Mesolimbic pathway

• Controls the motivation and reward systems of the brain (e.g., pleasure, positive reinforcement)
• Stimulation causes positive symptoms (e.g., hallucinations)
• Primary target for antipsychotic drugs used in the treatment of schizophrenia (e.g., haloperidol)

Mnemonic

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Tuberoinfundibular pathway

• Dopamine release inhibits prolactin secretion from the anterior pituitary.
• Inhibition causes ↓ dopamine → ↑ prolactin → galactorrhea, sexual dysfunction, ↓ libido
• Antipsychotic drugs significantly affect this pathway.

Mnemonic

Tubero Infundibular Pathway = This Inhibits Prolactin

Nigrostriatal pathway

• Controls motor function
• Altered activity causes extrapyramidal symptoms and movement disorders (parkinsonism in the case of inhibition, chorea in the case of stimulation).

Mnemonic

Nigro Striatal Pathway = iNvoluntary movements, Stuttering, and Parkinsonism

Mesocortical pathway

• Controls executive functions, motivation, and reward systems of the brain
• Inhibition causes negative symptoms (e.g., apathy, lack of energy).
• Antipsychotic drugs have limited efficacy.

Mnemonic

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