Authors:

BOZIC, M., MARSLEN-WILSON, W.D., Tyler, L.K

Reference:

Year of publication:

2005

CBU number:

6490

Abstract:

Neuroimaging studies of morphological processing implicate the Left Inferior Frontal Gyrus (LIFG) in processing inflected [e.g. jump-jumped] and derived [e.g. happy-happiness] words, suggesting that the LIFG supports morphological analysis processes. In a recent efMRI study we showed that LIFG effects occur whether the meaning of a complex word is compositional [e.g. bravely-brave] or not [e.g. archer-arch], leaving open the question of what specifically drives decomposition. In the present efMRI study we ask whether morphological analysis is triggered by the apparent surface compositionality of complex words, as reflected in the productivity of the derivational suffixes employed. The more productive a suffix, the more likely that the complex form is decompositionally represented. We compared priming for derived/stem pairs with productive suffixes [swimmer-swim] and unproductive suffixes [warmth/warm], as well as for three control conditions (identity, [e.g. quest-quest], form overlap only [e.g. antique-ant], and meaning overlap only [e.g. accuse-blame]). Participants performed a lexical decision task (SOA=2.5 sec) in a delayed repetition paradigm with on average 18 intervening items between prime/target pairs. EPI images were acquired using a 3T Bruker scanner (TR=1.1 secs). We found, once again, LIFG activation for morphologically complex words, compared to words which overlap in either form or meaning. Moreover, LIFG activation was modulated by morphological productivity. Words with unproductive suffixes generated the strongest priming effect, reflecting the sensitivity of the system to linguistic variables.