Practice Test GeeksNBME Practice Test
← All NBME Flashcard Decks

Neuroscience Flashcards

7 cards from real NBME practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Neuroscience flashcards as text

  1. Preganglionic sympathetic neurons originate at which spinal cord levels, and they synapse in which structure before reaching their effectors?

    Answer: Thoracolumbar (T1-L2); paravertebral or prevertebral ganglia

    Sympathetic preganglionic neurons arise from the thoracolumbar cord (T1–L2) and synapse in the paravertebral sympathetic chain ganglia or prevertebral ganglia (celiac, superior mesenteric, aorticorenal).

  2. The primary somatosensory cortex (SI) is located in the postcentral gyrus. Which thalamic nucleus relays somatic sensory information to this cortex?

    Answer: Ventral posterior lateral (VPL) and ventral posterior medial (VPM) nuclei

    The VPL nucleus relays body sensation (via spinothalamic and medial lemniscal tracts) and VPM relays facial sensation (via trigeminothalamic tracts) to the postcentral gyrus (SI).

  3. Antipsychotic drugs block D2 receptors in the nigrostriatal pathway. This blockade leads to which adverse effect?

    Answer: Extrapyramidal symptoms (EPS) such as parkinsonism and tardive dyskinesia

    D2 blockade in the nigrostriatal pathway causes extrapyramidal side effects including acute dystonia, akathisia, parkinsonism (early), and tardive dyskinesia (late with chronic use).

  4. Pain and temperature from the body ascend to the thalamus via which pathway, and where do they first synapse after entering the spinal cord?

    Answer: Lateral spinothalamic tract; dorsal horn (Rexed laminae I and V)

    Pain and temperature fibers (Aδ and C) synapse in ipsilateral dorsal horn laminae I and V, decussate in the anterior commissure within 1-2 levels, and ascend in the contralateral lateral spinothalamic tract to the VPL thalamus.

  5. A child presents with a posterior fossa tumor compressing the fourth ventricle, causing obstructive hydrocephalus. Dilated ventricles are due to impaired flow at which anatomical location?

    Answer: Cerebral aqueduct of Sylvius or fourth ventricle outflow foramina

    Obstruction at or near the fourth ventricle (cerebral aqueduct, foramina of Luschka/Magendie) causes non-communicating (obstructive) hydrocephalus with dilatation of all upstream ventricles.

  6. Stimulation of which receptor type by norepinephrine results in mydriasis (pupil dilation)?

    Answer: Alpha-1 adrenergic receptors on the dilator pupillae

    Sympathetic norepinephrine activates α1-adrenergic receptors on the radial dilator pupillae muscle, causing contraction and mydriasis; loss of sympathetic tone (Horner's) causes miosis.

  7. A patient with a right middle cerebral artery stroke develops left hemispatial neglect and anosognosia. These deficits are most associated with damage to which cortical region?

    Answer: Right parietal lobe (non-dominant hemisphere)

    Hemispatial neglect and anosognosia result from right (non-dominant) parietal lobe damage (especially right angular and supramarginal gyri), which mediates attention to both sides of space.