Classical anomia: a neuropsychological perspective on speech production.

We present data collected from two anomic aphasics. Thorough assessment of comprehension, oral reading and repetition revealed no underlying impairments suggesting that both patients were examples of classical anomia--word-finding difficulties without impaired semantics or phonology. We describe a series of experiments in which the degree of anomia was both increased and decreased, by cueing or priming with either a semantically related word or the target item. One of the patients also presented with an 'acquired' tip-of-the-tongue phenomenon. He was able to indicate with a high-degree of accuracy the syllable length of the target, and whether or not it was a compound word. Neither patient could provide the first sound/letter. The data are discussed in terms of discrete two-stage models of speech production, an interactive-activation theory and a distributed model in which the positive and negative computational consequences of the arbitrary relationship between sound and meaning are emphasised.