Exploring orthographic neighborhood size effects in a computational model of Chinese character naming

- Effects of orthographic neighborhood size in Chinese character naming were examined.
- Inconsistent characters with large neighborhood size inhibited the naming latencies.
- Two PDP models of Chinese character naming were developed to explore the effect.
- Consistency and neighborhood size interact with the division of labor in the system.
- The semantic pathway contributes to the inhibitory effect of neighborhood size.

Orthographic neighborhood (N) size effects have been extensively studied in English consistently producing a facilitatory effect in word naming tasks. In contrast, several recent studies on Chinese character naming have demonstrated an inhibitory effect of neighborhood size. Response latencies tend to be inhibited by inconsistent characters with large neighborhoods relative to small neighborhoods. These differences in neighborhood effects between languages may depend on the characteristics (depth) of the mapping between orthography and phonology. To explore this, we first conducted a behavioral experiment to investigate the relationship between neighborhood size, consistency and reading response. The results showed an inhibitory effect of neighborhood size for inconsistent characters but a facilitatory effect for consistent characters. We then developed two computational models based on parallel distributed processing principles to try and capture the nature of the processing that leads to these results in Chinese character naming. Simulations using models based on the triangle model of reading indicated that consistency and neighborhood size interact with the division of labor between semantics and phonology to produce these effects.