Showing papers by "Mario Liotti published in 2009"
TL;DR: Functional magnetic resonance imaging was used to compare an overt speech task with tongue movement, lip movement, and vowel phonation and showed that the strongest motor activation for speech was the somatotopic larynx area of the motor cortex, thus reflecting the significant contribution of phonation to speech production.
203 citations
TL;DR: It is concluded that frontal ERPs to physical threat words can distinguish the contribution of emotional conflict and emotional salience, particularly in individuals with high trait-anxiety.
69 citations
TL;DR: Evidence that impaired speech production accompanying STN-DBS may result from unintended activation of PMd is provided, and clinical application of functional imaging and TMS may lead to optimizing the delivery of STN -DBS to improve outcomes for speech production as well as general motor abilities.
Abstract: Purpose To explore the use of noninvasive functional imaging and “virtual” lesion techniques to study the neural mechanisms underlying motor speech disorders in Parkinson’s disease. Here, we report...
56 citations
TL;DR: A computational model is presented in which high task motivation modulates proactive pre-stimulus inhibition of the go response, which allows responses to be calibrated so as to fall within a time-window that maximizes the probability of success, regardless of trial type, but does not decrease the observed SSRT.
39 citations
TL;DR: The results provide a close look at some relatively unexplored portions of the temporal flow of information processing in the brain related to the implicit processing of potentially linguistic information and provide valuable information about the interactions between hemispheres supporting visual orthographic processing.
Abstract: The decoding of visually presented line segments into letters, and letters into words, is critical to fluent reading abilities. Here we investigate the temporal dynamics of visual orthographic processes, focusing specifically on right hemisphere contributions and interactions between the hemispheres involved in the implicit processing of visually presented words, consonants, false fonts, and symbolic strings. High-density EEG was recorded while participants detected infrequent, simple, perceptual targets (dot strings) embedded amongst a of character strings. Beginning at 130ms, orthographic and non-orthographic stimuli were distinguished by a sequence of ERP effects over occipital recording sites. These early latency occipital effects were dominated by enhanced right-sided negative-polarity activation for non-orthographic stimuli that peaked at around 180ms. This right-sided effect was followed by bilateral positive occipital activity for false-fonts, but not symbol strings. Moreover the size of components of this later positive occipital wave was inversely correlated with the right-sided ROcc180 wave, suggesting that subjects who had larger early right-sided activation for non-orthographic stimuli had less need for more extended bilateral (e.g. interhemispheric) processing of those stimuli shortly later. Additional early (130-150ms) negative-polarity activity over left occipital cortex and longer-latency centrally distributed responses (>300ms) were present, likely reflecting implicit activation of the previously reported ‘visual-word-form’ area and N400-related responses, respectively. Collectively, these results provide a close look at some relatively unexplored portions of the temporal flow of information processing in the brain related to the implicit processing of potentially linguistic information and provide valuable information about the interactions between hemispheres supporting visual orthographic processing.
35 citations