RT Journal Article
SR Electronic
T1 Temporal Order Processing of Syllables in the Left Parietal Lobe
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 12568
OP 12573
DO 10.1523/JNEUROSCI.5934-08.2009
VO 29
IS 40
A1 Dana Moser
A1 Julie M. Baker
A1 Carmen E. Sanchez
A1 Chris Rorden
A1 Julius Fridriksson
YR 2009
UL http://www.jneurosci.org/content/29/40/12568.abstract
AB Speech processing requires the temporal parsing of syllable order. Individuals suffering from posterior left hemisphere brain injury often exhibit temporal processing deficits as well as language deficits. Although the right posterior inferior parietal lobe has been implicated in temporal order judgments (TOJs) of visual information, there is limited evidence to support the role of the left inferior parietal lobe (IPL) in processing syllable order. The purpose of this study was to examine whether the left inferior parietal lobe is recruited during temporal order judgments of speech stimuli. Functional magnetic resonance imaging data were collected on 14 normal participants while they completed the following forced-choice tasks: (1) syllable order of multisyllabic pseudowords, (2) syllable identification of single syllables, and (3) gender identification of both multisyllabic and monosyllabic speech stimuli. Results revealed increased neural recruitment in the left inferior parietal lobe when participants made judgments about syllable order compared with both syllable identification and gender identification. These findings suggest that the left inferior parietal lobe plays an important role in processing syllable order and support the hypothesized role of this region as an interface between auditory speech and the articulatory code. Furthermore, a breakdown in this interface may explain some components of the speech deficits observed after posterior damage to the left hemisphere.