W14 - Depression 1/2 Flashcards
True of false: depression is a highly heterogenous disorder?
True.
What is resting state functional connectivity (rsFC)?
fMRI BOLD signal at rest.
What rsFC signature is consistently repeated across depressed individuals?
DMN hyperconnectivity
What are genomic wide association studies (GWAS) useful for?
Identifies genes at “risk” for a certain disorder across a very large number of individuals by looking into statistical associations between small changes in the genetic code
What could be two ways to identify depression-related genes?
GWAS
Post-mortem genetic expression levels (RNA-seq)
Where are localized the effects of depression on DMN connectivity according to Talishinsky et al.?
Anterior cingulate, dorsomedial PFC, lateral PFC, and insula
Where are localized the different changes in depressed males & females regarding abnormal connectivity?
Medial prefrontal cortex and temporal pole
What sexually dimorphic observation did Talishinsky et al. make about the hyperconnectivity in the DMN for depressed individuals?
Applies only to men
In women with depression, rsFC was mostly _____ in areas where males showed increases
In women with depression, rsFC was mostly decreased in areas where males showed increases
True or false: healthy males and females have the same DMN functional connectivity at baseline.
False: increased connectivity for females -> has to be kept in mind when comparing effects of depression on both sexes!
In clinical psychiatric research, sex should be a variable, not a _____.
covariate
What can be done to verify whether genes associated with depression (RNA-seq post-mortem) are related to sex differences in rsFC for depressed individuals?
Map gene expression onto the functional connectivity maps in order to identify genes that show strong regional differences in expression between regions showing altered rsFC
Did Talishinsky et al. find sex differences in the genes that are associated in changes in rsFC in depression?
Yes.
What 3 criteria did Talishinsky et al. use for identifying genes that might explain rsFC sex differences?
Normative expression strongly correlates with patterns of altered sex-specific rsFC
Transcriptionally altered in post-mortem brains of depressed individuals
Implicated in depression GWAS
What is the main finding of Talishinsky et al. regarding expression modules in depression that are sex-specific?
Genetic risk variants associated with depression contribute to the sex-specific changes in rsFC in the DMN and other depression-related circuits
