The neural correlates of picture naming facilitated by auditory repetition

The behavioral results showed that both short- and long-term facilitated items were named significantly faster than unfacilitated items, with short-term items significantly faster than long-term items. Neuroimaging analyses identified a repetition suppression effect for long-term facilitated items, relative to short-term facilitated and unfacilitated items, in regions known to be associated with both semantic and phonological processing. A repetition suppression effect was also observed for short-term facilitated items when compared to unfacilitated items in a region of the inferior temporal lobe linked to semantic processing and object recognition, and a repetition enhancement effect when compared to long-term facilitated items in a posterior superior temporal region associated with phonological processing.These findings suggest that different neurocognitive mechanisms underlie short- and long-term facilitation of picture naming by an auditory repetition task, reflecting both phonological and semantic processing. More specifically, the brain areas engaged were consistent with the view that long-term facilitation may be driven by a strengthening of semantic-phonological connections. Short-term facilitation, however, appears to result in more efficient semantic processing and/or object recognition, possibly in conjunction with active recognition of the phonological form.Word retrieval is often targeted clinically in the treatment of individuals suffering from the naming difficulties associated with post-stroke aphasia. One common form of word retrieval treatment involves repeating a target name in the presence of the target picture. This task is often framed as a phonological treatment and is assumed by some to improve word retrieval by targeting phonological representations. However, such a task may also improve word retrieval by increased semantic activation or strengthening of mappings between semantics and phonology [1]. The neural mechanisms underpinning such ef