Antidepressants and Their Mechanisms

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Questions and Answers

What is the primary mechanism of action for tricyclic antidepressants?

Inhibit the reuptake of serotonin only

Activating serotonin receptors

Increasing the production of dopamine

Block transporter proteins for serotonin, dopamine, and norepinephrine (correct)

Which side effect is commonly associated with the blockage of acetylcholine receptors by tricyclic antidepressants?

Dry mouth (correct)

Increased heart rate

Drowsiness

Heightened anxiety

How do selective serotonin reuptake inhibitors (SSRIs) work?

Block norepinephrine receptors

Lock the serotonin transporter into a shape that prevents serotonin binding (correct)

Inhibit the presynaptic release of serotonin

Increase the activity of monoamine oxidase

Which class of antidepressants is known for blocking monoamine oxidase?

MAOIs Signup and view all the answers

What neurotransmitters do serotonin norepinephrine reuptake inhibitors (SNRIs) affect?

Both serotonin and norepinephrine Signup and view all the answers

What is a significant concern associated with using St. John’s wort as an antidepressant?

It decreases the effectiveness of other medications. Signup and view all the answers

Which neurotrophin is associated with depression and plays a critical role in synaptic plasticity?

Brain-derived neurotrophic factor (BDNF) Signup and view all the answers

What is one limitation of standard antidepressants regarding their effectiveness?

They must accumulate over time to show significant effects. Signup and view all the answers

What findings have studies generally reported about the efficacy of antidepressants compared to placebos?

Antidepressants show moderate effectiveness over placebos. Signup and view all the answers

How do psychedelics like LSD or psilocybin help in treating depression?

They enhance neural plasticity, allowing for new thought patterns. Signup and view all the answers

Why must psychedelics be administered in a therapeutic session?

To prevent the potential for misuse and manage dangers. Signup and view all the answers

What is one way in which ketamine reduces depression?

By facilitating the BDNF receptor and synaptic plasticity. Signup and view all the answers

Which of the following is true regarding the doses of SSRIs and their effects?

There is little evidence that different doses produce different effects. Signup and view all the answers

Which factor is NOT associated with an increased risk of developing schizophrenia?

Consuming a balanced diet in childhood Signup and view all the answers

What genetic factor is identified as playing a significant role in the risk of developing schizophrenia?

Microdeletion on a chromosome Signup and view all the answers

What does the two-hit hypothesis suggest about the development of schizophrenia?

It is due to a combination of genetic predisposition and environmental impacts. Signup and view all the answers

Which type of twins shows a higher concordance rate for schizophrenia?

Monozygotic twins Signup and view all the answers

What is the season-of-birth effect concerning schizophrenia?

Individuals born in winter have a slightly higher probability of developing schizophrenia. Signup and view all the answers

Which gene is commonly related to schizophrenia and affects neuron differentiation and migration?

DISC1 Signup and view all the answers

Which of the following is a non-genetic factor that can influence the development of schizophrenia?

Prenatal exposure to stress Signup and view all the answers

What major histocompatibility complex alteration is associated with schizophrenia?

Disruption of immune system recognition Signup and view all the answers

Which prenatal factor does NOT contribute to an increased risk of schizophrenia?

Living in a high-altitude area Signup and view all the answers

Which statement about genetic influences on schizophrenia is true?

Monozygotic twins have a concordance rate of about 50%. Signup and view all the answers

What role does dopamine play in substance use and abuse?

It increases motivation to seek substances. Signup and view all the answers

How do agonists function in relation to neurotransmitters?

They mimic or increase the effects of neurotransmitters. Signup and view all the answers

What is meant by drug tolerance?

A learned decrease in drug effects over time. Signup and view all the answers

What is the main impact of withdrawal from a drug?

It causes increased cravings for more of the drug. Signup and view all the answers

What characterizes a mixed agonist-antagonist drug?

It either mimics or blocks neurotransmitter effects depending on the dose. Signup and view all the answers

Which outcome is often seen in individuals with early-onset alcoholism?

They typically exhibit genetic predispositions towards alcoholism. Signup and view all the answers

What is the function of disulfiram (Antabuse) in alcohol abuse treatment?

It antagonizes the enzyme that metabolizes acetaldehyde. Signup and view all the answers

What may happen to dopamine levels in individuals after prolonged drug use?

Dopamine release from the drug may decrease over time. Signup and view all the answers

What distinguishes 'liking' from 'wanting' in psychological terms?

Liking is associated with pleasure, while wanting relates to motivation. Signup and view all the answers

What is a potential consequence of cues associated with drug use after addiction?

They can trigger cravings and increased dopamine release. Signup and view all the answers

Which of the following behaviors might indicate a future risk of alcoholism?

Less than average intoxication after drinking a moderate amount. Signup and view all the answers

What role does parental supervision have in the predisposition to substance abuse?

More supervision decreases the likelihood of impulse control issues. Signup and view all the answers

How do environmental factors contribute to substance abuse susceptibility?

Environmental stressors can increase vulnerability to addiction. Signup and view all the answers

What is a likely consequence of living in a crowded urban environment in relation to schizophrenia?

Higher levels of air pollution Signup and view all the answers

Which drug is known for relieving the positive symptoms of schizophrenia?

Haloperidol Signup and view all the answers

What brain area is frequently found to be impaired in individuals with schizophrenia?

Pre-frontal cortex Signup and view all the answers

What could potentially contribute to the increased release of glutamate in individuals with schizophrenia?

Reduced NMDA receptor activity Signup and view all the answers

Which generation of antipsychotic drugs is associated with a lower risk of movement disorders?

Second-generation antipsychotics Signup and view all the answers

What symptom is commonly observed in individuals with autism spectrum disorders?

Empathy deficits Signup and view all the answers

What environmental factor is linked to an increased risk of autism during pregnancy?

Exposure to air pollutants Signup and view all the answers

What is one of the side effects associated with traditional antipsychotic medications?

Tardive dyskinesia Signup and view all the answers

How do newer antipsychotic drugs primarily relieve symptoms of schizophrenia?

By modulating dopamine transmission Signup and view all the answers

What characteristic is common amongst individuals on the autism spectrum?

Repetitive movements Signup and view all the answers

What type of drug is chlorpromazine classified as?

First-generation antipsychotic Signup and view all the answers

What role does folic acid have in relation to autism risk during pregnancy?

Reduces the risk of autism Signup and view all the answers

What is the dopamine hypothesis of schizophrenia primarily concerned with?

Excess dopamine activity at synapses Signup and view all the answers

What effect does ketamine have on NMDA-type receptors?

Blocks them in the lateral habenula. Signup and view all the answers

Which treatment is known for having no side effects and longer-lasting effects compared to antidepressant drugs?

Psychotherapy. Signup and view all the answers

What is a primary disadvantage of psychotherapy as a treatment for depression?

It requires regular visits to a therapist's office. Signup and view all the answers

What is a common advantage of electroconvulsive therapy (ECT)?

It acts faster than standard antidepressants. Signup and view all the answers

Which condition is characterized by alternating episodes of depression and mania?

Bipolar disorder. Signup and view all the answers

How do lithium salts function in the treatment of bipolar disorder?

They prevent a relapse into both mania and depression. Signup and view all the answers

To be diagnosed with schizophrenia, which is a necessary criterion?

Deterioration in everyday functioning must be evident for at least 6 months. Signup and view all the answers

Which of the following is classified as a positive symptom of schizophrenia?

Delusions. Signup and view all the answers

What is a common cognitive impairment in individuals with schizophrenia?

Difficulty in facial emotion perception. Signup and view all the answers

Which alternative treatment to medication is recognized for its equal benefits to antidepressants?

Cognitive behavioral therapy. Signup and view all the answers

Seasonal affective disorder (SAD) is most prevalent in which geographic areas?

Near the poles, especially in winter. Signup and view all the answers

What characteristic behavior is often associated with mania in bipolar disorder?

Excessive self-confidence. Signup and view all the answers

What unique physical characteristic is observed in many individuals with schizophrenia?

Characteristic body odor. Signup and view all the answers

Study Notes

Psychopathology - Module 14.1 Substance Abuse

Drugs can either facilitate or inhibit transmission at synapses.
Antagonist: A drug that blocks a neurotransmitter. It causes neurotransmitter vesicles to leak or blocks postsynaptic receptors.
Agonist: A drug that mimics or increases the effects of a neurotransmitter. It increases neurotransmitter release or decreases neurotransmitter reuptake or blocks breakdown of neurotransmitter.
A mixed agonist-antagonist acts as an agonist for some effects and an antagonist for others.
A drug's affinity describes its tendency to bind to a receptor (like a key to a lock).
A drug's efficacy describes its tendency to activate the receptor.
Dopamine release is crucial for reinforcing behaviors.

Drug Effects and Tolerance

Stimulant drugs (cocaine, amphetamine) increase or prolong dopamine release in the nucleus accumbens.
Nicotine stimulates dopamine release.
Opiates decrease dopamine release.
Dopamine is important for wanting something, not necessarily for enjoying it.
Cravings are an insistent search for the drug.
Repeated drug use decreases blood flow and metabolism in the prefrontal cortex, leading to reduced impulse control.
Tolerance: A decrease in the drug's effect as addiction develops, often learned.
Tolerance can be weakened through extinction.
Withdrawal: The body's strong reaction when the drug is absent.
Drug use is sometimes used as a coping mechanism for stress.

Genetic Influences and Predisposition to Substance Abuse

Family history of alcoholism correlates more strongly with biological children than adopted children.
A gene affecting alcohol metabolism can influence alcohol abuse risk.
People metabolizing acetaldehyde slowly may experience adverse effects from alcohol consumption (flushing, increased heart rate, nausea, headache, abdominal pain, impaired breathing, and tissue damage).
Experiences in childhood, including abuse and lack of parental supervision, increase vulnerability to substance abuse problems.
Early-onset alcoholism is more likely to have a family history and to have rapid onset of the problem, compared to later-onset cases where reactions to life difficulties are more impacting.

Treatments for Substance Abuse

Antabuse: An antagonist for acetaldehyde dehydrogenase, making alcohol consumption unpleasant. Its effectiveness is similar to a placebo.
Medications like methadone, buprenorphine, and LAAM are used to treat opiate addiction, offering a less dangerous way to satisfy cravings.
Medications help replace cravings, withdrawal symptoms, and the need to use substances for coping.

Mood Disorders - Module 14.2

Major Depressive Disorder: Characterized by persistent sadness, helplessness, reduced reward response, and impaired memory, attention, and happiness.
Treatments: Antidepressants (tricyclics, SSRIs, SNRIs, MAOIs, atypical) and psychotherapy.
Electroconvulsive Therapy (ECT): Treatment using electrical stimulation, effective for some drug-resistant cases.

Schizophrenia - Module 14.3

Schizophrenia is a disease with split between emotional and intellectual aspects, occurring in adulthood. Symptoms can begin in childhood with problems in memory, attention, and impulse control.
Symptoms include delusions, hallucinations, disorganized speech, disorganized behavior, and weak emotional expression/socialization.
Positive symptoms represent behaviors that are usually absent (hallucinations, delusions), whereas negative symptoms reflect behaviors that are typically present (emotional expression, socialization).
Treatments: Antipsychotic medications (chlorpromazine, butyrophenones, etc.) affect dopamine pathways in the brain to reduce symptoms.
Two-hit hypothesis: A combination of genetic predisposition and environmental factors (during prenatal/early postnatal development) create the conditions for schizophrenia.

Autism Spectrum Disorders (Module 14.4)

Autism is characterized by deficits in social and emotional exchange, communication, stereotyped behaviors and resistance to changes in routine. Some individuals may have normal or above-average intellect.
Some cases of autism are traced to a single gene, but in many cases several factors may contribute to the development of autism. Exposure to environmental toxins, such as pesticides and large amounts of pollutants during pregnancy, and conditions like epilepsy and anxiety may increase the risk.
Treatments: Behavioral therapy is usually the most effective treatment as it works on communication, social skills, and other autism-related deficits. Often involves family members.

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Description

Test your knowledge on the mechanisms of action and side effects of various antidepressants. This quiz covers tricyclic antidepressants, selective serotonin reuptake inhibitors, and other classes of antidepressants. Boost your understanding of how these medications affect neurotransmitters.