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1.
J Neurosci Res ; 99(10): 2377-2389, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34185890

RESUMO

Social interactions are partly driven by our ability to empathize-the capacity to share and understand others' inner states. While a growing body of evidence suggests a link between past experiences and empathy, to what degree empathy is dependent on our own previous experiences (autobiographical memories, AMs) is still unclear. Whereas neuroimaging studies have shown wide overlapping brain networks underpinning AM and empathic processes, studies on clinical populations with memory loss have not always shown empathy is impaired. The current transcranial magnetic stimulation (TMS) and electroencephalography study will seek to shed light on this neuropsychological puzzle by testing whether self-perceived empathy is causally linked to AM retrieval. Cortical activity, together with self-rating of empathy, will be recorded for scenarios that echo personal experiences while a brain region critical for AM retrieval will be transiently inhibited using TMS before task performance.


Assuntos
Conscientização/fisiologia , Eletroencefalografia/métodos , Empatia/fisiologia , Memória Episódica , Desempenho Psicomotor/fisiologia , Estimulação Magnética Transcraniana/métodos , Adolescente , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Projetos Piloto , Adulto Jovem
2.
Hum Brain Mapp ; 41(14): 3938-3955, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32573907

RESUMO

Previous studies have shown age-related impairments in the ability to suppress salient distractors. One possibility is that this is mediated by age-related impairments in the recruitment of the left intraparietal sulcus (Left IPS), which has been shown to mediate the suppression of salient distractors in healthy, young participants. Alternatively, this effect may be due to a shift in engagement from proactive control to reactive control, possibly to compensate for age-related impairments in proactive control. Another possibility is that this is due to changes in the functional specificity of brain regions that mediate salience suppression, expressed in changes in spontaneous connectivity of these regions. We assessed these possibilities by having participants engage in a proactive distractor suppression task while in an fMRI scanner. Although we did not find any age-related differences in behavior, the young (N = 15) and older (N = 15) cohorts engaged qualitatively distinctive brain networks to complete the task. Younger participants engaged the predicted proactive control network, including the Left IPS. On the other hand, older participants simultaneously engaged both a proactive and a reactive network, but this was not a consequence of reduced network specificity as resting state functional connectivity was largely comparable in both age groups. Furthermore, improved behavioral performance for older adults was associated with increased resting state functional connectivity between these two networks. Overall, the results of this study suggest that age-related differences in the recruitment of a left lateralized ventral fronto-parietal network likely reflect the specific recruitment of reactive control mechanisms for distractor inhibition.


Assuntos
Envelhecimento/fisiologia , Atenção/fisiologia , Conectoma , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Córtex Pré-Frontal/fisiologia , Percepção Espacial/fisiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Lobo Parietal/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
3.
Cereb Cortex ; 25(4): 1060-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24165832

RESUMO

Perceptual learning is associated with experience-based changes in stimulus salience. Here, we use a novel procedure to show that learning a new association between a self-label and a neutral stimulus produces fast alterations in social salience measured by interference when targets associated with other people have to be selected in the presence of self-associated distractors. Participants associated neutral shapes with either themselves or a friend, over a short run of training trials. Subsequently, the shapes had to be identified in hierarchical (global-local) forms. The data show that giving a shape greater personal significance by associating it with the self had effects on visual selection equivalent to altering perceptual salience. Similar to previously observed effects linked to when perceptually salient distractors are ignored, effects of a self-associated distractor also increased activation in the left intraparietal cortex sulcus. The results show that self-associations to sensory stimuli rapidly modulate neural responses in a manner similar to changes in perceptual saliency. The self-association procedure provides a new way to understand how personal significance affects behavior.


Assuntos
Aprendizagem/fisiologia , Lobo Parietal/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Autoimagem , Adulto Jovem
4.
J Vis ; 16(11): 27, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27690167

RESUMO

The ability to inhibit distracting information-distractor suppression-is a fundamental process for the visual and motor systems. Whereas aging is typically linked to a general decline in cognitive processing, a specific impairment in distractor suppression is found during visual attention tasks. Despite this, the effect of aging on a human's capacity to inhibit distracting information during a motor task is currently unknown. Therefore, we tested the ability of young and older adults to inhibit distracting information during a visual attention (global-local) and a motor (reaching) task. When faced with distractors, younger and older adults displayed significant behavioral impairments (accuracy and speed) across both tasks. However, these deficits were substantially enhanced in older adults. Intriguingly, the amount of distractor impairment observed within each participant was correlated across the visual and motor tasks, irrespective of age group. Thus, while all participants' ability to inhibit distractors was correlated across the visual and motor domain, older adults displayed a generalized distractor inhibition deficit. We propose that a shift from proactive to reactive control in older adults could explain such impairment. These results may have important implications regarding the ability of older adults to effectively deal with distractors during complex visuomotor tasks such as driving.

5.
Autism Res ; 17(4): 702-715, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38456581

RESUMO

Autistic individuals can experience difficulties with attention reorienting and Theory of Mind (ToM), which are closely associated with anterior and posterior subdivisions of the right temporoparietal junction. While the link between these processes remains unclear, it is likely subserved by a dynamic crosstalk between these two subdivisions. We, therefore, examined the dynamic functional connectivity (dFC) between the anterior and posterior temporoparietal junction, as a biological marker of attention and ToM, to test its contribution to the manifestation of autistic trait expression in Autism Spectrum Condition (ASC). Two studies were conducted, exploratory (14 ASC, 15 TD) and replication (29 ASC, 29 TD), using resting-state fMRI data and the Social Responsiveness Scale (SRS) from the Autism Brain Imaging Data Exchange repository. Dynamic Independent Component Analysis was performed in both datasets using the CONN toolbox. An additional sliding-window analysis was performed in the replication study to explore different connectivity states (from highly negatively to highly positively correlated). Dynamic FC was reduced in ASC compared to TD adults in both the exploratory and replication datasets and was associated with increased SRS scores (especially in ASC). Regression analyses revealed that decreased SRS autistic expression was predicted by engagement of highly negatively correlated states, while engagement of highly positively correlated states predicted increased expression. These findings provided consistent evidence that the difficulties observed in ASC are associated with altered patterns of dFC between brain regions subserving attention reorienting and ToM processes and may serve as a biomarker of autistic trait expression.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Adulto , Humanos , Masculino , Transtorno Autístico/diagnóstico por imagem , Mapeamento Encefálico , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
6.
Sci Rep ; 14(1): 984, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200101

RESUMO

This study focuses on the cross-cultural adaptation of the Emotional Outburst Questionnaire (EOQ) to Brazilian Portuguese and preliminarily assesses its predictive validity. The EOQ evaluates aspects of emotional outbursts (EO), including frequency, duration, intensity, types, associated behaviours, recovery time, triggers, and effectiveness of calming strategies. Two independent translators performed the translation, with subsequent synthesis and analysis revealing that only 33 items (24.81%) required revision. Among these, one item needed partial modification, and two needed total modification. The study demonstrated strong content validity and adaptation in terms of conceptual, idiomatic, and semantic aspects. The EOQ's predictive validity was assessed by analysing the interruption of mental health services in Brazil due to Covid-19 (T1) compared to when services resumed after social distancing measures were lifted (T2). Parents of 25 individuals with developmental disabilities (ASD, DS and ID), with a mean of 11 y/o, mostly male (76%), completed the EOQ. Service interruption during T1 led to increased frequency and duration of severe emotional outbursts reported by caregivers compared to T2 (frequency: p < .001; duration: p = 0.05). This suggests that the EOQ exhibits predictive validity and sensitivity to changes influenced by individual contexts. These findings highlight the EOQ's potential as an outcome measure for intervention development.


Assuntos
Emoções , Transtornos do Humor , Humanos , Masculino , Feminino , Brasil , Psicometria , Pessoal Técnico de Saúde
7.
J Autism Dev Disord ; 53(11): 4229-4242, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35984587

RESUMO

The causal relationship between emotional outbursts and emotion dysregulation is proposed to be heterogeneous, but cultural influences have not been considered despite established cultural differences in emotional processes (e.g., increased motivation to suppress emotions in interdependent cultures). Responses to the Brazilian Portuguese version of the Emotional Outburst Questionnaire were collected from 327 caregivers of young people (6-25 years) with autism spectrum disorder, Down's syndrome, or intellectual disability. Responses were compared to a previous sample of 268 responses from the English version of the questionnaire. The latent factor structure of the contextual items was measurement invariant across both versions. The Brazilian responses were classified into three distinct clusters (Sensory Sensitivity; Perceived Safety; Perceived Unsafety) which considerably overlapped with the English clusters.


Assuntos
Transtorno do Espectro Autista , Comparação Transcultural , Humanos , Adolescente , Emoções , Inquéritos e Questionários , Transtornos do Humor , Brasil
8.
Hum Brain Mapp ; 33(1): 105-20, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21425391

RESUMO

Recent research indicates that working memory (WM) and attention interact, with attention automatically biased to stimuli that match the contents of WM. Though there is behavioral evidence for verbal guidance (written words) as well as guidance by more visual cues in WM, we have limited understanding of how these two representational formats influence the guidance of visual selection at a neural level. Here, we present converging evidence from functional MRI and transcranial magnetic stimulation (TMS), which indicates that both common and distinct neural regions mediate the influence of visuoverbal representations on WM. Colored shapes, but not words, in WM activated the superior frontal gyrus (SFG) and recognition memory areas in the temporal lobe when the contents of WM matched a stimulus in a subsequent search display. rTMS to the SFG disrupted WM effects from colored shapes. The lateral occipital cortex, however, tended to be more activated with written word cues, and rTMS to the lateral occipital complex tended to disrupt effects from written words more than from colored shapes in WM. There was also evidence for cue validity effects from colored shapes and written stimuli operating through different subthalamic nuclei. We discuss the evidence for understanding the neural systems mediating attention effects from WM.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Memória de Curto Prazo/fisiologia , Visão Ocular/fisiologia , Adulto , Sinais (Psicologia) , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estimulação Luminosa , Estimulação Magnética Transcraniana
9.
Sci Rep ; 12(1): 7414, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523842

RESUMO

Emotional outbursts or temper outbursts are challenging behaviours commonly experienced by people with neurodevelopmental disorders and people who have experienced childhood adversity, which can negatively impact individuals and their families. Emotional outbursts may manifest in different situations via unique pathways distinguished by context-specific differences in the regulation and expression of emotions. Caregivers (N = 268) of young people (6-25 years) with emotional outbursts completed a bespoke caregiver-report questionnaire. Potential pathways were identified by examining the patterns of antecedents and setting events related to outbursts through factor and cluster analyses. Six contextual factors were derived from the Emotional Outburst Questionnaire. Based on these factors, the responses were classified into three clusters, which may represent potential pathways of emotional outbursts. The three clusters were characterized by the increased likelihood of outbursts: (1) across all setting events and triggers; (2) in safe setting events; (3) in unsafe setting events. These potential pathways may be related to: (1) differences in sensory processing; (2) masking of emotions in unsafe environments; (3) differences in safety perception. This framework supports a transdiagnostic account of emotional outbursts and may facilitate the development of pathway-specific intervention strategies.


Assuntos
Emoções , Transtornos do Humor , Adolescente , Cuidadores/psicologia , Humanos , Inquéritos e Questionários
10.
Brain Imaging Behav ; 16(3): 1003-1013, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34705186

RESUMO

It is widely assumed that cognitive processes studied in fMRI are equivalent to cognitive processes engaged in the same experimental paradigms in typical behavioral lab settings. Yet very few studies examined this common assumption, and the results have been equivocal. In the current study we directly tested the effects of fMRI environment on sustained attention and response inhibition, using a Go/No-go task, among participants with (n = 42) and without (n = 21) attention deficit/hyperactivity disorder (ADHD). Participants with ADHD are characterized by deficits in these cognitive functions and may be particularly susceptible to environmental effects on attention. We found a substantial slowing of reaction time in the scanner for all participants, and a trend for enhanced sustained attention, particularly in ADHD participants with poor performance. We also report limited stability of individual differences in scores obtained in the lab and in the scanner. These findings call for cautious interpretation of neuroimaging task-related results, especially those obtained in clinical populations.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Cognição , Humanos , Individualidade , Imageamento por Ressonância Magnética , Tempo de Reação/fisiologia
11.
J Neurosci ; 30(17): 6072-9, 2010 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-20427665

RESUMO

How do we ignore stimuli that are salient but irrelevant when our task is to select a lower salient stimulus? Since bottom-up processes favor high saliency, detection of a low-salient target in the presence of highly salient distractors requires top-down attentional guidance. Previous studies have demonstrated that top-down attention can modulate perceptual processing and also that the control of attention is driven by frontoparietal regions. However, to date, there is no direct evidence on the cause and effect relationship between control regions and perceptual processing. Here, we report the first evidence demonstrating a neural circuit for the downregulation of salient distractors when a low-salient target is selected, combining brain imaging using functional magnetic resonance imaging with brain stimulation by transcranial magnetic stimulation. Using these combined techniques, we were able to identify a cause and effect relationship in the suppression of saliency, based on an interaction between the left intraparietal sulcus (IPS) and a region implicated in visual processing in our task (the left occipital pole). In particular, low-salient stimuli were selected by the left IPS suppressing early visual areas that would otherwise respond to a high-saliency distractor in the task. Apart from providing a first documentation of the neural circuit supporting selection by saliency, these data can be critical for understanding the underlying causes of problems in ignoring irrelevant salience that are found in both acquired and neurodevelopmental disorders (e.g., attention deficit/hyperactivity disorder or autism).


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Função Executiva/fisiologia , Percepção Visual/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Testes Neuropsicológicos , Lobo Parietal/fisiologia , Estimulação Magnética Transcraniana
12.
J Autism Dev Disord ; 51(2): 666-676, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32601925

RESUMO

The role of relative salience in processing of hierarchical stimuli in individuals with autism spectrum disorder (ASD) was examined in this study. Participants with ASD and typically developing controls performed a Navon letters task under conditions of global salience, local salience or equal salience of both levels. Results revealed no group differences in level of processing (global or local) and no local bias for ASD. Rather, both groups showed better performance when targets were more salient compared to when distractors were more salient. Importantly, participants with ASD exhibited increased sensitivity to salience at the distractor level. We conclude that inconsistent findings in the context of global/local processing in ASD may stem from such exaggerated salience effects.


Assuntos
Atenção/fisiologia , Transtorno do Espectro Autista/psicologia , Estimulação Luminosa/métodos , Desempenho Psicomotor/fisiologia , Adolescente , Transtorno do Espectro Autista/diagnóstico , Feminino , Humanos , Masculino , Adulto Jovem
13.
Res Dev Disabil ; 116: 104041, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34303277

RESUMO

BACKGROUND: Autism Spectrum Disorder (ASD) is characterized by impairments in social interaction, restricted and repetitive behaviour, interests or activities. Difficulties in a broad spectrum of cognitive skills is often present, including attentional processes and nonverbal intelligence, which might be related to academic difficulties. AIMS: In this study, the association between attentional skills and nonverbal intelligence to school performance of children with ASD was assessed. METHODS AND PROCEDURES: 32 children/adolescents between 8-14 years old, who attended a treatment unit linked to the public health system of São Paulo-Brazil participated in the study. The following instruments were utilized: Cancellation Attention Test; Raven's Coloured Progressive Matrices; and School Performance Test. OUTCOMES AND RESULTS: After correlation analysis, statistically significant associations were found between attention and nonverbal intelligence with school performance. Regression analysis showed that attention drives school performance irrespective of nonverbal intelligence. CONCLUSIONS AND IMPLICATIONS: Results evidence the link between attention and school performance in ASD, suggesting that attentional mechanisms may be a promising route to follow in the design of interventions for school improvement of children and adolescents with ASD.


Assuntos
Transtorno do Espectro Autista , Adolescente , Atenção , Brasil , Criança , Humanos , Inteligência , Saúde Pública , Instituições Acadêmicas
14.
Autism Res ; 14(8): 1769-1776, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34227246

RESUMO

Atypical attention has been reported in individuals with autism spectrum disorder (ASD) with studies pointing to an increase in attention deficit and hyperactivity disorder-like symptomatology. Individuals with ASD may also present academic difficulties and it is possible that they face a double-barrier for academic attainment from both core ASD symptomatology and from attention atypicalities, which are directly linked to academic performance. This raises the possibility that academic difficulties in ASD may benefit from cognitive training targeting attention. To test this possibility, we used the computerized progressive attentional training (CPAT) intervention in a double-blind, active control with follow-up intervention study in Brazil. The CPAT is a computerized attention training program that was recently piloted with schoolchildren with ASD in the UK. Twenty-six participants (8-14 years) with ASD in the São Paulo's ASD Reference Unit were assigned to either the CPAT (n = 14) or active control group (n = 12), which were matched at baseline. Two 45-min intervention sessions per week were conducted over a 2-month period. School performance, attention, fluid intelligence, and behavior were assessed before, immediately after and 3 months following the intervention. Significant group by time interactions show improvements in math, reading, writing and attention that were maintained at follow-up for the CPAT (but not the active control) group, while parents of children from both groups tended to report behavioral improvements. We conclude that attention training has the potential to reduce obstacles for academic attainment in ASD. Combined with the previous pilot study, the current results point to the generality of the approach, which leads to similar outcomes in different cultural and social contexts. LAY ABSTRACT: Attention difficulties tend to occur in ASD and are linked to academic performance. In this study, we demonstrate that school performance in math, reading and writing in children with ASD can improve following an intervention that trains basic attention skills (the CPAT intervention). The improvements we report are stable and were maintained 3-months following the intervention. This study, which was conducted in a public-health setting in Brazil, extends previous research in schools in the UK pointing to the cross-cultural and cross-settings efficacy of the intervention.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/terapia , Brasil , Criança , Humanos , Projetos Piloto , Leitura
15.
Cereb Cortex ; 19(1): 106-14, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18515299

RESUMO

In visual search, the presence of a highly salient color singleton can slow or facilitate search for a shape target depending on whether the singleton is a distractor or coincides with the target. This is consistent with an attentional shift (attentional capture) to the salient item. This attentional capture can be driven by bottom-up or top-down processes or both. We investigated the role of the parietal cortex in attentional capture by a singleton using repetitive transcranial magnetic stimulation. Following disruption to the right posterior parietal cortex by sustained transcranial magnetic stimulation, the reaction time (RT) cost of the singleton distractor was reduced. At least part of this lessening of singleton distraction was due to the elimination of priming (top-down) effects between target and distractor singletons on consecutive trials. In Experiment 2, we presented the different conditions in separate blocks meaning any effects of the distractor can most likely be attributed to bottom-up processes. Nevertheless, there was still a decrease in RT interference from the distractor so that a reduction in priming cannot provide a full account of the results. The data are consistent with previous work positing that the right parietal cortex directs attention to salient stimuli (e.g., Constantinidis 2005, Mevorach et al. 2006), while also suggesting a role for the right parietal cortex in the integration of bottom-up salience information with memories for salient features on prior trials.


Assuntos
Atenção/fisiologia , Sinais (Psicologia) , Rememoração Mental/fisiologia , Lobo Parietal/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Mascaramento Perceptivo/fisiologia , Análise e Desempenho de Tarefas , Estimulação Magnética Transcraniana/métodos , Adulto , Feminino , Humanos , Masculino
16.
Nat Neurosci ; 9(6): 740-2, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16699505

RESUMO

Visual selection is determined in part by the saliency of stimuli. We assessed the brain mechanisms determining attentional responses to saliency. Repetitive transcranial magnetic stimulation (rTMS) was applied to the left and right posterior parietal cortices (PPC) immediately before participants were asked to identify a compound letter. rTMS to the right PPC disrupted the guidance of attention toward salient stimuli, whereas rTMS to the left PPC affected the ability to bias selection away from salient stimuli. We conclude that right and left PPC have opposite roles in biasing selection to and from salient stimuli in the environment.


Assuntos
Atenção/fisiologia , Lateralidade Funcional/fisiologia , Lobo Parietal/anatomia & histologia , Lobo Parietal/fisiologia , Percepção Visual/fisiologia , Humanos , Rede Nervosa/anatomia & histologia , Rede Nervosa/fisiologia , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Testes Neuropsicológicos , Variações Dependentes do Observador , Orientação/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Percepção Espacial/fisiologia , Estimulação Magnética Transcraniana
17.
Psychon Bull Rev ; 27(1): 191, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31676978

RESUMO

This article was originally published with errors in the graphs. It has been republished with corrections.

18.
Neuroimage Clin ; 25: 102119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31865022

RESUMO

BACKGROUND: Impaired response inhibition is one of the most consistent findings in attention deficit hyperactivity disorder (ADHD). However, the underlying brain mechanisms are not clear. This study aimed to underpin atypical inhibition-related brain activation and connectivity patterns in ADHD using a novel Go/No-go task design, and to determine its association with clinical symptoms of the disorder. METHODS: Forty-eight adults with ADHD performed a Go/No-go task in which target frequency was manipulated during functional MRI. Specific inhibition-related brain activation was correlated with ADHD symptom severity, to assess the relationship of individual differences in engagement of inhibition-related brain circuits with the magnitude of every-day functioning impairments. Finally, generalized psychophysical interaction analyses were carried out to examine whether not only engagement but also functional connectivity between regions implicated in response inhibition is related to symptom severity. RESULTS: We found no evidence for the expected parietal modulation by increased demand for inhibition at the group-level results. However, this lack of modulation was mediated by individual differences in ADHD symptom severity - increased engagement of the intraparietal sulcus (IPS) in inhibition-demanding events was evident in individuals with less severe symptoms but dissipated with increase in symptomatology. Similarly, functional connectivity between the IPS and the right inferior frontal gyrus (rIFG) was elevated under high inhibitory demand conditions, but this effect diminished with increased symptom severity. CONCLUSIONS: The results highlight the importance of IPS engagement in response inhibition and suggest that IPS modulation may be driven by top-down control from the IFG. Moreover, the current findings force the point of treating ADHD as a continuum whereby brain correlates are scaled with severity of the disorder, and point to the potential use of individual differences in the modulation of IPS activation and connectivity as a neuromarker of ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Encéfalo/fisiopatologia , Vias Neurais/fisiopatologia , Tempo de Reação/fisiologia , Adulto , Feminino , Humanos , Inibição Psicológica , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
19.
Nat Neurosci ; 8(3): 276-7, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15696162

RESUMO

Our perceptions of the whole and of the parts of a visual stimulus are mediated by different brain regions. We used low-frequency transcranial magnetic stimulation (TMS) to show for the first time that opposite, homologous regions in the two hemispheres are involved in attending to local parts for left- and right-handed individuals. The brain regions that focus on the 'trees' while ignoring the 'forest' are switched as a function of handedness.


Assuntos
Atenção , Encéfalo/fisiologia , Dominância Cerebral/fisiologia , Estimulação Elétrica/métodos , Magnetismo , Campos Visuais/fisiologia , Análise de Variância , Encéfalo/anatomia & histologia , Encéfalo/efeitos da radiação , Mapeamento Encefálico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Tempo de Reação/efeitos da radiação
20.
Psychon Bull Rev ; 26(6): 1870-1888, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31183745

RESUMO

The cognitive aging literature suggests that aging populations exhibit impairments in the proactive inhibition of attention. Although proactive inhibition is often preceded by the allocation of attention toward the predicted or known spatial location of to-be-ignored stimuli, proactive allocation of attention has not been assessed in aging populations. In this study, an older and younger cohort engaged in the attentional-white-bear paradigm which measures proactive allocation of attention. In this task, on 80% of trials, participants must identify a centrally located letter surrounded by congruent or incongruent flanker letters. The flanker locations are fixed and predictable within each block of the study. On 20% of trials, they must identify which of two dots appear first on the screen. One dot appears in the same location as the flanker, and one appears in an empty location during the flanker task. The typical white-bear effect is that, despite the dots appearing at the same time, participants more often report the dot in the location of the flanker (i.e., the potentially to-be-ignored location) to appear first. The magnitude of this effect is interpreted as the magnitude of attentional allocation prior to inhibition. In Experiment 1, there was no difference in the magnitude of the attentional white bear between younger and aging cohorts. However, when the attentional system was sufficiently taxed by reducing the flanker presentation (Experiments 2a and 2b), age-related differences emerged. In particular, older participants showed a reduced white-bear effect, reflecting a potential impairment in the proactive allocation of attention toward the location of expected distractors.


Assuntos
Envelhecimento/fisiologia , Atenção/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Inibição Proativa , Percepção Espacial/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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