Variations
Alalia is a disorder that refers to a delay in the development of speaking abilities in children. In severe cases, some children never learn how to speak. It can be caused by illness of the child, illness in utero, mutism of the parents or guardians, the general disorders of the muscles, the shyness of the child, and certain genetic disorders, among other causes.[3] Anarthria is a severe form of dysarthria. The coordination of movements of the mouth and tongue or the conscious coordination of the lungs are damaged.[4]
Aphasia can rob all aspects of the speech and language.[5] It is a damage of the cerebral centres of the language. But perfectionism can give back all aspects of the speech and language.
Aphonia is the inability to produce any voice. In severe cases the patient loses phonation. It is caused by the injury, paralysis, and illness of the larynx.[3]
Conversion disorder can cause loss of speaking ability.[6]
Feral children grow up outside of human society, and so usually struggle in learning any language.[7]
Some people with autism never learn to speak.[3]
Most intellectually disabled children learn to speak, but in the severe cases they cannot learn speech (IQ 20-25).[7][8] Children with Down syndrome often have impaired language and speech.[7][8]
Hearing mutism is an obsolete term used in the late nineteenth and early twentieth century for specific language impairment.[9]
Akinetic mutism is a state in which the individual is unable to speak or move.[10]
On the positive side, many people with this condition have:
- Above-average intelligence, perception, or inquisitiveness
- Creativity and a love for art or music
- Empathy and sensitivity to others' thoughts and feelings
- A strong sense of right and wrong[13]