Cumulative Review
Based on his work with the Fore people of Papua New Guinea, Ekman suggested that the rules for signaling and decoding emotions are ___ and (hence) ____.
Universal and (hence) Innate
Which division of the autonomic nervous system is known for "rest and digest" ? Which is known for "fight or flight"?
R&D = Parasympathetic NS
F&F = Sympathetic NS
Heritability describes ______, not __________ be.
- what is (current population under study)
- what could be (different/future populations)
A SNP is the most common kind of ____, which underlie ________ .
Allele (genetic variant/polymorphisms, which underlie individual differences in traits and phenotypes
Trait-like differences in T&P reflect the brain. Individual differences in brain structure and function reflect the influence of _______. [Name at least 3]
-Genome/DNA/Nature
-Experience/Environment/Nurture
-Epigenetic regulation
-Experience interacting with the epigenome to alter gene expression and, ultimately, the proteins that make up neurons and other cellular building blocks
What is the value of computing a correlation using 20,000 (Swedish) observations, rather than 25?
more
- power to detect modest associations
- precision ... leading to a more stable and reproducible literature
Astrocytes and oliogodendrocytes are types of glia. Briefly explain their functions.
Astrocytes
- maintain the blood-brain barrier (BBB)
- bonus: play a role in the delivery of glucose and oxygen to neurons (hence, underlie fMRI and FDG-PET signals)
Oliogodendrocytes
- myelinate neurons in the central nervous system...massively increasing speed/reliability and decreasing energetic costs of action potentials
What is heritability? Briefly explain.
-The proportion of variation in a trait, such as C/SC, that is explained by the biological pedigree (family tree; e.g. mid-parental height)
-Genetic variance divided by total trait variance (GV/TTV)
Pick 1: Information gleaned from large-scale GWAS (A) Is being incorporated into clinical practice for some physical disorders and treatments, with others on the horizon. (B) Has never been incorporated into clinical practice, and probably never will be. (C) Has never been incorporated into clinical practice, but will be at some point in the future. (D) Is already a regular part of clinical practice for a wide range of psychiatric and non-psychiatric disorders
A. Is being incorporated into clinical practice for some physical disorders and treatments, with others on the horizon
How does experience (abuse, stress, caregiver behavior) get ‘into the brain’ in the space of a single lifetime?
Changes in the epigenome that alter the expression of genes, leading to changes in protein synthesis and, ultimately, brain structure/activity (and, hence, mental states & traits!)
Venus is an expert psychometrician. A colleague asks her for some advice about the best way to assess the test-retest stability of individual differences in E/PE. Which statistical test should Venus recommend?
Test-retest correlation (or ICC)
Name the parts of a generic neuron, and describe how neuronal signals get from one end of the neuron to the other
Dendrite (Post-Synaptic Receptors) -> Soma (Nucleus makes Proteins) -> Axon Hillock (dimensional changes in membrane potential are integrated; all-or-nothing AP) --> Axon (Myelinated: Salatatory...Nodes of Ranvier) --> Terminal or Bouton (NT-filled vesicles can fuse w/ the membrane and dump NT molecules into the cleft where they diffuse to the neighboring post-synaptic neuron to bind w/ post-synaptic receptors)
Describe the 4th law of behavioral genetics.
A typical human trait is associated with many genetic variants, each of which account for a very small percentage of variance in the trait.
3 Parts: What is a GWAS? Name 1 advantage and 1 weakness of GWAS.
Genome-wide association study: Brute force discovery approach (no hypothesis necessary) to identifying correlations between millions of SNPs and traits/disorders
-Suffers from low statistical sensitivity, because of the very large number of tests performed
- Shares some of the limitations of non-molecular heritability estimates derived from Family & Twin studies (e.g. assumes no G-E interactions/G-E correlations)
- Until ~2024, mostly based on studies of White European ancestry participants, with unclear or degraded utility for taxpayers and healthcare consumers with other ancestries
Based on the latest and greatest science circa 2023, what do we know about the association between the serotonin transporter polymorphism (5-HTTLPR) & amygdala activation (measured using fMRI)?
They are *not* significantly related!
Note: This goes against hypotheses put forth by Hariri and Caspi
Bonus: 5-HTTLPR is also not related to 5-HTT expression in the amygdala (per Ned Kalin)
What is 1 key advantage and 1 key downside of a prospective-longitudinal study design (e.g., the Dunedin study)?
Provide compelling evidence that antecedents in childhood predict consequences in adulthood, a precondition for establishing causation
Downsides - cost, complexity, possibility of differential attrition (e.g. all of the low C/SC Ss drop-out)
Neurotransmitter molecules spill out of fused vesicles into the synaptic cleft. How is chemical neurotransmission regulated and stopped? Name at least 2 of the 3 governing processes.
- Active reuptake (“transport”) into the presynaptic neuron
- Enzymatic degradation and break-down
- Passive diffusion
Heritability estimates derived from family, twin, and adoption studies reflect ______________ that blood relatives share (name at least 2)
Genes AND everything else blood relatives share e.g. political attitudes, religions, occupations, neighborhoods, SESs, diet, access to resources, access to illicit substances, exposure to violence and war
Genes __________ code for specific behaviors (e.g. calculus) or psychological traits (e.g. N/NE). They code for _______, which in turn make up __________ .
- don't
- proteins
- brains (nervous systems, neurons, myelin, etc.)
2-Part: A wide variety of environmental factors (e.g. family conflict, marriage, religiosity, parental monitoring, delinquent peers) can ________ genetic predispositions. Is there credible, reliable evidence that molecular G-E interactions moderate depression risk?
1) Regulate: Unmask, amplify, or compensate for genetic predispositions (Technical term "moderate"; G-E interaction)
2) Yes, recent Big-N research by Ken Kendler and pals
Lisa Feldman Barrett tells us that the Triggers, Functions, and _______ of emotions are massively heterogeneous and highly dependent on the _______ of the organism and environment...Like snowflakes
- Expressions (or) Biological Substrates
- Local Context and Life History (e.g. opportunity for escape, degree of hunger, culture, etc.)
Receptor Ligands: In class, we talked about agonists, indirect agonists, antagonists, and inverse agonists. What does each type of ligand do?
- "Agonists" increase signaling by binding to and activating receptors.
- "Indirect agonists" increase signaling by binding to transporters and blocking reuptake, leaving more NT in the synaptic cleft
- "Antagonists" reduce signaling by competing for receptors, making them less available
- "Inverse agonists" bind to receptors but induce the opposite pharmacological effect
Fingers, toes, and arms are made according to ________ recipes in individual humans, even if the HERITABILITY in groups of humans is _______. HERITABILITY is _____ as GENETICS, even if everyone—even experts and teachers—often talks about it in that way.
- Genetic
- 0 or undefined
- Not the same as
If a very large GWAS, incorporating >100,000 subjects were to identify a SNP that predicts a small but significant % of variance in a trait or phenotype (e.g. N/NE, cholesterol, height, blood pressure), that means (A) It may be worth testing in an animal model (e.g. fruit flies, zebra fish, mice) because “% of variance” tells us nothing about mechanistic or causal importance (for example, when manipulated using a drug). (B) It’s definitely worthless because the trivial “% of variance” indicates it’s mechanistically or causally trivial
A
In rodents, (A) early-life handling does what to the pups' temperament? (B) What happens in the brain (name 1). (C) Is this a genetic or epigenetic effect, and how do we know that?
a. persistent life-long changes in temperament (less fearful, "tamer", healthier endocrine profile)
b. increased BDZ (GABAergic) receptor expression in amygdala, and glucocorticoid receptors in the hippocampus
c. epigenetic ... because cross-fostering ("adoption") studies show it's not due to genetics, and because it is associated with altered epigenetic marks