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1.
J Int Neuropsychol Soc ; 28(9): 984-995, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34665083

RESUMEN

OBJECTIVE: Clinical neuropsychology has been slow in adopting novelties in psychometrics, statistics, and technology. Researchers have indicated that the stationary nature of clinical neuropsychology endangers its evidence-based character. In addition to a technological crisis, there may be a statistical crisis affecting clinical neuropsychology. That is, the frequentist null hypothesis significance testing framework remains the dominant approach in clinical practice, despite a recent surge in critique on this framework. While the Bayesian framework has been put forward as a viable alternative in psychology in general, the possibilities it offers to clinical neuropsychology have not received much attention. METHOD: In the current position paper, we discuss and reflect on the value of Bayesian methods for the advancement of evidence-based clinical neuropsychology. RESULTS: We aim to familiarize clinical neuropsychologists and neuropsychological researchers to Bayesian methods of inference and provide a clear rationale for why these methods are valuable for clinical neuropsychology. CONCLUSION: We argue that Bayesian methods allow for a more intuitive answer to our diagnostic questions and form a more solid foundation for sequential and adaptive diagnostic testing, representing uncertainty about patients' observed test scores and cognitive modeling of test results.


Asunto(s)
Neuropsicología , Teorema de Bayes , Humanos , Pruebas Neuropsicológicas , Neuropsicología/métodos , Psicometría
2.
Neurol Sci ; 43(11): 6349-6358, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35971043

RESUMEN

BACKGROUND AND PURPOSE: The Oxford Cognitive Screen is a stroke-specific screen to evaluate attention, executive functions, memory, praxis, language, and numeric cognition. It was originally validated in England for acute stroke patients. In this study, we examined the psychometric properties of the Dutch OCS (OCS-NL). METHODS: A total of 193 (99 acute stroke unit, 94 rehabilitation unit) patients were included in our study. A subset of patients (n = 128) completed a retest with the parallel version of the OCS-NL. RESULTS: First, we did not find evidence for a difference in prevalence of impairment between patients in the acute stroke versus rehabilitation unit on all but one of the subtests. For praxis, we observed a 14% lower prevalence of impairment in the rehabilitation than the acute stroke unit. Second, the parallel-form reliability ranged from weak to excellent across subtests. Third, in stroke patients below age 60, the OCS-NL had a 92% sensitivity relative to the MoCA, while the MoCA had a 55% sensitivity relative to the OCS-NL. Last, although left-hemispheric stroke patients performed worse on almost all MoCA subdomains, they performed similarly to right-hemispheric stroke patients on non-language domains on the OCS-NL. CONCLUSIONS: Our results suggest that the OCS-NL is a reliable cognitive screen that can be used in acute stroke and rehabilitation units. The OCS-NL may be more sensitive to detect cognitive impairment in young stroke patients and less likely to underestimate cognitive abilities in left-hemispheric stroke patients than the MoCA.


Asunto(s)
Trastornos del Conocimiento , Disfunción Cognitiva , Accidente Cerebrovascular , Humanos , Persona de Mediana Edad , Psicometría , Pruebas Neuropsicológicas , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/psicología , Reproducibilidad de los Resultados , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Sobrevivientes , Cognición , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/etiología
3.
Eur J Neurosci ; 53(8): 2713-2725, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33450082

RESUMEN

Temporal orienting of attention can affect multiple stages of processing to guide adaptive behaviour. We tested whether temporal expectation in different task contexts is compromised in individuals with Parkinson's disease (PD). In Experiment 1 two temporal-orienting tasks were used: a speeded task emphasizing motor preparation and a non-speeded task emphasizing perceptual discrimination using rapid serial visual presentation. In both tasks, auditory cues indicated the likelihood of a target appearing after a short or long interval. In the speeded-response task, participants used the cues to anticipate an easily detectable target stimulus. In the non-speeded perceptual-discrimination task, participants used the cues to help discriminate a target letter embedded in a stream of letters. Relative to healthy participants, participants with PD did not show altered temporal orienting effects in the speeded-response task. However, they were impaired in using temporal cues to improve perceptual discrimination. In Experiment 2, we tested whether the temporal-orienting deficits in the perceptual-discrimination task depended on the requirement to ignore temporally distracting stimuli. We replicated the impaired temporal orienting for perceptual discrimination in an independent group of individuals with PD, and showed the impairment was abolished when individuals were on their dopaminergic medication. In a task without any distracting letters, however, patients off or on medication benefited normally from temporal orienting cues. Our findings suggest that deficits in temporal orienting in individuals with PD interact with specific task demands, such as the requirement to select target from temporally competing distractors.


Asunto(s)
Enfermedad de Parkinson , Atención , Señales (Psicología) , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Tiempo de Reacción
4.
J Int Neuropsychol Soc ; 26(7): 668-678, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32223770

RESUMEN

OBJECTIVE: To diagnose egocentric neglect after stroke, the spatial bias of performance on cancellation tasks is typically compared to a single cutoff. This standard procedure relies on the assumption that the measurement error of cancellation performance does not depend on non-spatial impairments affecting the total number of cancelled targets. Here we assessed the impact of this assumption on false-positive diagnoses. METHOD: We estimated false positives by simulating cancellation data using a binomial model. Performance was summarised by the difference in left and right cancelled targets (R-L) and the Centre of Cancellation (CoC). Diagnosis was based on a fixed cutoff versus cutoffs adjusted for the total number of cancelled targets and on single test performance versus unanimous or proportional agreement across multiple tests. Finally, we compared the simulation findings to empirical cancellation data acquired from 651 stroke patients. RESULTS: Using a fixed cutoff, the rate of false positives depended on the total number of cancelled targets and ranged from 10% to 30% for R-L scores and from 10% to 90% for CoC scores. The rate of false positives increased even further when diagnosis was based on proportional agreement across multiple tests. Adjusted cutoffs and unanimous agreement across multiple tests were effective at controlling false positives. For empirical data, fixed versus adjusted cutoffs differ in estimation of neglect prevalence by 13%, and this difference was largest for patients with non-spatial impairments. CONCLUSIONS: Our findings demonstrate the importance of considering non-spatial impairments when diagnosing neglect based on cancellation performance.


Asunto(s)
Trastornos de la Percepción/diagnóstico , Anciano , Anciano de 80 o más Años , Atención , Reacciones Falso Positivas , Femenino , Lateralidad Funcional , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Accidente Cerebrovascular/fisiopatología
5.
Neuroimage ; 191: 216-224, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30771448

RESUMEN

Several computational models explain how symmetry might be detected and represented in the human brain. However, while there is an abundance of psychophysical studies on symmetry detection and several neural studies showing where and when symmetry is detected in the brain, important questions remain about how this detection happens and how symmetric patterns are represented. We studied the representation of (vertical) symmetry in regions of the ventral visual stream, using multi-voxel pattern analyses (MVPA) and functional connectivity analyses. Our results suggest that neural representations gradually change throughout the ventral visual stream, from very similar part-based representations for symmetrical and asymmetrical stimuli in V1 and V2, over increasingly different representations for symmetrical and asymmetrical stimuli which are nevertheless still part-based in both V3 and V4, to a more holistic representation for symmetrical compared to asymmetrical stimuli in high-level LOC. This change in representations is accompanied by increased communication between left and right retinotopic areas, evidenced by higher interhemispheric functional connectivity during symmetry perception in areas V2 and V4.


Asunto(s)
Reconocimiento Visual de Modelos/fisiología , Corteza Visual/fisiología , Vías Visuales/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto Joven
6.
Neuroimage ; 190: 289-302, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29885484

RESUMEN

Two hypotheses have been proposed about the etiology of neurodevelopmental learning disorders, such as dyslexia and dyscalculia: representation impairments and disrupted access to representations. We implemented a multi-method brain imaging approach to directly investigate these representation and access hypotheses in dyscalculia, a highly prevalent but understudied neurodevelopmental disorder in learning to calculate. We combined several magnetic resonance imaging methods and analyses, including univariate and multivariate analyses, functional and structural connectivity. Our sample comprised 24 adults with dyscalculia and 24 carefully matched controls. Results showed a clear deficit in the non-symbolic magnitude representations in parietal, temporal and frontal regions, as well as hyper-connectivity in visual brain regions in adults with dyscalculia. Dyscalculia in adults was thereby related to both impaired number representations and altered connectivity in the brain. We conclude that dyscalculia is related to impaired number representations as well as altered access to these representations.


Asunto(s)
Corteza Cerebral/fisiopatología , Conectoma , Discalculia/fisiopatología , Conceptos Matemáticos , Adolescente , Adulto , Corteza Cerebral/diagnóstico por imagen , Discalculia/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Adulto Joven
8.
J Neurosci ; 35(30): 10647-58, 2015 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-26224851

RESUMEN

Visuospatial attention allows us to select and act upon a subset of behaviorally relevant visual stimuli while ignoring distraction. Bundesen's theory of visual attention (TVA) (Bundesen, 1990) offers a quantitative analysis of the different facets of attention within a unitary model and provides a powerful analytic framework for understanding individual differences in attentional functions. Visuospatial attention is contingent upon large networks, distributed across both hemispheres, consisting of several cortical areas interconnected by long-association frontoparietal pathways, including three branches of the superior longitudinal fasciculus (SLF I-III) and the inferior fronto-occipital fasciculus (IFOF). Here we examine whether structural variability within human frontoparietal networks mediates differences in attention abilities as assessed by the TVA. Structural measures were based on spherical deconvolution and tractography-derived indices of tract volume and hindrance-modulated orientational anisotropy (HMOA). Individual differences in visual short-term memory (VSTM) were linked to variability in the microstructure (HMOA) of SLF II, SLF III, and IFOF within the right hemisphere. Moreover, VSTM and speed of information processing were linked to hemispheric lateralization within the IFOF. Differences in spatial bias were mediated by both variability in microstructure and volume of the right SLF II. Our data indicate that the microstructural and macrostrucutral organization of white matter pathways differentially contributes to both the anatomical lateralization of frontoparietal attentional networks and to individual differences in attentional functions. We conclude that individual differences in VSTM capacity, processing speed, and spatial bias, as assessed by TVA, link to variability in structural organization within frontoparietal pathways.


Asunto(s)
Atención/fisiología , Lóbulo Frontal/fisiología , Individualidad , Vías Nerviosas/fisiología , Lóbulo Parietal/fisiología , Percepción Visual/fisiología , Adulto , Mapeo Encefálico , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Adulto Joven
9.
J Neurosci ; 35(37): 12673-92, 2015 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-26377458

RESUMEN

Posterior cortical atrophy (PCA) is a rare focal neurodegenerative syndrome characterized by progressive visuoperceptual and visuospatial deficits, most often due to atypical Alzheimer's disease (AD). We applied insights from basic visual neuroscience to analyze 3D shape perception in humans affected by PCA. Thirteen PCA patients and 30 matched healthy controls participated, together with two patient control groups with diffuse Lewy body dementia (DLBD) and an amnestic-dominant phenotype of AD, respectively. The hierarchical study design consisted of 3D shape processing for 4 cues (shading, motion, texture, and binocular disparity) with corresponding 2D and elementary feature extraction control conditions. PCA and DLBD exhibited severe 3D shape-processing deficits and AD to a lesser degree. In PCA, deficient 3D shape-from-shading was associated with volume loss in the right posterior inferior temporal cortex. This region coincided with a region of functional activation during 3D shape-from-shading in healthy controls. In PCA patients who performed the same fMRI paradigm, response amplitude during 3D shape-from-shading was reduced in this region. Gray matter volume in this region also correlated with 3D shape-from-shading in AD. 3D shape-from-disparity in PCA was associated with volume loss slightly more anteriorly in posterior inferior temporal cortex as well as in ventral premotor cortex. The findings in right posterior inferior temporal cortex and right premotor cortex are consistent with neurophysiologically based models of the functional anatomy of 3D shape processing. However, in DLBD, 3D shape deficits rely on mechanisms distinct from inferior temporal structural integrity. SIGNIFICANCE STATEMENT: Posterior cortical atrophy (PCA) is a neurodegenerative syndrome characterized by progressive visuoperceptual dysfunction and most often an atypical presentation of Alzheimer's disease (AD) affecting the ventral and dorsal visual streams rather than the medial temporal system. We applied insights from fundamental visual neuroscience to analyze 3D shape perception in PCA. 3D shape-processing deficits were affected beyond what could be accounted for by lower-order processing deficits. For shading and disparity, this was related to volume loss in regions previously implicated in 3D shape processing in the intact human and nonhuman primate brain. Typical amnestic-dominant AD patients also exhibited 3D shape deficits. Advanced visual neuroscience provides insight into the pathogenesis of PCA that also bears relevance for vision in typical AD.


Asunto(s)
Corteza Cerebral/patología , Percepción de Forma/fisiología , Enfermedades Neurodegenerativas/fisiopatología , Anciano , Agnosia/fisiopatología , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/fisiopatología , Atrofia , Ceguera/etiología , Ceguera/fisiopatología , Mapeo Encefálico , Corteza Cerebral/fisiopatología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Enfermedad por Cuerpos de Lewy/patología , Enfermedad por Cuerpos de Lewy/fisiopatología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Percepción de Movimiento/fisiología , Corteza Motora/patología , Corteza Motora/fisiopatología , Enfermedades Neurodegenerativas/patología , Pruebas Neuropsicológicas , Tamaño de los Órganos , Tomografía de Emisión de Positrones , Lóbulo Temporal/patología , Lóbulo Temporal/fisiopatología
10.
Cereb Cortex ; 23(12): 2840-54, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22941718

RESUMEN

The intraparietal sulcus (IPS) is critical for resolving stimulus competition. Its activity is modulated depending on how competing stimuli are spatially configured. Lesions extending into IPS lead to selection deficits when stimuli are configured along a horizontal relative to a vertical or diagonal axis. Using functional magnetic resonance imaging, we examined whether the effect of configuration axis originates at the level of the sensory map in early visual cortex or at the level of the attentional priority map in IPS. In each trial, we presented 1 or 2 peripheral gratings in the upper right visual field and a central letter stream. Subjects performed either a peripheral orientation discrimination task or a central letter detection task. Left IPS activity was higher when peripheral stimuli were configured along the horizontal relative to the vertical axis, but only in peripheral attention conditions. The portions of extrastriate cortex that responded to the peripheral stimuli showed a similar interaction. Connectivity from superior parietal to extrastriate cortex was enhanced by adding a competing distracter during the peripheral attention task. The effect of the spatial configuration between competing stimuli originates at the level of the attentional priority map in IPS rather than the visual sensory map.


Asunto(s)
Atención/fisiología , Red Nerviosa/fisiología , Lóbulo Parietal/fisiología , Percepción Espacial/fisiología , Corteza Visual/fisiología , Adulto , Mapeo Encefálico , Discriminación en Psicología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Estimulación Luminosa , Adulto Joven
11.
Clin Neuropsychol ; 38(3): 588-611, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-37480233

RESUMEN

Objective: Although neurocognitive disorders (NCD) are common post-stroke, many populations do not have adapted cognitive screens and cut-offs. We therefore reviewed the appropriateness of the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) and Oxford Cognitive Screen (OCS) for diagnosing NCD in culturally diverse stroke populations. Method: Using an extensive search string, diagnostic accuracy studies for MMSE, MoCA and OCS in the stroke population were retrieved from four databases. We compared translations and adaptations, adjustments in scores and cut-offs, and their diagnostic accuracy. Results: The search resulted in 28 MMSE, 39 MoCA and 5 OCS-studies in 13 western, educated, industrialized, rich and democratic (WEIRD) and 4 other countries. There was a lack of studies on South-American, African, and non-Chinese-Asian populations. All three tests needed adaptation for less WEIRD populations and populations with languages with non-Latin features. Optimal MMSE and OCS subtest cut-offs were similar across WEIRD and less WEIRD populations, whereas optimal MoCA cut-offs appeared lower for less WEIRD populations. The use of adjusted scores resulted in different optimal cut-offs or similar cut-offs with better accuracy. Conclusions: MoCA, MMSE and OCS are promising tools for diagnosing post-stroke-NCD. For culturally diverse populations, translation, adaptation and adjusted scores or cut-offs are necessary for diagnostic accuracy. Available studies report scarcely about their sample's cultural background and there is a lack of diagnostic accuracy studies in less WEIRD or culturally diverse populations. Future studies should report more cultural characteristics of their sample to provide better insight into the tests' accuracy in culturally diverse populations.


Asunto(s)
Trastornos del Conocimiento , Disfunción Cognitiva , Accidente Cerebrovascular , Humanos , Disfunción Cognitiva/diagnóstico , Pruebas Neuropsicológicas , Accidente Cerebrovascular/complicaciones , Trastornos del Conocimiento/diagnóstico , Trastornos Neurocognitivos
12.
Jpn J Ophthalmol ; 68(3): 183-191, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38598144

RESUMEN

PURPOSE: To assess the impact of glaucoma on perceiving three-dimensional (3D) shapes based on monocular depth cues. STUDY DESIGN: Clinical observational study. METHODS: Twenty glaucoma patients, subjected to binocular visual-field sensitivity (binocular-VFS) tests using a Humphrey Visual Field Analyzer, and 20 age-matched healthy volunteers, underwent two tasks: identifying the nearest vertex of a 3D shape using monocular shading (3D-SfS), texture (3D-SfT), or motion (3D-SfM) cues, and distinguishing elementary one-dimensional (1D) features of these cues. The association of the visual-field index (VFI) of binocular-VFS with 3D shape perception in glaucoma patients was also examined. RESULTS: Glaucoma patients demonstrated reduced accuracy in distinguishing 1D luminance brightness and a larger "error-in-depth" between the perceived and actual depths for 3D-SfM and 3D-SfS compared to healthy volunteers. Six glaucoma patients with a 100% VFI for binocular-VFS exhibited a similar error-in-depth to the other fourteen glaucoma patients; they had a larger error-in-depth for 3D-SfM compared to healthy volunteers. No correlation between the error-in-depth values and the VFI values of binocular-VFS was observed. CONCLUSIONS: The 3D shape perception in glaucoma patients varies based on the depth cue's characteristics. Impaired 1D discrimination and larger thresholds for 3D-SfM in glaucoma patients with a 100% VFI for binocular-VFS indicate more pronounced perceptual deficits of lower-level elementary features for 3D-SfS and higher-level visual processing of 3D shapes for 3D-SfM. The effects of the location and degree of binocular visual-field defects on 3D shape perception remain to be elucidated. Our research provides insights into the 3D shape extraction mechanism in glaucoma.


Asunto(s)
Señales (Psicología) , Percepción de Profundidad , Glaucoma , Visión Binocular , Visión Monocular , Campos Visuales , Humanos , Masculino , Femenino , Percepción de Profundidad/fisiología , Visión Binocular/fisiología , Campos Visuales/fisiología , Persona de Mediana Edad , Anciano , Glaucoma/fisiopatología , Glaucoma/diagnóstico , Visión Monocular/fisiología , Pruebas del Campo Visual , Presión Intraocular/fisiología , Percepción de Forma/fisiología , Adulto
13.
Clin Neuropsychol ; 38(2): 377-411, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37291083

RESUMEN

Objective: Sensory hypersensitivity is common after acquired brain injury. Since appropriate diagnostic tools are lacking, these complaints are overlooked by clinicians and available literature is limited to light and noise hypersensitivity after concussion. This study aimed to investigate the prevalence of sensory hypersensitivity in other modalities and after other types of brain injury. Method: We developed the Multi-Modal Evaluation of Sensory Sensitivity (MESSY), a patient-friendly questionnaire that assesses sensory sensitivity across multiple sensory modalities. 818 neurotypical adults (mean age = 49; 244 male) and 341 chronic acquired brain injury patients (including stroke, traumatic brain injury, and brain tumour patients) (mean age = 56; 126 male) completed the MESSY online. Results: The MESSY had a high validity and reliability in neurotypical adults. Post-injury sensory hypersensitivity (examined using open-ended questions) was reported by 76% of the stroke patients, 89% of the traumatic brain injury patients, and 82% of the brain tumour patients. These complaints occurred across all modalities with multisensory, visual, and auditory hypersensitivity being the most prevalent. Patients with post-injury sensory hypersensitivity reported a higher sensory sensitivity severity on the multiple-choice items of the MESSY as compared to neurotypical adults and acquired brain injury patients without post-injury sensory hypersensitivity (across all sensory modalities) (effect sizes (partial eta squared) ranged from .06 to .22). Conclusions: These results show that sensory hypersensitivity is prevalent after different types of acquired brain injury as well as across several sensory modalities. The MESSY can improve recognition of these symptoms and facilitate further research.


Asunto(s)
Conmoción Encefálica , Lesiones Traumáticas del Encéfalo , Neoplasias Encefálicas , Accidente Cerebrovascular , Adulto , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Pruebas Neuropsicológicas , Conmoción Encefálica/diagnóstico
14.
Appl Neuropsychol Adult ; : 1-9, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38976764

RESUMEN

Memory impairment imposes a great burden on stroke patients and can be divided into Objective Memory Problems (OMPs) and Subjective Memory Complaints (SMCs). Studies have shown that these do not always co-occur. Possibly, the gap between SMCs and OMPs can be bridged when using a more ecologically valid memory test and considering the impact of other common stroke symptoms such as sensory hypersensitivity (SHS) and fatigue. In the present study, we applied Virtual Reality (VR) to create a sensory-rich environment with real-life stimuli. Memory performance was tested with the 15-Verbal Word Learning Test (VLT). Furthermore, we assessed SMCs (Everyday Memory Questionnaire), and the levels of SHS (Multi-Modal Evaluation of Sensory Sensitivity) and fatigue in the previous month. 31 chronic stroke patients and 32 healthy controls participated. The results showed that participants' memory performance decreased in a sensory-rich compared to a neutral environment. This decrease did not significantly differ between the groups. Interestingly, fatigue and SHS are related to the level of SMC in stroke patients but no such evidence was found in healthy controls. Last, for stroke patients, we found a significant negative correlation between SMCs and memory performance in a sensory-rich environment, but not in a neutral environment. In conclusion, our study implicates that in stroke patients, fatigue and SHS are related to SMCs and that using a sensory-rich VR environment might be a more ecologically valid way to objectify SMCs. However, interpretative caution is warranted due to the absence of sex and age-matched controls and potential selection bias.

15.
Neuroimage ; 67: 257-72, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23201362

RESUMEN

Selection and reorienting are two fundamental aspects of spatial attention. By means of event-related fMRI in a total of 26 subjects, we localized these two processes within a same experiment applying a probabilistic cytoarchitectonic reference frame. In a classical spatial cueing paradigm, the target was presented at the cued location either alone (60% of trials) or in combination with a contralateral distracter ('competition trials', 20% of trials), or at a location opposite to the cued location ('invalidly cued trials', 20% of trials). In a sensory control experiment we differentiated between the attentional and the sensory effects of the distracter. In areas hIP1 and hIP3, competition trials exerted a significantly stronger attentional effect than invalidity trials. Conversely, area PF in the right hemisphere showed an invalidity effect in the absence of competition effect. A third type of response was found in areas PFm and PGa which showed both an invalidity and a competition effect. The combined study of selection and reorienting using a cytoarchitectonic reference frame enabled us to resolve the wide between-study variance in temporoparietal coordinates associated with the invalidity effect. Furthermore, the study demonstrated within a same experiment a functional dissociation between reorienting and selection in parietal cortex.


Asunto(s)
Atención/fisiología , Red Nerviosa/anatomía & histología , Red Nerviosa/fisiología , Orientación/fisiología , Lóbulo Parietal/anatomía & histología , Lóbulo Parietal/fisiología , Percepción Espacial/fisiología , Adulto , Mapeo Encefálico , Femenino , Humanos , Masculino , Adulto Joven
16.
Artículo en Inglés | MEDLINE | ID: mdl-37860978

RESUMEN

Feature-based attention allows to efficiently guide attention to relevant information in the visual scene, but unambiguous empirical evidence on age-related effects is still limited. In this study, young and older participants performed a two-alternative forced choice task in which a response was selected based on a task-relevant number (=target) presented alone or with a task-irrelevant letter (=neutral distracter) or number (=compatible/incompatible distracter). Participants were required to select the target based on color. To compare the behavioral interference of the distracters between the age groups, data were modeled with a hierarchical drift-diffusion model. The results revealed that decreases in the rate at which information was collected in the conditions with versus without a distracter were more pronounced in the older than young age group when the distracter was compatible or incompatible. Our findings are consistent with an age-related decline in the ability to filter out distracters based on features.

17.
Appl Neuropsychol Adult ; : 1-17, 2023 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-37210673

RESUMEN

Many activities in daily life rely on the ability to continuously keep attention on task requirements. Patients with acquired brain injury often suffer from deficits in sustained attention that impact quality of life and complicate rehabilitation. The sustained attention to response task (SART) is a commonly used go/no-go task in the assessment of sustained attention. However, its feasibility for patients with acquired brain injury could be questioned considering deficits in alphanumerical processing following brain damage. We investigated whether a SART with sinusoidal gratings instead of digits can be used to assess sustained attention. The Gratings SART and Digits SART were administered in a random and fixed sequence to 48 cognitively healthy participants. Performance of the neurotypical individuals on the random and fixed Gratings SART was only moderately different from and correlated with performance on the random and fixed Digits SART. As a proof of concept, the SARTs were also administered to 11 cases with acquired brain injury. Performance in the random and fixed variants of both the Gratings SART and Digits SART was sensitive to cognitive impairments of cases with acquired brain injury. In conclusion, the SART with sinusoidal gratings holds promise as a tool to (re-)assess sustained attention in clinical practice. Further research is critical to investigate whether its performance accurately predicts sustained attention in daily life since we failed to find a significant correlation between performance on any of the SARTs and a self-reported measure of sustained attention.

18.
J Neuropsychol ; 17(1): 1-31, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35773750

RESUMEN

Patients with acquired brain injury frequently report experiencing sensory stimuli as abnormally under- (sensory hyposensitivity) or overwhelming (sensory hypersensitivity). Although they can negatively impact daily functioning, these symptoms are poorly understood. To provide an overview of the current evidence on atypical sensory sensitivity after acquired brain injury, we conducted a systematic literature review. The primary aim of the review was to investigate the behavioural and neural mechanisms that are associated with self-reported sensory sensitivity. Studies were included when they studied sensory sensitivity in acquired brain injury populations, and excluded when they were not written in English, consisted of non-empirical research, did not study human subjects, studied pain, related sensory sensitivity to peripheral injury or studied patients with a neurodegenerative disorder, meningitis, encephalitis or a brain tumour. The Web of Science, PubMed and Scopus databases were searched for appropriate studies. A qualitative synthesis of the results of the 81 studies that were included suggests that abnormal sensory thresholds and a reduced information processing speed are candidate behavioural mechanisms of atypical subjective sensory sensitivity after acquired brain injury. Furthermore, there was evidence for an association between subjective sensory sensitivity and structural grey or white matter abnormalities, and to functional abnormalities in sensory cortices. However, further research is needed to explore the causation of atypical sensory sensitivity. In addition, there is a need for the development of adequate diagnostic tools. This can significantly advance the quantity and quality of research on the prevalence, aetiology, prognosis and treatment of these symptoms.


Asunto(s)
Lesiones Encefálicas , Trastornos de la Sensación , Humanos , Lesiones Encefálicas/complicaciones , Trastornos de la Sensación/etiología
19.
Neuropsychologia ; 184: 108564, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37068585

RESUMEN

It is commonly asserted that MRI-derived lesion masks outperform CT-derived lesion masks in lesion-mapping analysis. However, no quantitative analysis has been conducted to support or refute this claim. This study reports an objective comparison of lesion-mapping analyses based on CT- and MRI-derived lesion masks to clarify how input imaging type may ultimately impact analysis results. Routine CT and MRI data were collected from 85 acute stroke survivors. These data were employed to create binarized lesion masks and conduct lesion-mapping analyses on simulated behavioral data. Following standard lesion-mapping analysis methodology, each voxel or region of interest (ROI) were considered as the underlying "target" within CT and MRI data independently. The resulting thresholded z-maps were compared between matched CT- and MRI-based analyses. Paired MRI- and CT-derived lesion masks were found to exhibit significant variance in location, overlap, and size. In ROI-level simulations, both CT and MRI-derived analyses yielded low Dice similarity coefficients, but CT analyses yielded a significantly higher proportion of results which overlapped with target ROIs. In single-voxel simulations, MRI-based lesion mapping was able to include more voxels than CT-based analyses, but CT-based analysis results were closer to the underlying target voxel. Simulated lesion-symptom mapping results yielded by paired CT and MRI lesion-symptom mapping analyses demonstrated moderate agreement in terms of Dice coefficient when systematic differences in cluster size and lesion overlay are considered. Overall, these results suggest that CT and MR-derived lesion-symptom mapping results do not reliably differ in accuracy. This finding is critically important as it suggests that future studies can employ CT-derived lesion masks if these scans are available within the appropriate time-window.


Asunto(s)
Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/patología , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X
20.
Neuro Oncol ; 25(8): 1395-1414, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-36809489

RESUMEN

BACKGROUND: Cognitive functioning is increasingly assessed as a secondary outcome in neuro-oncological trials. However, which cognitive domains or tests to assess, remains debatable. In this meta-analysis, we aimed to elucidate the longer-term test-specific cognitive outcomes in adult glioma patients. METHODS: A systematic search yielded 7098 articles for screening. To investigate cognitive changes in glioma patients and differences between patients and controls 1-year follow-up, random-effects meta-analyses were conducted per cognitive test, separately for studies with a longitudinal and cross-sectional design. A meta-regression analysis with a moderator for interval testing (additional cognitive testing between baseline and 1-year posttreatment) was performed to investigate the impact of practice in longitudinal designs. RESULTS: Eighty-three studies were reviewed, of which 37 were analyzed in the meta-analysis, involving 4078 patients. In longitudinal designs, semantic fluency was the most sensitive test to detect cognitive decline over time. Cognitive performance on mini-mental state exam (MMSE), digit span forward, phonemic and semantic fluency declined over time in patients who had no interval testing. In cross-sectional studies, patients performed worse than controls on the MMSE, digit span backward, semantic fluency, Stroop speed interference task, trail-making test B, and finger tapping. CONCLUSIONS: Cognitive performance of glioma patients 1 year after treatment is significantly lower compared to the norm, with specific tests potentially being more sensitive. Cognitive decline over time occurs as well, but can easily be overlooked in longitudinal designs due to practice effects (as a result of interval testing). It is warranted to sufficiently correct for practice effects in future longitudinal trials.


Asunto(s)
Trastornos del Conocimiento , Glioma , Humanos , Adulto , Trastornos del Conocimiento/diagnóstico , Estudios Transversales , Cognición , Pruebas Neuropsicológicas , Glioma/complicaciones , Glioma/terapia , Terapia Combinada
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