Final answer:
Excess dopamine in the striatum can lead to psychosis, while insufficient dopamine in the PFC often results in cognitive issues. In Parkinson's Disease, L-DOPA treatment helps increase striatal dopamine, though careful management is needed to avoid side effects such as psychosis. Understanding neurotransmitter balance and excitotoxicity is essential for treatment.
Step-by-step explanation:
Excess dopamine in the striatum is associated with psychotic symptoms such as those seen in schizophrenia, whereas too little dopamine in the prefrontal cortex (PFC) can lead to cognitive deficits, such as impaired executive functions. In Parkinson's disease, the loss of dopaminergic neurons in the substantia nigra pars compacta leads to reduced dopamine levels in the striatum, causing motor symptoms such as tremors and rigidity. Treatment strategies often include the administration of L-DOPA, a dopamine precursor that can cross the blood-brain barrier, to increase striatal dopamine levels. However, challenges arise when trying to manage increased dopamine elsewhere in the brain, which can result in adverse effects like psychosis. Glutamate excitotoxicity and other changes in neurotransmitter balance also play significant roles in Parkinson's and can inform more targeted therapeutic approaches.