体感，或称躯体感觉，是触觉、压觉、温觉、痛觉和本体感觉（关于肌肉和关节位置和运动、躯体姿势和运动以及面部表情的感觉）的总称。体感是和特殊感觉相对的一个概念。这些不同的体感模式源自不同类型的感受器。在哺乳类，体感的上行神经通路起源自身体不同部位的感受器，途经后柱-内侧丘系通路、脊髓丘脑前束、脊髓皮层前束和脊髓皮质后束，终于大脑皮层后中央回的体感皮层。

上行体感通路通常包括三个神经元：分别称为一级，二级和三级神经元。一级神经元的胞体位于脊髓后根神经节（头和颈部以外的部分），或三叉神经节或其它感觉性脑神经的神经节（头和颈部）。二级神经元的胞体位于脊髓或脑干内，其轴突将交叉并进入对侧丘脑。三级神经元的胞体位于丘脑腹后核，其轴突终于大脑皮质后中央回，即初级体感皮层。

The somatosensory system (also somatosensory nervous system or SNS) is a complex system of nerve cells that responds to changes to the surface or internal state of the body. Nerve cells called "sensory receptors" (including thermoreceptors, mechanoreceptors, chemoreceptors and nociceptors) send signals along a chain of nerve cells to the spinal cord where they may be processed by other nerve cells and then relayed to the brain for further processing. Sensory receptors are found in many parts of the body including the skin, epithelial tissues, skeletal muscles, bones and joints, internal organs, and the cardiovascular system.