Questions & explanations
1. Compare and contrast the developmental pathways for internalizing (e.g., depression) and externalizing (e.g., conduct disorder) problems in childhood.
Internalizing problems involve emotional distress turned inward, like sadness and anxiety. A typical pathway starts with fearful temperament, overprotective parenting, and later social withdrawal. Externalizing problems involve acting out, like aggression and rule-breaking. Their pathway often begins with difficult temperament, harsh parenting, and peer deviance. Both pathways share genetic and environmental risks, but they diverge in how the child copes. Some children show both (comorbidity). Early intervention for externalizing (e.g., parent training) can also reduce later internalizing. But the timing and focus differ: externalizing interventions often target behavior, while internalizing ones target emotions.
2. What is stigma in the context of psychotic disorders?
Stigma means a set of negative and wrong beliefs that society holds about people with psychotic disorders like schizophrenia. Public stigma is when many people share these negative attitudes, such as thinking that those with psychosis are dangerous. Self-stigma happens when the person with the disorder accepts these wrong ideas and feels shame. Structural discrimination refers to laws or policies that unfairly limit opportunities for people with mental illness. For example, denying them jobs or housing because of their diagnosis. These can cause isolation, low self-esteem, and worse outcomes. Anti-stigma strategies include education and contact with people who have recovered.
3. What is the difference between candidate gene studies and genome-wide association studies (GWAS) in mental health research?
Candidate gene studies test one or a few genes thought to be involved in a disorder, based on prior knowledge. They often look at genes for neurotransmitters like dopamine or serotonin. GWAS instead scan the entire genome for tiny DNA changes (single nucleotide polymorphisms, or SNPs) that are more common in people with the disorder. GWAS do not start with a hypothesis about which gene matters. GWAS have found many small genetic contributions for disorders like schizophrenia and bipolar disorder. Together, these studies show that most mental disorders involve many genes, each with a tiny effect. Candidate gene studies are less reliable because they can give false positives.
4. How does the ICD-11 dimensional model address comorbidity between personality disorders and other mental disorders?
ICD-11 allows a person to have both a personality disorder diagnosis (with severity) and other mental disorders like depression or anxiety. The personality disorder is seen as a long-standing pattern, while other disorders are more episodic. The dimensional model reduces over-diagnosis of multiple personality disorder types, but comorbidity with axis I disorders is still common. The trait qualifiers can help identify personality traits that may influence treatment of other disorders. For example, high Negative Affectivity might make depression worse. The focus on severity helps clinicians prioritize treatment: severe personality disorder often needs to be addressed first.
5. Give an example of an age-specific manifestation of a disorder, such as how depression appears differently in children versus adults.
In adults, depression often involves sadness, loss of interest, and thoughts of worthlessness. In children, depression may look like irritability, temper tantrums, or physical complaints like stomachaches. Adolescents with depression might show social withdrawal, low energy, or risky behavior. Older adults may report memory problems or vague physical pain rather than sadness. These age-specific presentations happen because developmental stage affects how distress is expressed. So a child's irritability might be missed as depression. Clinicians use age-appropriate criteria to diagnose. This shows the developmental psychopathology principle that symptoms change with age.
6. How might the concept of 'evolutionary novelty' explain the rise of certain disorders like eating disorders?
Evolutionary novelty means that our bodies and brains are not well adapted to completely new environments. For anorexia nervosa, some researchers suggest that food restriction was an adaptive response to famine—it made people energetic and mobile to find new food sources. But in a modern society with abundant, low-nutrient food and thin-ideal media, the same drive can become pathological. The mismatch is between ancient thrifty metabolism and modern calorie-dense food plus social pressure. This is not a full explanation, but it helps understand why some people are vulnerable. It also suggests that preventing eating disorders may involve changing the modern environment.
7. Compare the DSM-5 categorical and ICD-11 dimensional models in terms of handling comorbidity.
In DSM-5 categorical, a person often gets multiple personality disorder diagnoses because the criteria are not exclusive. For example, a person can meet criteria for both borderline and histrionic. This makes it seem like they have several separate disorders, but research suggests these are overlapping problems. ICD-11 dimensional model handles comorbidity by giving a single personality disorder diagnosis with a severity rating and multiple trait qualifiers. So the same person might be described as having a moderate personality disorder with Negative Affectivity and Disinhibition. This reduces the number of diagnoses and better reflects the person's overall pattern.
8. Compare brain volume changes in obsessive-compulsive disorder (OCD) and anxiety disorders.
In OCD, meta-analyses often show reduced volume in the orbitofrontal cortex and anterior cingulate cortex, areas involved in decision-making and error detection. The caudate nucleus, part of the basal ganglia, may also be smaller. In anxiety disorders like generalized anxiety or panic disorder, volume reductions are more common in the amygdala and prefrontal cortex, but findings are less consistent. The amygdala, involved in fear, may be smaller in some anxiety disorders. Both OCD and anxiety disorders show some overlap, but OCD has more consistent changes in fronto-striatal circuits. These structural differences align with the different symptoms of each disorder.
9. Compare the AMPD and ICD-11 models for personality disorders.
Both AMPD and ICD-11 use a dimensional approach with a severity component and trait domains. AMPD has Criterion A (impairment in self and interpersonal functioning) and Criterion B (five pathological trait domains). ICD-11 has a single severity rating (mild, moderate, severe) and five optional trait qualifiers (Negative Affectivity, Detachment, Dissociality, Disinhibition, Anankastia). AMPD includes Psychoticism as a trait domain, while ICD-11 does not. AMPD also provides specific types for six classic disorders, whereas ICD-11 removes categorical types entirely. Both models aim to be more flexible and evidence-based than the traditional categorical approach.
10. Compare attentional bias in anxiety disorders versus attentional bias in depression.
In anxiety, attentional bias is usually toward threat (e.g., angry faces, spiders). This happens early, within milliseconds, and is linked to danger detection. In depression, attentional bias is more toward sad information and away from positive information. Depressed people may also have difficulty disengaging from negative stimuli. Anxious people are often hypervigilant (scanning for threat), while depressed people may show reduced attention to reward cues. The biases differ in timing: anxiety bias is faster, while depression bias involves slower, sustained attention. Both biases maintain their respective disorders but target different emotional material.
11. Compare the genetic overlap between different mental disorders and what that tells us about their causes.
Large genetic studies show that many mental disorders share genetic risk factors. For example, schizophrenia and bipolar disorder have moderate genetic overlap. Major depression and anxiety disorders also share some genetic influences. This suggests that some genes affect general mental health, not just one disorder. However, each disorder also has unique genetic factors. This overlap explains why disorders often occur together (comorbidity) in the same person or family. It also supports a dimensional view of psychopathology rather than completely separate categories. Understanding shared genetics can lead to treatments that work across multiple disorders.
12. Explain the mismatch hypothesis using the example of depression.
The mismatch hypothesis says that adaptations which helped our ancestors may be harmful in today's environment. For depression, some scientists think that low mood and withdrawal were useful in ancestral times for conserving energy when a goal was impossible. In a modern world full of social media and constant deadlines, this response can be triggered too often. For example, repeated social rejection on social media might trigger a depressive episode, even though it's not life-threatening. The mismatch is between our ancient social brain and modern digital social life. This perspective suggests that changing the environment or how we interpret it may help.