Many studies on aphasia have described disproportioned impairment of either verbs or nouns and have broached the issue of mental implementation of the grammatical class distinction.
This paper reports the results of several studies on the mechanisms underlying Verb-Noun (V-N) dissociation. The objectives of the studies were to ascertain the location of the lesions causing predominant V or N impairment and to shed light on the different mental representations of these word classes through analyses of the data from neuropsychological patients.
Aphasic patients occasionally manifest a dissociated naming ability between objects and actions: this phenomenon has been interpreted as evidence of a separate organization for nouns and verbs in the mental lexicon. Nevertheless Bird et al. [Bird, H., Howard, D., Franklin, S. (2000). Why is a verb like an inanimate object? Grammatical category and semantic category deficits.
Letter-by-letter (LBL) dyslexia is a reading impairment caused by left occipital damage and characterized by significant increase in reading time according to the number of letters in a given string (word length effect). In analogy to Dejerine’s (1892) interpretation of
pure alexia, this disorder is said to be the consequence of a disconnection of the word-blind right hemisphere (RH) from the left hemisphere (LH) word recognition system (angular gyrus). According to this view, patients affected by LBL dyslexia would have no
Several authors described cases of dissociated impairment in naming nouns and verbs. There are four accounts of this dissociation: (i) patients may have purely lexical damage, which selectively affects verbs or nouns at a late stage of the linguistic processing (phonological or orthographic lexicons) (Rapp & Caramazza, 2002); (ii) the damage affects a lexical device, either at an ortographic-phonological modality-specific level (the lexeme; Levelt, Roelofs, & Meyer, 1999) or at a unitary lexical–syntactic level (the lemma
