Childhood adversity and neural development: Deprivation and threat as distinct dimensions of early experience

In the paper

“children exposed to neglect and poverty often have deficits in language abilities (Farah et al., 2006; Hildyard and Wolfe, 2002) and accompanying differences in neural function supporting language function (Raizada, Richards, Meltzoff, & Kuhl, 2008).”

What the sources say

• Not checked yetcites Farah et al., 2006 source
• Not checked yetcites Hildyard and Wolfe, 2002 source
• Not checked yetcites Raizada, Richards, Meltzoff, & Kuhl, 2008 source

In the paper

“we do not propose that exposure to deprivation and threat experiences occurs independently for children, as most of the exposures described above co-occur. Instead we propose that they can be measured separately and have unique effects on neurodevelopment.”

In the paper

“We suggest that these dimensions of experience can be assessed across different forms of childhood adversity (e.g., physical and sexual abuse, domestic violence, institutionalization, neglect) and will differentially predict aspects of neurodevelopment and ultimately behavior.”

In the paper

“different types of adverse experiences frequently co-occur, meaning that most individuals exposed to childhood adversity have experienced multiple adverse experiences (Dong et al., 2004; Finkelhor et al., 2007; Green et al., 2010; McLaughlin et al., 2012).”

What the sources say

• Not checked yetcites Dong et al., 2004 source
• Not checked yetcites Finkelhor et al., 2007 source
• Not checked yetcites Green et al., 2010 source

In the paper

“it is important to acknowledge that the effects of stress are not fully mediated by cortisol (the most common marker of HPA axis activation in human research) and that cortisol actions on their own do not explain how stress affects gene expression or neuronal plasticity (Gray et al., 2013).”

What the sources say

• Not checked yetcites Gray et al., 2013

In the paper

“exposure to childhood adversity has been shown to explain more than 30% of mental disorders in the U.S. population (Green et al., 2010; McLaughlin et al., 2012)”

What the sources say

• Not checked yetcites Green et al., 2010 source
• Not checked yetcites McLaughlin et al., 2012 source

In the paper

“We argue that these previously undifferentiated dimensions of experience exert strong and distinct influences on neural development that cannot be fully explained by prevailing models focusing only on stress pathways.”

• Also stated in: § Abstract · boosted

  “we propose that these are two dimensions of experience that have not previously been clearly differentiated or explained by prevailing models focused on stress pathways and argue that these dimensions of experience exert strong and distinct influences on neural development.”

In the paper

“Evidence from population-based epidemiological studies indicates that childhood adversity is common and associated strongly with the subsequent onset of psychopathology not only in childhood, but also in adolescence and adulthood (Cohen et al., 2001; Green et al., 2010; Kessler et al., 1997; McLaughlin et al., 2012).”

What the sources say

• Not checked yetcites Green et al., 2010 source
• Not checked yetcites McLaughlin et al., 2012 source

In the paper

“Focusing only on this mechanism is problematic as adversity sometimes appears to have a remarkably broad impact on neurodevelopment.”

In the paper

“We suggest that early threat exposure leads to novel learning, resulting in the pairing of threat cues with previous neutral stimuli, a reduced threshold for experiencing fear, and heightened vigilance to detect other potential threats”

What the sources say

• Not checked yetcites van Marle et al., 2009 source

In the paper

“The vmPFC is activated during retrieval of extinction learning and down-regulates the amygdala”

What the sources say

• Not checked yetcites Milad and Quirk, 2012 source
• Not checked yetcites Milad et al., 2007 source
• Not checked yetcites Quirk et al., 2003 source

In the paper

“learned fear continues to be represented in the amygdala and hippocampus, and previously extinguished fear can be re-activated following exposure to situations where fear learning initially occurred or to other threatening contexts”

What the sources say

• Not checked yetcites Bouton, 2002 source
• Not checked yetcites Bouton et al., 2006 source
• Not checked yetcites Rescorla, 2004 source

In the paper

“First, we predict that early threat exposure leads to changes in hippocampal morphology and function, including reduced dendritic spines and arborization and poor function in hippocampus-dependent learning and memory tasks.”

In the paper

“Behaviorally, this results in heightened attention to threat-related cues, generalization of learned fear to previously neutral stimuli, and elevated emotional responses to a wide range of emotional cues.”

In the paper

“extinguished fear can be re-activated through a variety of processes, including spontaneous recovery, exposure to novel threats, exposure to the CS in novel contexts, or re-exposure to the US”

What the sources say

• Not checked yetcites Bouton, 2002 source
• Not checked yetcites Bouton, 2004 source
• Not checked yetcites Bouton and King, 1983

In the paper

“We expect that reductions in cortical thickness should be most pronounced in regions of association cortex that are recruited for processing complex social and cognitive inputs, including prefrontal cortex (PFC), superior and inferior parietal cortex, and superior temporal cortex.”

In the paper

“Fear is a defensive mechanism that activates behavioral and neurobiological responses to danger that promote survival, including freezing and activation of sympathetic nervous system and HPA axis”

What the sources say

• Not checked yetcites LeDoux, 2003 source

In the paper

“When neglect is directly compared to abuse, children exposed to neglect are at greater risk for cognitive deficits than children exposed to abuse (Hildyard & Wolfe, 2002) and these deficits are similar to those observed in severe poverty and institutionalization (Dubowitz et al., 2002; Spratt et al., 2012), consistent with our conceptualization of neglect as a form of deprivation.”

What the sources say

• Not checked yetcites Hildyard & Wolfe, 2002 source
• Not checked yetcites Dubowitz et al., 2002 source
• Not checked yetcites Spratt et al., 2012 source

In the paper

“The vmPFC is thus essential for retention of extinction learning and inhibition of fear”

What the sources say

• Not checked yetcites Phelps et al., 2004 source
• Not checked yetcites Quirk et al., 2000 source

In the paper

“Together, these changes result in elevated amygdala activation to emotional stimuli due to the increased salience of such information, and potentially as a result of up-regulation of CRH receptors in the amygdala”

What the sources say

• Not checked yetcites Hatalski et al., 1998 source

In the paper

“low SES is associated with decreased performance on complex cognitive tasks, including those tapping executive function and long-term memory (Evans and Schamberg, 2009; Farah et al., 2006; Hackman et al., 2010; Kishiyama et al., 2009; Noble et al., 2007), language ability (Fernald et al., 2013; Weisleder and Fernald, 2013), and overall cognitive and academic achievement (Brooks-Gunn and Duncan, 1”

What the sources say

• Not checked yetcites Evans and Schamberg, 2009 source
• Not checked yetcites Farah et al., 2006 source
• Not checked yetcites Hackman et al., 2010 source

In the paper

“An extensive literature in rodents has characterized the neural circuitry that underlies fear learning using Pavlovian fear conditioning tasks”

What the sources say

• Not checked yetcites Johansen et al., 2011 source
• Not checked yetcites Kim and Jung, 2006
• Not checked yetcites LeDoux, 2003 source

In the paper

“potential threats activate the hypothalamic-pituitary-adrenal (HPA) axis, leading to enhanced expression of corticotropin releasing hormone (CRH) in the hippocampus and damage to hippocampal neurons (Brunson et al., 2001; Ivy et al., 2010).”

What the sources say

• Not checked yetcites Brunson et al., 2001 source
• Not checked yetcites Ivy et al., 2010 source

In the paper

“early threat exposure has consistently been associated with reduced hippocampal volume in adults (Andersen and Teicher, 2008; Hart and Rubia, 2012; Teicher et al., 2012), studies of children have generally not found a relationship between threat exposure and hippocampal volume”

What the sources say

• Not checked yetcites Andersen and Teicher, 2008 source
• Not checked yetcites Hart and Rubia, 2012 source
• Not checked yetcites Teicher et al., 2012 source

In the paper

“Taken together, the rodent literature suggests that early exposure to uncontrollable threat results in long-term changes in hippocampal and amygdala structure and function as well as deficits in inhibitory control of these regions by the mPFC.”

In the paper

“These environments share the characteristic of being significant threats to survival and therefore activate the neural circuitry underlying fear learning.”

In the paper

“Extinction of conditioned fear initially requires the amygdala, whereas retrieval of extinction memory on subsequent days additionally requires the vmPFC”

What the sources say

• Not checked yetcites Falls et al., 1992 source
• Not checked yetcites Morgan et al., 1993 source
• Not checked yetcites Quirk et al., 2000 source