Pathological feature characteristic of Parkinson’s disease is?
**Core Concept**
Parkinson's disease is a neurodegenerative disorder characterized by the progressive loss of dopamine-producing neurons in the substantia nigra, a region of the brain that plays a crucial role in motor control. This neuronal degeneration leads to a significant reduction in dopamine levels, resulting in the hallmark symptoms of the disease.
**Why the Correct Answer is Right**
The correct answer is related to the pathological feature of Parkinson's disease, which is the presence of **Lewy bodies** within the neurons of the substantia nigra. Lewy bodies are abnormal protein clumps composed of alpha-synuclein that accumulate in the neurons, leading to their degeneration and death. This process disrupts the normal functioning of the brain's motor control systems, resulting in the characteristic symptoms of Parkinson's disease, including tremors, rigidity, and bradykinesia.
**Why Each Wrong Option is Incorrect**
**Option A:** **Neuronal loss in the hippocampus** is a feature of Alzheimer's disease, not Parkinson's disease.
**Option B:** **Motor neuron degeneration** is characteristic of amyotrophic lateral sclerosis (ALS), not Parkinson's disease.
**Option C:** **White matter lesions** are often seen in multiple sclerosis, not Parkinson's disease.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that Lewy bodies are a hallmark pathological feature of Parkinson's disease, and their presence can be used to support the diagnosis in a patient with characteristic symptoms.
**Correct Answer: C. Lewy bodies.