Heritability & Genetics
TRUE OR FALSE?
Heritability can dynamically change over lifespan, as different genetic pathways come on- or off-line.
True!
Lost opportunities to acquire critical social skills are associated with which childhood trait?
behavioral inhibition
How does uncertainty influence anxiety *AND* how have scientists measured this?
Uncertainty increases anxiety, as indexed by fear-potentiated startle (Curtin), ratings (Curtin), behavior in the elevated plus maze (Herry), attentional biases to angry faces on the dot-probe task (Herry), etc.
What are some limitations of self-report measures of T&P?
Are trait-like differences in T&P discernible in the on-going, spontaneous activity of the brain?
Yes!
TRUE OR FALSE:
FALSE! (Corn Stalks Example)
Roughly what % of children with stable and extreme behavioral Inhibition (BI) develop social anxiety disorder later in life?
~45% … nearly half
What is attentional bias modification and is it effective?
It is the retraining attentional biases to threat (dot is consistently paired with the location of the neutral stimulus). ABM reduces anxiety in the lab (e.g. in a public speaking task) and clinician ratings of anxiety in the real world, suggesting that it is an "active ingredient" in the development of extreme anxiety
What are some limitations to animal models?
Animal modes cannot tell us about subjective experience and feelings.
There is no DSM for animals, you can only model a subset of the symptoms that characterize a particular disorder
What are some consequences of amygdala damage in humans?
- Cannot acquire new fear learning [Adolphs/Damasios]
- Reduced fear/anxiety (pet store, haunted house) [Feinstein/Adolphs]
- Problems learning to avoid danger (mugging/park) [Feinstein/Adolphs]
- Increased social approach ('close talker') [Kennedy/Adolphs]
- And a whole slew of other deficits, suggesting that the amygdala does much more than simply orchestrate fear/anxiety
What is heritability AND is it synonymous (the same as) genetic basis .... meaning: can you have traits or phenotypes that built according to genetic recipes, yet have a heritability of ~0?
What factors contribute to the emergence of social anxiety disorder in children marked by stable, high levels of behavioral inhibition?
‘Helicopter’ parenting and other well-intentioned but maladaptive forms of nurture and exposure to more extreme negative life events, stress, trauma, or adversity
In cross-sectional studies and in prospective longitudinal studies elevated levels of N/NE predict what?
future emotional disorders and symptoms of anxiety and depression [e.g. Jeronimus meta-analysis]
What is the skin conductance response?
Changes in the skin's resistance. Sweaty palms (arousal) reduce the skin's resistance, increasing conductance. A widely used measure of arousal that can be used to index emotional learning e.g. conditioned emotional response during Pavlovian fear conditioning experiments
What does the Adaptive Control Hypothesis claim about the mid-cingulate cortex (MCC)?
Anxiety, pain, and cognition engage a common territory in the MCC
AND
The MCC is a neural hub that uses information about pain, negative affect, threat, errors, and negative feedback to optimize behavior in the face of uncertainty about actions and their potentially aversive outcomes
How does experience (e.g. maternal nurture) get 'under the skin' and produce long-lasting differences in emotional traits?
Changes in the epigenome alter the expression of genes --> leading to changes in protein synthesis --> changes in brain structure and function (glu receptors in the hippo; BDZ receptors in the amygdala) --> persistent alterations in behavior and stress reactivity [Meaney]
When Behavioral Inhibition (BI) is _________ and ____________ it confers ______ risk for developing psychopathology.
Stable; high; increased
According to Barlow and Shackman: Anxiety disorders, depression, and N/NE share ....?
Why do ‘excitotoxic’ (ibotenic acid) lesions enable more specific inferences?
Because they spare axons passing through the targeted region (‘fibers of passage’)
Where do individual differences in brain structure and function come from?
Genome/DNA
Experience
Experience interacting with the epigenome to alter gene expression and protein synthesis
What is the 4th law of behavioral genetics AND can small correlations in a GWAS identify potentially interesting and important (e.g. druggable) targets, or are they practically worthless?
The vast majority of human traits and phenotypes associated with very many genetic variants, each of which account for a small percentage of variance; highly polygenic
Yes. Small SNP associations can be used to identify genetic loci that have very large effects on the trait or phenotype (e.g. cholesterol) when that molecular pathway is directly manipulated [Statin example]
In youth, behavioral inhibition (BI) shows ___ test-retest stability. This likely reflects the fact that extreme BI early in development likely reflects a _____ of kids, some with _____ disposition that confers ____ and some with _______ fears.
Modest; mixture; an extreme; increased risk; age-appropriate
How do avoidant thoughts and behaviors promote pathological anxiety?
Prevent exposure to evidence that may contradict negative predictions about the future
Are reinforced because events that are avoided tend to not occur thus continuing cycle of avoidance
What's problematic about unpublished null results (the so-called ‘file drawer problem’)?
Unpublished null results bias scientific literature, such that narrative reviews and quantitative meta-analyses systematically over-estimate the size of an effect (such as the association between N/NE and amygdala reactivity or likelihood of developing depression)
What do control-related signals (e.g., error-related negativity/ERN) predict? And what does this suggest?
LAB: increased caution, reticence, and instrumental avoidance. CLINIC: 1st emergence of anxiety disorders in youth, esp among those exposed to Hurricane Sandy; ERN also discriminates anxiety patients from controls, and scales with the intensity of GAD symptoms
SUGGESTS: a neural circuit centered on the MCC (the region that generates the ERN) causally contributes to the development of pathological avoidance and anxiety; "active ingredient"