About

Karen Wynn is Professor Emeritus of Psychology at Yale University, with a Ph.D. from the Massachusetts Institute of Technology obtained in 1990. Her scientific career has focused on studying babies to understand the human mind before it is influenced by language, culture, education, and extensive experience. Wynn's research explores how infants perceive and understand the world, including the development of morality, prejudice, and numerical cognition. She has investigated whether young babies can distinguish between good and bad individuals, whether they show preferences for those who share their tastes and opinions, and whether they possess an innate understanding of numbers, addition, and subtraction. Her findings demonstrate that even very young infants have complex notions of morality, social preferences, and numerical concepts, indicating that humans have a built-in core of numerical understanding and moral sense. Wynn's work has been recognized with awards from the National Academy of Sciences and the American Psychological Association, and her research has been funded by major agencies such as the NSF, NIMH, NICHD, and the John Templeton Foundation. Her research has been featured in numerous television documentaries and media outlets. Wynn has trained many students in scientific methods for studying early cognition, with her trainees now active researchers worldwide. She has held faculty positions at the University of Arizona and has been a visiting professor at various international institutions, including University College London, Korea University, and Tsinghua University. Currently, she is spending 2020 as the J Y Pillay Visiting Professor at Yale-NUS, engaging in teaching, writing, and art.

Research topics

• Internal medicine
• Pediatrics
• Medicine
• Physical therapy
• Radiology
• Anesthesia
• Psychiatry

Selected publications

• NICHD Magnetic Resonance Brain Imaging Score in Term Infants With Hypoxic-Ischemic Encephalopathy

  JAMA Pediatrics · 2025-02-17 · 1 citations

  articleOpen access

  Importance: The neonatal brain injury score on magnetic resonance imaging following moderate or severe hypoxic-ischemic encephalopathy developed by the National Institute of Child Health and Human Development Neonatal Research Network has been revised to separate watershed and basal ganglia or thalamic injury and their associated outcomes. Objective: To evaluate the association of the injury score with outcomes of death or moderate or severe disability among all infants, and with neurodevelopment among survivors in a trial of deeper and longer cooling. Design, Setting, and Participants: In this secondary analysis of a multicenter randomized clinical trial, brain imaging was obtained from infants between October 2010 and November 2013. Infants were followed up to 18 months of age, with follow-up completed in January 2016. Data analysis was performed from August 2021 to September 2024. Interventions: Infants were assigned to 4 hypothermia groups based on depth and duration of cooling, stratified by center and level of encephalopathy in a 2 × 2 factorial design to cooling at 33.5 °C or 32.0 °C and to 72 or 120 hours. A 10-level brain injury score was examined. Main Outcomes and Measures: The primary outcome was death or moderate or severe disability measured by the Bayley Scales of Infant and Toddler Development III, the Gross Motor Function Classification System level, vision, and hearing. Results: This study included 298 infants who had magnetic resonance imaging (MRI) and primary outcome data among 364 infants of the initial cohort (mean [SD] age at MRI, 9.18 [4.49] days). Death or moderate or severe disability occurred in 72 of 298 infants (24%), and disability occurred in 52 of 278 surviving infants (19%). Death or disability occurred in 12 of 28 infants (43%) with any or predominant watershed injury and in 17 of 46 (37%) of those with any or predominant basal ganglia or thalamic injury. Among the 32 infants with hemispheric devastation, 30 (94%) had death or disability, and 17 (89%) survived with moderate or severe disability. Injury scores of increasing severity were associated with death or disability among all infants (odds ratio, 13.66 [95% CI, 7.47-24.95]; area under the curve, 0.84 [95% CI, 0.78-0.90]) and with disability among surviving infants (odds ratio, 10.52 [95% CI, 5.46-20.28]; area under the curve, 0.80 [95% CI, 0.73-0.88]). There were no differences in the injury score between infants undergoing usual care cooling and those cooled to a greater depth or longer duration. Conclusions: Among infants with hypoxic-ischemic encephalopathy, outcomes were similar between infants with watershed and basal ganglia injury. Higher imaging scores were associated with risk of death or disability among all infants and with neurodevelopmental disability among surviving infants. Trial Registration: ClinicalTrials.gov Identifier: NCT01192776.

  PublisherOA PDFDOI

• Hydrocortisone in Preterm Infants and School-Age Functional Outcomes

  JAMA Pediatrics · 2025-12-08

  articleOpen access

  Importance: Bronchopulmonary dysplasia (BPD) is the most common in-hospital morbidity of prematurity, associated with significant long-term medical and neurodevelopmental sequelae and health resource utilization. The Neonatal Research Network (NRN) Hydrocortisone for BPD Trial evaluated the efficacy and safety of hydrocortisone to prevent BPD in high-risk very preterm infants; the impact of hydrocortisone on school-age outcomes in this trial cohort is previously unreported. Objective: To evaluate the impact of neonatal hydrocortisone treatment on early school-age functional motor, cognitive, academic, and pulmonary outcomes among children who participated in the Hydrocortisone for BPD Trial. Design, Setting, and Participants: This prospective long-term cohort study is a follow-up of a randomized clinical trial, the Hydrocortisone for BPD Trial, conducted at 19 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development NRN. Participants, enrolled from August 2011 to February 2018, included intubated infants who had been born before 30 weeks' gestational age and had been mechanically ventilated for at least 7 days by postnatal day 14 to 28. They were eligible for a single, in-person, early school-age visit between corrected age 5 years 0 months and 7 years 11 months, conducted from September 2017 to July 2024. Data analysis was performed from July 2024 to September 2025. Intervention: Participants were randomized to a 10-day tapering course of hydrocortisone or placebo beginning at 14 to 28 postnatal days. Main Outcomes and Measures: Early school-age study visits were performed by certified, masked assessors. The primary outcome of functional impairment was defined as any of the following: cognitive delay, motor delay, academic delay, or poor functional exercise capacity. Results: The primary outcome was available for 545 of 674 eligible children (80.9%), including 272 children in the hydrocortisone group (152 [55.9%] female; mean [SD] gestational age, 24.9 [1.5] weeks; mean [SD] age at visit, 5.3 [0.6] years) and 273 in the placebo group (108 [39.6%] female; mean [SD] gestational age, 24.8 [1.5] weeks; mean [SD] age at visit, 5.4 [0.6] years). There was no difference in the rate of functional impairment between the hydrocortisone group (194 of 272 children [71.3%]) and the placebo group (200 of 273 children [73.3%]) (adjusted relative risk, 0.99; 95% CI, 0.89-1.10), nor were there differences in the rates of the individual components. Motor delay was the most common impairment (308 of 510 children [60.4%]), followed by poor functional exercise capacity (175 of 484 children [36.2%]). Conclusions and Relevance: In this study, neonatal hydrocortisone treatment of preterm infants with high risk for BPD did not impact functional impairment or its components; nearly three-quarters of the children demonstrated functional impairment at school age. Trial Registration: ClinicalTrials.gov Identifier: NCT01353313.

  PublisherOA PDFDOI

• Assessment of Corticosteroid Therapy and Death or Disability According to Pretreatment Risk of Death or Bronchopulmonary Dysplasia in Extremely Preterm Infants

  JAMA Network Open · 2023 · 36 citations

  • Medicine
  • Pediatrics
  • Internal medicine

  Importance: Meta-analyses suggest that corticosteroids may be associated with increased survival without cerebral palsy in infants at high risk of bronchopulmonary dysplasia (BPD) but are associated with adverse neurologic outcomes in low-risk infants. Whether this association exists in contemporary practice is uncertain because most randomized clinical trials administered corticosteroids earlier and at higher doses than currently recommended. Objective: To evaluate whether the pretreatment risk of death or grade 2 or 3 BPD at 36 weeks' postmenstrual age modified the association between postnatal corticosteroid therapy and death or disability at 2 years' corrected age in extremely preterm infants. Design, Setting, and Participants: This cohort study analyzed data on 482 matched pairs of infants from 45 participating US hospitals in the National Institute of Child Health and Human Development Neonatal Research Network Generic Database (GDB). Infants were included in the cohort if they were born at less than 27 weeks' gestation between April 1, 2011, and March 31, 2017; survived the first 7 postnatal days; and had 2-year death or developmental follow-up data collected between January 2013 and December 2019. Corticosteroid-treated infants were propensity score matched with untreated controls. Data were analyzed from September 1, 2019, to November 30, 2022. Exposure: Systemic corticosteroid therapy to prevent BPD that was initiated between day 8 and day 42 after birth. Main Outcomes and Measures: The primary outcome was death or moderate to severe neurodevelopmental impairment at 2 years' corrected age. The secondary outcome was death or moderate to severe cerebral palsy at 2 years' corrected age. Results: A total of 482 matched pairs of infants (mean [SD] gestational age, 24.1 [1.1] weeks]; 270 males [56.0%]) were included from 656 corticosteroid-treated infants and 2796 potential controls. Most treated infants (363 [75.3%]) received dexamethasone. The risk of death or disability associated with corticosteroid therapy was inversely associated with the estimated pretreatment probability of death or grade 2 or 3 BPD. The risk difference for death or neurodevelopmental impairment associated with corticosteroids decreased by 2.7% (95% CI, 1.9%-3.5%) for each 10% increase in the pretreatment risk of death or grade 2 or 3 BPD. This risk transitioned from estimated net harm to benefit when the pretreatment risk of death or grade 2 or 3 BPD exceeded 53% (95% CI, 44%-61%). For death or cerebral palsy, the risk difference decreased by 3.6% (95% CI, 2.9%-4.4%) for each 10% increase in the risk of death or grade 2 or 3 BPD and transitioned from estimated net harm to benefit at a pretreatment risk of 40% (95% CI, 33%-46%). Conclusions and Relevance: Results of this study suggested that corticosteroids were associated with a reduced risk of death or disability in infants at moderate to high pretreatment risk of death or grade 2 or 3 BPD but with possible harm in infants at lower risk.

  PublisherOA PDFDOI

• Ingroup Positivity and Outgroup Negativity Jointly Motivate Toddlers’ Social Behavior

  The Journal of Genetic Psychology · 2023-01-17 · 1 citations

  articleSenior author

  Intergroup bias has been a pervasive phenomenon throughout human history, but its psychological underpinnings are still the subject of debate. The present work tests whether intergroup attitudes and behaviors are motivated by ingroup positivity, outgroup negativity, or both, across the first few years of life. In two studies (total N = 128), children were introduced to an ingroup doll and an outgroup doll, and interacted with each one independently in a resource allocation task. Toddlers showed both ingroup positivity and outgroup negativity (Study 1). Preschoolers shifted from this pattern, showing positivity and avoiding negativity toward both ingroup and outgroup members (Study 2). Together, these studies suggest that outgroup negativity plays a stronger role in motivating early intergroup bias than previously thought.

  PublisherDOI

• Numerical competence in infants

  Psychology Press eBooks · 2021-12-20 · 15 citations

  book-chapter1st authorCorresponding

  The abstract body of mathematical knowledge that has been developed over the last several thousand years is one of the most impressive of human achievements. What makes the human mind capable of grasping number? Philosophers and psychologists have long speculated about the origins of numerical knowledge and concepts. The empiricist account of how we possess such knowledge is that we acquire even the simplest understanding of numerical relationships from our observations of the world. The alternative is a nativist account in which some understanding of number is inherent in the structure of the mind.

  PublisherDOI

• Adults’ pedagogical messages engender children's preference for self‐resembling others

  Developmental Science · 2021-12-03 · 5 citations

  articleOpen accessSenior author

  These studies investigate the influence of adults' explicit attention to commonalities of appearance on children's preference for individuals resembling themselves. Three findings emerged: (1) An adult's identification of two dolls' respective similarity to and difference from the child led 3-year-olds to prefer the similar doll (study 1, n = 32). (2) When the adult did not comment on similarity, children age 6 years but not younger preferred physically similar individuals (study 2, n = 68), suggesting that a spontaneous preference for physically similar others does not emerge before school age. (3) Four- but not 3-year-olds generalized an adult's pedagogical cues about similarity, leading them to prefer a self-resembling doll in a new context (study 3, n = 80). These findings collectively suggest that the preference for individuals resembling ourselves develops through a process of internalizing adults' attention to, and messages about, similarities of appearance.

  PublisherOA PDFDOI

• Association Between Increased Seizures During Rewarming After Hypothermia for Neonatal Hypoxic Ischemic Encephalopathy and Abnormal Neurodevelopmental Outcomes at 2-Year Follow-up

  JAMA Neurology · 2021 · 43 citations

  • Medicine
  • Anesthesia
  • Pediatrics

  Importance: Compared with normothermia, hypothermia has been shown to reduce death or disability in neonatal hypoxic ischemic encephalopathy but data on seizures during rewarming and associated outcomes are scarce. Objective: To determine whether electrographic seizures are more likely to occur during rewarming compared with the preceding period and whether they are associated with abnormal outcomes in asphyxiated neonates receiving hypothermia therapy. Design, Setting, and Participants: This prespecified nested cohort study of infants enrolled in the Optimizing Cooling (OC) multicenter Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Neonatal Research Network trial from December 2011 to December 2013 with 2 years' follow-up randomized infants to either 72 hours of cooling (group A) or 120 hours (group B). The main trial included 364 infants. Of these, 194 were screened, 10 declined consent, and 120 met all predefined inclusion criteria. A total of 112 (90%) had complete data for death or disability. Data were analyzed from January 2018 to January 2020. Interventions: Serial amplitude electroencephalography recordings were compared in the 12 hours prior and 12 hours during rewarming for evidence of electrographic seizure activity by 2 central amplitude-integrated electroencephalography readers blinded to treatment arm and rewarming epoch. Odds ratios and 95% CIs were evaluated following adjustment for center, prior seizures, depth of cooling, and encephalopathy severity. Main Outcomes and Measures: The primary outcome was the occurrence of electrographic seizures during rewarming initiated at 72 or 120 hours compared with the preceding 12-hour epoch. Secondary outcomes included death or moderate or severe disability at age 18 to 22 months. The hypothesis was that seizures during rewarming were associated with higher odds of abnormal neurodevelopmental outcomes. Results: A total of 120 newborns (70 male [58%]) were enrolled (66 in group A and 54 in group B). The mean (SD) gestational age was 39 (1) weeks. There was excellent interrater agreement (κ, 0.99) in detection of seizures. More infants had electrographic seizures during the rewarming epoch compared with the preceding epoch (group A, 27% vs 14%; P = .001; group B, 21% vs 10%; P = .03). Adjusted odd ratios (95% CIs) for seizure frequency during rewarming were 2.7 (1.0-7.5) for group A and 3.2 (0.9-11.6) for group B. The composite death or moderate to severe disability outcome at 2 years was significantly higher in infants with electrographic seizures during rewarming (relative risk [95% CI], 1.7 [1.25-2.37]) after adjusting for baseline clinical encephalopathy and seizures as well as center. Conclusions and Relevance: Findings that higher odds of electrographic seizures during rewarming are associated with death or disability at 2 years highlight the necessity of electroencephalography monitoring during rewarming in infants at risk. Trial Registration: ClinicalTrials.gov Identifier: NCT01192776.

  PublisherOA PDFDOI

• Limitations of Conventional Magnetic Resonance Imaging as a Predictor of Death or Disability Following Neonatal Hypoxic–Ischemic Encephalopathy in the Late Hypothermia Trial

  The Journal of Pediatrics · 2020 · 26 citations

  • Medicine
  • Pediatrics
  • Internal medicine
  PublisherOA PDFDOI

• Do Children and Adults Take Social Relationship Into Account When Evaluating People’s Actions?

  Child Development · 2020-08-12 · 39 citations

  article

  Two studies examined whether children (5- and 6-year-olds; 8- and 9-year-olds, n = 214) and adults (n = 72) consider social relationship when evaluating unhelpful or helpful actions. Participants learned about a person-in-need who was (or was not) helped by someone they knew (a friend) and someone they did not know (a stranger). Older children and adults judged an unhelpful friend as meaner than an unhelpful stranger, and judged a helpful stranger as nicer than a helpful friend. Younger children did not judge an unhelpful friend as any meaner than an unhelpful stranger, and they judged a helpful friend as nicer than a helpful stranger. These findings suggest that a mature appreciation of how social relationship matters for evaluation emerges relatively late in development.

  PublisherDOI

• The development of corporal third-party punishment

  Cognition · 2019-05-23 · 13 citations

  article
  PublisherDOI

Recent grants

• Social Evaluation in Infants and Toddlers

  NIH · $2.0M · 2009–2015

• NIH Grant R29HD029857

  NIH · $517k · 1999

Frequent coauthors

• Satyan Lakshminrusimha

  Eunice Kennedy Shriver National Institute of Child Health and Human Development

  52 shared

• Brenda B. Poindexter

  51 shared

• Mary Christensen

  Clinical Trial Investigators

  42 shared

• Gregory M. Sokol

  Research Network (United States)

  40 shared

• Ashley Williams

  Imperial College London

  40 shared

• Betty R. Vohr

  Brown University

  40 shared

• Stephanie A. Wiggins

  Clinical Trial Investigators

  39 shared

• Holly I.M. Wadkins

  Clinical Trial Investigators

  39 shared

Awards & honors

• National Academy of Sciences
• American Psychological Association