F. Psychological Disorders Flashcards
What is the Nucleus Accumbens (NAc)?
Located at the anterior end of the striatum in the forebrain, it serves as a key center for processing rewards, emotions, and addiction.
What are the key roles of the Nucleus Accumbens?
- Reward Processing: Activation during pleasurable experiences releases dopamine.
- Dopamine Release: Central to reinforcement learning.
- Motivation and Goal-Directed Behavior: Integrates cognitive and emotional cues.
- Anticipation of Rewards: Predicts the value of future rewards.
- Effort and Persistence Regulation: Balances perceived effort versus reward value.
What is the clinical relevance of the Nucleus Accumbens?
In addiction, the NAc is hypersensitive, contributing to compulsive behaviors. In depression, reduced dopamine leads to emotional numbness and lack of pleasure.
What are cravings in the context of addiction?
Intense urges for substances driven by brain anticipation of rewards, linked to biological changes in the reward system involving dopamine.
How does dopamine relate to cravings?
Substance use increases dopamine in reward pathways; repeated use leads to neuroadaptation, reducing natural dopamine responses.
What is classical conditioning in relation to cravings?
Environmental cues associated with substance use trigger cravings.
What is operant conditioning in relation to cravings?
Positive reinforcement from initial use and negative reinforcement from withdrawal symptoms reinforce cravings.
What role do the Amygdala and Hippocampus play in cravings?
These regions encode memories that trigger cravings when encountering reminders of past use.
What are some treatments for managing cravings?
- Cognitive Behavioral Therapy (CBT): Helps identify triggers.
- Medications: Methadone/suboxone stabilize dopamine levels.
- Lifestyle Interventions: Exercise and mindfulness.
- Support Systems: Group therapies increase accountability.
What is the genetic contribution to substance abuse?
Genetic factors account for 40-60% of addiction risk, with genes like DRD2 influencing dopamine receptor availability.
What is the heritability of depression?
Heritability is about 30-40%, with many genes involved, such as the serotonin transporter gene (SLC6A4).
What is the heritability of schizophrenia?
Highly heritable (80%), linked to genes affecting synaptic pruning and dopamine signaling.
What is the heritability of Autism Spectrum Disorder (ASD)?
Heritable (50-90%), involving common and rare gene mutations related to synaptic development.
What are prenatal influences on psychological disorders?
- Maternal Nutrition: Poor nutrition can impede fetal development.
- Alcohol Intake: Increases risk for developmental issues.
- Pollutant Exposure: Environmental toxins increase likelihood of disorders.
- Prenatal Infections: Linked to various psychological disorders.
- Mother-Child Compatibility: Genetic incompatibilities can lead to increased risks.
What are the symptoms and treatments for Major Depressive Disorder (MDD)?
Symptoms include persistent sadness and fatigue. Treated with antidepressants and CBT.
