During a neurological examination, a patient cannot tell with his eyclosed whether the neurologist flexed or extended his toe, there is likely damage to:

Correct Answer: D

Rationale: The dorsal column medial lemniscal pathway . This pathway carriconscious proprioception (position sense), vibration, and fine touch. Damage prevents the patient from sensing toe position with eyclosed. Choice A (spinothalamic) carripain and temperature, not proprioception. Choice B (precentral gyrus) is motor, not sensory. Choice C (ventral spinal cord) affects motor tracts, not proprioception. Thus, D identifithe correct pathway for position sense, making it the right answer.

Correct Answer: B

Rationale: Transmitted by A-alpha . Fast pain, sharp and localized, is transmitted by A-delta fibers, not A-alpha, which carry proprioception and motor signals. Choice A is correct (less emotional than slow pain, C-fiber mediated). Choice C is true (synapsin laminae I and V of dorsal horn). Choice D is accurate (superficial, well-localized). Thus, B misattributfast pain to A-alpha instead of A-delta, making it the wrong statement and the correct answer.

Correct Answer: C

Rationale: Unconscious muscle joint sense travels in the anterior spinocerebellar tract . The anterior spinocerebellar tract carriunconscious proprioception from lower limbs to the cerebellum via the superior cerebellar peduncle. Choice A is wrong (two-point discrimination is dorsal column). Choice B is incorrect (pain is lateral spinothalamic). Choice D is false (no posterior spinothalamic tract; pressure is anterior spinothalamic). Thus, C accurately pairs the sensation and pathway, making it correct.

Correct Answer: D

Rationale: The anterior spinothalamic tract terminatin the ventral posterolateral nucleus of the thalamus . The anterior spinothalamic tract (crude touch) terminatin the VPL nucleus of the thalamus, relaying to the cortex. Choice A is wrong (posterior columns end in nucleus gracilis/cuneatus). Choice B is false (spinoreticular ends in reticular formation). Choice C is incorrect (spinotectal ends in superior colliculus). Thus, D is accurate, making it correct.

Correct Answer: B

Rationale: Cervical region . The lateral corticospinal tract, controlling voluntary movement, has most fibers synapsing in the cervical region (C1-C8), innervating upper limbs for fine motor skills (e.g., hands). Choice A (thoracic) is less dominant. Choice C (coccygeal) and D (lumbar) target lower body, with fewer fibers. Thus, B reflects the tracts primary focus, making it correct.