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1.
Sleep Breath ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38760629

RESUMO

PURPOSE: Little is known about cognitive complaints (self-reported problems in cognitive functioning) in patients with Obstructive Sleep Apnea (OSA). We compared the prevalence and severity of cognitive complaints in patients with untreated OSA to patients with neurological and respiratory diseases. We also studied risk factors for cognitive complaints across these diseases, including OSA. METHODS: We used a convenience sample to compare untreated OSA patients (N = 86) to patients with stroke (N = 166), primary brain tumor (N = 197) and chronic obstructive pulmonary disease (COPD, N = 204) on cognitive complaints (Cognitive Failure Questionnaire, CFQ), anxiety and depression (Hospital Anxiety and Depression Scale, HADS) and cognitive impairments using neuropsychological tests. We combined all patient groups (OSA, stroke, brain tumor and COPD) and studied potential risk factors (demographic variables, anxiety, depression and cognitive impairments) for cognitive complaints across all patient groups using regression analysis. RESULTS: The prevalence of cognitive complaints was higher in OSA patients and complaints of forgetfulness and distractibility were more severe compared to stroke and primary brain tumor patients, but similar to or lower than COPD patients. Regression analysis for the combined sample of all patient groups showed that cognitive complaints were most strongly associated with symptoms of anxiety and depression. CONCLUSION: A high rate of OSA reported clinically significant cognitive complaints, comparable to other respiratory and neurological patients. Symptoms of anxiety and depression are important risk factors for cognitive complaints in patients with various neurological and respiratory diseases. Future studies should examine the relation between anxiety, depression and cognitive complaints in patients with OSA.

2.
BMC Med Inform Decis Mak ; 24(1): 177, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907265

RESUMO

BACKGROUND: Enhancing Local Control (LC) of brain metastases is pivotal for improving overall survival, which makes the prediction of local treatment failure a crucial aspect of treatment planning. Understanding the factors that influence LC of brain metastases is imperative for optimizing treatment strategies and subsequently extending overall survival. Machine learning algorithms may help to identify factors that predict outcomes. METHODS: This paper systematically reviews these factors associated with LC to select candidate predictor features for a practical application of predictive modeling. A systematic literature search was conducted to identify studies in which the LC of brain metastases is assessed for adult patients. EMBASE, PubMed, Web-of-Science, and the Cochrane Database were searched up to December 24, 2020. All studies investigating the LC of brain metastases as one of the endpoints were included, regardless of primary tumor type or treatment type. We first grouped studies based on primary tumor types resulting in lung, breast, and melanoma groups. Studies that did not focus on a specific primary cancer type were grouped based on treatment types resulting in surgery, SRT, and whole-brain radiotherapy groups. For each group, significant factors associated with LC were identified and discussed. As a second project, we assessed the practical importance of selected features in predicting LC after Stereotactic Radiotherapy (SRT) with a Random Forest machine learning model. Accuracy and Area Under the Curve (AUC) of the Random Forest model, trained with the list of factors that were found to be associated with LC for the SRT treatment group, were reported. RESULTS: The systematic literature search identified 6270 unique records. After screening titles and abstracts, 410 full texts were considered, and ultimately 159 studies were included for review. Most of the studies focused on the LC of the brain metastases for a specific primary tumor type or after a specific treatment type. Higher SRT radiation dose was found to be associated with better LC in lung cancer, breast cancer, and melanoma groups. Also, a higher dose was associated with better LC in the SRT group, while higher tumor volume was associated with worse LC in this group. The Random Forest model predicted the LC of brain metastases with an accuracy of 80% and an AUC of 0.84. CONCLUSION: This paper thoroughly examines factors associated with LC in brain metastases and highlights the translational value of our findings for selecting variables to predict LC in a sample of patients who underwent SRT. The prediction model holds great promise for clinicians, offering a valuable tool to predict personalized treatment outcomes and foresee the impact of changes in treatment characteristics such as radiation dose.


Assuntos
Neoplasias Encefálicas , Aprendizado de Máquina , Humanos , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia
3.
J Neurosci Res ; 101(12): 1826-1839, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37694505

RESUMO

In healthy subjects, activity in the default mode network (DMN) and the frontoparietal network (FPN) has consistently been associated with working memory (WM). In particular, the dorsolateral prefrontal cortex (DLPFC) is important for WM. The functional-anatomical basis of WM impairment in glioma patients is, however, still poorly understood. We investigated whether WM performance of glioma patients is reflected in resting-state functional connectivity (FC) between the DMN and FPN, additionally focusing on the DLPFC. Resting-state functional MRI data were acquired from 45 glioma patients prior to surgery. WM performance was derived from a pre-operative N-back task. Scans were parcellated into ROIs using both the Gordon and Yeo atlas. FC was calculated as the average Pearson correlation between functional time series. The FC between right DLPFC and DMN was inversely related to WM performance for both the Gordon and Yeo atlas (p = .010). No association was found for FC between left DLPFC and DMN, nor between the whole FPN and DMN. The results are robust and not dependent on atlas choice or tumor location, as they hold for both the Gordon and Yeo atlases, and independently of location variables. Our findings show that WM performance of glioma patients can be quantified in terms of interactions between regions and large-scale networks that can be measured with resting-state fMRI. These group-based results are a necessary step toward development of biomarkers for clinical management of glioma patients, and provide additional evidence that global disruption of the DMN relates to cognitive impairment in glioma patients.

4.
J Neurooncol ; 160(3): 619-629, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36346497

RESUMO

OBJECTIVE: As preservation of cognitive functioning increasingly becomes important in the light of ameliorated survival after intracranial tumor treatments, identification of eloquent brain areas would enable optimization of these treatments. METHODS: This cohort study enrolled adult intracranial tumor patients who received neuropsychological assessments pre-irradiation, estimating processing speed, verbal fluency and memory. Anatomical magnetic resonance imaging scans were used for multivariate voxel-wise lesion-symptom predictions of the test scores (corrected for age, gender, educational level, histological subtype, surgery, and tumor volume). Potential effects of histological and molecular subtype and corresponding WHO grades on the risk of cognitive impairment were investigated using Chi square tests. P-values were adjusted for multiple comparisons (p < .001 and p < .05 for voxel- and cluster-level, resp.). RESULTS: A cohort of 179 intracranial tumor patients was included [aged 19-85 years, median age (SD) = 58.46 (14.62), 50% females]. In this cohort, test-specific impairment was detected in 20-30% of patients. Higher WHO grade was associated with lower processing speed, cognitive flexibility and delayed memory in gliomas, while no acute surgery-effects were found. No grading, nor surgery effects were found in meningiomas. The voxel-wise analyses showed that tumor locations in left temporal areas and right temporo-parietal areas were related to verbal memory and processing speed, respectively. INTERPRETATION: Patients with intracranial tumors affecting the left temporal areas and right temporo-parietal areas might specifically be vulnerable for lower verbal memory and processing speed. These specific patients at-risk might benefit from early-stage interventions. Furthermore, based on future validation studies, imaging-informed surgical and radiotherapy planning could further be improved.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Meníngeas , Feminino , Humanos , Adulto , Masculino , Estudos de Coortes , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Glioma/patologia , Testes Neuropsicológicos , Imageamento por Ressonância Magnética/métodos
5.
Acta Neurochir (Wien) ; 164(1): 177-191, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34674026

RESUMO

BACKGROUND: Over the past decade, the functional importance of white matter pathways has been increasingly acknowledged in neurosurgical planning. A method to directly study anatomo-functional correlations is direct electrical stimulation (DES). DES has been widely accepted by neurosurgeons as a reliable tool to minimize the occurrence of permanent postoperative motor, vision, and language deficits. In recent years, DES has also been used for stimulation mapping of other cognitive functions, such as executive functions and visuospatial awareness. METHODS: The aim of this review is to summarize the evidence so far from DES studies on subcortical pathways that are involved in visuospatial awareness and in the following three executive functions: (1) inhibitory control, (2) working memory, and (3) cognitive flexibility. RESULTS: Eleven articles reported on intraoperative electrical stimulation of white matter pathways to map the cognitive functions and explicitly clarified which subcortical tract was stimulated. The results indicate that the right SLF-II is involved in visuospatial awareness, the left SLF-III and possibly the right SLF-I are involved in working memory, and the cingulum is involved in cognitive flexibility. CONCLUSIONS: We were unable to draw any more specific conclusions, nor unequivocally establish the critical involvement of pathways in executive functions or visuospatial awareness due to the heterogeneity of the study types and methods, and the limited number of studies that assessed these relationships. Possible approaches for future research to obtain converging and more definite evidence for the involvement of pathways in specific cognitive functions are discussed.


Assuntos
Neoplasias Encefálicas , Glioma , Mapeamento Encefálico , Estimulação Elétrica , Humanos , Idioma
6.
J Cogn Neurosci ; 33(12): 2512-2522, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34407188

RESUMO

The question whether and how we are able to monitor our own cognitive states (metacognition) has been a matter of debate for decades. Do we have direct access to our cognitive processes, or can we only infer them indirectly based on their consequences? In the current study, we wanted to investigate the brain circuits that underlie the metacognitive experience of fluency in action selection. To manipulate action-selection fluency, we used a subliminal response priming paradigm. On each trial, both male and female human participants additionally engaged in the metacognitive process of rating how hard they felt it was to respond to the target stimulus. Despite having no conscious awareness of the prime, results showed that participants rated incompatible trials (during which subliminal primes interfered with the required response) to be more difficult than compatible trials (where primes facilitated the required response), reflecting metacognitive awareness of difficulty. This increased sense of subjective difficulty was mirrored by increased activity in the rostral cingulate zone and the anterior insula, two regions that are functionally closely connected. Importantly, this reflected activations that were unique to subjective difficulty ratings and were not explained by RTs or prime-response compatibility. We interpret these findings in light of a possible grounding of the metacognitive judgment of fluency in action selection in interoceptive signals resulting from increased effort.


Assuntos
Metacognição , Conscientização , Feminino , Humanos , Julgamento , Masculino
7.
J Int Neuropsychol Soc ; 26(2): 187-196, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31699166

RESUMO

OBJECTIVE: This study aimed to examine: (1) patient-proxy agreement on executive functioning (EF) of patients with primary brain tumors, (2) the relationships between patient- and proxy-report with performance-based measures of EF, and (3) the potential influence of performance-based measures on the level of agreement. METHODS: Meningioma and low-grade glioma patients and their informal caregivers completed the Behavior Rating Inventory of Executive Function (BRIEF-A) 3 months after surgery. The two index scores of the BRIEF-A, Behavioral Regulation and Metacognition, were evaluated. Mean scores of patients and proxies were compared with normative values and with each other. Patient-proxy agreement was evaluated with Lin's concordance correlation coefficients (CCCs) and Bland-Altman plots. Pearson correlation coefficients between reported EF and performance-based measures of EF were calculated. Multiple regression analysis was used to evaluate the potential influence of test performance on differences in dyadic reports. RESULTS: A total of 47 dyads were included. Patients reported significantly more problems on the Metacognition Index compared to norms, and also in comparison with their proxies. Effect sizes indicated small differences. Moderate to substantial agreement was observed between patients and proxies, with CCCs of 0.57 and 0.61 for Metacognition and Behavioral Regulation, respectively. Correlations between reported EF and test performance ranged between -0.37 and 0.10. Dyadic agreement was not significantly influenced by test performance. CONCLUSIONS: Patient-proxy agreement was found to be moderate. No clear associations were found between reported EF and test performance. Future studies should further explore the existing and new methods to assess everyday EF in brain tumor patients.


Assuntos
Neoplasias Encefálicas/complicações , Cuidadores , Disfunção Cognitiva/diagnóstico , Função Executiva , Glioma/complicações , Meningioma/complicações , Metacognição , Desempenho Psicomotor , Autorrelato , Escala de Avaliação Comportamental , Neoplasias Encefálicas/cirurgia , Disfunção Cognitiva/etiologia , Função Executiva/fisiologia , Feminino , Seguimentos , Glioma/cirurgia , Humanos , Masculino , Meningioma/cirurgia , Metacognição/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Procedimentos Neurocirúrgicos , Medidas de Resultados Relatados pelo Paciente , Desempenho Psicomotor/fisiologia
8.
Eur J Neurosci ; 50(12): 3921-3933, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31370107

RESUMO

Previous studies have shown that cognitive functioning in patients with brain tumour is associated with the functional network characteristics of specific resting-state networks or with whole-brain network characteristics. These studies, however, did not acknowledge the functional contribution of areas in the contralesional, non-tumoural hemisphere, even though these healthy remote areas likely play a critical role in compensating for the loss of function in damaged tissue. In the current study, we examined whether there is an association between cognitive performance and functional network features of the contralesional hemisphere of patients with glioma. We found that local efficiency of the contralesional hemisphere was associated with performance on the reaction time domain, whereas contralesional assortativity was associated with complex attention and cognitive flexibility scores. Our results suggest that a less segregated organization of the contralesional hemisphere is associated with better reaction time scores, whereas a better spread of information over the contralesional hemisphere through mutually interconnected contralesional hubs is associated with better cognitive flexibility and better complex attention scores. These findings urge researchers to recognize the functional contribution of remote, undamaged regions and to focus more on the graph metrics of the contralesional hemisphere in the search for predictors of cognitive functioning in patients with brain tumour.


Assuntos
Atenção/fisiologia , Neoplasias Encefálicas/fisiopatologia , Encéfalo/fisiopatologia , Cognição/fisiologia , Glioma/fisiopatologia , Adulto , Mapeamento Encefálico/métodos , Feminino , Lateralidade Funcional/fisiologia , Glioma/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/fisiopatologia , Vias Neurais/fisiopatologia
9.
Cereb Cortex ; 27(3): 1891-1905, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-26908634

RESUMO

Task preparation has traditionally been thought to rely upon persistent representations of instructions that permit their execution after delays. Accumulating evidence suggests, however, that accurate retention of task knowledge can be insufficient for successful performance. Here, we hypothesized that instructed facts would be organized into a task set; a temporary coding scheme that proactively tunes sensorimotor pathways according to instructions to enable highly efficient "reflex-like" performance. We devised a paradigm requiring either implementation or memorization of novel stimulus-response mapping instructions, and used multivoxel pattern analysis of neuroimaging data to compare neural coding of instructions during the pretarget phase. Although participants could retain instructions under both demands, we observed striking differences in their representation. To-be-memorized instructions could only be decoded from mid-occipital and posterior parietal cortices, consistent with previous work on visual short-term memory storage. In contrast, to-be-implemented instructions could also be decoded from frontoparietal "multiple-demand" regions, and dedicated visual areas, implicated in processing instructed stimuli. Neural specificity in the latter moreover correlated with performance speed only when instructions were prepared, likely reflecting the preconfiguration of instructed decision circuits. Together, these data illuminate how the brain proactively optimizes performance, and help dissociate neural mechanisms supporting task control and short-term memory storage.


Assuntos
Antecipação Psicológica/fisiologia , Função Executiva/fisiologia , Lobo Frontal/fisiologia , Memória de Curto Prazo/fisiologia , Lobo Parietal/fisiologia , Córtex Visual/fisiologia , Mapeamento Encefálico , Feminino , Objetivos , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tempo de Reação , Reconhecimento Psicológico/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
10.
Neuroimage ; 162: 106-116, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28870853

RESUMO

Although research has now converged towards a consensus that both languages of a bilingual are represented in at least partly shared systems for language comprehension, it remains unclear whether both languages are represented in the same neural populations for production. We investigated the neural overlap between L1 and L2 semantic representations of translation equivalents using a production task in which the participants had to name pictures in L1 and L2. Using a decoding approach, we tested whether brain activity during the production of individual nouns in one language allowed predicting the production of the same concepts in the other language. Because both languages only share the underlying semantic representation (sensory and lexical overlap was maximally avoided), this would offer very strong evidence for neural overlap in semantic representations of bilinguals. Based on the brain activation for the individual concepts in one language in the bilateral occipito-temporal cortex and the inferior and the middle temporal gyrus, we could accurately predict the equivalent individual concepts in the other language. This indicates that these regions share semantic representations across L1 and L2 word production.


Assuntos
Encéfalo/fisiologia , Multilinguismo , Semântica , Fala/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
11.
Neuroimage ; 126: 96-105, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26608243

RESUMO

To minimize the number of errors in speech, and thereby facilitate communication, speech is monitored before articulation. It is, however, unclear at which level during speech production monitoring takes place, and what mechanisms are used to detect and correct errors. The present study investigated whether internal verbal monitoring takes place through the speech perception system, as proposed by perception-based theories of speech monitoring, or whether mechanisms independent of perception are applied, as proposed by production-based theories of speech monitoring. With the use of fMRI during a tongue twister task we observed that error detection in internal speech during noise-masked overt speech production and error detection in speech perception both recruit the same neural network, which includes pre-supplementary motor area (pre-SMA), dorsal anterior cingulate cortex (dACC), anterior insula (AI), and inferior frontal gyrus (IFG). Although production and perception recruit similar areas, as proposed by perception-based accounts, we did not find activation in superior temporal areas (which are typically associated with speech perception) during internal speech monitoring in speech production as hypothesized by these accounts. On the contrary, results are highly compatible with a domain general approach to speech monitoring, by which internal speech monitoring takes place through detection of conflict between response options, which is subsequently resolved by a domain general executive center (e.g., the ACC).


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Conflito Psicológico , Função Executiva/fisiologia , Percepção da Fala/fisiologia , Fala/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
12.
Eur Eat Disord Rev ; 24(4): 277-85, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26856396

RESUMO

In this study, possible differences in the neural correlates of set-shifting abilities between the restrictive (AN-R) and bingeing/purging (AN-BP) subtypes of anorexia nervosa have been explored. Three groups of participants performed a set-shifting task during functional magnetic resonance imaging: patients with AN-R (N = 16), AN-BP (N = 13) and healthy control participants (N = 15). As in a typical set-shifting experiment, participants had to switch between two easy tasks (i.e. 'Is the presented number odd/even' or 'Is the presented number smaller/larger than 5'). The trials in which the task was repeated (repeat trials) were compared with trials in which the task was switched (switch trials). With regards to the level of task performance, no significant group differences could be established. However, when comparing switch specific brain activity across study groups, a stronger activation was found in the insula and the precuneus in AN-R when compared to AN-BP and HC. These results suggest that the both subtypes of AN might have different neurobiological correlates, and thus, might benefit from different treatment approaches. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.


Assuntos
Anorexia Nervosa/diagnóstico por imagem , Transtorno da Compulsão Alimentar/diagnóstico por imagem , Imageamento por Ressonância Magnética , Testes Neuropsicológicos/estatística & dados numéricos , Enquadramento Psicológico , Adulto , Anorexia Nervosa/classificação , Estudos de Casos e Controles , Cognição , Função Executiva , Feminino , Humanos , Escalas de Graduação Psiquiátrica
13.
J Cogn Neurosci ; 27(9): 1752-65, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25901448

RESUMO

Controlling multiple languages during speech production is believed to rely on functional mechanisms that are (at least partly) shared with domain-general cognitive control in early, highly proficient bilinguals. Recent neuroimaging results have indeed suggested a certain degree of neural overlap between language control and nonverbal cognitive control in bilinguals. However, this evidence is only indirect. Direct evidence for neural overlap between language control and nonverbal cognitive control can only be provided if two prerequisites are met: Language control and nonverbal cognitive control should be compared within the same participants, and the task requirements of both conditions should be closely matched. To provide such direct evidence for the first time, we used fMRI to examine the overlap in brain activation between switch-specific activity in a linguistic switching task and a closely matched nonlinguistic switching task, within participants, in early, highly proficient Spanish-Basque bilinguals. The current findings provide direct evidence that, in these bilinguals, highly similar brain circuits are involved in language control and domain-general cognitive control.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Função Executiva/fisiologia , Multilinguismo , Adolescente , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Testes Neuropsicológicos , Adulto Jovem
14.
Neuroimage ; 99: 332-41, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24875143

RESUMO

Throughout the past decade, the task-switching paradigm has been used extensively as a tool to delineate the neural mechanisms underlying flexible and goal-directed action control. Yet, given a large number of experimental procedures, the task-switching literature has yielded considerable inconsistencies calling for a systematic evaluation of the impact of methodological parameters. In the present study, we examine a fundamental and implicit assumption that has guided previous research on task switching. Does switch-related brain activation (i.e., the contrast between preparatory activity on switch versus repetition trials) reflect abstract cognitive control processes that are independent of specific task demands, and thus equivalent across different types of tasks? To answer this question, we compared the data of two fMRI studies that examined updating of task goals and/or stimulus-response mappings under almost identical protocols, but using entirely different tasks. In line with an abstract control process view, our results show that the vast majority of switch-related brain activity is insensitive to the context in which it occurs. The only region that exhibited a reliable contextual modulation was the anterior cingulate cortex, indicating that its contribution to preparatory adjustments might be linked to specific task demands.


Assuntos
Encéfalo/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Cognição/fisiologia , Sinais (Psicologia) , Discriminação Psicológica/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
15.
Brain Struct Funct ; 229(5): 1209-1223, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38656375

RESUMO

Several studies predicting Functional Connectivity (FC) from Structural Connectivity (SC) at individual level have been published in recent years, each promising increased performance and utility. We investigated three of these studies, analyzing whether the results truly represent a meaningful individual-level mapping from SC to FC. Using data from the Human Connectome Project shared accross the three studies, we constructed a predictor by averaging FC of training data and analyzed its performance in the same way. In each case, we found that group average FC is an equivalent or better predictor of individual FC than the predictive models in terms of raw prediction performance. Furthermore, we showed that additional analyses performed by the authors of the three studies, in which they attempt to show that their predicted FC has value beyond raw prediction performance, could also be reproduced using the group average FC predictor. This makes it unclear whether any of the three methods represent a meaningful individual-level predictive model. We conclude that either the methods are not appropriate for the data, that the sample size is too small, or that the data does not contain sufficient information to learn a mapping from SC to FC. We advise future individual-level studies to explicitly report results in comparison to the performance of the group average, and carefully demonstrate that their predictions contain meaningful individual-level information. Finally, we believe that investigating alternatives for the construction of SC and FC may improve the chances of developing a meaningful individual-level mapping from SC to FC.


Assuntos
Encéfalo , Conectoma , Imageamento por Ressonância Magnética , Humanos , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Masculino , Feminino , Vias Neurais/fisiologia , Adulto , Mapeamento Encefálico/métodos
16.
Brain Imaging Behav ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722525

RESUMO

Patients with meningiomas frequently exhibit impairments in executive functioning. There are few studies specifically examining the role of frontal meningioma localization in executive functioning impairments. This study examines whether frontally located meningiomas are specifically associated with executive functioning impairments in a large sample of meningioma patients before treatment, using an axis-wise and lobe-based approach to meningioma localization. We retrospectively examined cognitive performances in 353 patients with frontal, frontally-involved and non-frontal meningiomas on a battery of tests including tests of executive functioning. We applied an axis-based approach to meningioma location, in addition to qualitative lobe-based localization. We examined the association between meningioma coordinates on an anterior-posterior axis and continuous cognitive performance scores in univariate correlations and linear regression analyses. We also examined the association between meningioma coordinates on an anterior-posterior axis with cognitive impairments in multivariable logistic regression analyses. Meningioma position on the anterior-posterior axis was only univariately associated with mean performance on the Stroop test Interference ratio and Symbol Digit Coding task. There was no (multivariable) association with impairments on tests of executive or non-executive domains. Increased odds of impairment on executive functioning tasks were associated with left-localization (Verbal Fluency) and larger meningioma volumes (Shifting Attention). We did not find a specific relation between a frontal meningioma location and executive functioning impairments, which may be explained by widespread organization of executive functioning throughout the brain, diffuse cognitive effects of the mass of meningiomas, functional reorganization due to neuroplasticity, or functional involvement of less-anteriorly located frontal areas.

17.
J Cogn Neurosci ; 25(5): 777-89, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23469883

RESUMO

Stimulus repetition produces a decrease of the response in many cortical areas and different modalities. This adaptation is highly prominent in macaque inferior temporal (IT) neurons. Here we ask how these repetition-induced changes in IT responses affect the accuracy by which IT neurons encode objects. This question bears on the functional consequences of adaptation, which are still unclear. We recorded the responses of single IT neurons to sequences of familiar shapes, each shown for 300 msec with an ISI of the same duration. The difference in shape between the two successively presented stimuli,that is, adapter and test, varied parametrically. The discriminability of the test stimuli was reduced for repeated compared with nonrepeated stimuli. In some conditions for which adapter and test shapes differed, the cross-adaptation resulted in an enhanced discriminability. These single cell results were confirmed in a second experiment in which we recorded multiunit spiking activity using a laminar microelectrode in macaque IT. Two familiar stimuli were presented successively for 500 msec each and separated with an ISI of the same duration. Trials consisted either of a repetition of the same stimulus or of their alternation. Small neuronal populations showed decreased classification accuracy for repeated compared with nonrepeated test stimuli, but classification was enhanced for the test compared with adapter stimuli when the test stimulus differed from recently seen stimuli. These findings suggest that short-term, stimulus-specific adaptation in IT supports efficient coding of stimuli that differ from recently seen ones while impairing the coding of repeated stimuli.


Assuntos
Adaptação Fisiológica/fisiologia , Discriminação Psicológica/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Lobo Temporal/fisiologia , Potenciais de Ação/fisiologia , Análise de Variância , Animais , Potenciais Evocados Visuais/fisiologia , Macaca mulatta , Neurônios/fisiologia , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Lobo Temporal/citologia , Fatores de Tempo
18.
Neuroimage ; 77: 207-14, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23567890

RESUMO

Cognitive control processes refer to the ability to flexibly adapt one's thoughts and actions in the pursuit of an internal goal. Task preparation is a central aspect of cognitive control and has generally been studied using explicitly cued task-switching paradigms. Over the last decade, numerous fMRI studies have identified a fronto-parietal network to exhibit greater activity during the preparation of task switches than during the preparation of task repetitions, which is assumed to reflect endogenous cognitive control processes. There is, however, a huge variability in preparatory switch-specific brain activity reported in the imaging literature on task-switching. One factor that might explain this heterogeneity is the difference in switch probability across studies. In the current fMRI study, we examined which preparation-related cognitive control areas are susceptible to such contextual differences by manipulating the switch probability within subjects. In the low switch probability (30% switch trials) blocks, we found the frequently observed switch-related preparatory activation in fronto-parietal areas. In the high switch probability (50% switch trials) blocks, however, only part of these areas (more particularly the (pre-) SMA, extending into the dorsal ACC and the superior parietal lobule) showed higher activation in switch compared to repeat trials. The activation levels in the other areas (the lateral prefrontal cortex, inferior parietal lobule and middle temporal gyrus) were very similar for switch and repeat trials. Our results suggest a functional dissociation within the cognitive control network with some brain areas being sensitive to the switch probability context while others are not.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Cognição/fisiologia , Vias Neurais/fisiologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem
19.
Neuroimage ; 72: 207-13, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23384520

RESUMO

Humans have the ability to choose freely between different alternatives. It is common knowledge, however, that our free choices are influenced by the environment and by past experiences. In the present study we investigated if the involvement of the medial frontal cortex, which is known to be important for intentional control, depends on whether free choices are biased by past experiences. By using fMRI, we observed that the rostral cingulate zone (RCZ) is less activated during biased than during unbiased choices. On the basis of this finding we argue that the RCZ plays a specific role in intentional control of action by evaluating which alternative is most appropriate in a given context. In addition, we observed that free choices were biased more during mind wandering episodes than during on-task episodes. This finding suggests that during periods of mind wandering, attention is shifted away from the primary task and external factors can influence the choice process more easily.


Assuntos
Mapeamento Encefálico , Comportamento de Escolha/fisiologia , Lobo Frontal/fisiologia , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
20.
Eur Eat Disord Rev ; 21(4): 308-14, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23674268

RESUMO

OBJECTIVE: Anorexia nervosa (AN) has been associated with weak central coherence (CC) and weak set shifting (SS). The main aim of this study was to examine possible differences between restrictive AN (AN-R) and bingeing/purging AN (AN-BP) on these features. METHODS: A total of 31 patients with AN-R, 20 patients with AN-BP and 26 healthy controls (HC) completed five neuropsychological tests (Block Design, Object Assembly, an adapted task-switching paradigm, Wisconsin Card Sorting Test and Trail Making Test). RESULTS: Using Block Design and Object Assembly, indicative for CC, AN-R patients performed significantly worse than AN-BP patients and HC, without any difference between AN-BP and HC. On SS measures, no group differences were observed. DISCUSSION: The results suggest that cognitive profiles of AN-R and AN-BP patients differ significantly on CC and not on SS. Our current findings support the idea that the two subtypes of AN have a distinctive underlying nature and might need a different approach in cognitive remediation.


Assuntos
Anorexia Nervosa/classificação , Bulimia/classificação , Senso de Coerência , Enquadramento Psicológico , Vômito/classificação , Adolescente , Adulto , Anorexia Nervosa/psicologia , Bulimia/psicologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Vômito/psicologia
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