**Question:** Vibration sensation is mediated by

A. C-fibers
B. A-delta fibers
C. A-alpha fibers
D. A-beta fibers

**Correct Answer:** D. A-beta fibers

**Core Concept:** Vibration sensation is a type of somatosensory perception that allows an individual to detect and discriminate vibrations applied to the skin or other body parts. This sensation is mediated by specific types of nerve fibers in the peripheral nervous system.

**Why the Correct Answer is Right:** Vibration sensation is primarily mediated by A-beta fibers, which are thin myelinated sensory neurons responsible for transmitting information about mechanical stimuli, such as vibration. These fibers have a faster conduction velocity compared to A-delta and C-fibers, allowing for quick detection and discrimination of vibrations.

**Why Each Wrong Option is Incorrect:**

A. C-fibers: These are unmyelinated fibers involved in transmitting information about touch, pressure, and pain. They have slower conduction velocities and are not responsible for vibration sensation.

B. A-delta fibers: These are thin myelinated fibers primarily responsible for transmitting information about sharp pain and cold sensation. They are not involved in detecting vibrations.

C. A-alpha fibers: These are medium-sized myelinated fibers that transmit information related to light touch and proprioception. They are not responsible for vibration sensation.

**Clinical Pearl:** Vibration sensation is essential for various clinical applications, such as detecting bone abnormalities and assessing peripheral nerve function. Aberrations in vibration perception threshold can serve as an indicator of peripheral nerve damage, neuropathy, or other neurological disorders.

**Explanation:**

In the context of somatosensory perception, A-beta fibers are the primary sensory neurons responsible for transmitting information about vibrations. These fibers have faster conduction velocities, allowing for efficient detection and discrimination of vibrations. The other options (C-fibers, A-delta fibers, and A-alpha fibers) are involved in transmitting information about different modalities (touch, pain, proprioception), but they are not responsible for vibration sensation.