Abstract
Although many drugs are known to alter the form and articulation of speech, surprisingly little systematic work has been done to study any possible interactions. Following reception and understanding of the written or spoken word, or when spontaneous speech has been initiated, several processes need to interact. The higher functions which determine the content of speech as opposed to its syntactic structure, can certainly be adversely affected by drugs, a fact which has been well recognised for many thousands of years. The next process necessary is some stimulus to initiation of speech itself. This is presumably a frontal lobe function and indeed in many neurological disorders in which the prefrontal areas are damaged, a condition of mutism may result. Mutism, of course, may also be psychological in aetiology.