Abstract:
:In his Philosophical Investigations, Wittgenstein famously noted that the formation of semantic representations requires more than a simple combination of verbal and nonverbal features to generate conceptually based similarities and differences. Classical and contemporary neuroscience has tended to focus upon how different neocortical regions contribute to conceptualization through the summation of modality-specific information. The additional yet critical step of computing coherent concepts has received little attention. Some computational models of semantic memory are able to generate such concepts by the addition of modality-invariant information coded in a multidimensional semantic space. By studying patients with semantic dementia, we demonstrate that this aspect of semantic memory becomes compromised following atrophy of the anterior temporal lobes and, as a result, the patients become increasingly influenced by superficial rather than conceptual similarities.
journal_name
Proc Natl Acad Sci U S Aauthors
Lambon Ralph MA,Sage K,Jones RW,Mayberry EJdoi
10.1073/pnas.0907307107subject
Has Abstractpub_date
2010-02-09 00:00:00pages
2717-22issue
6eissn
0027-8424issn
1091-6490pii
0907307107journal_volume
107pub_type
临床试验,杂志文章abstract::An experimental scheme for sequencing large DNA molecules is proposed where DNA strands are replicated, with all nucleotides of a given kind marked with radioactive 32P. The marked strands are affixed to an appropriate substrate and are kept until most 32P atoms decay. The local damage caused by the decay is expected ...
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