NEET-PG 2015 Practice Questions

Q: Most common site of hypertensive intraparenchymal hemorrhage in the brain?

Putamen. ***Putamen*** - The **putamen** is the most frequent site for **hypertensive intraparenchymal hemorrhages** [1] due to the presence of numerous small, thin-walled arterioles (lenticulostriate arteries) that are highly susceptible to damage from chronic hypertension [1]. - Hemorrhages in this region often cause **contralateral hemiparesis**, **hemianesthesia**, and **gaze deviation** towards the side of the lesion due to involvement of nearby motor and sensory pathways [1]. *Thalamus* - While the **thalamus** is a common site for hypertensive hemorrhages, it is less common than the putamen [1], [2]. - Thalamic hemorrhages typically cause **contralateral sensory loss**, **oculomotor dysfunction**, and sometimes **aphasia** if the dominant hemisphere is affected. *Cerebellum* - **Cerebellar hemorrhages** are less frequent than those in the basal ganglia or thalamus [1]. - Symptoms usually include **ataxia**, **nystagmus**, vomiting, and potential brainstem compression if large. *Pons* - **Pontine hemorrhages** are among the most severe and are often rapidly fatal due to damage to vital brainstem structures [1], [2]. - They typically present with **coma**, **quadriparesis**, **pinpoint pupils**, and rapid progression to respiratory arrest.

Q: Which of the following sites is responsible for the amnestic defect in Wernicke's Korsakoff syndrome:

Thalamus. ***Thalamus*** - Damage to the **medial dorsal nucleus of the thalamus** is a key pathological finding in Wernicke's Korsakoff syndrome, directly contributing to the severe **anterograde and retrograde amnesia** [1]. - The thalamus plays a crucial role in memory consolidation and retrieval, acting as a relay station for information processing between cortical and subcortical structures. *Mammillary body* - While **mammillary body damage** is characteristic of Wernicke-Korsakoff syndrome, it is primarily associated with the **acute Wernicke encephalopathy phase** and contributes to the overall amnesia through its connections with the thalamus and hippocampus, rather than being the sole site for the amnestic defect [1]. - The mammillary bodies are part of the **Papez circuit**, which is important for episodic memory, but their lesion alone doesn't fully explain the complete amnestic syndrome. *Hippocampus* - The **hippocampus** is critical for the formation of new memories, and its damage typically causes **anterograde amnesia**, as seen in conditions like temporal lobe epilepsy or anoxia. - While memory is affected, direct **hippocampal lesions are not the primary pathology** in Wernicke-Korsakoff syndrome; the memory impairment arises from damage to structures *connected* to the hippocampus, such as the thalamus and mammillary bodies. *Periventricular Grey matter* - The **periventricular grey matter** is involved in various autonomic functions and pain modulation, not directly in memory formation or retrieval. - While lesions in this area can occur in Wernicke-Korsakoff syndrome, they are not considered the primary cause of the **amnestic defect**.

Q: Which of the following is the most common initial presenting feature of multiple sclerosis:

Optic Neuritis. ***Optic Neuritis*** - **Optic neuritis** is a very common initial symptom of multiple sclerosis, occurring in 20-25% of patients. - It presents with **unilateral vision loss** (often painful), blurred vision, and a central scotoma, reflecting inflammation and demyelination of the optic nerve [1]. *Cerebellar Ataxia* - While **cerebellar ataxia** (impaired coordination, balance, speech) can occur in MS, it is less common as an initial presenting symptom. - It often develops later in the disease course due to demyelination in the **cerebellum** or its connections [1]. *Internuclear ophthalmoplegia* - **Internuclear ophthalmoplegia (INO)** is a specific eye movement disorder common in MS but rarely the very first symptom [1]. - It results from a lesion in the **medial longitudinal fasciculus (MLF)**, causing impaired adduction of one eye during conjugate gaze with nystagmus in the abducting eye. *Diplopia* - **Diplopia** (double vision) can be an early symptom of MS, but it is less frequent as the very first presentation compared to optic neuritis [1]. - It typically arises from lesions affecting the **cranial nerves** controlling eye movements (III, IV, VI) or their brainstem nuclei.

Q: What are the expected neurological manifestations in a patient with complete absence of the corpus callosum?

Severe developmental delays. ***Severe developmental delays*** - Complete agenesis of the corpus callosum often results in **significant neurological impairments** due to the disruption of interhemispheric communication essential for coordinated brain function. - This typically manifests as **intellectual disability**, **developmental delays** in motor and speech skills, and difficulties with complex cognitive tasks. *Mild cognitive impairment* - While some individuals with partial agenesis or isolated cases might present with mild cognitive issues, **complete absence** usually leads to more profound deficits. - Mild impairment would not fully capture the extensive neurological challenges associated with a total lack of such a critical brain structure. *Seizures* - Seizures can occur in patients with corpus callosum agenesis, but they are not the **most encompassing** or universally expected neurological manifestation. - Seizures are often part of a broader syndrome of developmental abnormalities rather than the primary expected outcome of the agenesis itself. *No significant neurological deficits* - The corpus callosum is vital for **integrating information** between the cerebral hemispheres, affecting a wide range of sensory, motor, and cognitive functions. - Therefore, its complete absence almost invariably leads to notable neurological deficits, making a lack of significant issues highly unlikely.

Q: What is the first symptom of Parkinson's disease?

Tremors. ***Tremors*** - A resting **tremor**, often starting unilaterally in a hand or foot, is frequently the **initial motor symptom** of Parkinson's disease [1]. - This tremor is typically **slow**, rhythmic, and may involve a "pill-rolling" motion of the fingers [1]. *Postural instability* - **Postural instability** tends to be a later symptom, emerging as the disease progresses and affecting balance and gait [2]. - It is not usually the **presenting complaint** in the early stages of Parkinson's disease [2]. *Rigidity* - **Rigidity**, characterized by increased muscle tone and resistance to passive movement, often develops after tremors or bradykinesia [1]. - It can manifest as **cogwheel** or **lead-pipe rigidity** and contributes to the stooped posture and reduced arm swing observed in Parkinson's patients [1]. *Bradykinesia* - **Bradykinesia** (slowness of movement) is a core motor symptom, often described as difficulty initiating or continuing movements [1]. - While present early, **tremors** are often the first symptom noticed by the patient or their family, making bradykinesia a close second in sequence [1].

Q: Isaac syndrome is characterized by -

Peripheral nerve hyperexcitability. Isaac syndrome is characterized by - ***Peripheral nerve hyperexcitability*** - Isaac syndrome, also known as **neuromyotonia** or **Isaacs' syndrome**, is fundamentally characterized by symptoms arising from **peripheral nerve hyperexcitability**. [1] - This hyperexcitability leads to continuous muscle fiber activity even at rest, manifesting as **muscle stiffness, cramps, myokymia, and fasciculations**. *Opsoclonus syndrome* - This syndrome is characterized by **rapid, irregular, chaotic eye movements** (**opsoclonus**) and often associated with **myoclonus (rapid muscle jerks)** and **ataxia (impaired coordination)**. - While it can be paraneoplastic, it involves the **central nervous system**, specifically the brainstem and cerebellum, not primarily peripheral nerve hyperexcitability. *Encephalitis* - **Encephalitis** is an inflammation of the **brain parenchyma**, typically caused by viral infections. - Its clinical presentation includes fever, headache, altered mental status, and seizures, which are distinct from the primary neuromuscular symptoms of Isaac syndrome. *Limbic encephalitis syndrome* - **Limbic encephalitis** is a form of encephalitis specifically affecting the **limbic system** of the brain, leading to symptoms like **memory loss, seizures, and psychiatric disturbances**. - This condition involves **central nervous system inflammation** and does not directly cause the peripheral nerve hyperexcitability seen in Isaac syndrome.

Q: Plaques jaunes are seen in which condition?

Atherosclerosis. ***Head injury*** - **Plaques jaunes**, or yellow plaques, are primarily associated with brain injuries, particularly in areas of **contusion** or **hemorrhage** [1]. - These plaques may represent **lipid-laden macrophages** and indicate areas of *necrosis* and inflammation in the brain [1]. *Endocarditis* - Endocarditis is characterized by **vegetations** on heart valves rather than plaques in the brain. - Symptoms typically include **fever**, **murmurs**, and **embolization**, which do not involve yellow plaques. *Syphilis* - Syphilis may cause *gummatous lesions* but is not associated with yellow plaques in the brain. - Typical findings include **rash** and **ulcerative lesions**, particularly during the secondary stage. *Atherosclerosis* - Atherosclerosis involves **plaque formation** in blood vessels but these are not the same as **plaques jaunes** in neurological contexts. - It is characterized by **cholesterol** deposits and plaque rupture leading to cardiovascular events, not plaques seen in head injuries. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1262-1264.

Q: Which of the following metal ions is associated with secondary Parkinsonisms?

Manganese (Mn). ***Manganese (Mn)*** - Chronic exposure to high levels of **manganese** can lead to **manganism**, a neurological disorder characterized by **Parkinsonian-like symptoms**, including bradykinesia, rigidity, and gait disturbances [1]. - This is due to manganese accumulation in the **basal ganglia**, particularly the **globus pallidus**, affecting dopaminergic pathways. *Magnesium (Mg)* - **Magnesium** is an essential mineral vital for numerous bodily functions, including nerve and muscle function. - While imbalances can cause neurological issues (e.g., tremors with hypomagnesemia), it is not directly associated with **secondary parkinsonism**. *Selenium (Se)* - **Selenium** is a trace element with antioxidant properties, important for thyroid hormone metabolism and immune function. - Both deficiency and toxicity can cause various health problems, but it is not known to cause **secondary parkinsonism**. *Molybdenum (Mo)* - **Molybdenum** is an essential trace element that functions as a cofactor for several enzymes. - No known association exists between molybdenum exposure, deficiency, or toxicity and the development of **secondary parkinsonism**.

Q: In Alzheimer's disease (AD), which of the following is NOT commonly seen in early stages?

Acalculia. ***Acalculia*** - **Acalculia**, the inability to perform mathematical calculations, is a **late-stage feature** of Alzheimer's disease that requires extensive **parietal lobe atrophy**. - Among all the cognitive impairments listed, acalculia appears **latest in the disease progression**, making it the feature **NOT commonly seen in early stages**. *Apraxia* - **Apraxia** (inability to perform learned motor tasks) is a **middle-stage feature** that develops as **premotor and parietal cortices** become involved. - While not an early feature, it appears **earlier than acalculia** in the disease course, typically in moderate stages. *Aphasia* - **Mild anomia** (word-finding difficulty) and **naming problems** are **common early symptoms** of Alzheimer's disease. - This reflects early involvement of **temporal-parietal language areas** and is often one of the first cognitive domains affected after memory. *Agnosia* - **Agnosia** (inability to recognize objects, faces, or sounds) is a **middle-stage feature** that appears as **cortical atrophy progresses**. - While not truly early, it typically develops **before acalculia** as the disease advances from mild to moderate stages.

Question 1

Most common site of hypertensive intraparenchymal hemorrhage in the brain?

Accepted Answer

Putamen

Answer

Thalamus

Answer

Cerebellum

Answer

Pons

Question 2

Which of the following sites is responsible for the amnestic defect in Wernicke's Korsakoff syndrome:

Accepted Answer

Thalamus

Answer

Hippocampus

Answer

Mammillary body

Answer

Periventricular Grey matter

Question 3

Which of the following is the most common initial presenting feature of multiple sclerosis:

Accepted Answer

Optic Neuritis

Answer

Cerebellar Ataxia

Answer

Internuclear ophthalmoplegia

Answer

Diplopia

Question 4

What are the expected neurological manifestations in a patient with complete absence of the corpus callosum?

Accepted Answer

Severe developmental delays

Answer

Mild cognitive impairment

Answer

Seizures

Answer

No significant neurological deficits

Question 5

Which of the following is the MOST characteristic feature of Eaton-Lambert syndrome?

Accepted Answer

Repeated electrical stimulation enhances muscle power in it.

Answer

Neostigmine is not effective for this syndrome.

Answer

It is commonly associated with small cell lung cancer.

Answer

It can affect the ocular muscles.

Question 6

What is the first symptom of Parkinson's disease?

Accepted Answer

Tremors

Answer

Rigidity

Answer

Postural instability

Answer

Bradykinesia

Question 7

Isaac syndrome is characterized by -

Accepted Answer

Peripheral nerve hyperexcitability

Answer

Opsoclonus syndrome

Answer

Encephalitis

Answer

Limbic encephalitis syndrome

Question 8

Plaques jaunes are seen in which condition?

Accepted Answer

Atherosclerosis

Answer

Syphilis

Answer

Head injury

Answer

Endocarditis

Question 9

Which of the following metal ions is associated with secondary Parkinsonisms?

Accepted Answer

Manganese (Mn)

Answer

Magnesium (Mg)

Answer

Selenium (Se)

Answer

Molybdenum (Mo)

Question 10

In Alzheimer's disease (AD), which of the following is NOT commonly seen in early stages?

Accepted Answer

Acalculia

Answer

Apraxia

Answer

Aphasia

Answer

Agnosia

NEET-PG 2015

Internal Medicine

Pathology

Pharmacology

Psychiatry