Editor-In-Chief: C. Michael Gibson, M.S., M.D. 
Speech communication refers to the processes associated with the production and perception of sounds used in spoken language. A number of academic disciplines study speech and speech sounds, including acoustics, psychology, speech pathology, linguistics, and computer science.
In linguistics (articulatory phonetics), manner of articulation describes how the tongue, lips, and other speech organs are involved in making a sound make contact. Often the concept is only used for the production of consonants. For any place of articulation, there may be several manners, and therefore several homorganic consonants.
Speech perception refers to the processes by which humans are able to interpret and understand the sounds used in language. The study of speech perception is closely linked to the fields of phonetics and phonology in linguistics and cognitive psychology and perception in psychology. Research in speech perception seeks to understand how human listeners recognize speech sounds and use this information to understand spoken language. Speech research has applications in building computer systems that can recognize speech, as well as improving speech recognition for hearing- and language-impaired listeners.
Problems involving speech
There are several biological and psychological factors that can affect speech. Among these are:
- Diseases and disorders of the lungs or the vocal cords, including paralysis, respiratory infections, vocal fold nodules and cancers of the lungs and throat.
- Diseases and disorders of the brain, including alogia, aphasias, dysarthria, dystonia and speech processing disorders, where impaired motor planning, nerve transmission, phonological processing or perception of the message (as opposed to the actual sound) leads to poor speech production.
- Hearing problems, such as otitis media effusion can lead to phonological problems.
- Articulatory problems, such as stuttering, lisping, cleft palate, ataxia, or nerve damage leading to problems in articulation. Tourette syndrome and tics can also affect speech.
- In addition to aphasias, anomia and certain types of dyslexia can impede the quality of auditory perception, and therefore, expression. Hearing impairments and deafness can be considered to fall into this category.