Organization of semantic category exemplars in schizophrenia.
Schizophr Res
; 78(2-3): 209-17, 2005 Oct 15.
Article
em En
| MEDLINE
| ID: mdl-16002266
ABSTRACT
Semantic memory was investigated in 27 individuals with schizophrenia and 30 healthy controls using an animal similarity judgment and organization test with reduced retrieval demands. Participants arranged 12 common animal names according to similarity on a computer screen and provided verbal descriptions of organizational strategies. Distance between each animal pair was compared to the number of shared semantic attributes between the pairs (e.g., size, diet, habitat). The three primary organizational strategies included single animals not related to other exemplars, isolated clusters of animals that shared a single strategic relationship (e.g., pets), and overlapping clusters that combined more than one strategic relationship (e.g., cats and mammals). A strong negative correlation was observed between distance ratings and number of shared semantic attributes, confirming that semantic features related to visual distances in both groups. Animal pairs that shared few semantic attributes were placed in closer proximity in the schizophrenia group, whereas the groups placed animal pairs sharing more features equidistantly. Analyses of clustering strategies revealed a double dissociation, with patients relying on isolated, non-overlapping clusters and controls producing more overlapping semantic clusters. Results suggest that performance differences on semantic tasks with limited retrieval demands in schizophrenia relate to difficulties utilizing higher-order categorization strategies.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Esquizofrenia
/
Semântica
/
Transtornos Cognitivos
Tipo de estudo:
Diagnostic_studies
Limite:
Adult
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
Schizophr Res
Assunto da revista:
PSIQUIATRIA
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Estados Unidos