Genes and Biological models

What did FJ Gall believe about phrenology?

That there was a 1-1 link between a brain region and function

Why do some people argue that brain imaging studies are “modern” phrenology?

Because there’s a very high rise in brain imaging studies, trying to connect brain regions to specific functions

Neurotransmitters are proteins in the brain, of which there are three basic systems. What are they called and which is important for MAPD?

Amino acids, Mono-amines and peptides

Mono-amines (Serotonin, Dopamine & Adrenaline) are important for MAPD

What does the “emotion” network of the brain consist of?

•Amygdala \n •Conditioning, face processing \n •Serotonin \n •Norepinephrine

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This network is also related a lot to other regions (for example, the cognitive control one)

What does the “motivation” network of the brain consist of?

•Striatum \n •Motivation, Pleasure \n •Dopamine

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It’s there for processing motivation and related to goal-directed activity and obtaining a reward

What does the “cognitive control” network of the brain consist of?

•Prefrontal cortex \n •Working memory, emotion regulation \n

There for regulating emotions and motivational systems. In mental disorders, there’s often something off with the balance of the regulation (often lack of regulation in anxiety or mood disorders)

What does the “default mode” network of the brain consist of?

•PCC & vmPFC \n •Introspection

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Also rumination, which is overly present in people w depression

What did the study where people had to anticipate making a speech show?

They had higher heart rate and more stress, but in the control group, cognitive control kicked in whereas in the SAD group, cognitive control part barely communicated with the emotion part -- the emotion part takes over

Why is there an issue with statistical power in FMRI studies?

The sample sizes are very low (around 20-30), but the brain areas they’re studying are about 200,000, meaning there’s about 200,000 variables

Furthermore, you need a lot of subjects if the relationship between the brain regions and constructs is diffused and weak

How are MAPD represented in specific brain areas?

There are many more brain regions related to multiple terms than just one specific one

How do antidepressants work?

They affect the levels of serotonin, adrenaline and dopamine in the brain

Why is there the theory that depression is a disorder of the neurotransmitter systems?

Because antidepressants affect the neurotransmitter system. However, this is like saying headaches are caused by a lack of aspirin

How effective are antidepressants?

Not very effective if compared to placebo (Cohen’s D= 0.3), but the total effect (not compared to placebo) is quite high (0.8-1.4)

What are the placebo responses composed of?

* Effect of clinical management
* Expectations
* Natural course
* Regression to the mean

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What might be the future of placebo pills?

Open-labelled placebo has also been shown to work to some degree, but placebo in general is not as effective as psychotherapy

Why has it taken so long to realise the caveats of antidepressants?

* Publication bias
* Outcome reporting bias: results are initially negative, then positive (distorted reporting)
* Spin: negative results are interpreted positively

Candidate gene studies

Gene studies where you find a link between a specific gene and a mental illness and then test that gene

Fill in what goes where in the Venn diagram