Dissociating Linguistic and Task-related Activity in the Left Inferior Frontal Gyrus

摘要

The left inferior frontal gyrus (LIFG) has long been claimednto play a key role in language function. However, there is considerablencontroversy as to whether regions within LIFG havenspecific linguistic or domain-general functions. Using fMRI, wencontrasted linguistic and task-related effects by presenting simplenand morphologically complex words while subjects performed anlexical decision (LD) task or passively listened (PL) without makingnan overt response. LIFG Brodmannʼs area 47 showed greaternactivation in LD than PL, whereas LIFG Brodmannʼs area 44nshowed greater activation to complex compared with simplenwords in both tasks. These results dissociate task-driven and obligatorynlanguage processing in LIFG and suggest that PL is thenparadigm of choice for probing the core aspects of the neuralnlanguage system