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1.
Hum Brain Mapp ; 45(1): e26549, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38224538

RESUMO

The ability to identify and resolve conflicts between standard, well-trained behaviors and behaviors required by the current context is an essential feature of cognitive control. To date, no consensus has been reached on the brain mechanisms involved in exerting such control: while some studies identified diverse patterns of activity across different conflicts, other studies reported common resources across conflict tasks or even across simple tasks devoid of the conflict component. The latter reports attributed the entire activity observed in the presence of conflict to longer time spent on the task (i.e., to the so-called time-on-task effects). Here, we used an extended Multi-Source Interference Task (MSIT) which combines Simon and flanker types of interference to determine shared and conflict-specific mechanisms of conflict resolution in fMRI and their separability from the time-on-task effects. Large portions of the activity in the dorsal attention network and decreases of activity in the default mode network were shared across the tasks and scaled in parallel with increasing reaction times. Importantly, the activity in the sensory and sensorimotor cortices, as well as in the posterior medial frontal cortex (pMFC) - a key region implicated in conflict processing - could not be exhaustively explained by the time-on-task effects.


Assuntos
Encéfalo , Conflito Psicológico , Humanos , Encéfalo/diagnóstico por imagem , Tempo de Reação , Lobo Frontal , Mapeamento Encefálico
2.
Genes (Basel) ; 14(12)2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38136995

RESUMO

Noonan syndrome (NS) is one of the most common genetic conditions inherited mostly in an autosomal dominant manner with vast heterogeneity in clinical and genetic features. Patients with NS might have speech disturbances, memory and attention deficits, limitations in daily functioning, and decreased overall intelligence. Here, 34 patients with Noonan syndrome and 23 healthy controls were enrolled in a study involving gray and white matter volume evaluation using voxel-based morphometry (VBM), white matter connectivity measurements using diffusion tensor imaging (DTI), and resting-state functional magnetic resonance imaging (rs-fMRI). Fractional anisotropy (FA) and mean diffusivity (MD) probability distributions were calculated. Cognitive abilities were assessed using the Stanford Binet Intelligence Scales. Reductions in white matter connectivity were detected using DTI in NS patients. The rs-fMRI revealed hyper-connectivity in NS patients between the sensorimotor network and language network and between the sensorimotor network and salience network in comparison to healthy controls. NS patients exhibited decreased verbal and nonverbal IQ compared to healthy controls. The assessment of the microstructural alterations of white matter as well as the resting-state functional connectivity (rsFC) analysis in patients with NS may shed light on the mechanisms responsible for cognitive and neurofunctional impairments.


Assuntos
Imagem de Tensor de Difusão , Síndrome de Noonan , Humanos , Imagem de Tensor de Difusão/métodos , Proteínas Proto-Oncogênicas p21(ras) , Imageamento por Ressonância Magnética , Síndrome de Noonan/genética , Cognição , Proteínas Quinases Ativadas por Mitógeno , Transdução de Sinais
3.
Sci Rep ; 13(1): 18417, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891242

RESUMO

Previous studies indicate changes in neurotransmission along the auditory pathway in subjective tinnitus. Most authors, however, investigated brain regions including the primary auditory cortex, whose physiology can be affected by concurrent hearing deficits. In the present MR spectroscopy study we assumed increased levels of glutamate and glutamine (Glx), and other Central Nervous System metabolites in the temporal lobe outside the primary auditory cortex, in a region involved in conscious auditory perception and memory. We studied 52 participants with unilateral (n = 24) and bilateral (n = 28) tinnitus, and a control group without tinnitus (n = 25), all with no severe hearing losses and a similar hearing profile. None of the metabolite levels in the temporal regions of interest were found related to tinnitus status or laterality. Unexpectedly, we found a tendency of increased concentration of Glx in the control left medial frontal region in bilateral vs unilateral tinnitus. Slightly elevated depressive and anxiety symptoms were also shown in participants with tinnitus, as compared to healthy individuals, with the bilateral tinnitus group marginally more affected. We discuss no apparent effect in the temporal lobes, as well as the role of frontal brain areas, with respect to hearing loss, attention and psychological well-being in chronic tinnitus. We furthermore elaborate on the design-related and technical obstacles of MR spectroscopy.


Assuntos
Córtex Auditivo , Perda Auditiva , Zumbido , Humanos , Zumbido/diagnóstico , Córtex Auditivo/diagnóstico por imagem , Córtex Auditivo/metabolismo , Audição , Espectroscopia de Ressonância Magnética , Perda Auditiva/metabolismo
4.
Neurol Neurochir Pol ; 57(5): 430-437, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37706668

RESUMO

INTRODUCTION: The main aim of our study was to compare diffusion tensor imaging (DTI) parameters in patients with myotonic dystrophy types 1 and 2 (DM1 and DM2). CLINICAL RATIONALE FOR THE STUDY: To ascertain whether DTI could be used to assess the integrity of white matter tracts in the brain and identify any abnormalities or disruptions in connectivity between different brain regions in patients with DM. By providing a more detailed understanding of the structural changes in the brain associated with DM, could DTI potentially be used to develop more effective treatments for the cognitive and neurological symptoms of the disorder? MATERIAL AND METHODS: We retrospectively compared MRI scans of 19 patients with DM1 to those of 23 healthy, matched controls, and of 16 patients with DM2 to those of 20 healthy, matched controls, and finally compared the DM1 and DM2 samples. Fraction anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) values were assessed using Tract Based Spatial Statistics (TBSS). RESULTS: In patients with DM1, a statistically significant decrease in the values of the FA parameter was revealed in 45/48 white matter tracts compared to patients with DM2. There was no statistically significant decrease in the values of the FA parameter in patients with DM2 compared to DM1. The values of MD and RD were significantly higher in 47 tracts in DM1 patients compared to DM2 patients. AD values were significantly higher in all 48 tracts in DM1 patients compared to DM2 patients. There were no tracts with increased MD, AD, or RD values in DM2 patients compared to DM1. CONCLUSIONS: Our results indicate diffuse disintegration of white matter pathways in DM patients, especially in the DM1 group. The damage to all types of fibres (association, commissural, and projection) may explain the diversity of clinical symptoms, which were more severe in the DM1 group of patients than in the DM2 group. CLINICAL IMPLICATIONS: DTI in patients with DM may help us to understand the neural mechanisms underlying brain involvement during the disease. In future, it may help to identify biomarkers for disease progression and treatment response.


Assuntos
Distrofia Miotônica , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Distrofia Miotônica/diagnóstico por imagem , Estudos Retrospectivos , Encéfalo/diagnóstico por imagem
5.
Brain Lang ; 244: 105304, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37481794

RESUMO

From birth, we perceive speech by hearing and seeing people talk. In adults cortical representations of visual speech are processed in the putative temporal visual speech area (TVSA), but it remains unknown how these representations develop. We measured infants' cortical responses to silent visual syllables and non-communicative mouth movements using functional Near-Infrared Spectroscopy. Our results indicate that cortical specialisation for visual speech may emerge during infancy. The putative TVSA was active to both visual syllables and gurning around 5 months of age, and more active to gurning than to visual syllables around 10 months of age. Multivariate pattern analysis classification of distinct cortical responses to visual speech and gurning was successful at 10, but not at 5 months of age. These findings imply that cortical representations of visual speech change between 5 and 10 months of age, showing that the putative TVSA is initially broadly tuned and becomes selective with age.


Assuntos
Percepção da Fala , Adulto , Humanos , Lactente , Percepção da Fala/fisiologia , Estimulação Acústica/métodos , Audição , Estimulação Luminosa/métodos
6.
Brain Topogr ; 36(4): 459-475, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37171657

RESUMO

In adults, the integration of audiovisual speech elicits specific higher (super-additive) or lower (sub-additive) cortical responses when compared to the responses to unisensory stimuli. Although there is evidence that the fronto-temporal network is active during perception of audiovisual speech in infancy, the development of fronto-temporal responses to audiovisual integration remains unknown. In the current study, 5-month-olds and 10-month-olds watched bimodal (audiovisual) and alternating unimodal (auditory + visual) syllables. In this context we use alternating unimodal to denote alternating auditory and visual syllables that are perceived as separate syllables by adults. Using fNIRS we measured responses over large cortical areas including the inferior frontal and superior temporal regions. We identified channels showing different responses to bimodal than alternating unimodal condition and used multivariate pattern analysis (MVPA) to decode patterns of cortical responses to bimodal (audiovisual) and alternating unimodal (auditory + visual) speech. Results showed that in both age groups integration elicits cortical responses consistent with both super- and sub-additive responses in the fronto-temporal cortex. The univariate analyses revealed that between 5 and 10 months spatial distribution of these responses becomes increasingly focal. MVPA correctly classified responses at 5 months, with key input from channels located in the inferior frontal and superior temporal channels of the right hemisphere. However, MVPA classification was not successful at 10 months, suggesting a potential cortical re-organisation of audiovisual speech perception at this age. These results show the complex and non-gradual development of the cortical responses to integration of congruent audiovisual speech in infancy.


Assuntos
Percepção da Fala , Percepção Visual , Adulto , Humanos , Lactente , Percepção Visual/fisiologia , Fala/fisiologia , Percepção da Fala/fisiologia , Lobo Temporal , Percepção Auditiva/fisiologia , Estimulação Acústica , Estimulação Luminosa
7.
J Deaf Stud Deaf Educ ; 28(3): 288-299, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-36951492

RESUMO

Previous studies have suggested that parents may support the development of theory of mind (ToM) in their child by talking about mental states (mental state talk; MST). However, MST has not been sufficiently explored in deaf children with cochlear implants (CIs). This study investigated ToM and availability of parental MST in deaf children with CIs (n = 39, Mage = 62.92, SD = 15.23) in comparison with their peers with typical hearing (TH; n = 52, Mage = 52.48, SD = 1.07). MST was measured during shared storybook reading. Parents' narratives were coded for cognitive, emotional, literal, and non-mental references. ToM was measured with a parental questionnaire. Children with CIs had lower ToM scores than their peers with TH, and their parents used more literal references during shared storybook reading. There were no significant differences in the frequencies of cognitive and emotional references between groups. Parental emotional references contributed positively to children's ToM scores when controlling for the child's age and receptive grammar only in the CI group. These results indicated some distinctive features in parents of deaf children with CIs' MST and highlighted the role of MST in the development of ToM abilities in this group.


Assuntos
Implante Coclear , Implantes Cocleares , Teoria da Mente , Criança , Humanos , Pais , Grupo Associado
8.
Sci Rep ; 13(1): 4127, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36914701

RESUMO

The widespread ubiquity of hate speech affects people's attitudes and behavior. Exposure to hate speech can lead to prejudice, dehumanization, and lack of empathy towards members of outgroups. However, the impact of exposure to hate speech on empathy and propensity to attribute mental states to others has never been directly tested empirically. In this fMRI study, we examine the effects of exposure to hate speech on neural mechanisms of empathy towards ingroup (Poles) versus outgroup members (Arabs). Thirty healthy young adults were randomly assigned to 2 groups: hateful and neutral. During the fMRI study, they were initially exposed to hateful or neutral comments and subsequently to narratives depicting Poles and Arabs in pain. Using whole-brain and region of interest analysis, we showed that exposure to derogatory language about migrants attenuates the brain response to someone else's pain in the right temporal parietal junction (rTPJ), irrespective of group membership (Poles or Arabs). Given that rTPJ is associated with processes relevant to perspective-taking, its reduced activity might be related to a decreased propensity to take the psychological perspective of others. This finding suggests that hate speech affects human functioning beyond intergroup relations.


Assuntos
Ódio , Fala , Adulto Jovem , Humanos , Empatia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Dor/psicologia
9.
Int J Lang Commun Disord ; 58(2): 256-269, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36098626

RESUMO

BACKGROUND: Aphasia is often accompanied by impairment of non-language cognitive functions. Assessment of cognitive capacity in people with aphasia (PWA) with standard neuropsychological methods may be problematic due to their language difficulties. Numerous experimental studies indicate that P300 may be considered as an index of cognitive capacity in both healthy and clinical samples. Accordingly, the measurement of event-related potentials enables the investigation of behaviourally non-observable mental processes underlying the cognitive functions that are assessed with neuropsychological tests. AIMS: To investigate in PWA the relationship between P300 parameters and cognitive function efficiency measured with neuropsychological methods. METHODS & PROCEDURES: A total of 25 PWA after left-hemispheric stroke participated in the study. Electrophysiological (EEG) signals were recorded during the performance of a visual Go-No Go task. P300 was identified on nine electrodes, which were then pooled in three lines: left (F3, C3, P3), central (Fz, Cz, Pz) and right (F4, C4, P4). The neuropsychological assessment of cognitive functions included mental speed, short-term memory, divided attention, executive functions, auditory language comprehension and expression. OUTCOMES & RESULTS: P300 latency correlated with indices of several cognitive functions: temporal resolution, psychomotor speed, spatial short-term memory, planning, word and sentence comprehension, as well as verbal fluency. Shorter P300 latencies were accompanied by greater efficiency of the abovementioned functions. In contrast, significant correlations between P300 amplitudes and cognitive measures were fragmentary. CONCLUSIONS & IMPLICATIONS: In PWA, P300 latency might be related to cognitive functioning, especially to measures that rely heavily on the speed of information processing. However, P300 seems to be unrelated to more complex cognitive functions. P300 latency may be used as a neurophysiological correlate of cognitive efficiency in PWA and might have potential applications in monitoring the effects of therapeutic interventions in this patient group. WHAT THIS PAPER ADDS: What is already known on the subject P300 parameters have been reported to be associated with cognitive performance in both healthy individuals and clinical groups (e.g., patients with Alzheimer's disease). Previous studies show that the presence of P300 at the early post-stroke stage may be a predictor of better recovery of comprehension in PWA. What this paper adds to existing knowledge Our results show for the first time that P300 may be used as a neurophysiological correlate of cognitive efficiency in PWA. In our study, P300 latency was associated with several languages and non-language cognitive functions, especially with those whose effectiveness depends mainly on processing speed. In PWA, shorter latency corresponded to more efficient cognitive functioning. What are the potential or actual clinical implications of this work? P300 measurement may be potentially useful in assessing the efficiency of certain cognitive functions in PWA. It may be also used to monitor the recovery process of PWA and to verify the effects of therapeutic interventions.


Assuntos
Afasia , Acidente Vascular Cerebral , Humanos , Afasia/diagnóstico , Afasia/etiologia , Cognição , Função Executiva , Potenciais Evocados , Compreensão , Acidente Vascular Cerebral/complicações , Testes Neuropsicológicos
10.
Soc Neurosci ; 17(5): 428-440, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36309870

RESUMO

Mentalizing is the key socio-cognitive ability. Its heterogeneous structure may result from a variety of forms of mental state inference, which may be based on lower-level processing of cues encoded in the observable behavior of others, or rather involve higher-level computations aimed at understanding another person's perspective. Here we aimed to investigate the representational content of the brain regions engaged in mentalizing. To this end, 61 healthy adults took part in an fMRI study. We explored ROI activity patterns associated with five well-recognized ToM tasks that induce either decoding of mental states from motion kinematics or belief-reasoning. By using multivariate representational similarity analysis, we examined whether these examples of lower- and higher-level forms of social inference induced common or distinct patterns of brain activity. Distinct patterns of brain activity related to decoding of mental states from motion kinematics and belief-reasoning were found in lTPJp and the left IFG, but not the rTPJp. This may indicate that rTPJp supports a general mechanism for the representation of mental states. The divergent patterns of activation in lTPJp and frontal areas likely reflect differences in the degree of involvement of cognitive functions which support the basic mentalizing processes engaged by the two task groups.


Assuntos
Mentalização , Teoria da Mente , Adulto , Humanos , Mapeamento Encefálico , Teoria da Mente/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Imageamento por Ressonância Magnética
11.
Sci Rep ; 12(1): 15933, 2022 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-36153359

RESUMO

The study aimed to determine the relationship between the millisecond timing, measured by visual temporal order threshold (TOT), i.e. a minimum gap between two successive stimuli necessary to judge a before-after relation, and resting-state fMRI functional connectivity (rsFC). We assume that the TOT reflects a relatively stable feature of local internal state networks and is associated with rsFC of the temporal parietal junction (TPJ). Sixty five healthy young adults underwent the visual TOT, fluid intelligence (Gf) and an eyes-open resting-state fMRI examination. After controlling for the influence of gender, the higher the TOT, the stronger was the left TPJ's rsFC with the left postcentral and the right precentral gyri, bilateral putamen and the right supplementary motor area. When the effects of Gf and TOT × Gf interaction were additionally controlled, the TOT-left TPJ's rsFC relationship survived for almost all above regions with the exception of the left and right putamen. This is the first study demonstrating that visual TOT is associated with rsFC between the areas involved both in sub-second timing and motor control. Current outcomes indicate that the local neural networks are prepared to process brief, rapidly presented, consecutive events, even in the absence of such stimulation.


Assuntos
Imageamento por Ressonância Magnética , Córtex Motor , Humanos , Inteligência , Percepção Visual , Adulto Jovem
12.
Front Neurosci ; 16: 842420, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360180

RESUMO

For the analysis of simultaneous EEG-fMRI recordings, it is vital to use effective artifact removal tools. This applies in particular to the ballistocardiogram (BCG) artifact which is difficult to remove without distorting signals of interest related to brain activity. Here, we documented the use of surrogate source models to separate the artifact-related signals from brain signals with minimal distortion of the brain activity of interest. The artifact topographies used for surrogate separation were created automatically using principal components analysis (PCA-S) or by manual selection of artifact components utilizing independent components analysis (ICA-S). Using real resting-state data from 55 subjects superimposed with simulated auditory evoked potentials (AEP), both approaches were compared with three established BCG artifact removal methods: Blind Source Separation (BSS), Optimal Basis Set (OBS), and a mixture of both (OBS-ICA). Each method was evaluated for its applicability for ERP and source analysis using the following criteria: the number of events surviving artifact threshold scans, signal-to-noise ratio (SNR), error of source localization, and signal variance explained by the dipolar model. Using these criteria, PCA-S and ICA-S fared best overall, with highly significant differences to the established methods, especially in source localization. The PCA-S approach was also applied to a single subject Berger experiment performed in the MRI scanner. Overall, the removal of BCG artifacts by the surrogate methods provides a substantial improvement for the analysis of simultaneous EEG-fMRI data compared to the established methods.

13.
Psychiatr Pol ; 56(5): 1049-1059, 2022 Oct 31.
Artigo em Inglês, Polonês | MEDLINE | ID: mdl-37074856

RESUMO

OBJECTIVES: Goal: to evaluate changes in the grey matter volume using the VBM method in a group of adolescents with ASD, who met the criteria for Asperger's Syndrome. METHODS: Material and methods: Morphometric evaluations based on Voxel Based Morphometry (VBM) were performed on 37 male adolescents aged 12 to 19 (M = 14.3 ± 2.0), with autism spectrum disorders, who met the DSM-IV-TR criteria for Asperger's Syndrome and 15 neurotypical adolescents matched by age. Significance was set at p<0.007 without FWE correction and p<0.05 with FWE correction. RESULTS: Results: the decrease in the volume of the grey matter was observed in ASD group including the pre- and postcentral gyrus, the superior and middle frontal gyrus, the inferior and superior parietal lobule, the praecuneus, the anterior and posterior cingulate cortex, the fusiform gyrus, the parahippocampal gyrus, the lingual gyrus, the middle occipital region, the cuneus and the angular gyrus, the regions of calcarine sulcus and the cerebellum. The majority of changes was localized bilaterally. CONCLUSIONS: Conclusions: the decrease in the volume of grey matter observed in ASD group can be related functionally with the characteristics of deficits observed in autism spectrum disorders which highlights the role of abnormal organization of numerous CNS structures in the genesis of symptoms observed in cognitive and behavioural domains.


Assuntos
Síndrome de Asperger , Transtorno do Espectro Autista , Humanos , Masculino , Adolescente , Transtorno do Espectro Autista/diagnóstico por imagem , Síndrome de Asperger/diagnóstico por imagem , Síndrome de Asperger/psicologia , Giro do Cíngulo , Lobo Frontal , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem
14.
Psychiatr Pol ; 56(5): 1079-1092, 2022 Oct 31.
Artigo em Inglês, Polonês | MEDLINE | ID: mdl-37074858

RESUMO

OBJECTIVES: Goal: to assess fMRI activation during semantic tasks in adolescents with ASD. METHODS: Material: 44 right-handed male adolescents aged 12-19 (mean 14.3 ± 2.0) - 31 with autism spectrum disorders who met DSM-IV-TR criteria for Asperger's syndrome and 13 neurotypical adolescents matched according to age and handiness. Method: Functional testing (fMRI) was performed during semantic decisions tasks and phonological decisions in three categories of tasks: concrete nouns, verbs with plural meanings, words describing states of mind, as a control condition. Statistical analyzes were performed at the level of p <0.05 with FWE (family-wise error) correction and p <0.001. RESULTS: Results: lower BOLD signal was demonstrated in many brain areas including precuneus, posterior cingulate gyrus, angular gyrus, parahippocampal gyrus, regardless of task category and processing method in the ASD group. The smallest differences in semantic processing were found for concrete nouns and the greatest ones for words describing states of mind. CONCLUSIONS: Conclusions: the presence of different activation patterns in the ASD group suggests that far more than just the areas traditionally attributed to language processing, are involved in semantic deficits in ASD.


Assuntos
Síndrome de Asperger , Transtorno do Espectro Autista , Humanos , Masculino , Adolescente , Semântica , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Síndrome de Asperger/diagnóstico por imagem , Mapeamento Encefálico/métodos
15.
Cortex ; 133: 247-265, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33157345

RESUMO

The temporoparietal junction (TPJ) and related areas are activated when a target stimulus appears at unexpected locations in Posner's spatial-cueing paradigm, and also when deviant stimuli are presented within a series of standard events in oddball paradigms. This type of activation corresponds to the ventral attention network (VAN), for regions defined on the basis of the spatial task. However, involvement of the VAN in object-based updating of attention has rarely been examined. In the present study, we used functional magnetic resonance imaging to investigate brain responses to (i) invalid targets after category-cueing and (ii) neutrally cued targets deviating in category from the background series of pictures. Bilateral TPJ activation was observed in response to invalidly cued targets, as compared to neutrally cued targets. Reference to the main large-scale brain networks showed that peaks of this activation located in the angular gyrus and inferior parietal lobule belonged to the default mode (DMN) and fronto-parietal networks (FPN), respectively. We found that VAN regions were involved only for simple detection activity. We conclude that spatial and non-spatial reorienting of attention rely on different network underpinnings. Our data suggest that DMN and FPN activity may support the ability to disengage from contextually irrelevant information.


Assuntos
Mapeamento Encefálico , Lobo Parietal , Encéfalo/diagnóstico por imagem , Sinais (Psicologia) , Humanos , Imageamento por Ressonância Magnética , Lobo Parietal/diagnóstico por imagem
16.
Front Hum Neurosci ; 14: 119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351372

RESUMO

The theory of mind (ToM) is the ability to attribute mental states to others and is extremely important for social functioning. It has been widely examined in both behavioral and neuroimaging research, usually with the use of the many versions of the false-belief (FB) task. However, there is still not enough evidence from studies on the neurodevelopmental mechanisms of ToM mostly because of methodological limitations: lack of selectivity, mismatch of experimental and control tasks, and focusing on participants older than 6 years old. In the current study, we attempted to develop a computerized tool for ToM assessment suitable for both behavioral and neuriomaging testing in preschoolers. We designed a version of the classic change-of-location task with custom visuals and three fine-tuned conditions: FB, true-belief, and no-belief (NB). The usability of the task for further application in neurodevelopmental research was tested with three methods: first, behaviorally, with the use of a touch screen on a group of 75 children, followed by a functional MRI (fMRI) study on 13 adults, and a functional near-infrared spectroscopy (fNIRS) study on 19 preschool children. In line with our expectations, on the behavioral level, our task elicited the all-or-none performance in preschoolers. There was also a progression of performance with age in the FB condition. On the neural level, we observed the activation of structures involved in the ToM brain network in response to our task in both adults and children. The results therefore suggest that our task can be a useful tool for studying ToM development and its neural underpinnings.

17.
Pol J Radiol ; 85: e118-e124, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322317

RESUMO

PURPOSE: The management of patients with disorders of consciousness (DOC) constitutes a challenge for clinicians. CASE REPORT: We present the case of a 66-year-old man who developed coma with subsequent DOC after a severe traumatic brain injury. Behavioural assessment constitutes the gold standard in the evaluation of patients with DOC. In the case presented herein the neuropsychological findings were ambiguous, and the patient underwent functional magnetic resonance imaging (fMRI) to determine whether he was in a vegetative state or minimally conscious state. Three paradigms: passive, active, and resting state fMRI were used to study the brain activity in our patient. CONCLUSIONS: fMRI provided reliable evidence of preserved minimal consciousness. The neuroimaging techniques used in our patient were vital for his further treatment.

18.
Front Hum Neurosci ; 14: 589802, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424565

RESUMO

Aphasia is an acquired impairment of language functions resulting from a brain lesion. It is usually accompanied by deficits in non-linguistic cognitive processes. This study aimed to investigate in patients with aphasia the complex interrelationships between selected cognitive functions: auditory speech comprehension, working memory (WM), and temporal information processing (TIP) in the millisecond time range. Thirty right-handed subjects (20 males) aged from 27 to 82 years suffering from post-stroke aphasia participated in the study. Verbal working memory (VWM) and spatial working memory (SWM) were assessed with: (1) a receptive verbal test and (2) the Corsi Block-Tapping Test, respectively. Both these WM tests used the forward tasks (mainly engaging maintenance processes, i.e., storing, monitoring, and matching information) and backward tasks (engaging both maintenance and manipulation processes, i.e., reordering and updating information). Auditory comprehension was assessed by receptive language tests, and TIP efficiency was assessed by auditory perception of temporal order in the millisecond time range. We observed better performance of forward WM tasks than backward ones, independently of the type of material used. Furthermore, the severity of auditory comprehension impairment correlated with the efficiency on both forward and backward VWM tasks and the backward SWM task. Further analysis revealed that TIP plays a crucial role only in the latter task. These results indicate the divergent pattern of interactions between WM and TIP depending on the type of WM tasks. Level of verbal competency appeared to play an important role in both VWM tasks, whereas TIP (which is associated with manipulation processes) appeared to be important for SWM, but only on the backward task.

19.
Front Hum Neurosci ; 13: 284, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507391

RESUMO

BACKGROUND: Sensory deprivation, such as hearing loss, has been demonstrated to change the intrinsic functional connectivity (FC) of the brain, as measured with resting-state functional magnetic resonance imaging (rs-fMRI). Patients with sloping sensorineural hearing loss (SNHL) are a unique population among the hearing impaired, as they have all been exposed to some auditory input throughout their lifespan and all use spoken language. MATERIALS AND METHODS: Twenty patients with SNHL and 21 control subjects participated in a rs-fMRI study. Whole-brain seed-driven FC maps were obtained, with audiological scores of patients, including hearing loss severity and speech performance, used as covariates. RESULTS: Most profound differences in FC were found between patients with prelingual (before language development, PRE) vs. postlingual onset (after language development, POST) of SNHL. An early onset was related to enhancement in long-range network connections, including the default-mode network, the dorsal-attention network and the fronto-parietal network, as well as in local sensory networks, the visual and the sensorimotor. A number of multisensory brain regions in frontal and parietal cortices, as well as the cerebellum, were also more internally connected. We interpret these effects as top-down mechanisms serving optimization of multisensory experience in SNHL with a prelingual onset. At the same time, POST patients showed enhanced FC between the salience network and multisensory parietal areas, as well as with the hippocampus, when they were compared to those with PRE hearing loss. Signal in several cortex regions subserving visual processing was also more intra-correlated in POST vs. PRE patients. This outcome might point to more attention resources directed to multisensory as well as memory experience. Finally, audiological scores correlated with FC in several sensory and high-order brain regions in all patients. CONCLUSION: The results show that a sloping hearing loss is related to altered resting-state brain organization. Effects were shown in attention and cognitive control networks, as well as visual and sensorimotor regions. Specifically, we found that even in a partial hearing deficit (affecting only some of the hearing frequency ranges), the age at the onset affects the brain function differently, pointing to the role of sensitive periods in brain development.

20.
Neurol Neurochir Pol ; 53(4): 304-310, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31441496

RESUMO

DESIGN: Migraine is regarded as a complex brain dysfunction of sensory and modulatory networks with the secondary sensitisation of the trigeminal system as well as the affected brain area's activities. The particular role of the hippocampus and the brainstem in the first phase of the attack, the disrupted cognitive network, and the activation of the limbic and visual systems, are the main discoveries in the field of migraine imaging that have been achieved using functional techniques. Thus advanced neuroimaging has been widely employed to study the pathogenesis of migraine. OBJECTIVE: The evaluation of fMRI BOLD images of migraine patients with or without aura, with particular attention to the interictal phase. SUBJECTS AND METHODS: The aim of this study was to compare brain activity during visual stimuli by fMRI BOLD in the interictal phase (black and white checkerboard tests, static or flickering) of 16 migraine patients, eight with aura and eight without. RESULTS: We demonstrated differences in the right part of the brainstem, the left part of the cerebellum, and in the right middle temporal gyrus. However, the bilateral brain activation in the occipital and frontal lobe remained similar. CONCLUSIONS: Results of our preliminary study suggest that migraine with aura and migraine without aura might be separate disorders, and this requires further investigation.


Assuntos
Epilepsia , Enxaqueca com Aura , Enxaqueca sem Aura , Encéfalo , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Enxaqueca com Aura/diagnóstico por imagem , Enxaqueca sem Aura/diagnóstico por imagem
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