Dissertations / Theses on the topic 'Dorsolateral prefrontal cortex'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 48 dissertations / theses for your research on the topic 'Dorsolateral prefrontal cortex.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Greenberg, Paul Arthur. "Functional Stability and Learning in the Dorsolateral Prefrontal Cortex." Diss., Tucson, Arizona : University of Arizona, 2005. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1030%5F1%5Fm.pdf&type=application/pdf.
Full textLanoue, Amelie Cecile. "Neuropathology in the dorsolateral prefrontal cortex in Parkinson's disease." Thesis, Boston University, 2013. https://hdl.handle.net/2144/11112.
Full textDegeneration of dopaminergic neurons in the substantia nigra pars compacta is the hallmark neuropathological feature of Parkinson's disease (PD). Multiple lines of evidence from anatomical and imaging studies indicate that cell loss or cell dysfunction also occur in other brain regions. The dorsolateral prefrontal cortex (DLPFC) is a region of interest because it could be implicated in both cognitive and motor symptoms of PD. However, studies in this brain region are limited and the extent of pathology is unclear. Work in this thesis was aimed at identifying possible neuropathology in post-mortem PD tissue from Brodmann area 9 (BA9), a region of the DLPFC. In the first study, using design-based stereology and radioisotopic in situ hybridization histochemistry (ISHH), we found that expression of two mitochondrial genes, NDUFS1 and COX1, was not altered and that no global loss of neurons occurs in BA9 in PD. In a second study, using ISHH and gene expression microarray analysis (One-Color Agilent 60-mer Whole Human Genome Microarray), we found decreased gene expression of the GABA-synthesizing enzyme glutamic acid decarboxylase (GAD67) in BA9 in PD, an effect that was not paralleled by a decrease in the numbers of GAD67 mRNA-expressing neurons. In a third study, using ISHH, we found that gene expression of the calcium-binding protein parvalbumin, which is selectively expressed in a subset of cortical GABAergic interneurons, is decreased in BA9 in PD. However, we found no loss of immunolabeled parvalbumin-positive neurons in BA9 in PD. In summary, the results indicate that expression of two key markers of GABAergic activity, GAD67 and parvalbumin, is depressed in BA9 in PD and that these effects are not due to a loss of neurons. This suggests that GABAergic neurotransmission is deficient in the DLPFC in PD and we propose that treatments aimed at restoring GABAergic inhibition in BA9 would have therapeutic efficacy in the symptomatic treatment of PD.
Fernandes, Ninette M. "The Detection of Prefrontal Cortex Development into Early Adulthood." Marietta College / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=marietta1164924291.
Full textKeifer, Ekaterina. "Performance of patients with ventromedial prefrontal, dorsolateral prefrontal, and non-frontal lesions on the Delis-Kaplan Executive Function System." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/830.
Full textNord, Camilla Laxmi. "The role of dorsolateral prefrontal cortex dysfunction in depression and its treatment with non-invasive brain stimulation." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/10038161/.
Full textPlakke, Anderson Bethany Joy. "Auditory working memory: contributions of lateral prefrontal cortex and acetylcholine in non-human primates." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/1060.
Full textMiléa, Dan. "Le lobe frontal dans le contrôle de la motricité oculaire." Paris 6, 2003. http://www.theses.fr/2003PA066225.
Full textBrooks, Samantha J., Jonathan Cedernaes, and Helgi B. Schiöth. "Increased prefrontal and parahippocampal activation with reduced dorsolateral prefrontal and insular cortex activation to food images in obesity : a meta-analysis of fMRI studies." Uppsala universitet, Funktionell farmakologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-199757.
Full textHawco, Colin Shaun. "The role of the dorsolateral prefrontal cortex in self-initiating elaborative episodic encoding: evidence from fMRI and TMS." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114200.
Full textPlusieurs populations cliniques (ex. schizophrénie, maladie d'Alzheimer, lésions du lobe frontal, vieillissement normal avec déclin de mémoire) démontrent des déficits de mémoire qui peuvent être reliés à une incapacité d'initier des stratégies efficaces d'encodage de mémoire. Cependant, ces groupes démontrent souvent une amélioration de leur performance lorsqu'on les aide à choisir une stratégie d'encodage efficace, suggérant que les déficits seraient reliés à l'utilisation spontanée de stratégies d'encodage élaborées. A ce jour, nous savons très peu de choses à propos des corrélats neuronaux de l'utilisation spontanée de stratégies d'encodage élaborées. Le but de cette thèse est de mieux comprendre les processus de l'initiation de stratégies d'encodage élaborées. Nous émettons l'hypothèse que le cortex préfrontal dorsolatéral (DLPFC) est impliqué dans l'utilisation spontanée de stratégies d'encodage élaborées. L'expérience 1 consiste en une étude d'IRMf dans laquelle nous avons présenté des conditions dans lesquelles les participants étaient guidés à utiliser une stratégie d'encodage efficace (analyse sémantique) ou non guidés d'utiliser cette stratégie (condition auto-initiée), en présentant des stimuli de relations sémantiques variées. Nous avons observé une activité dans le DLPFC gauche et le gyrus supramarginal bilatéral en réponse à la relation sémantique dans la condition d'encodage non-sémantique (auto-initiée). Dans l'expérience 2, nous avons tenté de confirmer le rôle du DLPFC gauche dans l'utilisation spontanée de stratégies d'encodage élaborées en utilisant la stimulation magnétique transcrânienne (SMT), une méthode avec laquelle nous pouvons perturber l'activité neuronale de façon transitoire dans une aire corticale limitée. Nous avons performé une stimulation du DLPFC gauche et d'un site contrôle (le vertex) durant une tâche d'encodage de mémoire. Nous avons observé une corrélation significative dans la tâche de reconnaissance subséquente (une mesure de la réussite de l'encodage) entre les effets de la SMT durant l'encodage et l'utilisation de stratégies de mémoire du participant pendant l'encodage seulement dans la condition où l'utilisation spontanée de stratégies d'encodage élaborées était bénéfique pour la performance de mémoire. Ceci suggère un rôle causal du DLPFC dans l'utilisation spontanée de stratégies d'encodage élaborées. L'expérience 3 était une étude simultanée de SMT-IRMf. Les participants devaient faire une tâche d'encodage (similaire à la condition auto-initiée de l'expérience 1) pendant que l'on mesurait l'activité du cerveau avec l'IRMf. Une SMT était faite pendant 300ms sur les trois-quarts des essais. Le début de la stimulation était varié, commençant à 200ms, 600ms ou 1000ms après le début du stimulus. Nous avons observé des changements spécifiques au temps dans l'activité neuronale en réponse à la stimulation SMT, indiquant que l'utilisation simultanée de SMT-IRMf peut être utilisée pour mesurer l'interaction en fonction du temps entre le DLPFC et les régions distales du cerveau. Ces trois expériences apportent des évidences du rôle du DLPFC gauche dans l'utilisation spontanée de stratégies d'encodage élaborées et l'utilité de la SMT et de l'IRMf (séparément ou combinées) comme techniques de recherche pour étudier ces processus. Ces études démontrent aussi l'utilité de nos paradigmes pour étudier directement l'utilisation spontanée de stratégies d'encodage élaborées (au lieu de corréler l'activité à des stratégies d'encodage spécifique).
Bunch, Katie, and n/a. "A Relational Complexity Approach to the Development of Hot/Cool Executive Functions." Griffith University. School of Psychology, 2006. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20070713.121052.
Full textBunch, Katie. "A Relational Complexity Approach to the Development of Hot/Cool Executive Functions." Thesis, Griffith University, 2006. http://hdl.handle.net/10072/367631.
Full textThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Psychology
Full Text
Shaw, Lynda Joan. "Emotional processing of natural visual images in brief exposures and compound stimuli : fMRI and behavioural studies." Thesis, Brunel University, 2009. http://bura.brunel.ac.uk/handle/2438/3203.
Full textRosero, Pahi Mario Alberto [Verfasser], and Herta [Akademischer Betreuer] Flor. "The role of the hippocampus and dorsolateral prefrontal cortex in implicit learning of contextual information / Mario Alberto Rosero Pahi ; Betreuer: Herta Flor." Heidelberg : Universitätsbibliothek Heidelberg, 2019. http://d-nb.info/1187342149/34.
Full textHeinze-Köhler, Katharina [Verfasser], and Markus [Akademischer Betreuer] Heinrichs. "The role of left and right mid-dorsolateral prefrontal cortexin planning: a brain stimulation approach = Die Bedeutung des linken und rechten mittleren dorsolateralen präfrontalen Cortex für Planungsprozesse: Untersuchungen mit Gehirnstimulationsverfahren." Freiburg : Universität, 2014. http://d-nb.info/1123481679/34.
Full textAraujo, Ricardo Rafael de. "Modulação da orientação temporal e espacial da atenção por meio de estimulação transcraniana por corrente contínua." Universidade Presbiteriana Mackenzie, 2011. http://tede.mackenzie.br/jspui/handle/tede/1548.
Full textFundo Mackenzie de Pesquisa
Attention can be understood as a set of neural mechanisms that enhance the processing of relevant information, thoughts or actions while ignoring irrelevant or scattered stimuli. Thus, attention allows the organism to interact in a proper way with the environment. Among the brain structures associated with the control of attention, the Dorsolateral Prefrontal Cortex (DLPFC) has a remarkable role in current literature as a region associated with behavioral control. Transcranial Direct Current Stimulation (TDCS) is based on the application of a low intensity electric current through electrodes placed in the scalp, aimed at modulating the activity of different brain areas. This technique has been used to study brain functions. This study has the objective of verifying how attention can be modulated through the application of bilateral tDCS on DLPFC using measures of reaction time (RT) in tasks of temporal and spatial orientation. To accomplish that, two experiments were planned and executed. In the first one, which focused on the voluntary orienting of spatial attention, each participant had to orient attention to the position indicated by an arrow; in the second, on voluntary orienting of temporal attention, each participant had to orient attention to the most frequent time interval of visual targets. In both cases, participants had to respond as fast as possible when the target was displayed by pressing a joystick key. RTs were registered. The sample was composed of 18 undergraduate students, age range 19-25 years old (12 for the first experiment and 6 more for the second). In each experiment, subjects were submitted to three tDCS conditions (anodal, cathodal and sham) on the DLPFC during the undertaking of tests. Analyses of variance were made, in order to compare the involved factors. For the experiment of spatial orientation, the anodal condition produced lower RTs, when compared to sham. For the temporal orienting experiment it was observed that, in the anodal modulation, RTs were increased for the less frequent interval (500 ms), indicating that the anodal tDCS can have influenced in a more effective way attentional orienting to the most frequent intervals. Therefore it is possible to postulate the existence of a facilitating effect of anodal tDCS in the modulation of DLPFC, which generated an impact in attentional orienting, lowering RTs to the valid condition (spatial) when compared to sham tDCS.
A atenção pode ser compreendida como um conjunto de mecanismos neurais que facilitam o processamento de informações, pensamentos ou ações relevantes enquanto ignoram outros irrelevantes ou dispersos. Deste modo a atenção permite que o organismo interaja de maneira adequada com o ambiente. Dentre as estruturas cerebrais associados ao controle da atenção, o Córtex Prefrontal Dorsolateral (CPFDL) tem tomado papel de destaque na literatura atual como uma região associada ao controle comportamental. A Estimulação Transcraniana por Corrente Contínua (ETCC) se baseia na aplicação de corrente elétrica de baixa intensidade por meio de eletrodos posicionados no escalpe com o objetivo de modular a atividade de diferentes regiões cerebrais e tem sido utilizada como modo de estudo da função cerebral. Esse trabalho tem como objetivo verificar como a atenção pode ser modulada a partir da aplicação ETCC bilateral sobre o CPFDL, utilizando medidas de tempo de reação (TR) em tarefas de orientação temporal e espacial. Para Tanto foram planejados e executados dois experimentos. No primeiro experimento, relativo à orientação voluntária da atenção espacial, cada participante deveria orientar a atenção para a posição do espaço indicada por uma seta. O segundo experimento, relativo à orientação voluntária da atenção temporal, cada participante deveria orientar a atenção para o intervalo temporal de maior recorrência. Em ambos os casos os participantes deveriam responder o mais rapidamente possível ao aparecimento do alvo pressionado uma tecla de joystick registrando-se assim o seu TR. Participaram desse estudo 18 alunos de graduação (12 no primeiro desenho experimental, e para o segundo desenho experimental foram adicionados mais 6 colaboradores) na faixa etária de 19 à 25 anos. A cada sessão os colaboradores deveriam responder a ambos os experimento enquanto eram submetidos a diferentes polaridades de ETCC (anódica, catódica e placebo) sobre o CPFDL. Foram feitas análises de variância para comparar os fatores estudados. No experimento de orientação espacial a condição anódica produziu TR menores em comparação à condição placebo. No caso do experimento de orientação temporal foi observado que na modulação anódica houve um aumento nos TR no intervalo menos recorrente de 500 ms, indicando que a ETCC anódica pode ter influenciado de modo mais efetivo o direcionamento atencional aos intervalos mais freqüentes. Neste sentido é possível sugerir a existência de um efeito facilitatório da ETCC anódica na moducalçao do CPFDL, o que gerou um impacto no direcionamento atencional, diminuindo os TR para a condição valida (orientação espacial) quando comparados a ETCC placebo.
Mell, Thomas, Isabell Wartenburger, Alexander Marschner, Arno Villringer, Friedel M. Reischies, and Hauke R. Heekeren. "Altered function of ventral striatum during reward-based decision making in old age." Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2010/4523/.
Full textLindberg, Markus. "Neural correlates of lucid dreaming and comparisons with phenomenological aspects." Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-10236.
Full textGold, Brian T. "The human dorsolateral prefrontal cortex a critical neural module in the transformation of information within working memory : evidence from fMRI of deductive reasoning at 4 T /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0027/NQ39266.pdf.
Full textBraasch, Marie Y. "The Effects of Age and Working Memory Ability on Frontal Lobe Oxygenation During Working Memory Tasks." Ohio University Honors Tutorial College / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1275937579.
Full textWohlwend, Martin. "Investigation of an Exercise-Induced State of Hypofrontality : And its Potential Association with Central Fatigue." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for nevromedisin, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16840.
Full textPsomiades, Marion. "Altérations cérébrales structurales et fonctionnelles spécifiques des hallucinations auditives résistantes chez les patients atteints de schizophrénie." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1218.
Full textAuditory hallucinations (AH) are present in 70% to 80% of patients with schizophrenia and are resistant to pharmacological treatments in 25% of cases. These symptoms induce significant distress in patients and predict a bad prognosis. In this work we have highlighted cerebral alterations specific to AH in patients suffer from schizophrenia. In a first study, using DTI method, we showed that patients with schizophrenia and AH have an arcuate fasciculus integrity, reflected by the measurement of fractional anisotropy (FA) greater than the one measured in patients with schizophrenia without AH. In a second study, using MRS method, we showed an increase of NAA level measured in the dorsolateral prefrontal cortex (DLPFC) in the right hemisphere in patients with schizophrenia and AH compared to the DLPFC in the left hemisphere and compared to patients with schizophrenia and without AH. Moreover, in these two studies we showed an association between AH severity and the arcuate fasciculus integrity in the left hemisphere and an association between AH severity and NAA levels in the right DLPFC. Finally, in our last study, we quantified BDNF levels using ELISA method and showed an association between peripheral BDNF level, a marker of neuronal plasticity, and NAA levels in the right DLPFC, marker of neuronal metabolism, in patients with treatment-resistant schizophrenia. These results show that there is a specific pathophysiology of AH in patients with schizophrenia and highlight the importance of stratifying patients on the basis of their predominant symptoms in future pathophysiological studies of schizophrenia
Caetano, Sheila Cavalcante. ""Avaliação volumétrica e neuroquímica do córtex pré-frontal dorsolateral esquerdo de pacientes pediátricos com transtorno depressivo maior: um estudo utilizando espectroscopia por ressonância magnética de próton"." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/5/5142/tde-18042006-144855/.
Full textMagnetic resonance imaging and proton magnetic resonance spectroscopy have been applied to anatomical and neurochemical studies of Major Depressive Disorder (MDD). Nineteen children with MDD and 24 healthy controls were evaluated on a 1.5 Tesla (Philips Intera 8.1.1.) MRI. Compared to healthy controls, children with MDD presented: smaller left hippocampal volumes; and lower levels of choline-containing-compounds and higher myo-inositol levels in the left DLPFC. Lower levels of choline-containing-compounds in pediatric patients with MDD may reflect lower cell membrane turn-over. Higher myo-inositol levels in MDD may represent a disturbed secondary messengers system
Oliveira, Rogério Adas Ayres de. "O efeito da estimulação magnética transcraniana repetitiva do córtex pré-frontal dorsolateral esquerdo na dor central decorrente de acidente vascular cerebral." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/5/5138/tde-10032017-085905/.
Full textIntroduction and objectives: Central post-stroke pain (CPSP) is caused by an encephalic vascular lesion of the somatosensory pathways and is refractory to current pharmacological treatments. Repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex (DLPFC) can change thermal pain threshold and cause analgesia in healthy subjects and also in acute post operatory pain as well as in fibromyalgia patients. However, its effect on neuropathic pain and particularly in CPSP patients has not been assessed yet. The aim of this prospective, double blind, shamcontrolled study was to evaluate the analgesic effect of left DLPFC rTMS in CPSP patients. Patients and methods: 21 patients were randomly included in two groups: the active (A-rTMS) group and the placebo (S-rTMS) group and were treated, respectively, with 10 daily sessions of real rTMS (A-rTMS) or sham (S-rTMS) of the left DLPFC (10 Hz, 1250 pulses/day). Visual Analogue Scale (VAS), Neuropathic Pain Questionnaire and McGill Pain Questionnaire were used to evaluate the CPSP. The depression, the anxiety and the quality of life were evaluated, respectively, with the Hamilton Scale for Depression, Hamilton Scale for anxiety and the Short Form Health Survey with 36 items. Outcomes were assessed at the baseline, during the stimulation phase and at one, two and four weeks after the last session of ArTMS or S-rTMS. The main outcome was pain intensity change measured with the VAS at the last session of A-rTMS or S-rTMS, compared to the baseline. Interim analysis was scheduled when the first half of the patients have completed the study. Results: The average baseline scores of VAS were 6.86 (+/- 1.79) and 6.8 (+/- 2.20), respectively, for the groups A-rTMS and S-rTMS. The average variation of VAS after the 10th stimulation session was - 0.07 (+/- 0.24) for A-rTMS and 0.1 (+/- 0.7) to the S-rTMS group and the effect size of A-EMTr was 0.02 (Cohen\'s d= 0.04). The study was discontinued due to the significant lack of efficacy of the A-rTMS. Conclusion: Repetitive transcranial magnetic stimulation of the left DLPFC did not provide an analgesic effect in CPSP patients
Nery, Fabiano Gonçalves. "Estudo do córtex pré-frontal dorsolateral esquerdo de pacientes portadores de transtorno afetivo bipolar em comorbidade com alcoolismo através do uso de espectroscopia por ressonância magnética de hidrogênio." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5142/tde-31082009-153516/.
Full textAbout 50% of bipolar disorder (BD) patients present comorbidity with alcohol abuse or dependence. The presence of alcoholism in BD is associated with worse clínical manifestations and refractoriness to treatment of the mood disorder. Nevertheless, the neurochemical underpinnings that underlie the co-occurrence of bipolar disorder and alcoholism are unknown. In this study, we sought to compare the neurochemical profile of the left dorsolateral pre-frontal cortex of BD patients with a prior diagnosis of alcoholism to non-alcoholic BD patients and healthy controls (HC), using proton (1H) magnetic resonance spectroscopy. We obtained a short-TE, single-voxel 1H spectroscopy acquisition at 1.5 Tesla from the left dorsolateral pré-frontal córtex (DLFPC) of 23 alcoholic BD patients, 27 non-alcoholic BD patients and 57 HC. Absolute levels of N-acetyl-aspartate (NAA), choline-containing compounds, phosphocreatine plus creatine, myo-inositol, glutamato plus glutamina (Glu+Gln) and glutamato were determined and compared among the three groups. Alcoholic BD patients showed lower Glu+Gln (p = 0.06) and glutamate levels (p = 0.03) than non-alcoholic BD patients. Alcoholic BD patients tended to have lower NAA levels than HC (p = 0.06). These findings suggest that glutamatergic abnormalities, and possibly, neuronal integrity abnormalities, are present in the left DLPFC of BD patients with comorbid alcoholism. Such abnormalities may characterize pathophysiological processes that are specific for the comorbidity between BD and alcoholism.
Rosa, Carlos Eduardo. "Disfunção neuroquímica na depressão periparto." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/17/17138/tde-27072016-151947/.
Full textPeripartum depression (PPD) is a highly prevalent subtype of major depressive disorder (MDD) related to a significant loss for mother, family and baby. An Interaction between hormones, genetic, and environmental factors must be involved in its etiology. However, neuroimaging studies on PPD are still rare, particularly those that identify neurochemical changes. However, neuroimaging studies in PPD are still rare, particularly those that identify neurochemical changes. It is known that the region of the dorsolateral prefrontal cortex (dlPFC) is related to executive functions in the prefrontal circuit, and together with the anterior cingulate gyrus (ACG) is part of the neural pathways involved in emotional processing, including the generation, regulation, and reappraisal of affective state. And, there is evidence that both areas are dysfunctional in MDD. The neurochemical evaluation obtained by spectroscopy of proton magnetic resonance (MRS) allows to infer metabolism, neurotransmission and the viability of the neuronal tissue of interest these frontal-limbic areas. Objective: Compare postpartum women with peripartum depression (PPD group) with healthy postpartum women (HP group) regarding the neurochemical evaluation in the left dlPFC and bilateral ACG. Methods: 36 postpartum women of PPD group and 25 postpartum women of the HP group were subjected to two structured psychiatric interviews and questionnaires and psychometric scales, with the second evaluation performed sectionally at MRS. The MRS was obtained by 3-T MRI system with the volume of interest (VOI) positioned on the left dlPFC and bilateral ACG and processed by LC Model software. The neurochemical results expressed in absolute values and normalized by creatine (reason metabolite/creatine) were analyzed using ANCOVA, including age, postpartum time, the type of contraceptive as covariates. Results: In the dlPFC, PPD group presented significantly lower values of Glu/Cr (-0.17; p=0.05), Glx (-0.95mM; p=0.04), Glx/Cr (-0.22; p=0.03), NAA (-0.60mM; p<0.01), and NAA/Cr (-0.13; p=0.02) than HP. In ACG, progestogens isolated contraceptive hormones use resulted in significantly increased Glu (2.18mM; p=0.03), Glx (1.84mM; p=0.03), and reduced Cho/Cr (-0.08; p=0.03), compared to women without use them, regardless of diagnostic groups. Conclusions: The reduced levels of Glu and NAA in the PPD group are related respectively to the glutamatergic and neuroglial metabolic dysfunction in the dlPFC, which may explain cognitive symptoms also related to PPD as already verified in MDD. Progestogens isolated contraceptive hormones use interfered with neurochemistry of ACG, but not associated with PPD. Although the increase of glutamate may suggest an overactive ACG, and lower Cho/Cr represent decrease of the lipid membrane turnover or synaptic transduction its clinical and pathophysiological significance remains uncertain. These results contribute to the understanding of the neurochemical substrates of PPD
Junior, Claudinei Eduardo Biazoli. "Inferência do tempo de atividade neural a partir do efeito BOLD em ressonância magnética funcional." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/5/5151/tde-20072011-170109/.
Full textThe extraction of information about neural activity dynamics related to the BOLD signal is a challenging task. The temporal evolution of the BOLD signal does not directly reflect the temporal characteristics of electrical activity of neurons. In this work, we introduce the concept of neural processing time (NPT) as a parameter of the biophysical model of the hemodynamic response function (HRF). Through this new concept we aim to infer more accurately the duration of neuronal response from the highly nonlinear BOLD effect. We describe two routines to estimate the parameters of the HRF model. The face validity and applicability of the concept of NPT and the estimation procedures are evaluated through simulations and analysis of experimental time series. The results of both simulation and application were compared with summary measures of HRF shape. We analysed an experiment based on a decision-making paradigm with simultaneous emotional distracters. We hypothesize that the NPT in primary sensory areas is approximately the stimulus presentation duration. On the other hand, the NPT in brain areas related to decisionmaking processes should be less than the stimulus duration. Moreover, in areas related to processing of an emotional distracter, the NPT should depend on the experimental condition. As predicted, the NPT in fusiform gyrus is close to the stimulus duration and the NPT in dorsal anterior cingulate gyrus depends on the presence of an emotional distracter. Interestingly, the estimated NPTs in the dorsolateral prefrontal cortex indicate functional laterality of this region. The analysis using standard measures of HRF did not detect the variations observed in our method (NPT)
Kaufman-Simpkins, Liam. "Antisaccades: A Probe into the Dorsolateral Prefrontal Cortex in Alzheimer's Disease." Thesis, 2008. http://hdl.handle.net/1807/17185.
Full textChiang, Yung-Tai, and 江詠泰. "Using Repetitive Transcranial Magnetic Stiulation at Dorsolateral Prefrontal Cortex to Explore the effect of Pain Threshold." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/3665hq.
Full text國立陽明大學
醫學工程研究所
102
In this thesis work, we compared the analgesic effects of high-frequency (10 Hz) repetitive Transcranial Magnetic Stimulation (rTMS) applied to the primary motor cortex (M1) and the dorsolateral prefrontal cortex (DLPFC) respectively. Pain sensation was elicited by direct-current (DC) electrical stimulation applied at the contralateral wrist. rTMS applied to M1 and DLPFC both significantly elevated the pain threshold at 15 minutes, 30 minutes, and 1 hour after rTMS. However, the analgesic effect of rTMS was stronger when applied to M1. We further compared the rTMS effects with respect to M1 and DLPFC, where electrical stimulation was given through a small concentric electrode that had been shown to stimulate specifically the small A-delta nerve fibers. The analgesic effect of rTMS was measured using a participant-assessed visual analog scale (VAS) ranging from 0 to 10 for no to the most intolerable pain respectively. rTMS at both stimulation sites (M1 and DLPFC) reduced VAS by 20-30% at 15-30 minutes after rTMS, but the effect was not significant compared to sham TMS. Our findings show that high-frequency rTMS is effective to reduce pain sensation when applied to M1 or DLPFC. From the preliminary experiment using small concentric electrodes, we found that rTMS might be also effective to relieve pain mediated by small nerve fibers. Future studies combining rTMS and functional imaging are warranted to identify regions underlying the analgesic effect of rTMS.
Alsamkari, Afraa Awad. "Gene expression in neurological disease: autism and Parkinson's disease." Thesis, 2016. https://hdl.handle.net/2144/19182.
Full textStädtgen, Mario [Verfasser]. "Effects of transcranial magnetic stimulation over the dorsolateral prefrontal cortex on cognitive control and on the autonomic nervous system / vorgelegt von Mario Städtgen." 2008. http://d-nb.info/98983249X/34.
Full textNa, Sabrina. "Practice Effects on a Working Memory Task in Adult Survivors of Pediatric Brain Tumors: An fMRI Investigation." 2015. http://scholarworks.gsu.edu/psych_theses/130.
Full textGrundeis, Felicitas. "The Influence of non-invasive Prefrontal/Frontal Brain Stimulation on Food Reappraisal Abilities and Calorie Consumption in Obese Females." 2019. https://ul.qucosa.de/id/qucosa%3A36271.
Full textLehr, Albert. "Modulation of neuronal excitability in the cognitive control network by electrical stimulation." Thesis, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-139F-3.
Full textKumar, Saurabh. "EEG study on the differences between lean and obese individuals during regulation of food desire." Doctoral thesis, 2017. https://ul.qucosa.de/id/qucosa%3A16798.
Full textLowe, Cassandra. "The effects of continuous theta burst stimulation (cTBS) to the left dorsolateral prefrontal cortex on executive control resources, subjective food cravings, and the consumption of appetitive snack foods." Thesis, 2014. http://hdl.handle.net/10012/8202.
Full textPinho, Ana Luísa Grilo. "Inside of the Creative Mind: Unravelling the Neurocognitive Mechanisms of Musical Creativity." Doctoral thesis, 2015. http://hdl.handle.net/10316/27005.
Full textCreativity emerges from the individual or collective intellect in order to unfold the conundrum of life and give rise to meaningful deliberations for the attainment of a flourishing life. More specifically, creativity is commonly defined, within the framework of psychology, as a creative act or product that shall fulfill two main criteria: (i) it shall be novel (i.e. original and unexpected) and (ii) qualified judges shall agree upon its valuable contribution to the field. The cognitive science approach to creativity investigates the intellectual processes and representations concerned with the creative thinking. The methodologies of cognitive science, derived from the technological advancements of the past sixty years, have begun to adopt a more definitive and systemic perspective. Neuroscience has emerged, under this context, as the scientific study dedicated to explore the biological substrates of the nervous system, by utilizing a multitude of techniques such as neuroimaging. Cognitive neuroscience, in particular, studies the neural correlates of mental processes and it constitutes the central approach here adopted to study musical creativity. The primary goal of this thesis was thus to investigate the neurocognitive mechanisms underlying musical creativity. Functional magnetic resonance imaging was used to measure brain activity in thirty nine professional pianists and musical improvisation was employed as the ecologically valid behavioral model that could most accurately represent creative musical performance. Study I sought to investigate the specific neurocognitive effects derived from expertise in musical improvisation. A natural question that arises is whether extensive improvisational musical training may induce neuroplasticity in the brain. Many of the observed correlates of general musical training reflect not only acquisition of highly specific sensorimotor skills but also cognitive abilities required for various aspects of musical expertise. However, no study has previously focused on the effects of training musical improvisation. The results revealed a significant negative association between improvisational training and activity in a number of cortical regions in the right hemisphere. Also, improvisational training was specifically associated with functional connectivity during musical improvisation, using the premotor and prefrontal regions (previously reported to be involved during extemporization) as seed regions and controlling for age and conventional piano practice. More experienced improvisers showed higher functional connectivity during improvisation between prefrontal, premotor, and motor regions of the frontal lobe. Furthermore, the results were shown not be confounded by more experienced improvisers producing more complex improvisations. Study II explored the contribution of the dorsolateral prefrontal cortex (DLPFC) in creative cognition. Different neuroimaging studies have shown so far seemingly paradoxical results regarding the implications of the DLPFC in creative functioning. On one hand, DLPFC has been argued to exert active control over free generative tasks by inhibiting habitual responses, thus enabling more original output; on the other hand, a deactivation and concomitant decrease in monitoring and focused attention has been suggested to facilitate more spontaneous associations and novel insights. Here, the study highlights that creative cognition can be implemented in different ways given different circumstances. Two categories of behavioral conditions were specified in the experimental design to convey constraints either on the musical structure (set of pitches) or on the emotional expression (happiness or fear) of the improvisations. The results confirmed higher activity in the right DLPFC, as well as in the parietal lobe and right dorsal premotor cortex, when contrasting structural conditions with emotional conditions. These results suggest higher attentional effort and cognitive control when the participants had to conform to the structural constraints. Conversely, deactivations were identified for the emotional constraints in the same regions, plus other regions explicitly contributing to emotion processing. In addition, DLPFC was found functionally connected with the frontoparietal network as well as the cerebellum during structural conditions and to various regions comprising the default network during emotional conditions.
A criatividade emerge do universo intelectual, tanto individual como colectivo, com o objectivo de superar as limitações da existência e de promover decisões que conduzam a uma vida mais plena. No âmbito da psicologia, a criatividade é por norma definida como um acto ou produto criativo que deve cumprir com dois requisitos principais: (i) constituir algo novo (ou seja, ser original e inesperado) e (ii) reunir o consenso dos especialistas acerca da sua contribuição única na área. De acordo com a abordagem seguida em ciências da cognição, a criatividade é estudada a partir dos processos e representações intelectuais envolvidos no pensamento criativo. As respectivas metodologias, decorrentes dos avanços tecnológicos nos últimos sessenta anos, adoptaram uma perspectiva mais definitiva e sistémica. A neurociência surgiu, dentro deste contexto, como o estudo científico que se dedica a investigar os substratos neuronais, recorrendo para isso a uma diversidade de técnicas, entre as quais a neuro-imagem. Em particular, a neurociência da cognição estuda os substratos neuronais associados aos processos mentais, sendo esta a abordagem central adoptada no presente trabalho com vista ao estudo da criatividade musical. O principal objectivo desta tese foi, portanto, investigar os mecanismos neuro-cognitivos subjacentes à criatividade musical. A actividade cerebral de trinta e nove pianistas profissionais foi registada com recurso à ressonância magnética funcional, enquanto estes improvisavam pequenas peças musicais. O estudo I teve o objectivo de investigar os efeitos neuro-cognitivos especificamente decorrentes da experiência em improvisação musical. A questão, aqui colocada, remete-se à identificação dos processos de neuroplasticidade que derivam da prática extensiva em improvisação musical. Muitos dos mecanismos observados e associados ao treino musical reflectem não só a aquisição de habilidades motoras e sensoriais de elevada especificidade, mas também o desenvolvimento de capacidades cognitivas essenciais em diversos aspectos relativos à experiência musical. No entanto, nenhum estudo, até ao momento, se focou nos efeitos relativos à prática improvisacional em música. Os resultados revelaram uma correlação negativa e significativa entre a prática improvisacional e a actividade cerebral, num conjunto de regiões corticais do hemisfério direito. Os resultados evidenciaram, também, que a prática improvisacional está associada a uma maior conectividade funcional entre diversas áreas do córtex pré-frontal, prémotor e motor do lobo frontal, durante a improvisação musical. A idade dos participantes e a prática musical convencional foram introduzidas no modelo de regressão linear como variáveis de controlo. Além disso, os resultados não apresentaram qualquer relação com a complexidade das peças produzidas por pianistas com maior experiência musical. O estudo II examinou a contribuição do córtex pré-frontal dorsolateral (CPFDL) no processo cognitivo criativo. Até agora, diversos estudos em neuro-imagem têm revelado resultados aparentemente paradoxais no que respeita às implicações do CPFDL na actividade funcional responsável pelo pensamento criativo. Por um lado, foi comprovado que o CPFDL exerce um controlo activo sobre tarefas de produção livre, inibindo respostas habituais e promovendo consequentemente resoluções mais originais; por outro lado, a desactivação e concomitante diminuição do CPFDL, durante actividades cognitivas relacionadas com monitorização e concentração, sugere que esta região agiliza processos mentais de associação espontânea e de concretização de novas ideias. O presente estudo destaca que o mecanismo cognitivo associado à criatividade pode ser implementado de diversas formas, dependendo das circunstâncias externas. Duas categorias de restrições foram especificadas no paradigma experimental, de modo a condicionar o comportamento dos participantes. Essas restrições referiam-se à estrutura musical (conjunto de notas) ou à expressão emocional (alegria ou medo) das respectivas improvisações. Os resultados confirmaram uma maior actividade do CPFDL direito, do lobo parietal e do córtex pré-motor dorsal direito, durante a improvisação condicionada pela estrutura da música, quando comparada com a improvisação dependente da expressão emocional transmitida pela música. Os resultados sugeriram, portanto, um esforço maior na atenção prestada e um elevado controlo cognitivo, durante as improvisações condicionadas pela estrutura musical imposta. Em oposição, foram identificadas desactivações nas mesmas regiões, assim como em regiões tipicamente associadas ao processamento de emoções, durante as improvisações cujo desempenho remete para a expressão emocional da música. Além disso, os resultados comprovam que o CPFDL está funcionalmente conectado à rede de comunicação fronto-parietal e ao cerebelo, durante as improvisações condicionadas pela estrutura musical. Por sua vez, os resultados demonstram que o CPFDL está conectado a regiões associadas à rede neuronal em modo padrão, durante as improvisações musicais condicionadas pela expressão emocional.
FCT - SFRH/BD/33895/2009
Costa, Dalila Matos. "Efeitos a curto prazo da combinação da terapia cognitivo comportamental com estimulação transcraniana por corrente contínua na depressão major: um estudo piloto." Master's thesis, 2021. http://hdl.handle.net/1822/75408.
Full textA Perturbação Depressiva Maior (PDM) é das doenças mentais com maior prevalência a nível mundial. A Terapia Cognitivo Comportamental (TCC) é uma abordagem muito utilizada no tratamento da Depressão, tendo um ótimo suporte empírico sobre a sua eficácia. A Estimulação Transcraniana por Corrente Contínua (ETCC) é uma técnica neuromodulatória não invasiva, segura e fácil de usar. Neste estudo clínico piloto, controlado e duplo cego, dez indivíduos com PDM foram randomizados para receber uma de duas condições (TCC combinada com ETCC ativa, n=6; TCC combinada com ETCC sham, n=4) ao longo de 6 semanas de intervenção, havendo monitorização de sintomas num período de 3 meses. Ambos os grupos diminuem a sintomatologia depressiva após o término da intervenção. Contudo é no grupo ativo que se observam melhorias e diferenças estatisticamente significativas no humor e em outras medidas clínicas sintomatológicas nos vários momentos de seguimento. Não obstante aos resultados promissores, é necessário o aumento da amostra.
Major Depressive Disorder (MDD) is one of the most prevalent mental illness worldwide. Cognitive Behavioral Therapy (CBT) is one of the most widely used approaches in the treatment of depression, with excellent empirical support for its effectiveness. Transcranial Direct Current Stimulation (TDC’s) it’s a technique neuromodulatory and non-invasive, safe and easy to use. In this pilot, controlled, double-blind clinical study, ten subjects with MDD were randomized to receive one of two conditions (CBT combined with active TDC’s, n=6; CBT combined with TDC’s sham, n=4) over 6 weeks of intervention, with symptom monitoring over a period of 3 months. Both groups decrease the depressive symptoms after the end of the intervention. However, it is in the active group that there are statistically significant improvements and differences in mood and in other symptomatic clinical measures at different times of follow-up. Despite the promising results, it is necessary to increase the sample.
VILLA, SANCHEZ BERNARDO. "The placebo effect in the motor domain: a neural and behavioral approach." Doctoral thesis, 2019. http://hdl.handle.net/11562/995396.
Full textDeldar, Zoha. "Rehaussement de la mémoire de travail et de l'inhibition de la douleur par la neuromodulation du cortex préfrontal dorsolatéral gauche chez des personnes jeunes et âgées = Improving working memory and pain inhibition using neuromodulation of left dorsolateral prefrontal cortex in young and older persons." Thèse, 2019. http://depot-e.uqtr.ca/id/eprint/9220/1/032342541.pdf.
Full textChand, Ganesh. "Oscillatory Network Dynamics in Perceptual Decision-Making." 2015. http://scholarworks.gsu.edu/phy_astr_diss/79.
Full textLafontaine, Marc Philippe. "Modulation de l'apprentissage visuel par stimulation électrique transcrânienne à courant direct du cortex préfrontal." Thèse, 2012. http://hdl.handle.net/1866/8997.
Full textRepeated visual processing of an unfamiliar face suppresses neural activity in face-specific areas of the occipito-temporal cortex. This "repetition suppression" (RS) is a primitive mechanism involved in learning of unfamiliar faces, which can be detected through amplitude reduction of the N170 event-related potential (ERP). The dorsolateral prefrontal cortex (DLPFC) exerts top-down influence on early visual processing. However, its contribution to N170 RS and learning of unfamiliar faces remains unclear. Transcranial direct current stimulation (tDCS) transiently increases or decreases cortical excitability, as a function of polarity. We hypothesized that DLPFC excitability modulation by tDCS would cause polarity-dependent modulations of N170 RS during encoding of unfamiliar faces. tDCS-induced N170 RS enhancement would improve long-term recognition reaction time (RT) and/or accuracy rates, whereas N170 RS impairment would compromise recognition ability. Participants underwent three tDCS conditions in random order at ~72 hour intervals: right anodal/left cathodal, right cathodal/left anodal and sham. Immediately following tDCS conditions, an EEG was recorded during encoding of unfamiliar faces for assessment of P100 and N170 visual ERPs. P300 was analyzed to detect prefrontal function modulation. Recognition tasks were administered ~72 hours following encoding. Results indicate the right anodal/left cathodal condition facilitated N170 RS and induced larger P300 amplitudes, leading to faster recognition RT. Conversely, the right cathodal/left anodal condition caused increases in N170 amplitudes and RT, but did not affect P300. These data are the first to demonstrate that DLPFC excitability modulation can influence early visual encoding of unfamiliar faces, highlighting the importance of DLPFC in basic learning mechanisms.
Calvo, Alberto Lema. "Transcranial Random Noise Stimulation (tRNS) on Attention Network Test (ANT): an exploratory study." Master's thesis, 2017. http://hdl.handle.net/1822/48135.
Full textSpeed-accuracy tradeoff (SAT) refers to the adjustment between response speed and its accuracy, a process mediated through cortical and subcortical circuits. However, it remains unclear whether SAT can be modulated by the effects of tRNS and/or tDCS. In order to explore this effect, we used the attention network test (ANT). This tasks allowed us to test three independent networks related to both subcortical activity (alerting and orienting) and cortical level (executive). We hypothesized that performance would increase for alerting and orienting networks with tRNS whereas tDCS would increase performance in executive network. Moreover, to make the SAT effect more prominent, instructions that emphasized speed and accuracy were also introduced. Eighteen healthy students undertook three experimental sessions of tRNS, anodal tDCS and sham over the left dlPFC while performing the ANT. Results showed that no significant effect was found for stimulation. Instructions, however, showed a significant difference between speed condition and standard condition. Thus, SAT was successfully manipulated by instruction condition but not by stimulation.
O Speed-accuracy tradeoff (SAT) é definido como o ajustamento entre a velocidade e a exatidão de uma determinada resposta. Este processo é mediado por vias corticais e subcorticais suceptíveis de serem alteradas através de métodos de estimulação elétrica transcraniana. No presente estudo, dois tipos de estimulação, ETRN e ETCC, foram combinados com uma tarefa atencional (ANT) com o intuito de avaliar os seus efeitos nas vias corticais e subcorticais associadas ao SAT. Era esperado que a ETRN aumentasse o desempenho em vias atencionais subcorticais (de alerta e de orientação) enquanto que a ETCC melhorasse o desempenho na via atencional cortical (executiva). De igual modo, as instruções da tarefa também foram alteradas para manipular o SAT, favorecendo assim a velocidade ou a exatidão da resposta. Dezoito participantes saudáveis receberam de forma aleatorizada três sessões de estimulação (ETRN, ETCC, sham) unilateral sobre o CPFDL esquerdo. Os resultados mostram que a estimulação ETRN e ETCC não obteveram efeitos nas vias atentionais. As instruções, no entanto, revelam que quando o ênfase é colocado na velocidade da resposta, a via atencional executiva apresenta menor eficiência. Desta forma, O SAT apenas foi manipulado com sucesso através das intruções e não da estimulação.
Silva, Afonso Jorge Vaz da. "Estimulação transcraniana por corrente contínua combinada com terapia cognitivo comportamental no tratamento da depressão major." Master's thesis, 2020. http://hdl.handle.net/1822/69723.
Full textA Perturbação Depressiva Major (PDM) é uma doença mental com grande prevalência a nível mundial. Como tratamento padronizado não-farmacológico, a Terapia Cognitivo Comportamental (TCC) é uma técnica terapêutica com um bom suporte-empírico estabelecido para a depressão. Por sua vez, a Estimulação Transcraniana por Corrente Contínua (ETCC) é uma técnica neuromodulatória segura, não-invasiva, económica, fácil de administrar e indolor. Apesar da já evidenciada eficácia, não são claros os efeitos da combinação das duas técnicas na redução dos sintomas da PDM. Neste estudo clínico piloto, controlado e duplo cego, seis sujeitos diagnosticados com PDM foram randomizados para receberem uma de duas condições possíveis. A primeira, TCC combinada com ETCC ativa bilateral sobre o córtex pré-frontal dorsolateral ou a segunda, TCC combinada com ETCC sham, ao longo das seis semanas de intervenção. Os indivíduos foram posteriormente seguidos durante um período de três meses. Ambos os grupos melhoraram significativamente na sintomatologia depressiva após término da intervenção, contudo não se encontraram diferenças estatisticamente significativas entre os grupos. Estes efeitos mantiveram-se ao longo do seguimento. Apesar dos resultados promissores, é fundamental o aumento do tamanho da amostra.
Major Depressive Disorder (MDD) is a mental illness with a high worldwide prevalence. As a standardized non-pharmacological treatment, the Cognitive Behavioral Therapy (CBT) is a therapeutic technique well-established, and empirically supported for depression, including for those that have not responded to antidepressants. Transcranial Direct Current Stimulation (tDCS) is a safe, non-invasive, not expensive, easy to administrate, and well tolerated neuromodulatory technique. Despite the already proven effectiveness, it is not yet clear what are the effects of using the combination of these two interventions on MDD symptoms. In this pilot clinical trial, double-blind study, a total of six subjects with MDD were randomized to receive CBT combined with bilateral active tDCS over the DLPFC or CBT combined with sham tDCS, during six weeks of intervention. Subsequently, the participants were followed by three months. The participant’s humor significantly ameliorated in both groups after the treatment, however there was no statistically significant differences between groups. These effects remained during follow up assessments. Future studies should increase the sample size.
Este projeto está financiado pela Fundação para a Ciência e a Tecnologia (FCT) - PTDC/PSI-ESP/29701/2017
Kremer, Kristina. "Vergleichende MR-volumetrische Untersuchung des dorsolateralen präfrontalen Kortex bei Schizophrenie, Bipolarer Störung, Zwangserkrankung und gesunden Kontrollpersonen." Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-0006-B1BF-3.
Full textPohlers, Henriette. "Einfluss der transkraniellen Gleichstromstimulation auf die stimmungsabhängige Informationsverarbeitung bei gesunden Probanden." Doctoral thesis, 2012. http://hdl.handle.net/11858/00-1735-0000-0006-B2B3-4.
Full textDumont, Laurence. "Évaluation systématique des effets de la tDCS sur le DLPFC et applications en technologies de l'information." Thèse, 2017. http://hdl.handle.net/1866/20616.
Full textAmbrus, Géza Gergely. "Low Intensity Transcranial Electrical Stimulation: Effects on Categorization and Methodological Aspects." Doctoral thesis, 2012. http://hdl.handle.net/11858/00-1735-0000-000D-EF6F-7.
Full textSiegle, Micha Benjamin. "Einfluss von transkraniellen Wechselstromstimulationen im Thetabereich auf die Bearbeitung der Stroop-Aufgabe." Doctoral thesis, 2021. http://hdl.handle.net/21.11130/00-1735-0000-0005-15A1-D.
Full text