We report on two brain-damaged subjects who exhibit the uncommon pattern of loss of object color knowledge, but spared color perception and naming. The subject P.C.O., as in previously reported patients, is also impaired in processing other perceptual and functional properties of objects. I.O.C., in contrast, is the first subject on record to have impaired object color knowledge, but spared knowledge of object form, size and function. This pattern of performance is consistent with the view that semantic information about color and other perceptual properties of objects is grounded in modality-specific systems. Lesion analysis suggests that such grounding requires the integrity of the mesial temporal regions of the left hemisphere.

There are two views about the nature of consonants and vowels. One view holds that they are categorically distinct objects that play a fundamental role in the construction of syllables in speech production. The other view is that they are convenient labels for distinguishing between peak (vowel) and non-peak (consonant) parts of a continuous stream of sound that varies in sonority (roughly the degree of openness of the vocal apparatus during speech), or that they are summary labels for bundles of feature segments. Taking the latter view, consonants and vowels do not have an independent status in language processing. Here we provide evidence for the possible categorical distinction between consonants and vowels in the brain. We report the performance of two Italian-speaking aphasics who show contrasting, selective difficulties in producing vowels and consonants. Their performance in producing individual consonants is independent of the sonority value and feature properties of the consonants. This pattern of results suggests that consonants and vowels are processed by distinct neural mechanisms, thereby providing evidence for their independent status in language production.

In surgery for tumors of the dominant hemisphere, the attention devoted to quality of resection and preservation of language function has not been accompanied by comparable interest in preservation of cognitive abilities which may affect quality of life. We studied 22 patients undergoing awake surgery for glioma removal in the language areas of the brain. Besides monitoring tumor variables (size, location, histology, edema), we used a multifaceted battery of tests to investigate mood, cognition, and language in an attempt to assess the burden of disease and treatment, and the relationships between these three dimensions. Baseline assessment showed that 45% of the patients were depressed and 23% anxious; some cognitive and language impairment was noted for 59 and 50%, respectively. A general decline in postoperative cognitive performance (significant for memory and attention only) and language function (significant for picture naming) was observed, whereas depression was unchanged and anxiety decreased. Tumor histology, but not demographic variables or extent of resection, correlated with postoperative cognitive changes: patients undergoing surgery for high-grade tumors were more likely to improve. No correlation was observed between scores for mood, cognition, and language function. A subset of patients with low-grade glioma was followed up for 3-6 months; although some improvement was observed they did not always regain their preoperative performance. In conclusion, we believe that cognitive assessment performed in conjunction with language testing is a necessary step in the global evaluation of brain tumor patients both before and after surgery.