Little nicholas is learning to speak, and it is clear to his parents that he understands far more words than he can say, psychologists refer to this as a receptive-expressive language lag, it is an alteration in which the receptive and expressive language are significantly below the intellectual level evaluated by standardized tests of non-verbal intellectual capacity. The subjects that suffer it present the symptoms of the Expressive Language Disorder plus those of receptive language, as difficulty to understand particular types of words.
