Which dopaminergic pathway is most associated with movement and extrapyramidal symptoms when disrupted?

Which dopaminergic pathway is most associated with movement and extrapyramidal symptoms when disrupted?

• A. Nigrostriatal pathway
• B. Mesolimbic pathway
• C. Mesocortical pathway
• D. Tuberoinfundibular pathway

Answer: (A)

Movement control and extrapyramidal symptoms are primarily linked to the nigrostriatal dopaminergic pathway. This tract runs from the substantia nigra to the striatum (caudate and putamen) and finely tunes motor activity. When dopamine signaling in this pathway is reduced or disrupted, as seen in Parkinson disease or when D2 receptors in this pathway are blocked by antipsychotics, it leads to movement-related problems such as tremor, rigidity, and slowed movement—hallmarks of extrapyramidal symptoms. In contrast, the mesolimbic pathway is involved mainly in reward and reinforcement and is tied to positive psychotic symptoms when overactive. The mesocortical pathway influences cognition and mood, with disruptions contributing to cognitive and negative symptoms. The tuberoinfundibular pathway regulates prolactin release from the pituitary; disturbances here affect endocrine function rather than movement. Hence, the pathway most associated with movement and extrapyramidal symptoms is the nigrostriatal pathway.

Movement control and extrapyramidal symptoms are primarily linked to the nigrostriatal dopaminergic pathway. This tract runs from the substantia nigra to the striatum (caudate and putamen) and finely tunes motor activity. When dopamine signaling in this pathway is reduced or disrupted, as seen in Parkinson disease or when D2 receptors in this pathway are blocked by antipsychotics, it leads to movement-related problems such as tremor, rigidity, and slowed movement—hallmarks of extrapyramidal symptoms.

In contrast, the mesolimbic pathway is involved mainly in reward and reinforcement and is tied to positive psychotic symptoms when overactive. The mesocortical pathway influences cognition and mood, with disruptions contributing to cognitive and negative symptoms. The tuberoinfundibular pathway regulates prolactin release from the pituitary; disturbances here affect endocrine function rather than movement. Hence, the pathway most associated with movement and extrapyramidal symptoms is the nigrostriatal pathway.