Early adversity and learning: implications for typical and atypical behavioral development.
BACKGROUND
Children who experience early adversity often develop emotion regulatory problems, but little is known about the mechanisms that mediate this relation. We tested whether general associative learning processes contribute to associations between adversity, in the form of child maltreatment, and negative behavioral outcomes.


METHODS
Eighty-one participants between 12 and 17 years of age were recruited for this study and completed a probabilistic learning Task. Forty-one of these participants had been exposed to physical abuse, a form of early adversity. Forty additional participants without any known history of maltreatment served as a comparison group. All participants (and their parents) also completed portions of the Youth Life Stress Interview to understand adolescent's behavior. We calculated measures of associative learning, and also constructed mathematical models of learning.


RESULTS
We found that adolescents exposed to high levels of adversity early in their lives had lower levels of associative learning than comparison adolescents. In addition, we found that impaired associative learning partially explained the higher levels of behavioral problems among youth who suffered early adversity. Using mathematical models, we also found that two components of learning were specifically affected in children exposed to adversity: choice variability and biases in their beliefs about the likelihood of rewards in the environment.


CONCLUSIONS
Participants who had been exposed to early adversity were less able than their peers to correctly learn which stimuli were likely to result in reward, even after repeated feedback. These individuals also used information about known rewards in their environments less often. In addition, individuals exposed to adversity made decisions early in the learning process as if rewards were less consistent and occurred more at random. These data suggest one mechanism through which early life experience shapes behavioral development.
Department of Psychology, University of Wisconsin-Madison, Madison, WI, USA.|Waisman Center, University of Wisconsin-Madison, Madison, WI, USA.
Jamie L
http://orcid.org/0000-0002-0469-8886
JL
Hanson
Center for Adaptive Rationality, Max Planck Institute for Human Development, Berlin, Germany.
Wouter
http://orcid.org/0000-0002-8017-3790
W
van den Bos
Waisman Center, University of Wisconsin-Madison, Madison, WI, USA.
Barbara J
BJ
Roeber
Department of Psychology, University of Illinois at Urbana-Champaign, Champaign, IL, USA.
Karen D
KD
Rudolph
Department of Psychology, University of Wisconsin-Madison, Madison, WI, USA.|Waisman Center, University of Wisconsin-Madison, Madison, WI, USA.
Richard J
RJ
Davidson
Department of Psychology, University of Wisconsin-Madison, Madison, WI, USA.|Waisman Center, University of Wisconsin-Madison, Madison, WI, USA.
Seth D
SD
Pollak
D000293:Adolescent; D000294:Adolescent Behavior / Q000502:physiology*; D001245:Association Learning / Q000502:physiology*; D002648:Child; D002649:Child Abuse; D003657:Decision Making / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D011337:Probability Learning; D000066553:Problem Behavior; D012201:Reward
Learning; child abuse; child development; early life experience; social behavior