (2025). Executive functioning across the transition to kindergarten: Links with social and academic outcomes in early childhood. Social Development, 34, e12788. https://doi.org/10.1111/sode.12788
• Perhamus, G. R., & Ostrov, J. M. (2025). Peer socialization processes in the development of callous-unemotional traits. Development and Psychopathology, 37,4, 2217-2234. https://doi.org/10.17/S0954579424001846
• Perry, K. J., Perhamus, G., Memba, G., Ostrov, J. M., & Murray-Close, D. (2024). A social-ecological model of preschoolers’ aggressive behavior: An exploratory analysis.School Psychology, 39(1), 95-105. https://doi.org/10.1037/dpq0000565
• Perhamus, G., Ostrov, J. M., & Murray-Close, D. (2024). Aggression and irritability in middle childhood: Between and within-person associations. Journal of Clinical Child and Adolescent Psychology, 53(2), 184-198. https://doi.org/10.1080/15374416.2023.2272941.
• Perry, K. J., Perhamus, G. R., Lent, M. C., Murray-Close, D., & Ostrov, J. M. (2023). The COVID-19 pandemic and assessments of preschoolers’ executive functions.Psychological Assessment, 35(11), 986-999. https://doi.org/10.1037/pas0001250.
• Perry, K. J., & Ostrov, J. M. (2023). Trajectories of physical and relational aggression across early childhood: Relations with peer risk factors. Aggressive Behavior, 49(4), 321-332. https://doi.org/10.1002/ab.22075
• Ostrov, J. M., Murray-Close, D., Perry, K. J., Blakely-McClure, S. J., Perhamus, G., Mutignani, L., Kesselring, S., Memba, G., & Probst, S. (2023). The development of forms and functions of aggression during early childhood: A temperament-based approach. Development and Psychopathology, 35(2),941-957. https://doi.org/10.1017/S0954579422000177
• Ostrov, J. M., Perry, K. J., Eiden, R., Nickerson, A., Schuetze, P., Godleski, S. A., & Shisler, S. (2022). Development of bullying and victimization: An examination of risk and protective factors in a high-risk sample. Journal of Interpersonal Violence, 37(9-10), 5958-5984. http://doi.org/10.1177/08862605211067026
• Perry, K. J., Ostrov, J. M., & Murray-Close, D. (2022). The role of autonomic system coordination in relations between peer factors and aggressive behavior in early childhood.Research on Child and Adolescent Psychopathology, 51, 693-708. https://doi.org/10.1007/s10802-022-01013-0
• Memba, G. V., & Ostrov, J. M. (2022). Role of peer victimization in predicting aggression and internalizing problems in early childhood: The moderating effect of emotion regulation and gender. Early Education & Development, 34(1), 53-70. https://doi.org/10.1080/10409289.2021.1997497
• Perhamus, G. R., Perry, K. J., Murray-Close, D., & Ostrov, J. M. (2022). Stress reactivity and social cognition in pure and co-occurring early childhood relational bullying and victimization. Development and Psychopathology, 34(4), 1300-1312. https://doi.org/10.1017/S0954579421000298

• SUNY Chancellor’s Award for Excellence in Scholarship and Creative Activities
• Distinguished Alumni Award, College of Education & Human Development, University of Minnesota
• Fellow, Association for Psychological Science
• Fellow, American Psychological Association and Division 53 (Society for Clinical Child and Adolescent Psychology)