Temporal Order Processing of Syllables in the Left Parietal Lobe

Abstract

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.

tDCS to temporoparietal cortex during familiarisation enhances the subsequent phonological coherence of nonwords in immediate serial recall

“…There was a clear reduction in the number of phoneme migrations in ISR in both analyses, which was reflected in an increased tendency to recall whole nonwords in position when the familiarisation phase was accompanied by tDCS. We predicted this pattern of effects since the brain region we stimulated is associated with phoneme ordering and phonological learning (Gelfand & Bookheimer, 2003;Cornelissen et al, 2004;Majerus et al, 2005;Graves et al, 2008;Moser et al, 2009). …”

“…Left temporoparietal activity during the repetition of nonwords correlates with phonological-lexical learning and is associated with the retrieval of whole word phonology (Majerus et al, 2005;Graves, Grabowski, Mehta, & Gupta, 2008). Moreover, the left supramarginal gyrus has been specifically linked with the perception (e.g., Jacquemot, Pallier, LeBihan, Dehaene, & Dupoux, 2003;Raizada & Poldrack, 2007;Turkeltaub & Coslett, 2010;Liebenthal, Sabri, Beardsley, Mangalathu-Arumana, & Desai, 2013) and sequencing of phoneme segments (Gelfand & Bookheimer, 2003;Moser, Baker, Sanchez, Rorden, & Fridriksson, 2009). …”

“…Instead, the increased excitability elicited by anodal tDCS (during stimulation; Stagg & Nitsche, 2011) facilitated the acquisition of the phonological forms of the nonwords in long-term memory. This effect is likely to reflect the contributions of a number of neighbouring brain regions supporting aspects of phonological processing, including phonological short-term memory (Warrington & Shallice, 1969;Paulesu, Frith, & Frackowiak, 1993;Jonides et al, 1998;Henson, Burgess, & Frith, 2000;Buchsbaum & Esposito, 2008;Buchsbaum, Padmanabhan, & Berman, 2010;Acheson et al, 2011;Koenigs et al, 2011), phoneme sequencing (Gelfand & Bookheimer, 2003;Moser et al, 2009), translation of auditory to articulatory representations (Hickok & Poeppel, 2000;Papoutsi et al, 2009;Hickok, Houde, & Rong, 2011;Peschke, Ziegler, Eisenberger, & Baumgaertner, 2012), stimulus-driven attention (Downar, Crawley, Mikulis, & Davis, 2001;Ravizza, Hazeltine, Ruiz, & Zhu, 2011;Cabeza, Ciaramelli, & Moscovitch, 2012) and auditory processing for speech (posterior superior temporal cortex).…”

Decoding Articulatory Features from fMRI Responses in Dorsal Speech Regions

“…Specifically, the anterior SMG was found to generalize manner of articulation in the right hemisphere and place of articulation in the left (10 mm searchlight radius) and right (20 mm searchlight radius) hemisphere. Nearby regions involving the inferior parietal lobe (Raizada and Poldrack, 2007;Moser et al, 2009;Kilian-Hü tten et al, 2011) and sylvian-parietaltemporal regions (Caplan and Waters, 1995;Hickok et al, 2003Hickok et al, , 2009Buchsbaum et al, 2011) have been implicated in sensorimotor integration during speech perception as well as in mapping auditory targets of speech sounds before the initiation of speech production Guenther and Vladusich, 2012). Here, we show the sensitivity of SMG to represent articulatory features of spoken syllables during speech perception in the absence of an explicit and active task, such as repetition (Caplan and Waters, 1995;Hickok et al, 2009) or music humming (Hickok et al, 2003).…”

Spasmodic dysphonia and voice tremor: an analysis of the neuropathophysiology, clinical features and treatment options

“…This region is known to be involved in an array of preparatory processes to speech motor execution, including sound categorization, discrimination and phonological decisions on sound content of words (46,47) , processing of syllabic order (48) , semantic retrieval (49,50) , covert articulatory planning and translating speech into articulatory code. (51,52) In our patient cohorts, coupling between functional and structural abnormalities in the IFG may reflect symptomatology of SD and SD/DTv, which is associated with continuous struggles with the choice of words in order to avoid or minimize SD-characteristic voice breaks and to accurately map articulatory planning to speech motor output due to both voice breaks and tremor.…”