Which layer of the skin is primarily involved in sensation?

The dermis is primarily responsible for sensation due to its rich supply of nerve endings and sensory receptors. This layer of the skin contains structures such as mechanoreceptors, which respond to touch, pressure, and vibration, as well as free nerve endings that detect pain and temperature. The presence of these sensory receptors allows the dermis to communicate sensory information to the brain about the environment.

In contrast, the epidermis, while critical for barrier functions and protection, has a limited role in sensory perception because it is primarily composed of keratinocytes which do not have significant sensory functions. The hypodermis, also known as the subcutaneous layer, primarily serves as insulation and energy storage and does not play a direct role in sensation. Thus, the dermis is correctly identified as the layer primarily involved in sensation.