Pain signals from the lateral extremities travel via________________?
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Answer: A. Spino thalmamic tract
Explanation
Pain and temperature sensations from the contralateral side of the body are conveyed via this pathway. First-order neurons synapse in the spinal cord before crossing over to ascend in the spinothalamic tract. Lesions within this specific sensory pathway result in contralateral loss of pain and thermal sensations. Sensory pathways transmit information from peripheral receptors to the primary somatosensory cortex in the brain. The spinothalamic tract is a major ascending pathway located in the anterolateral white matter of the cord. Decussation occurs near the entry level in the spinal cord, distinguishing it from dorsal column pathways.
Neurological examinations test pain and temperature perception to locate potential spinal cord injuries or strokes. Syringomyelia can selectively damage crossing fibers of the spinothalamic tract, causing loss of pain sensation. Understanding sensory pathways helps physicians localize lesions accurately during complex neurological patient evaluations. The dorsal column pathway transmits fine touch, conscious proprioception, and vibration sensation to the brain. The corticospinal tract is a descending motor pathway controlling voluntary movement of skeletal muscles. The spinocerebellar tract conveys unconscious proprioceptive information to the cerebellum for motor coordination.
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