Close, but no garlic: Perceptuomotor and event knowledge activation during language comprehension

Abstract

Recent research has shown that language comprehension is guided by knowledge about the organization of objects and events in long-term memory. We use event-related brain potentials (ERPs) to determine the extent to which perceptuomotor object knowledge and event knowledge are immediately activated during incremental language processing. Event-related but anomalous sentence continuations preceded by single-sentence event descriptions elicited reduced N400s, despite their poor fit within local sentence contexts. Anomalous words sharing particular sensory or motor attributes with contextually expected words also elicited reduced N400s, despite being inconsistent with global context (i.e., event information). We rule out plausibility as an explanation for both relatedness effects. We show that perceptuomotor-related facilitation is not due to lexical priming between words in the local context and the target or to associative or categorical relationships between expected and unexpected targets. Overall our results are consistent with the immediate and incremental activation of perceptual and motor object knowledge and generalized event knowledge during sentence processing.

Figure 1

Schematic showing the 26 channel array of scalp electrodes from which the EEG was recorded.

Figure 2

ERPs to perceptuomotor-related continuations are shown alongside ERPs to expected targets and unrelated continuations. The perceptuomotor-related N400 reduction is clearly visible at several centro-parietal sites.

Figure 3

ERPs to event-related continuations are shown alongside ERPs to expected targets and unrelated continuations. The event-related N400 reduction is clearly visible at several centro-parietal sites.

Figure 4

ERPs for plausibility-matched anomalies. (A) Grand averaged ERPs at four midline (anterior to posterior) sites show the reduced N400s for the event-related and perceptuomotor-related conditions in comparison with the unrelated condition. (B) Grand averaged difference ERPs at the same four sites show the N400 facilitation effects. The 300 to 500 ms time window employed in statistical analyses is shaded in both panels.