Mothers exposed to traumatic events in early life, including episodes of interpersonal violence, go on to develop violence-related posttraumatic stress disorder (PTSD) that can trigger several disturbances, including increased difficulty in parenting their toddlers (see Figure 1). The mother-child relationship is paramount for the emotional, social and cognitive outcome of the child and traumatized mothers may influence the developmental psychopathology of their child.
Figure 1: PTSD mother having difficulty parenting her toddler (Image Credit: Professor Daniel Schechter, HUG).
This is the main research problem Daniel Schechter and François Ansermet are looking into the scope of the fourth Synapsy clinical research project. Daniel Schechter’s team is based at the Geneva University Hospitals and their major concern is mothers exposed to interpersonal violence (IPV) during adulthood and how this violence, often following earlier childhood abuse can lead to the development of PTSD. Francois Ansermet and teams are at the Centre Hospitalier Universitaire Vaudois and are concentrating their efforts on mothers exposed to the stress of having premature babies, particularly those requiring intensive care.
The Mother-Child Relationship: A Boomerang Effect
Several questions intrigue the Genevois and Vaudois clinicians. One is to know how the mother’s PTSD affects her “reading” of her child’s emotional communication. Related to this question, they would like to understand how the child’s behavior might in turn affect the mother, “Could an infant’s distress, anxiety, anger or helplessness trigger PTSD symptoms in the mother?” Daniel Schechter asks.
The clinicians also want to understand the emotional response and interactive behavior of the mothers in a situation in which the child is exposed to violent moments. Their hypothesis is that traumatized mothers play a significant role in the increased behavioral disturbances observed in their children following their own exposure to violence. If mothers can be helped to find their capacity to identify their child’s and their own emotions, to attribute mental states to others and themselves that might motivate interactive behavior, child resilience may be possible. Otherwise an attachment disturbance may become entrenched and lead to subsequent psychiatric problems such as anxiety and mood disorders as well as PTSD.
An important aim is to understand the process of intergenerational transmission of trauma. “We need to identify maternal behavioral signs and endophenotypes that might contribute to knowing whether a child will be at risk to become aggressive, victimized or resilient”.
Behavior, Physiology and Genetics of PTSD Investigated
The first phase of the team’s study concentrated on the child’s critical period for the development of social cognition and emotion regulation between 12 and 42 months, a time when children start to walk and distance themselves from their mother in an attempt to actively explore their environment. This period is characterized by peaks of anger and separation anxiety, topsy-turvy emotion. “It presents an ideal time to observe how the mothers are able to deal with the negative emotions of their offspring,” says Daniel Schechter.
The clinicians first evaluated the mother’s mental representations of her child, her life-event history and her psychopathology. Mothers and children were then welcomed to a laboratory playroom where they were observed by videotaping. They were filmed in their new environment where they could interact with age-appropriate toys (free-play). This was followed by a planned separation in which the mother was given a signal to leave the room and asked to wait outside the door for three minutes. “The reunion that follows is always an important moment. We look at how the mother handles her child’s reaction to the separation and how she reorients the child to playing again” indicates Daniel Schechter. Additional activities are then observed such as tidying-up and structured-play; exercises somewhat above the child’s developmental capacity, needing help from the mother. For the second mother-child separation that follows, only these challenging activities remain in the room, making the separation potentially more distressing for the child. After observing the second reunion, the researchers then investigate how the child and mother interact together when exposed to novel situations such as a clown entering the room with a noisemaker or a roaring mechanical dinosaur robot. “In these moments, we look at how the child copes with excitement, surprise, joy and fear and if and how the mother tries to reassure her child in the new situations”. In addition to behavioral studies, the clinicians also look for possible epigenetic and physiological endophenotypes associated with maternal behavior. For this, cortisol measurements were done every 30 minutes and additional saliva was collected to extract DNA for gene methylation analysis. Furthermore, structural and functional MR imaging was carried out on the mothers while observing videos of free-play and separation with their own child and a non-related child to look for differences in neural activity in PTSD versus non-PTSD mothers-a sort of a “neural footprint”.
A Mother’s Stress Puts Her Child at Risk
The researchers then investigated if the emotional and physiological disturbances observed among PTSD mothers were also mirrored by “corticolimbic dysregulation” within their brains. In particular, the medial prefrontal cortex is known to be involved in top-down emotion regulation. Mothers with PTSD related to a history of interpersonal violence displayed less neural activity in these regions (see Figure 2) than control mothers in response to seeing film-excerpts of their own and unfamiliar children during separation (stressful condition) versus play (non-stressful condition). “This finding supports the notion that the child itself can trigger the cortico-limbic dysregulation as a marker of PTSD symptoms in the maternal brain.”
Figure 2: Functional Magnetic Resonance images of mothers’ brains showing a positive correlation of HTR3A methylation and neural activity (salmon color, dorso-medial prefrontal cortex). Yellow and magenta colors correspond to negative correlations (Image Credit: Professor Daniel Schechter, HUG).
Physiological differences are also seen in PTSD mothers who show a much lower waking salivary cortisol level compared to control mothers. Further, while children of non-PTSD mothers (“controls”) show a typical stress response 30 minutes after the separation-stressor, the children of PTSD mothers show virtually no reactivity. “This discovery reveals that there are physiological differences in the offspring of PTSD mothers already at 12–42 months of age”. Epigenetic modifications marked by decreased methylation of the glucocorticoid receptor gene, NR3C1, as well as the serotonin receptor, HTR3A (see Figure 2) were observed in maternal PTSD brains. “The results all point in the same direction: there is a link between genetics, physiology, neural activity and behavior.”
A Follow-up of the Child to Adolescence
The second phase of the project started in February 2016 and involves examining the same children using school-age appropriate measures when they are 5 to 9 years old. Between these ages, typical children have already acquired a firm foundation of social cognition and can begin to mentalize, self-regulate their emotions, arousal, and aggression. Child neuroimaging using high-density electroencephalography (HD-EEG) is now included in a collaboration with Christophe Michel’s group, for the longitudinal follow-up of these children. The goal is to understand how the children interpret emotions and to determine whether a long-term biological “signature” can be defined in the children from mothers with IPV-PTSD, who may also have been directly affected by violence and that could be used to predict whether the child will more likely become victim or perpetrator of violence or neither of the two (i.e. resilient).
The peri-pubertal period of development will be the focus of the third Synapsy project phase. This period is again critical in child development as a result of the many hormonal changes involved, as well as the development of the medial prefrontal cortex and related circuits. “We would like to know if puberty acts on PTSD and underlying mentalization and abstract thought capacities within the frame of these developmental events,” indicates Daniel Schechter.
Treatment, the Guide and the Influence
In the end, the most meaningful challenge for the clinical researchers is to generate effective treatments based on the evidence produced from their studies. What kind of interventions can be used to target the emotional/behavioral, physiologic and cortico-limbic dysregulation that Daniel Schechter has described? “Therapists can stimulate maternal mentalization by working closely with mothers to help them think about what was going on in their own and their child’s minds during the filmed interactions (i.e. play, separations, reunions, exposure to novelty). They ask mothers to try to interpret what their child might be thinking and feeling during these moments and indeed, how these processes might inform on their child’s (and their own) behavior.” With this type of intervention that helps mothers “change their minds about their young child,” a mother’s perceptions of her child can become less negative and more appropriate for the child’s age. “The IPV-PTSD mothers tend to have difficulty identifying emotions and in particular confuse anger and fear as well as control and helplessness. We can help to reduce this confusion using this novel technique of clinician-assisted video-feedback exposure.” Schechter and colleagues are currently finishing a brief psychotherapy manual based on this technique and that will soon be ready for experimental trials. These trials provide a real hope for treatment for these families at high-risk of intergenerational violence and trauma.