Advanced Neurology Certification Preparation Quiz

X-linked disorders are genetic conditions that result from mutations in genes on the X chromosome. Since males have only one X chromosome, they are more likely to be affected by X-linked disorders compared to females who have two X chromosomes.

Porencephaly is characterized by a cleft lined by white matter in the brain, typically caused by intrauterine insult. Schizencephaly, holoprosencephaly, and hydrocephalus are all different brain conditions with distinct features.

Lissencephaly, a rare brain malformation, can be caused by mutations in various genes. LIS-1 and Reelin are two important genes associated with lissencephaly. Mutations in DCX (Doublecortin), TUBA1A (Alpha tubulin), and PAFAH1B1 (LIS1 protein) are also known to contribute to different forms of lissencephaly.

Megalencephaly is most commonly associated with a group of metabolic and genetic disorders such as GM1 and GM2 gangliosidosis, MPS, Alexanders, Canavans, and TSNF1. Huntington's disease, Crohn's disease, and Marfan syndrome are not typically linked to megalencephaly.

The correct answer specifies closed lip schizencephaly as the defect along with intrauterine insult as the most common etiology. Holoprosencephaly, agenesis of the corpus callosum, and Dandy-Walker malformation are different defects with their respective etiologies.

Corticospinal tracts typically myelinate by the age of 2 years, which is associated with the presence of the Babinski reflex. The incorrect answers are related to different reflexes that are not specifically associated with the myelination of corticospinal tracts during early childhood.

The correct answer states that CNS myelination begins in the 3rd trimester and continues for about 2 years postnatally, with subcortical association fibers in the frontal cortex not completing until adulthood.

The correct answer refers to bilateral periventricular nodular heterotopia which is commonly X-linked and almost always affects females. The incorrect answers provide variations in defects, etiologies, and affected populations to confuse the respondents.

During embryonic development, the neural plate, which is derived from the ectoderm, forms in response to signaling from the notochord. This process occurs around the 3rd week of gestation.

The correct answer is day 28 with folic acid. The closure of the anterior and posterior neuropores is crucial for proper development of the central nervous system in the embryo.

Arcuate scotoma is a visual field defect characterized by a partial loss of vision in an arc-shaped pattern. It is typically associated with nerve fiber bundle defects, such as those seen in conditions like glaucoma.

Sector scatoma or defects can be caused by a variety of eye conditions, but are most commonly associated with retinal lesions.

Central field defects are often associated with damage to specific parts of the visual pathway, including the optic nerve, macula, and papillomacular bundle.

Junctional scotoma is a specific type of visual field defect that is caused by an anterior chiasm lesion, impacting vision in the affected area. Optic neuritis, retinitis pigmentosa, and macular degeneration are other types of eye conditions that can cause visual impairments but are not associated with anterior chiasm lesions.

The correct answer describes a specific visual field defect caused by occlusion of a specific artery leading to infarctions in the lateral geniculate body. The incorrect answers involve different types of visual field defects caused by alternative mechanisms, helping to distinguish the unique characteristics of the correct answer.

Macular sparing is a visual phenomenon where the center of the visual field (macula) remains relatively unaffected despite damage to other parts of the visual field. This is typically seen with occipital lesions affecting the visual cortex at the back of the brain.

The incorrect answers provided do not describe midbrain syndromes. Korsakoff's is associated with alcohol-related cognitive impairment, Virchow-Robin spaces are perivascular spaces in the brain, and Broca's aphasia is a language disorder associated with frontal lobe damage.

Lesions presenting like cavernous sinus lesions, but without Horner's syndrome or V2 involvement, are often localized to the superior orbital fissure due to its proximity and similar symptoms.

The trochlear nerve is unique in that its axons decussate (cross over to the opposite side of the brain) within the midbrain. This anatomical feature is important to consider when evaluating lesions and their resulting symptoms.

A lesion of Dorello's canal typically leads to Gradenigo's syndrome, which presents with specific symptoms including sixth nerve palsy, facial pain, and hearing loss on the same side as the lesion.

Internuclear Ophthalmoplegia (INO) is characterized by weakness in eye adduction and nystagmus upon abduction. In the case of left eye INO, the left eye fails to adduct with right gaze and nystagmus is seen in the right eye during abduction. The incorrect answers provide variations that do not align with typical features of INO of the left eye.

Wall-eyed (eyes bilaterally abducted) is caused by bilateral MLF (Medial Longitudinal Fasciculus) lesions which disrupt the connection between the cranial nerve nuclei responsible for controlling eye movement.

Parinaud's syndrome is a constellation of findings that include light near dissociation, convergence-retraction nystagmus, upward gaze palsy, eyelid retraction (Collier's sign), and skew deviation. Visual field loss, diplopia, and hemiparesis are not typical features of Parinaud's syndrome.

The correct answer describes the specific connections involved in the VOR reflex when the head turns to the left. The incorrect answers provide variations in the activation and inhibition patterns of the abducens nerves, leading to an inaccurate representation of the VOR reflex mechanism.

Gaze evoked amaurosis is primarily caused by tumors near the optic nerve or orbital disease leading to traction on the optic nerve, which results in vision loss upon specific eye movements.

A cherry red spot on the retina is a characteristic finding in central retinal artery (or branch) occlusion, where there is decreased blood flow to the retina leading to ischemia.

Charles Bonnet hallucinations are distinct in that they involve well-formed visual hallucinations specifically of bright objects and people, typically observed in individuals with central visual field defects or ocular diseases like severe cataracts or glaucoma. The incorrect answers do not align with the characteristic features of Charles Bonnet hallucinations.

A Marcus Gunn pupil refers to a phenomenon where the pupil appears to accommodate (change size) when exposed to light but does not react normally. This indicates an afferent pupillary defect.