Final answer:
Antidepressants and antipsychotics are the drugs discussed as dopamine receptor antagonists and presynaptic alpha 2 adrenergic agonists, respectively.
Step-by-step explanation:
The types of drugs discussed in the context of dopamine receptor antagonists and presynaptic alpha 2 adrenergic agonists are antidepressants and antipsychotics. These drugs work by altering neurotransmitter activity in the brain to correct imbalances. Dopamine receptor antagonists are typically used as antipsychotics to treat disorders such as schizophrenia by blocking the effects of dopamine. Presynaptic alpha 2 adrenergic agonists are often used as antidepressants, as they enhance the effects of norepinephrine and epinephrine by inhibiting their release, which can improve mood and reduce symptoms of depression.