舌喑者，中风而舌不转运，舌强不能言是也。经曰∶喉咙者，气之所以上下；会厌者，
声音之户；舌者，声音之机；唇者，声音之扇；横骨者，神气所使，主发舌者也。舌为心之
苗，然心之本脉系于舌根，脾之络脉系于舌旁，肝脉循阴器络于舌本，少阴之脉走喉咙系舌
本；足四经之脉，皆上于舌。邪中其经，则痰涎闭其脉道，舌不能转运，而为之喑矣。有喉
喑者，劳嗽失音，即喉咙声哑是也。故喉喑者，喉中之声嘶，而舌本能言；舌喑者，舌本不
能言，而喉中之声如故。中风而舌喑者，舌与喉俱病，而音声不能发于会厌也。然有外感内
伤之因，外感者，风寒火热之邪也；经曰∶诸病暴喑，皆属于火。内伤者，心肺肾三经致病
，亦多由痰火壅塞上窍，气血两虚，不能上荣，则舌机不转也；有肾虚而气不归源，内夺而
胞络内绝，不能上接清阳之气者；有元气不足，肺无所资者；有血衰而心失所养者。盖心为
声音之主，肺为声音之户，肾为声音之根。经曰∶三焦之气通于喉咙，气弱则不能上通矣。
治者能于根本用力，则丹田清阳之气，自能宣扬振作，故古人每以独参汤、地黄饮子取效也
。
舌痹者，强而麻也。乃心绪烦扰，忧思暴怒，气凝痰火所致。夫舌固属心脾，而肝脉亦
络舌本。故伤寒邪传厥阴，则舌卷囊缩而不言；七情所郁，则舌肿满口而不得息；心热则舌
裂而疮；脾热则舌滑而胎；脾闭则舌白胎如雪；肝热则舌木而硬。若人无故舌痹者，不可作
风热治，盖由心血不足、血虚火烁耳，理中汤合四物汤主之。
舌喑，是指中风导致舌头僵硬、不能灵活转动，表现为舌体强硬且无法言语。《内经》说：喉咙是气机上下通行的通道；会厌是发出声音的门户；舌头是控制声音的关键机关；嘴唇是辅助发声的扇子；横骨受神气的支配，主要主管舌头的运动。舌是心的外候（苗窍），心的本脉连接在舌根，脾的络脉连接在舌旁，肝脉沿着生殖器上行并联络于舌根，少阴经脉经过喉咙并联络于舌根；足部四条经脉的气血都上达于舌。如果邪气中伤经络，就会导致痰涎阻塞脉道，使舌头不能灵活转动，从而发生失音。
有一种情况叫“喉喑”，是由于劳累咳嗽导致的声音嘶哑，即喉咙声音沙哑。所以，“喉喑”的特点是喉咙声音嘶哑，但舌根功能正常，仍能言语；而“舌喑”的特点是舌根本身不能言语，但喉咙里的声音依然如常。如果是中风引起的舌喑，则是舌头和喉咙同时患病，导致声音无法从会厌发出。
然而，引起失音的原因有外感和内伤之分。外感方面，是风寒火热等邪气所致；《内经》说：“各种突然发生的失音，都属于火。”内伤方面，多由心、肺、肾三经病变引起，也常常是因为痰火壅塞在上部孔窍，加上气血两虚，不能上荣滋养，导致舌的运动机关失灵。有的因为肾虚导致气不归元，内部精气亏损，胞络隔绝，不能向上承接清阳之气；有的因为元气不足，肺脏缺乏资助；有的因为血液衰少，心脏失去滋养。大概来说，心是声音的主宰，肺是声音的门户，肾是声音的根本。《内经》说：三焦之气通连喉咙，气虚弱就不能向上通达。治疗时如果能从根本上下功夫，丹田中的清阳之气自然能够宣扬振作，所以古人常用独参汤、地黄饮子来取得疗效。
舌痹，表现为舌头僵硬且麻木。这是由于心神烦扰，忧思或暴怒，导致气机凝滞、痰火内生所致。舌头虽然属于心和脾，但肝脉也联络于舌根。所以，伤寒邪气传入厥阴经时，会出现舌头卷曲、睾丸收缩而不能说话；七情郁结，会导致舌头肿胀充满口腔而无法呼吸；心热则舌头开裂生疮；脾热则舌头滑腻且有苔；脾脏闭塞则舌苔白如雪；肝热则舌头麻木且坚硬。如果人无缘无故出现舌痹，不能当作风热来治疗，这通常是由于心血不足、血虚导致虚火灼烧所致，治疗应以理中汤合四物汤为主。
She Yin (Tongue Aphasia) refers to the condition where, following wind-stroke, the tongue becomes stiff and immobile, manifesting as rigidity of the tongue and inability to speak. The Classics state: "The throat is the pathway for Qi to ascend and descend; the epiglottis is the gate of voice; the tongue is the mechanism of voice; the lips are the fan of voice; the transverse bone is directed by Shen-Qi and primarily governs the movement of the tongue." The tongue is the sprout of the Heart. However, the main meridian of the Heart connects to the root of the tongue, the collateral meridians of the Spleen connect to the sides of the tongue, the Liver meridian circulates along the genitalia and connects to the root of the tongue, and the Shaoyin meridian passes through the throat and connects to the root of the tongue; the meridians of the four foot-yang and foot-yin channels all ascend to the tongue. If pathogenic factors strike the meridians, phlegm and saliva may block the vascular pathways, rendering the tongue immobile and causing aphasia.
There is a condition called Hou Yin (Throat Aphasia), which results from chronic coughing due to exhaustion leading to hoarseness, i.e., a husky voice originating in the throat. Therefore, in Hou Yin, the voice in the throat is hoarse, but the root of the tongue functions normally allowing speech; whereas in She Yin, the root of the tongue cannot produce speech, while the voice in the throat remains normal. In cases of wind-stroke causing She Yin, both the tongue and throat are diseased, preventing sound from being emitted via the epiglottis.
However, causes can be classified into external contraction and internal injury. Regarding external contraction, it is caused by pathogenic factors such as wind-cold or fire-heat; the Classics state: "All sudden cases of aphasia belong to Fire." Regarding internal injury, diseases often arise from the Heart, Lung, and Kidney meridians, frequently due to phlegm-fire obstructing the upper orifices, combined with deficiency of both Qi and Blood failing to nourish the upper regions, thus impairing the motor function of the tongue. Some cases involve Kidney deficiency where Qi fails to return to its source, internal depletion severing the Bao-Luo (uterine/energy network), preventing the upward connection of Clear Yang Qi. Others involve insufficient Yuan Qi, leaving the Lung without support; still others involve blood deficiency, depriving the Heart of nourishment. Generally, the Heart is the master of voice, the Lung is the gate of voice, and the Kidney is the root of voice. The Classics state: "The Qi of the San Jiao communicates with the throat; if Qi is weak, it cannot ascend." When treating, if effort is applied to the root, the Clear Yang Qi from the Dantian will naturally promote and invigorate itself. Thus, ancient physicians often achieved efficacy using Dushen Tang (Single Ginseng Decoction) and Dihuang Yinzi (Rehmannia Infusion).
She Bi (Tongue Numbness) manifests as stiffness and numbness of the tongue. It is caused by mental disturbance, excessive worry or thought, or sudden anger, leading to Qi stagnation and the generation of phlegm-fire. Although the tongue belongs to the Heart and Spleen, the Liver meridian also connects to the root of the tongue. Therefore, when Shaoyin cold damage pathogens transmit to the Jueyin channel, symptoms include tongue retraction and testicular contraction with inability to speak; when constrained by seven emotions, the tongue swells filling the mouth causing difficulty breathing; Heart heat causes tongue fissures and sores; Spleen heat causes a slippery tongue with coating; Spleen closure results in a white tongue coating like snow; Liver heat causes the tongue to feel woody and hard. If a person experiences spontaneous She Bi, it should not be treated as wind-heat, as it is typically due to insufficiency of Heart Blood and fire scorching from blood deficiency. The treatment principle involves using Lizhong Tang (Regulate the Middle Decoction) combined with Siwu Tang (Four Substances Decoction).