Julie Boulanger Bertolus - Academia.edu (original) (raw)

Papers by Julie Boulanger Bertolus

Research paper thumbnail of Updating temporal expectancy of an aversive event engages striatal plasticity under amygdala control

Nature communications, Jan 9, 2017

Pavlovian aversive conditioning requires learning of the association between a conditioned stimul... more Pavlovian aversive conditioning requires learning of the association between a conditioned stimulus (CS) and an unconditioned, aversive stimulus (US) but also involves encoding the time interval between the two stimuli. The neurobiological bases of this time interval learning are unknown. Here, we show that in rats, the dorsal striatum and basal amygdala belong to a common functional network underlying temporal expectancy and learning of a CS-US interval. Importantly, changes in coherence between striatum and amygdala local field potentials (LFPs) were found to couple these structures during interval estimation within the lower range of the theta rhythm (3-6 Hz). Strikingly, we also show that a change to the CS-US time interval results in long-term changes in cortico-striatal synaptic efficacy under the control of the amygdala. Collectively, this study reveals physiological correlates of plasticity mechanisms of interval timing that take place in the striatum and are regulated by th...

Research paper thumbnail of Ecologically relevant neurobehavioral assessment of the development of threat learning

Learning & Memory, 2016

As altricial infants gradually transition to adults, their proximate environment changes. In thre... more As altricial infants gradually transition to adults, their proximate environment changes. In three short weeks, pups transition from a small world with the caregiver and siblings to a complex milieu rich in dangers as their environment expands. Such contrasting environments require different learning abilities and lead to distinct responses throughout development. Here, we will review some of the learned fear conditioned responses to threats in rats during their ontogeny, including behavioral and physiological measures that permit the assessment of learning and its supporting neurobiology from infancy through adulthood. In adulthood, odor-shock conditioning produces robust fear learning to the odor that depends upon the amygdala and related circuitry. Paradoxically, this conditioning in young pups fails to support fear learning and supports approach learning to the odor previously paired with shock. This approach learning is mediated by the infant attachment network that does not include the amygdala. During the age range when pups transition from the infant to the adult circuit (10-15 d old), pups have access to both networks: odor-shock conditioning in maternal presence uses the attachment circuit but the adult amygdala-dependent circuit when alone. However, throughout development (as young as 5 d old) the attachment associated learning can be overridden and amygdala-dependent fear learning supported, if the mother expresses fear in the presence of the pup. This social modulation of the fear permits the expression of defense reactions in life threatening situations informed by the caregiver but prevents the learning of the caregiver itself as a threat.

Research paper thumbnail of Infant rats can learn time intervals before the maturation of the striatum: evidence from odor fear conditioning

Frontiers in Behavioral Neuroscience, 2014

Research paper thumbnail of Enduring Neural and Behavioral Effects of Early Life Adversity in Infancy: Consequences of Maternal Abuse and Neglect, Trauma and Fear

Early life experiences have long-lasting influence on a child. For an infant, the quality of care... more Early life experiences have long-lasting influence on a child. For an infant, the quality of caregiving is one of the most critical factors supporting growth and development. Adverse social events in infancy have the potency to alter the child’s developmental trajectory and elevate the lifetime risk for a range of psychiatric disorders. Although clinical studies associate early childhood adversities with lifetime risk for mental disorders, the knowledge of underlying neural and molecular alterations leading to these disorders comes mostly from animal studies. In this article, we overview selected animal models of early life social adversity, including maternal abuse and neglect, and maternal trauma and fear. We first characterize the major behavioral and neural changes normally occurring in early life. We then present several animal models of maternally mediated early life adversity that contribute to reorient the developmental changes toward pathological outcomes. These models yielded to recently identified neurobiological mechanisms, including epigenetic alterations, through which these adversities lead to a lasting dysregulation of the stress response system, aberrant fear learning and memory, and increased anxiety or depression-like behaviors.

Research paper thumbnail of Updating temporal expectancy of an aversive event engages striatal plasticity under amygdala control

Nature communications, Jan 9, 2017

Pavlovian aversive conditioning requires learning of the association between a conditioned stimul... more Pavlovian aversive conditioning requires learning of the association between a conditioned stimulus (CS) and an unconditioned, aversive stimulus (US) but also involves encoding the time interval between the two stimuli. The neurobiological bases of this time interval learning are unknown. Here, we show that in rats, the dorsal striatum and basal amygdala belong to a common functional network underlying temporal expectancy and learning of a CS-US interval. Importantly, changes in coherence between striatum and amygdala local field potentials (LFPs) were found to couple these structures during interval estimation within the lower range of the theta rhythm (3-6 Hz). Strikingly, we also show that a change to the CS-US time interval results in long-term changes in cortico-striatal synaptic efficacy under the control of the amygdala. Collectively, this study reveals physiological correlates of plasticity mechanisms of interval timing that take place in the striatum and are regulated by th...

Research paper thumbnail of Ecologically relevant neurobehavioral assessment of the development of threat learning

Learning & Memory, 2016

As altricial infants gradually transition to adults, their proximate environment changes. In thre... more As altricial infants gradually transition to adults, their proximate environment changes. In three short weeks, pups transition from a small world with the caregiver and siblings to a complex milieu rich in dangers as their environment expands. Such contrasting environments require different learning abilities and lead to distinct responses throughout development. Here, we will review some of the learned fear conditioned responses to threats in rats during their ontogeny, including behavioral and physiological measures that permit the assessment of learning and its supporting neurobiology from infancy through adulthood. In adulthood, odor-shock conditioning produces robust fear learning to the odor that depends upon the amygdala and related circuitry. Paradoxically, this conditioning in young pups fails to support fear learning and supports approach learning to the odor previously paired with shock. This approach learning is mediated by the infant attachment network that does not include the amygdala. During the age range when pups transition from the infant to the adult circuit (10-15 d old), pups have access to both networks: odor-shock conditioning in maternal presence uses the attachment circuit but the adult amygdala-dependent circuit when alone. However, throughout development (as young as 5 d old) the attachment associated learning can be overridden and amygdala-dependent fear learning supported, if the mother expresses fear in the presence of the pup. This social modulation of the fear permits the expression of defense reactions in life threatening situations informed by the caregiver but prevents the learning of the caregiver itself as a threat.

Research paper thumbnail of Infant rats can learn time intervals before the maturation of the striatum: evidence from odor fear conditioning

Frontiers in Behavioral Neuroscience, 2014

Research paper thumbnail of Enduring Neural and Behavioral Effects of Early Life Adversity in Infancy: Consequences of Maternal Abuse and Neglect, Trauma and Fear

Early life experiences have long-lasting influence on a child. For an infant, the quality of care... more Early life experiences have long-lasting influence on a child. For an infant, the quality of caregiving is one of the most critical factors supporting growth and development. Adverse social events in infancy have the potency to alter the child’s developmental trajectory and elevate the lifetime risk for a range of psychiatric disorders. Although clinical studies associate early childhood adversities with lifetime risk for mental disorders, the knowledge of underlying neural and molecular alterations leading to these disorders comes mostly from animal studies. In this article, we overview selected animal models of early life social adversity, including maternal abuse and neglect, and maternal trauma and fear. We first characterize the major behavioral and neural changes normally occurring in early life. We then present several animal models of maternally mediated early life adversity that contribute to reorient the developmental changes toward pathological outcomes. These models yielded to recently identified neurobiological mechanisms, including epigenetic alterations, through which these adversities lead to a lasting dysregulation of the stress response system, aberrant fear learning and memory, and increased anxiety or depression-like behaviors.