Disorders of the special senses (i.e., VISION; HEARING; TASTE; and SMELL) or somatosensory system (i.e., afferent components of the PERIPHERAL NERVOUS SYSTEM).

Subjective cutaneous sensations (e.g., cold, warmth, tingling, pressure, etc.) that are experienced spontaneously in the absence of stimulation.

感觉障碍指在反映刺激物个别属性的过程中出现困难和异常。常见的感觉障碍有:①感觉过敏:对外界刺激的感受能力异常增高。②感觉减退和感觉缺失:对外界刺激的感受能力下降。③感觉倒错:对外界刺激物的性质产生错误的感觉。④内感性不适:对躯体内部刺激产生异样的不适感或疼痛。有关感觉障碍的脑机制的心理学研究，肯定了人类大脑皮层中央沟后部区域的损伤与感觉障碍的发生有关。感觉障碍对人的各种心理过程会发生广泛的影响，并可由此造成知觉障碍，使运动反馈信息紊乱而导致运动功能失调。在临床上，神经病和精神病都可有感觉障碍症状，前者更为多见。治疗应找出引起感觉障碍的原发疾病，针对病因进行治疗。

Dysesthesia means "abnormal sensation". Its etymology comes from the Greek word "dys," meaning "bad," and "aesthesis," which means "sensation" . It is defined as an unpleasant, abnormal sense of touch. It often presents as pain but may also present as an inappropriate, but not discomforting, sensation. It is caused by lesions of the nervous system, peripheral or central, and it involves sensations, whether spontaneous or evoked, such as burning, wetness, itching, electric shock, and pins and needles. Dysesthesia can include sensations in any bodily tissue, including most often the mouth, scalp, skin, or legs.

Absent or reduced sensitivity to cutaneous stimulation.