Can we identify biological markers of risk and resilience related to the intergenerational transmission of risk?

1. Can we identify biological markers of risk and
resilience related to the intergenerational
transmission of risk?
Andrea Gonzalez
Offord Centre for Child Studies
Department of Psychiatry & Behavioural Neurosciences

3. (Affifi et al., 2011; Cicchetti & Toth, 2005; Gilbert et al., 2009; Gonzalez, 2013)
Child Outcomes
G1
G2

4. Macrosystem
Exosystem
Mesosystem
Microsystem

5. Early Adversity

6. Mechanism of Transmission
• In animals: proposed mechanisms are
physiological and include changes in:
Hypothalamic-pituitary-adrenal (HPA) function,
serotonergic function and changes in brain
plasticity (Burton et al., 2007; Kaffman & Meaney, 2007;
Maestripieri et al., 2007)
• In humans: proposed mechanisms have
originated from social learning or
attachment and include:
– Observational learning, role-modeling, and transmission
via internal representations (Pullatz et al., 2004; Serbin & Karp,
2004; van IJzendoorn, 1992)

7. Proposed Model in Humans

8. Stress System:
the Hypothalamic-Pituitary Adrenal (HPA) axis

9. Executive Function
Wisconsin Card Sorting Test
Stroop/ Color-Word Inhibition
Set shifting/Cognitive Flexibility
Tower Test
Spatial planning/inhibition
Spatial span/digit span

10. Maternal early
adversity
HPA function
Executive function
Maternal
sensitivity
0.22** -0.22*
0.22*
-0.33**
*p<.05 **p< .01χ2= 5.53; CFI = .98, RMSEA = .06
Gonzalez et al., 2012 JAACAP

11. Why does this matter? Transmission
beyond mom...?

13.  Developing HPA axis is strongly influenced by social
factors throughout infancy
 In high-risk populations evidence of transmission of
HPA activity to offspring:
• Offspring of Holocaust survivors (with parental PTSD)
had significantly lower diurnal cortisol levels (Yehuda et
al., 2006)
• Infants whose mothers developed PTSD after 9/11 had
lower diurnal cortisol levels compared to infants with
mothers without PTSD (Yehuda & Bierer, 2008)

14. Parenting and Infant Cortisol Reactivity
Atkinson et al., 2013; Psychoneuroendocrinology
Mothers and infants’ baseline cortisol levels were positively
related, r = .53* and their slopes were positively related, r = .60*

15. Transmission of Executive Function?
3-months:
Maternal
history of
childhood
maltreatment
8-months:
Maternal executive
function and
parenting
18-
months:
Infant
Cognition
3-years:
Child
executive
function

16. Child cognitive function: 18-months
F(6, 104) = 2.26, p <.05

18. Child Executive Function: 3 years

19. Summary

20. Gonzalez, Atkinson, & Fleming, 2009
Parenting Brain Recruits Multiple Systems
• Adaptive parenting
requires a
constellation of
capacities including
effective stress
regulation, attentional
control, emotion
regulation and
executive function.
Infant cues
EF performance

21. Early
Adversity
• Recent imaging studies have
implicated these same areas as
vulnerable sites to the effects
of early adversity, including
the DLPFC, ACC, OFC, mPFC,
the hippocampus and the
amygdala (Hart & Rubia, 2012)

22. Summary
• Early adversity and its impact on biological
systems may mediate or moderate deficits
related to poor parenting and subsequent
offspring outcomes
• Understanding the role that these systems plays
may help in the understanding of the
intergenerational transmission of risk

23. Intervention Implications
• Psycho-educational
interventions is likely not be
enough to improve parenting
and child outcomes for all
families
• Potential for innovative
interventions to target
underlying neurocognitive
functions and stress system in
parents and associated
competencies in children
• Empirical question whether
interventions should target
these core capabilities explicitly
or implicitly (Shonkoff & Fisher,
2014)

24. Acknowledgements: Collaborators, Staff,
Students, and Participating Families
• Collaborators
• Harriet MacMillan (McMaster)
• Leslie Atkinson (Ryerson)
• Susan Jack (McMaster)
• Geoff Hall (McMaster)
• Margaret McKinnon (McMaster)
• Christine Wekerle (McMaster)
• Staff/students
• Rebecca Lowe
• Monica Ivan
• Gillian-England Mason
• Samantha Daniels
• All the mothers and infants who participated in the studies