Biological Therapies: Drug and Brain-Based Treatments in Psychology

Biological Therapies

Overview of Drug Therapies

Biological therapies in psychology focus on treating psychological disorders through medical interventions, primarily medications and brain-based procedures. These therapies target the biological underpinnings of mental illness, such as neurotransmitter imbalances and abnormal brain activity.

• Four main classes of drug therapies:

  • Antipsychotics: Used to treat schizophrenia and disorders that involve psychosis.

  • Antidepressants: Primarily treat depression, anxiety, and obsessive-compulsive disorder (OCD).

  • Anti-anxiety: Used for anxiety disorders; also called tranquilizers.

  • Mood stabilizers: Primarily treat bipolar disorder.

• Mechanism of Action: Drugs alter chemical interactions in the brain, producing effects that can help symptoms but may also cause side effects.

Antipsychotics

Antipsychotic medications are used to treat disorders involving psychosis, such as schizophrenia. They work by affecting neurotransmitter systems in the brain, particularly dopamine.

Type of Drug	Generation	Mechanism of Action	Specific Side Effects
Typical Antipsychotics	First	Block dopamine receptors	Muscle rigidity & involuntary movements
Atypical Antipsychotics	Second	Block dopamine & serotonin receptors	Effect: reduced movement side effects, weight gain

• Typical antipsychotics: More likely to cause movement-related side effects.

• Atypical antipsychotics: Target both dopamine and serotonin, with fewer movement side effects but possible weight gain.

Antidepressants

Antidepressants are used to treat depression, anxiety, and OCD. They work by altering levels of neurotransmitters such as serotonin and norepinephrine.

Type of Drug	Generation	Mechanism of Action	Specific Side Effects
Monoamine Oxidase Inhibitor (MAOI)	First	Prevents degradation of neurotransmitters	Weight gain
Tricyclics	First	Blocks reuptake of serotonin & norepinephrine	Emotional blunting, sedation
Selective Serotonin Reuptake Inhibitor (SSRI)	Second	Blocks reuptake of serotonin	Generally fewer side effects

• Reuptake: Process by which neurotransmitters are reabsorbed into the presynaptic neuron, reducing their activity in the synaptic gap.

• Degradation: Breakdown of neurotransmitters by enzymes.

Anti-Anxiety Medications

Anti-anxiety drugs, also known as tranquilizers, are used to treat anxiety disorders. They have a calming, tranquilizing effect and are generally prescribed for short-term use.

Type of Drug	Mechanism of Action	Specific Side Effects
Benzodiazepines	Increase activity of GABA (an inhibitory neurotransmitter)	Drowsiness, sedation, slowed respiration

• GABA: Gamma-aminobutyric acid, an inhibitory neurotransmitter that reduces neuronal excitability.

• Long-term use can lead to tolerance and dependence.

Mood Stabilizers

Mood stabilizers are used to treat bipolar disorder, helping to control both depressive and manic episodes.

Type of Drug	Mechanism of Action	Specific Side Effects
Lithium	Not fully understood	Weight gain, dysfunction (organ-related)
Anticonvulsants	May target GABA and glutamate	May be used if lithium is ineffective

• Lithium: Most common mood stabilizer; requires monitoring due to potential toxicity.

Review Table: Drug Classes

Class	Purpose	Mechanism of Action	Specific Side Effects
Antipsychotics (Typical)	Shorten episodes, reduce psychosis	Block dopamine receptors	Muscle rigidity, involuntary movements
Antipsychotics (Atypical)	Shorten episodes, reduce psychosis	Block dopamine & serotonin receptors	Weight gain, fewer movement side effects
Antidepressants (MAOI)	Elevate mood	Prevents degradation of neurotransmitters	Weight gain
Antidepressants (Tricyclics)	Elevate mood	Blocks reuptake of serotonin & norepinephrine	Emotional blunting, sedation
Antidepressants (SSRI)	Elevate mood	Blocks reuptake of serotonin	Fewer side effects
Anti-anxiety (Benzodiazepines)	Calming, tranquilizing	Increase GABA activity	Drowsiness, sedation, slowed respiration
Mood Stabilizers (Lithium)	Stabilize mood	Not fully understood	Weight gain, organ dysfunction

Considerations Regarding Drug Therapies

When prescribing medication, providers must consider non-medical treatments, side effects, and unknown risks. The placebo effect is a significant factor in treatment outcomes.

• Placebo Effect: Improvement due to expectation, not the active ingredient.

• Studies use placebos to compare efficacy of treatments.

• Medication can be part of a life-long changing and evolving plan.

Brain Surgery and Stimulation

Some severe cases of depression or other disorders may be treated with brain-based interventions, including stimulation and surgery.

Treatment	Indication	Procedure	Additional Info
Transcranial Magnetic Stimulation (TMS)	Severe depression	Magnetic field applied over the prefrontal cortex	Minimal side effects, non-invasive
Electroconvulsive Therapy (ECT)	Severe depression	Electric shock under anesthesia	Memory side effects, does not require anesthesia
Anterior Cingulotomy	Severe depression, OCD	Lesion created in the anterior cingulate cortex	Only about 50% of patients show improvement

• TMS: Non-invasive, uses magnetic fields to stimulate brain regions.

• ECT: Involves electrical stimulation; can cause memory loss.

• Anterior Cingulotomy: Surgical procedure for treatment-resistant cases.

Key Terms and Definitions

• Psychosis: Loss of contact with reality, often involving hallucinations or delusions.

• Depression: Persistent low mood and loss of interest in activities.

• Anxiety: Excessive worry or fear.

• Bipolar Disorder: Mood disorder with alternating periods of depression and mania.

• Neurotransmitter: Chemical messenger in the brain.

Example Applications

• Antipsychotics: Prescribed for schizophrenia, may cause movement side effects.

• Antidepressants: SSRIs are commonly used for depression and anxiety, with fewer side effects than older drugs.

• Anti-anxiety: Benzodiazepines are effective for short-term anxiety but can lead to dependence.

• Mood stabilizers: Lithium is standard for bipolar disorder, but requires monitoring.

• Brain stimulation: TMS and ECT are options for treatment-resistant depression.

Formulas and Equations

• Reuptake inhibition: $\text{Neurotransmitter}_{\text{synaptic gap}} = \text{Released} - \text{Reuptake}$

• Placebo effect (conceptual): $\text{Improvement}_{\text{placebo}} = \text{Expectation}_{\text{patient}}$

Additional info: Some content inferred for completeness, such as definitions and expanded explanations of drug mechanisms and side effects.