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hello again more on how our incredible brains work. janet ------------------------------------------------------------------------- Clues To How The Brain Processes Words And Pictures Uncovered ------------------------------------------------------------------------- WESTPORT, Sep 19 (Reuters) - Some brain-damaged patients can name objects from pictures but not from verbal descriptions. Other patients have the reverse deficit. Now, British researchers have identified the structures in the brain that are activated when people make semantic judgments based on words or pictures. In today's issue of Nature, Dr. Cathy Price and colleagues at the Institute of Neurology in London report, "We contrasted activity during two semantic tasks... and a baseline task... performed either with words or with pictures." According to Dr. Price, positron emission tomography studies showed that, "...semantic tasks activate a distributed semantic processing system shared by both words and pictures, with a few specific areas differentially active for either words or pictures." She adds, "The anatomy and function of the common semantic processing stream we describe suggests that... when primates acquired language, a preexisting object-recognition system could have been adapted to attribute meaning to nouns." In an accompanying News and Views article, Dr. Alfonso Caramazza of the Cognitive Neuropsychology Laboratory at Harvard University points out that, in the study by Dr. Price's group, "...the areas that showed selective activation for type of stimulus (picture or word) did so for both visual and functional/associative judgments. This result shows that the areas selectively activated for pictures and for words are not modality-specific semantic systems but neural mechanisms involved in the recognition of pictures and words, respectively." Dr. Caramazza concludes that "...it is clear that we are entering an exciting new phase in the study of the human brain; functional neuroimaging studies ..promise to answer increasingly finer-grained questions about the organization of language processes in the brain." Nature 1996;383:254-256,216-217. Westport Newsroom 203 221 7648 ------------------------------------------------------------------------- [log in to unmask]