Review of Literature on stuttering

Stuttering also known as stammering is a speech disorder in which the flow of speech is disrupted by involuntary repetitions and prolongations of sounds, syllables, words or phrases as well as involuntary silent pauses or blocks in which the person who stutters is unable to produce sounds.
The term stuttering is most commonly associated with involuntary sound repetition, but it also encompasses the abnormal hesitation or pausing before speech, referred to by people who stutter as blocks, and the prolongation of certain sounds, usually vowels and semivowels. For many people who stutter, repetition is the primary problem. Blocks and prolongations are learned mechanisms to mask repetition, as the fear of repetitive speaking in public is often the main cause of psychological unease. The term "stuttering" covers a wide range of severity, encompassing barely perceptible impediments that are largely cosmetic to severe symptoms that effectively prevent oral communication.

The impact of stuttering on a person's functioning and emotional state can be severe. This may include fears of having to enunciate specific vowels or consonants, fears of being caught stuttering in social situations, self-imposed isolation, anxiety, stress, shame, being a possible target of bullying (especially in children), having to use word substitution and rearrange words in a sentence to hide stuttering, or a feeling of "loss of control" during speech. Stuttering is sometimes popularly associated with anxiety but there is actually no such correlation (though as mentioned social anxiety may actually develop in individuals as a result of their stuttering). Stuttering is not an indication of reduced intelligence.
Stuttering is generally not a problem with the physical production of speech sounds or putting thoughts into words. Acute nervousness and stress do not cause stuttering but they can trigger stuttering in people who have the speech disorder, and living with a highly stigmatized disability