The content boundaries of natural categories in high-functioning young adults with autism spectrum disorders

The present study evaluated the functioning and structuring of semantic knowledge for naturalcategories in Autism Spectrum Disorders (ASD). A sample of high-functioning adults (HFA) withASD (n = 20) and a sample of typical developed individuals (n = 20) (matched for age, education,and verbal IQ) performed two tasks with natural concepts: a task of semantic access from pictures(the Camel and Cactus test) and a semantic matching-to-sample task, designed to evaluate category boundaries and structure. Overall, the HFA group showed preserved access to conceptual knowledge but some irregularities in category structure as reflected by the increased in typical errors found in the matching-to-sample task. This pattern of under generalization is suggestive of categories that have an abnormal and restricted content, missing out the typical instances

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved