Semantic factors of entity retrieval in Greek aphasia: evidence from category and size
Eleni Karka
National and Kapodistrian University of Athens
The Sensory/Functional theory has been used in neuropsychology to explain the category-specificity of semantic memory. It assumes that the identification of living entitiesdifferentially depends on visual/perceptual knowledge, while the ability to recognizenonliving entities depends on functional/associative knowledge. This research aims atthe identification of semantic factors that may influence entity retrieval from the semanticmemory of Greek aphasic patients.Primary data were obtained by the Eginition Hospital in Athens. Thirty-five aphasic patientswho have suffered cerebrovascular accident undergo the “Boston Naming Test”and the “Snodgrass & Vanderwart” naming test. A corpus of verbatim intermediate er36ror responses produced by patients while they search for the elusive word was developed.Research assumptions divided into those based on the category (living vs. nonlivingentities) and those based on the size (large vs. small entities) were formulated.Results indicate that research assumptions based on the category are in accordancewith the Sensory/Functional theory, that is, living entities tend to be distinguished moreeasily on the basis of their sensory features (camel ΰ this animal has two humps) whilenonliving entities on the basis of their functional features (racket ΰ tennis). The size ofentities, however, plays an important role as regards the mechanism of entity retrieval.Living entities, independently of their size, are retrieved by patients with similar in sizeliving entities (beaver ΰ little bear). As for large nonliving entities, it is observed thatthere is a particular subset of the sensory features that seems to influence their retrieval (house ΰ door).In conclusion, size seems to be a hyper-category feature that affects both living andnonliving entities. In general, there is no universal mechanism of entity retrieval basedon the category to which an entity belongs.
