A Cognitive Neuroscience Examination Of Rhythm And Reading And Their Translation To Neurological Conditions

The goal of the current research was to provide a novel and comprehensive examination of the connection between rhythm and reading through the combination of multiple experimental stimuli, and to translate the reading aloud research to neurological patients. Both speech and music perception/production involve sequences of rhythmic events that unfold over time, and the presence of rhythm in both processes has motivated researchers to consider whether musical and speech rhythm engage shared neural regions (Patel, 2008), and whether musical rhythm can influence speech processing (Cason & Schön, 2012). The experimental paradigm involved examining whether reading aloud is affected by the presentation of a rhythmic prime that was either congruent or incongruent with the syllabic stress of the target letter string. The experiments in Chapter 2 used targets that were words that placed the stress on either the first or second syllable (practice vs. police), as well as their corresponding pseudohomophones (praktis vs. poleese), which allowed us to compare lexical and sublexical reading, respectively. In Chapter 3, the experiments involved a paradigm in which target words have stress on the first syllable for nouns, and on the second syllable for verbs. Thus, the design used identical noun-verb word pairs (conflict vs. conflict), as well as their corresponding pseudohomophones (konflikt vs. konflikt). The results from the behavioural experiments demonstrated that naming reaction times were faster for words and pseudohomophones when the rhythmic prime was congruent with the syllabic stress, and slower when the rhythmic prime was incongruent, which suggests that a rhythmic prime matched to the syllabic stress of a letterstring aids reading processes. Functional magnetic resonance imaging (fMRI) was also used in Chapters 2 and 3 to test whether a network involving the putamen is involved in the effect of rhythm on reading aloud. The fMRI results revealed that a network involving the putamen is associated with the effect of congruency between rhythmic stress and syllabic stress on reading aloud, which is consistent with previous literature that has shown this region is involved in reading, rhythm processing, and predicting upcoming events. Chapter 4 was to provide a behavioural and neuroanatomical examination of reading processes in two patients. Case Study 1 examined the effect of rhythmic priming on reading aloud in a patient with Parkinson’s disease (PD), given that these patients exhibit abnormalities in the putamen, which has been associated with rhythm and reading processes. The patient demonstrated the same behavioural effect as normal participants, whereby individuals benefited from the rhythm prime being congruent with the syllabic stress of the target letter string, and the fMRI results revealed that despite disruptions in basal ganglia functioning following PD, there was still activation in the putamen for reading real words. Case Study 2 examined a patient with intractable left temporal lobe epilepsy (TLE) who was undergoing a temporal lobectomy that involved removing regions of the left temporal lobe that are often thought to be important in language processing. The fMRI results showed that all four reading tasks activated the right posterior occipitotemporal region in the ventral visual stream, confirming the right hemisphere dominance in this patient. Together, these findings have implications for developing neurobiological models of reading, translation to localization of function in neurological conditions such as PD and TLE, and may also reveal potential remedial applications for treating speech deficits in patient populations, such as Parkinson’s disease, stuttering, aphasia, and dyslexia

The Cognitive Chronometric Architecture of Word and Picture Naming: Evidence from Onset Response and Duration

Reading is a fundamental skill for functioning in today’s society. Given the breadth of activities that require reading, it is important to develop a comprehensive model of basic reading processes. Furthermore, considering that many pictures co-appear with words in everyday life, it is imperative to understand the nature of picture identification processes, as well as how they interact with reading processes. As such, the present thesis focuses on developing a model of reading and extending it to include picture processing. In the present research, experiments on word identification (Experiments 1 and 2) examined onset reaction time (RT) in a word naming task using an additive factors method. The pattern of additive and overadditive joint effects on naming RT among Instructions (INST: name all, name words), Word Frequency (WF: log10HAL), Semantic Neighbourhood Density (SND: Inverse Ncount), and Word Type (WT: regular, exception) supported a cognitive chronometric architecture consisting of at least two cascaded stages of processing, with the orthographic lexical system as the locus of the INST x WF and the INST x SND interactions, and the phonological output system as the locus of the WF x WT and the SND x WT interactions. Additivity between INST and WT supports the notion that these variables affect separable systems, and a WF x SND interaction supports a common locus of their effects. These results support a dual-route cascaded model over parallel processing models of basic reading. We also examined response duration (RD) in these data by recording and hand-marking vocal responses, which provides evidence that reading processes are ongoing even after the initiation of a vocal response, and supports the notion that the more lexically a word is read, the shorter the RD. As such, the effects of WT and INST on RD were opposite to their effects on RT. Given the dissociating effects between RT and RD, these results provide new challenges to all models of basic reading processes. Experiments on picture and word identification (Experiments 3 and 4) involved localizing common systems and connections between these processes, and served to extend the dual-route model of reading. These experiments examined naming RT and RD for exception and regular words, and their corresponding pictures. The pattern of joint effects on RT among Format (pictures, words), Picture-Orthography Agreement, WF, and WT (regular, exception) supported a triple-route cascaded model. The results suggest the orthographic lexical system is accessed for both picture and word naming, and demonstrated a dissociation between regular and exception words on RT versus RD, whereas pictures consistently yielded an exception item advantage for both measures. Experiment 4 examined Arabic digits and their corresponding number words, and found that Arabic digits produce shorter RDs than number words. In general, the results suggest that the picture and word identification systems are strongly coupled between the picture memory system and the orthographic lexical system, particularly for items that rely on “whole-word” lexical representations. We argue that RD provides a wider window for exploring cognition, and a converging measure of lexical processing, which must be considered when studying basic identification processes of any stimulus type. The development of a comprehensive model of basic reading processes will help identify behavioural markers of normal reading processes, and will serve to advance research on basic word recognition. In addition, given that a broad definition of ‘literacy’ should include picture processing, the development of a model that includes picture processing will serve to advance research on how reading and picture processing interact with each other, which may be critical for individuals with low literacy skills

A neuroanatomical examination of embodied cognition: semantic generation to action-related stimuli

The theory of embodied cognition postulates that the brain represents semantic knowledge as a function of the interaction between the body and the environment. The goal of our research was to provide a neuroanatomical examination of embodied cognition using action-related pictures and words. We used functional magnetic resonance imaging (fMRI) to examine whether there were shared and/or unique regions of activation between an ecologically valid semantic generation task and a motor task in the parietal-frontocentral network (PFN), as a function of stimulus format (pictures versus words) for two stimulus types (hand and foot). Unlike other methods for neuroimaging analyses involving subtractive logic or conjoint analyses, this method first isolates shared and unique regions of activation within-participants before generating an averaged map. The results demonstrated shared activation between the semantic generation and motor tasks, which was organized somatotopically in the PFN, as well as unique activation for the semantic generation tasks in proximity to the hand or foot motor cortex. We also found unique and shared regions of activation in the PFN as a function of stimulus format (pictures versus words). These results further elucidate embodied cognition in that they show that brain regions activated during actual motor movements were also activated when an individual verbally generates action-related semantic information. Disembodied cognition theories and limitations are also discussed

High Force Unimanual Handgrip Contractions Increase Ipsilateral Sensorimotor Activation and Functional Connectivity

Imaging and brain stimulation studies seem to correct the classical understanding of how brain networks, rather than contralateral focal areas, control the generation of unimanual voluntary force. However, the scaling and hemispheric-specificity of network activation remain less understood. Using fMRI, we examined the effects of parametrically increasing right-handgrip force on activation and functional connectivity among the sensorimotor network bilaterally with 25%, 50%, and 75% maximal voluntary contractions (MVC). High force (75% MVC) unimanual handgrip contractions resulted in greater ipsilateral motor activation and functional connectivity with the contralateral hemisphere compared to a low force 25% MVC condition. The ipsilateral motor cortex activation and network strength correlated with relative handgrip force (% MVC). Increases in unimanual handgrip force resulted in greater ipsilateral sensorimotor activation and greater functional connectivity between hemispheres within the sensorimotor network. (C) 2020 IBRO. Published by Elsevier Ltd. All rights reserved

Examining the neuroanatomical and the behavioural basis of the effect of basic rhythm on reading aloud

<p>We used functional magnetic resonance imaging (fMRI) to examine the brain regions associated with the effect of congruency between rhythmic stress and syllabic stress on reading aloud (Gould et al., 2016). The region of particular interest was the putamen, which has been shown to be involved in speech processing, rhythm processing, and predicting upcoming events. The task involved naming words that placed the stress on either the first or second syllable (practice versus police), as well as their corresponding pseudohomophones (praktis versus poleese) that were preceded by either a congruent or incongruent rhythmic prime. The fMRI results revealed that a network involving the putamen is involved, and the behavioural results demonstrated that a rhythmic prime matched to the syllabic stress aids reading processes of both words and PHs. Implications for neurobiological models of reading, as well as clinical applications (e.g. speech rehabilitation in Parkinson’s disease) are discussed.</p

Presurgical language mapping in epilepsy: Using fMRI of reading to identify functional reorganization in a patient with long-standing temporal lobe epilepsy

We report a 55-year-old, right-handed patient with intractable left temporal lobe epilepsy, who previously had a partial left temporal lobectomy. The patient could talk during seizures, suggesting that he might have language dominance in the right hemisphere. Presurgical fMRI localization of language processing including reading of exception and regular words, pseudohomophones, and dual meaning words confirmed the clinical hypothesis of right language dominance, with only small amounts of activation near the planned surgical resection and, thus, minimal eloquent cortex to avoid during surgery. Postoperatively, the patient was rendered seizure-free without speech deficits

Central Role of Manganese in Regulation of Stress Responses, Physiology, and Metabolism in Streptococcus pneumoniae ▿ †

The importance of Mn2+ for pneumococcal physiology and virulence has been studied extensively. However, the specific cellular role(s) for which Mn2+ is required are yet to be fully elucidated. Here, we analyzed the effect of Mn2+ limitation on the transcriptome and proteome of Streptococcus pneumoniae D39. This was carried out by comparing a deletion mutant lacking the solute binding protein of the high-affinity Mn2+ transporter, pneumococcal surface antigen A (PsaA), with its isogenic wild-type counterpart. We provide clear evidence for the Mn2+-dependent regulation of the expression of oxidative-stress-response enzymes SpxB and Mn2+-SodA and virulence-associated genes pcpA and prtA. We also demonstrate the upregulation of at least one oxidative- and nitrosative-stress-response gene cluster, comprising adhC, nmlR, and czcD, in response to Mn2+ stress. A significant increase in 6-phosphogluconate dehydrogenase activity in the psaA mutant grown under Mn2+-replete conditions and upregulation of an oligopeptide ABC permease (AppDCBA) were also observed. Together, the results of transcriptomic and proteomic analyses provided evidence for Mn2+ having a central role in activating or stimulating enzymes involved in central carbon and general metabolism. Our results also highlight the importance of high-affinity Mn2+ transport by PsaA in pneumococcal competence, physiology, and metabolism and elucidate mechanisms underlying the response to Mn2+ stress

Iris Murdoch and the Ethical Imagination: Legacies and Innovations

Ce numéro d’Études britanniques contemporaines est issu des travaux do colloque de la SEAC organisé par Camille Fort et Marie Laniel en octobre 2019 à l’Université d’Amiens-Jules Verne. Tous nos remerciements s’adressent aux membres des comités d’organisation de ces manifestations ainsi qu’aux chargées d’édition du présent volume. This issue of Études britanniques contemporaines offers a selection of papers given during the SEAC conference convened by Camille Fort and Marie Laniel in October 2019 at the Université d’Amiens-Jules Verne. We would like to express our gratitude to the members of the organising committee and to the guest editors of this volume