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1.
Arch Phys Med Rehabil ; 104(7): 1026-1034, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37142177

RESUMO

OBJECTIVE: To determine program satisfaction and preliminary efficacy of Traumatic Brain Injury Positive Strategies (TIPS), a web-based training for parenting strategies after child brain injury. DESIGN: A randomized controlled trial with parallel assignment to TIPS intervention or usual-care control (TAU). The three testing time-points were pretest, posttest within 30 days of assignment, and 3-month follow-up. Reported in accordance with CONSORT extensions to randomized feasibility and pilot trials SETTING: Online. PARTICIPANTS: Eighty-three volunteers recruited nationally who were 18 years of age or older, U.S. residents, English speaking and reading, had access to high-speed internet, and were living with and caring for a child who was hospitalized overnight with a brain injury (ages 3-18 years, able to follow simple commands; N=83). INTERVENTIONS: Eight interactive behavioral training modules on parent strategies. The usual-care control was an informational website. MAIN OUTCOME MEASURES: The proximal outcomes were User Satisfaction, Usefulness, Usability, Feature Preference, Strategy Utilization and Effectiveness, and Learning and Self-Efficacy for TIPS program participants. The primary outcomes were: Strategy Knowledge, Application, and Strategy-Application Confidence; Family Impact Module of Pediatric Quality of Life Inventory (PedsQL); and Caregiver Self-Efficacy Scale. The secondary outcomes were TIPS vs TCore PedsQL and Health Behavior Inventory (HBI) RESULTS: Pre- and posttest assessments were completed by 76 of 83 caregivers; 74 completed their 3-month follow-up. Linear growth models indicated that relative to TAU, TIPS yielded greater increases in Strategy Knowledge over the 3-month study (d=.61). Other comparisons did not reach significance. Outcomes were not moderated by child age, SES, or disability severity measured by Cognitive Function Module of PedsQL. All TIPS participants were satisfied with the program. CONCLUSIONS: Of the 10 outcomes tested, only TBI knowledge significantly improved relative to TAU.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Criança , Humanos , Adolescente , Adulto , Qualidade de Vida , Projetos Piloto , Lesões Encefálicas/complicações , Pais , Lesões Encefálicas Traumáticas/psicologia
2.
J Exp Child Psychol ; 227: 105584, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36413871

RESUMO

In children, the ability to attend to relevant auditory information and ignore distracting information is crucial for learning and educational achievement. Distractibility, the propensity to pay attention to irrelevant information, depends on multiple components of cognition (voluntary attention orienting, sustained attention, distraction resulting from the capture of attention by a distractor, phasic arousal, impulsivity, and motor control) that may mature at different ages. Here, we used the Competitive Attention Test (CAT) to measure these components in children aged 3 to 5 years. Our goal was to characterize changes in the efficiency of attention during the preschool period and to determine whether distractibility varies as a function of socioeconomic status (SES). All 3-year-olds (n = 14) and some 4- and 5-year-olds (n = 21) needed to be excluded from the sample due to noncompliance with instructions, suggesting that the CAT might not be suitable for children with poorly developed skills in sustained attention. Among 4- and 5-year-olds who completed the CAT (n = 71), sustained attention improved with age, whereas voluntary attention orienting remained immature. Independent of age, task-irrelevant sounds induced distraction, phasic arousal, and impulsivity. There was no relationship between SES and children's distraction. Finally, children from lower SES backgrounds showed reduced sustained attention abilities and increased impulsivity. Taken together, these findings suggest that distractibility is still developing during the preschool period and is likely to vary depending on the SES background of a child's family.


Assuntos
Classe Social , Som , Pré-Escolar , Humanos , Estimulação Acústica/métodos , Aprendizagem , Cognição
3.
Intellect Dev Disabil ; 60(4): 303-315, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35868300

RESUMO

Supportive, informed parenting is critical to improve outcomes of children who experience intellectual and developmental disabilities (IDD). Parents want to learn about their child's condition, needs, and strategies to improve family life. The internet is a valuable resource, but how parents evaluate and apply information is unknown. We conducted focus groups to understand how parents use internet resources to learn about their children with IDD. Parents described using the internet to access information from trusted sources, find examples to apply their knowledge, and seek social support. Social learning theory, which posits that cognitive, behavioral, and social processes influence each other to support real-world learning, could provide a theoretical framework for unifying these findings and for designing efficacious online interventions.


Assuntos
Deficiência Intelectual , Aprendizado Social , Criança , Deficiências do Desenvolvimento , Humanos , Poder Familiar , Pais/psicologia
4.
Dev Psychol ; 54(9): 1674-1686, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30148395

RESUMO

Multiple theoretical frameworks posit that interactions between the autonomic nervous system and higher-order neural networks are crucial for cognitive regulation. However, few studies have simultaneously examined autonomic physiology and brain activity during cognitive tasks. Such research is promising for understanding how early adversity impacts neurocognitive development in children, given that stress experienced early in life impacts both autonomic function and regulatory behaviors. We recorded event-related potentials (ERPs) as a neural measure of auditory selective attention, and cardiovascular measures of high-frequency heart rate variability (HF-HRV) and preejection period (PEP), in 105 3-5-year-old children with varying degrees of socioeconomic risk. First, we replicated a previous study from our lab: Increased socioeconomic risk was associated with larger ERP amplitudes elicited by distracting sounds. Next, we tested whether PEP and HF-HRV (at rest and during the task) were associated with the distractor ERP response, and found that a physiological profile marked by heightened sympathetic nervous system activity, indexed by shorter PEP, was associated with better ERP suppression of distractor sounds in lower SES children. Finally, we found that PEP mediated the relationship between socioeconomic risk and larger ERP responses to distractor sounds. In line with similar reports, these results suggest that for lower SES children, there is a potential biological cost of achieving better cognitive performance, seen here as increased cardiovascular arousal both at rest and in response to task demands. (PsycINFO Database Record


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Potenciais Evocados , Frequência Cardíaca , Pobreza/psicologia , Sistema Nervoso Simpático/fisiologia , Pré-Escolar , Estudos Transversais , Eletrocardiografia , Eletroencefalografia , Feminino , Humanos , Masculino , Risco
5.
Psychophysiology ; 55(8): e13079, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29624675

RESUMO

Multiple theoretical frameworks posit that interactions between the autonomic nervous system and higher-order neural networks are crucial for cognitive and emotion regulation. However, few studies have directly examined the relationship between measures of autonomic physiology and brain activity during cognitive tasks, and fewer studies have examined both the parasympathetic and sympathetic autonomic branches when doing so. Here, 93 adults completed an ERP auditory selective attention task concurrently with measures of parasympathetic activity (high-frequency heart rate variability; HF-HRV) and sympathetic activity (preejection period; PEP). We focus on the well-studied N1 ERP component to test for associations with baseline values of HF-HRV and PEP. Individuals with higher resting HF-HRV and shorter resting PEP showed larger effects of selective attention on their ERPs. Follow-up regression models demonstrated that HF-HRV and PEP accounted for unique variance in selective attention effects on N1 mean amplitude. These results are consistent with the neurovisceral integration model, such that greater parasympathetic activity is a marker of increased selective attention, as well as other theoretical models that emphasize the role of heightened sympathetic activity in more efficient attention-related processing. The present findings highlight the importance of autonomic physiology in the study of individual differences in neurocognitive function and, given the foundational role of selective attention across cognitive domains, suggest that both parasympathetic and sympathetic activity may be key to understanding variability in brain function across a variety of cognitive tasks.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Individualidade , Sistema Nervoso Parassimpático/fisiologia , Sistema Nervoso Simpático/fisiologia , Adulto , Idoso , Percepção Auditiva/fisiologia , Eletroencefalografia , Potenciais Evocados Auditivos , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Taxa Respiratória
6.
Dev Cogn Neurosci ; 30: 178-190, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29554639

RESUMO

During early literacy skills development, rhyming is an important indicator of the phonological precursors required for reading. To determine if neural signatures of rhyming are apparent in early childhood, we recorded event-related potentials (ERPs) from 3- to 5-year-old, preliterate children (N = 62) in an auditory prime-target nonword rhyming paradigm (e.g., bly-gry, blane-vox). Overall, nonrhyming targets elicited a larger negativity (N450) than rhyming targets over posterior regions. In contrast, rhyming targets elicited a larger negativity than nonrhyming targets over fronto-lateral sites. The amplitude of the two rhyming effects was correlated, such that a larger posterior effect occurred with a smaller anterior effect. To determine whether these neural signatures of rhyming related to phonological awareness, we divided the children into two groups based on phonological awareness scores while controlling for age and socioeconomic status. The posterior rhyming effect was stronger and more widely distributed in the group with better phonological awareness, whereas differences between groups for the anterior effect were small and not significant. This pattern of results suggests that the rhyme processes indexed by the anterior effect are developmental precursors to those indexed by the posterior effect. Overall, these findings demonstrate early establishment of distributed neurocognitive networks for rhyme processing.


Assuntos
Potenciais Evocados/fisiologia , Fonética , Pré-Escolar , Feminino , Humanos , Masculino
7.
Front Hum Neurosci ; 11: 599, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29375336

RESUMO

Gratitude is an emotion and a trait linked to well-being and better health, and welcoming benefits to oneself is instrumentally valuable. However, theoretical and empirical work highlights that gratitude is more fully understood as an intrinsically valuable moral emotion. To understand the role of neural reward systems in the association between gratitude and altruistic motivations we tested two hypotheses: First, whether self-reported propensity toward gratitude relates to fMRI-derived indicators of "pure altruism," operationalized as the neural valuation of passive, private transfers to a charity versus to oneself. In young adult female participants, self-reported gratitude and altruism were associated with "neural pure altruism" in ventromedial prefrontal cortex (VMPFC) and nucleus accumbens. Second, whether neural pure altruism can be increased through practicing gratitude. In a double-blind study, we randomly assigned participants to either a gratitude-journal or active-neutral control journal group for 3 weeks. Relative to pre-test levels, gratitude journaling increased the neural pure altruism response in the VMPFC. We posit that as a context-dependent value-sensitive cortical region, the VMPFC supports change with gratitude practice, a change that is larger for benefits to others versus oneself.

8.
Hear Res ; 343: 72-82, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27473505

RESUMO

Considerable research documents the cross-modal reorganization of auditory cortices as a consequence of congenital deafness, with remapped functions that include visual and somatosensory processing of both linguistic and nonlinguistic information. Structural changes accompany this cross-modal neuroplasticity, but precisely which specific structural changes accompany congenital and early deafness and whether there are group differences in hemispheric asymmetries remain to be established. Here, we used diffusion tensor imaging (DTI) to examine microstructural white matter changes accompanying cross-modal reorganization in 23 deaf adults who were genetically, profoundly, and congenitally deaf, having learned sign language from infancy with 26 hearing controls who participated in our previous fMRI studies of cross-modal neuroplasticity. In contrast to prior literature using a whole-brain approach, we introduce a semiautomatic method for demarcating auditory regions in which regions of interest (ROIs) are defined on the normalized white matter skeleton for all participants, projected into each participants native space, and manually constrained to anatomical boundaries. White-matter ROIs were left and right Heschl's gyrus (HG), left and right anterior superior temporal gyrus (aSTG), left and right posterior superior temporal gyrus (pSTG), as well as one tractography-defined region in the splenium of the corpus callosum connecting homologous left and right superior temporal regions (pCC). Within these regions, we measured fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD), and white-matter volume. Congenitally deaf adults had reduced FA and volume in white matter structures underlying bilateral HG, aSTG, pSTG, and reduced FA in pCC. In HG and pCC, this reduction in FA corresponded with increased RD, but differences in aSTG and pSTG could not be localized to alterations in RD or AD. Direct statistical tests of hemispheric asymmetries in these differences indicated the most prominent effects in pSTG, where the largest differences between groups occurred in the right hemisphere. Other regions did not show significant hemispheric asymmetries in group differences. Taken together, these results indicate that atypical white matter microstructure and reduced volume underlies regions of superior temporal primary and association auditory cortex and introduce a robust method for quantifying volumetric and white matter microstructural differences that can be applied to future studies of special populations.


Assuntos
Vias Auditivas/diagnóstico por imagem , Surdez/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Audição , Substância Branca/diagnóstico por imagem , Adulto , Anisotropia , Córtex Auditivo/diagnóstico por imagem , Córtex Auditivo/fisiopatologia , Vias Auditivas/fisiopatologia , Estudos de Casos e Controles , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/fisiopatologia , Surdez/congênito , Surdez/fisiopatologia , Surdez/psicologia , Feminino , Predisposição Genética para Doença , Audição/genética , Humanos , Masculino , Plasticidade Neuronal , Fenótipo , Valor Preditivo dos Testes , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiopatologia , Substância Branca/fisiopatologia , Adulto Jovem
9.
Dev Cogn Neurosci ; 13: 53-67, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26002721

RESUMO

Auditory selective attention is a critical skill for goal-directed behavior, especially where noisy distractions may impede focusing attention. To better understand the developmental trajectory of auditory spatial selective attention in an acoustically complex environment, in the current study we measured auditory event-related potentials (ERPs) across five age groups: 3-5 years; 10 years; 13 years; 16 years; and young adults. Using a naturalistic dichotic listening paradigm, we characterized the ERP morphology for nonlinguistic and linguistic auditory probes embedded in attended and unattended stories. We documented robust maturational changes in auditory evoked potentials that were specific to the types of probes. Furthermore, we found a remarkable interplay between age and attention-modulation of auditory evoked potentials in terms of morphology and latency from the early years of childhood through young adulthood. The results are consistent with the view that attention can operate across age groups by modulating the amplitude of maturing auditory early-latency evoked potentials or by invoking later endogenous attention processes. Development of these processes is not uniform for probes with different acoustic properties within our acoustically dense speech-based dichotic listening task. In light of the developmental differences we demonstrate, researchers conducting future attention studies of children and adolescents should be wary of combining analyses across diverse ages.


Assuntos
Envelhecimento , Atenção/fisiologia , Percepção Auditiva/fisiologia , Potenciais Evocados Auditivos , Fonética , Estimulação Acústica , Adolescente , Envelhecimento/fisiologia , Criança , Pré-Escolar , Testes com Listas de Dissílabos , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
10.
J Cogn Neurosci ; 26(12): 2682-90, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25000526

RESUMO

A growing body of research suggests that the predictive power of working memory (WM) capacity for measures of intellectual aptitude is due to the ability to control attention and select relevant information. Crucially, attentional mechanisms implicated in controlling access to WM are assumed to be domain-general, yet reports of enhanced attentional abilities in individuals with larger WM capacities are primarily within the visual domain. Here, we directly test the link between WM capacity and early attentional gating across sensory domains, hypothesizing that measures of visual WM capacity should predict an individual's capacity to allocate auditory selective attention. To address this question, auditory ERPs were recorded in a linguistic dichotic listening task, and individual differences in ERP modulations by attention were correlated with estimates of WM capacity obtained in a separate visual change detection task. Auditory selective attention enhanced ERP amplitudes at an early latency (ca. 70-90 msec), with larger P1 components elicited by linguistic probes embedded in an attended narrative. Moreover, this effect was associated with greater individual estimates of visual WM capacity. These findings support the view that domain-general attentional control mechanisms underlie the wide variation of WM capacity across individuals.


Assuntos
Atenção/fisiologia , Comportamento de Escolha/fisiologia , Potenciais Evocados Auditivos/fisiologia , Individualidade , Memória de Curto Prazo/fisiologia , Estimulação Acústica , Adolescente , Mapeamento Encefálico , Testes com Listas de Dissílabos , Eletroencefalografia , Feminino , Humanos , Linguística , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Detecção de Sinal Psicológico , Adulto Jovem
11.
Front Hum Neurosci ; 8: 177, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24723877

RESUMO

Brain reorganization associated with altered sensory experience clarifies the critical role of neuroplasticity in development. An example is enhanced peripheral visual processing associated with congenital deafness, but the neural systems supporting this have not been fully characterized. A gap in our understanding of deafness-enhanced peripheral vision is the contribution of primary auditory cortex. Previous studies of auditory cortex that use anatomical normalization across participants were limited by inter-subject variability of Heschl's gyrus. In addition to reorganized auditory cortex (cross-modal plasticity), a second gap in our understanding is the contribution of altered modality-specific cortices (visual intramodal plasticity in this case), as well as supramodal and multisensory cortices, especially when target detection is required across contrasts. Here we address these gaps by comparing fMRI signal change for peripheral vs. perifoveal visual stimulation (11-15° vs. 2-7°) in congenitally deaf and hearing participants in a blocked experimental design with two analytical approaches: a Heschl's gyrus region of interest analysis and a whole brain analysis. Our results using individually-defined primary auditory cortex (Heschl's gyrus) indicate that fMRI signal change for more peripheral stimuli was greater than perifoveal in deaf but not in hearing participants. Whole-brain analyses revealed differences between deaf and hearing participants for peripheral vs. perifoveal visual processing in extrastriate visual cortex including primary auditory cortex, MT+/V5, superior-temporal auditory, and multisensory and/or supramodal regions, such as posterior parietal cortex (PPC), frontal eye fields, anterior cingulate, and supplementary eye fields. Overall, these data demonstrate the contribution of neuroplasticity in multiple systems including primary auditory cortex, supramodal, and multisensory regions, to altered visual processing in congenitally deaf adults.

12.
J Neurosci ; 32(28): 9626-38, 2012 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-22787048

RESUMO

The developing brain responds to the environment by using statistical correlations in input to guide functional and structural changes-that is, the brain displays neuroplasticity. Experience shapes brain development throughout life, but neuroplasticity is variable from one brain system to another. How does the early loss of a sensory modality affect this complex process? We examined cross-modal neuroplasticity in anatomically defined subregions of Heschl's gyrus, the site of human primary auditory cortex, in congenitally deaf humans by measuring the fMRI signal change in response to spatially coregistered visual, somatosensory, and bimodal stimuli. In the deaf Heschl's gyrus, signal change was greater for somatosensory and bimodal stimuli than that of hearing participants. Visual responses in Heschl's gyrus, larger in deaf than hearing, were smaller than those elicited by somatosensory stimulation. In contrast to Heschl's gyrus, in the superior-temporal cortex visual signal was comparable to somatosensory signal. In addition, deaf adults perceived bimodal stimuli differently; in contrast to hearing adults, they were susceptible to a double-flash visual illusion induced by two touches to the face. Somatosensory and bimodal signal change in rostrolateral Heschl's gyrus predicted the strength of the visual illusion in the deaf adults in line with the interpretation that the illusion is a functional consequence of the altered cross-modal organization observed in deaf auditory cortex. Our results demonstrate that congenital and profound deafness alters how vision and somatosensation are processed in primary auditory cortex.


Assuntos
Córtex Auditivo/irrigação sanguínea , Mapeamento Encefálico , Surdez/patologia , Ilusões/fisiologia , Imageamento por Ressonância Magnética , Estimulação Acústica , Adulto , Análise de Variância , Córtex Auditivo/patologia , Surdez/congênito , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Oxigênio/sangue , Estimulação Luminosa , Psicofísica , Adulto Jovem
13.
Cereb Cortex ; 22(12): 2733-44, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22166765

RESUMO

As demonstrated by the attentional blink (AB) phenomenon, awareness for attended stimuli is governed by sharp capacity limits. We used a linguistic AB task to investigate the neural mechanisms that underlie failures of awareness, examining both event-related potentials and oscillatory brain activity to correctly reported and missed second targets (T2s) presented after a correctly reported first target (T1) in a rapid visual stream of distractors. Correctly reported targets occurring at a short lag (250 ms) after T1-within the classic AB period-elicited enhanced late gamma activity relative to incorrectly reported targets but showed no P300 modulation relative to missed targets. In contrast, correctly reported targets presented at a long lag (830 ms)-outside the classic AB period-elicited a greater P300 component but did not significantly modulate oscillatory activity. This double dissociation suggests that there are multiple neural mechanisms supporting awareness that may operate in parallel. Either the P300 or the gamma can index impairment in the cascade of processing leading to a target's entry into awareness. We conclude that the P300 and gamma activity reflect functionally distinct neural mechanisms, each of which plays an independent role in awareness.


Assuntos
Atenção/fisiologia , Intermitência na Atenção Visual/fisiologia , Ondas Encefálicas/fisiologia , Cognição/fisiologia , Sinais (Psicologia) , Potenciais Evocados P300/fisiologia , Mascaramento Perceptivo/fisiologia , Adolescente , Adulto , Transtornos Dissociativos , Feminino , Humanos , Linguística , Masculino , Plasticidade Neuronal/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
14.
J Cogn Neurosci ; 22(11): 2514-29, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19925179

RESUMO

An important question in the study of language is to what degree semantic and syntactic processes are automatic or controlled. This study employed an attentional blink (AB) paradigm to manipulate awareness in the processing of target words in order to assess automaticity in semantic and syntactic processing. In the semantic block, targets occurring both within and outside the AB period elicited an N400. However, N400 amplitude was significantly reduced during the AB period, and missed targets did not elicit an N400. In the syntactic block, ERPs to targets occurring outside the AB period revealed a late negative syntactic incongruency effect, whereas ERPs to targets occurring within the AB period showed no effect of incongruency. The semantic results support the argument that the N400 primarily indexes a controlled, postlexical process. Syntactic findings suggest that the ERP response to some syntactic violations depends on awareness and availability of attentional resources.


Assuntos
Atenção/fisiologia , Intermitência na Atenção Visual/fisiologia , Conscientização/fisiologia , Compreensão/fisiologia , Potenciais Evocados/fisiologia , Semântica , Adolescente , Adulto , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Psicolinguística , Tempo de Reação/fisiologia , Adulto Jovem
15.
J Cogn Neurosci ; 21(4): 669-83, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18564047

RESUMO

We used event-related potentials (ERPs) and gamma band oscillatory responses (GBRs) to examine whether intermodal attention operates early in the auditory, visual, and tactile modalities. To control for the effects of spatial attention, we spatially coregistered all stimuli and varied the attended modality across counterbalanced blocks in an intermodal selection task. In each block, participants selectively responded to either auditory, visual, or vibrotactile stimuli from the stream of intermodal events. Auditory and visual ERPs were modulated at the latencies of early cortical processing, but attention manifested later for tactile ERPs. For ERPs, auditory processing was modulated at the latency of the Na (29 msec), which indexes early cortical or thalamocortical processing and the subsequent P1 (90 msec) ERP components. Visual processing was modulated at the latency of the early phase of the C1 (62-72 msec) thought to be generated in the primary visual cortex and the subsequent P1 and N1 (176 msec). Tactile processing was modulated at the latency of the N160 (165 msec) likely generated in the secondary association cortex. Intermodal attention enhanced early sensory GBRs for all three modalities: auditory (onset 57 msec), visual (onset 47 msec), and tactile (onset 27 msec). Together, these results suggest that intermodal attention enhances neural processing relatively early in the sensory stream independent from differential effects of spatial and intramodal selective attention.


Assuntos
Atenção/fisiologia , Mapeamento Encefálico , Córtex Cerebral/fisiologia , Eletroencefalografia , Adolescente , Adulto , Humanos , Estimulação Física/métodos , Desempenho Psicomotor/fisiologia , Psicofísica , Tempo de Reação/fisiologia , Adulto Jovem
16.
Neuropsychologia ; 46(10): 2569-79, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18486157

RESUMO

Two hypotheses concerning cerebellar function and predictive behavior are the sensory prediction hypothesis and the timing hypothesis. The former postulates that the cerebellum is critical in generating expectancies regarding forthcoming sensory information. The latter postulates that this structure is critical in generating expectancies that are precisely timed; for example, the expected duration of an event or the time between events. As such, the timing hypothesis constitutes a more specific form of prediction. The present experiment contrasted these two hypotheses by examining the mismatch negativity (MMN) response in patients with cerebellar cortical atrophy and matched controls. While watching a silent movie, a stream of task-irrelevant sounds was presented. A standard sound was presented 60% of the time, whereas the remaining sounds deviated from the standard on one of four dimensions: duration, intensity, pitch, or location. The timing between stimuli was either periodic or aperiodic. Based on the sensory prediction hypothesis, the MMN for the patients should be abnormal across all four dimensions. In contrast, the timing hypothesis would predict a selective impairment of the duration MMN. Moreover, the timing hypothesis would also predict that the enhancement of the MMN observed in controls when the stimuli are presented periodically should be attenuated in the patients. Compared to controls, the patients exhibited a delayed latency in the MMN to duration deviants and a similar trend for the intensity deviants, while pitch and location MMNs did not differ between groups. Periodicity had limited and somewhat inconsistent effects. The present results are at odds with a general role for the cerebellum in sensory prediction and provide partial support for the timing hypothesis.


Assuntos
Percepção Auditiva/fisiologia , Variação Contingente Negativa/fisiologia , Potenciais Evocados Auditivos/fisiologia , Degenerações Espinocerebelares/fisiopatologia , Estimulação Acústica/métodos , Adulto , Idoso , Análise de Variância , Atenção , Limiar Auditivo , Mapeamento Encefálico , Estudos de Casos e Controles , Discriminação Psicológica , Eletroencefalografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Tempo de Reação/fisiologia
17.
Neurosci Lett ; 335(3): 171-4, 2003 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-12531460

RESUMO

We used the mismatch negativity event-related potential to examine how spatial location and feature variation affect the capacity of the auditory system to automatically respond to pairs of rapid (180 ms apart) acoustic changes within a single tone. When a tone first deviated from a standard tone in source location and then in its duration, we found independent responses to both deviations for right but not left field stimuli. In contrast, when the first deviation was in pitch and the second in duration, only the first deviation elicited a response, regardless of presentation side. These results suggest that information from either side of space is asymmetrically processed even in a free-field, and that the extent of the temporal window of integration is not a fixed property of the auditory system.


Assuntos
Percepção Auditiva/fisiologia , Potenciais Evocados Auditivos/fisiologia , Discriminação da Altura Tonal/fisiologia , Localização de Som/fisiologia , Estimulação Acústica , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino
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