Hemispheric lateralization of semantic feature distinctiveness

Abstract

Recent models of semantic memory propose that the semantic representation of concepts is based, in part, on a network of features. In this view, a feature that is distinctive for an object (a zebra has stripes) is processed differently from a feature that is shared across many objects (a zebra has four legs). The goal of this paper is to determine whether there are hemispheric differences in such processing. In a feature verification task, participants responded ‘yes’ or ‘no’ following concepts which were presented to a single visual field (left or right) paired with a shared or distinctive feature. Both hemispheres showed faster reaction times to shared features than to distinctive features, although right hemisphere responses were significantly slower overall and particularly in the processing of distinctive features. These findings support models of semantic processing in which the dominant left hemisphere more efficiently performs highly discriminating ‘fine’ encoding, in contrast to the right hemisphere which performs less discriminating ‘coarse’ encoding.

Distinctive semantic features in the healthy adult brain

“…Second, this effect emerges primarily for natural kinds and is weaker for man-made artifacts. Behaviorally, the results replicate previous findings (Randall, Moss, Rodd, Greer, & Tyler, 2004;Reilly et al, 2015), such that shared features are accessed faster than are distinctive features (this effect was marginally significant in the current results). Furthermore, an interaction emerged between category and feature type.…”

“…There was a weak Category × Feature Type interaction, F(1, 15) = 3.51, p = .08, showing a larger effect for natural kinds compared to artifacts, with slightly higher accuracy for distinctive features than for shared features. For reaction times during accurate trials, a 2 × 2 (Category × Feature Type) ANOVA showed a marginal main effect of feature type, F(1, 15) = 3.72, p = .054, such that shared feature responses were faster than distinctive feature responses (see also Reilly et al, 2015). In addition, an interaction emerged, F(1, 15) = 5.88, p = .015, between category and feature type; the shared feature advantage appears to be driven more strongly by artifacts than by natural kinds.…”

“…Stimuli were based on the set used by Reilly et al (2015). There were 192 concept-feature pairs (e.g., zebra/has stripes vs. zebra/has four legs) selected from the feature norms developed by McRae, Hare, Elman, and Ferretti (2005).…”

“…On the other hand, there is evidence that the right ATL plays a role in semantic processing in nonsocial domains as well Rice, Lambon Ralph, & Hoffman, 2015a). Behaviorally, Reilly, Machado, and Blumstein (2015) showed in a visual half-field study that distinctive features are accessed more slowly than shared features are when a stimulus is presented to either the left or right visual field, suggesting that both hemispheres play a role in detecting distinctive semantic information. Additionally, distinctive features were particularly slow to be accessed by the right hemisphere, consistent with lateralization models that assume the left hemisphere is dominant over the right for processing fine-grained semantic information (Beeman et al, 1994).…”

Fundamentos neurocognitivos del procesamiento lingüístico

“…En el caso del procesamiento léxico-semántico, se ha descrito una red de lateralización izquierda que se extiende en las regiones temporales inferiores posteriores (Kuperberg, McGuire, Bullmore, Brammer, Rabe-Hesketh, Wright, Lythgoe, Williams & David, 2000;Rodd, Davis & Johnsrude, 2005) y superiores, así como en el giro frontal interior (Perani, Cappa, Schnur, Tettamanti, Collina, Miguel Rosa & Fazio, 1999: 2339. La lateralización funcional del procesamiento semántico involucra de manera más eficiente diferentes redes del hemisferio izquierdo, y marca una clara superioridad sobre la participación del hemisferio derecho en la codificación del significado (Reilly, Machado & Blumstein, 2015). En cercanía a la semántica, la lateralización izquierda también define el procesamiento de los estímulos sintácticos, que activan las áreas frontal y temporal (Vigneau et al, 2011), así como las vías dorsal y ventral entre las cortezas frontal y temporal inferiores del hemisferio izquierdo (Friederici, 2012: 262).…”