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1.
Cereb Cortex ; 32(17): 3752-3762, 2022 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-34902861

RESUMEN

Event-related potentials (ERPs) associated with the involuntary orientation of (bottom-up) attention toward an unexpected sound are of larger amplitude in high dream recallers (HR) than in low dream recallers (LR) during passive listening, suggesting different attentional functioning. We measured bottom-up and top-down attentional performance and their cerebral correlates in 18 HR (11 women, age = 22.7 years, dream recall frequency = 5.3 days with a dream recall per week) and 19 LR (10 women, age = 22.3, DRF = 0.2) using EEG and the Competitive Attention Task. Between-group differences were found in ERPs but not in behavior. The results show that HR present larger ERPs to distracting sounds than LR even during active listening, arguing for enhanced bottom-up processing of irrelevant sounds. HR also presented larger contingent negative variation during target expectancy and P3b to target sounds than LR, speaking for an enhanced recruitment of top-down attention. The attentional balance seems preserved in HR since their performances are not altered, but possibly at a higher resource cost. In HR, increased bottom-up processes would favor dream recall through awakening facilitation during sleep and enhanced top-down processes may foster dream recall through increased awareness and/or short-term memory stability of dream content.


Asunto(s)
Potenciales Evocados , Sueño , Adulto , Percepción Auditiva , Electroencefalografía , Femenino , Humanos , Memoria a Corto Plazo , Recuerdo Mental , Adulto Joven
2.
J Exp Child Psychol ; 227: 105584, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36413871

RESUMEN

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.


Asunto(s)
Clase Social , Sonido , Preescolar , Humanos , Estimulación Acústica/métodos , Aprendizaje , Cognición
3.
Eur J Neurosci ; 55(5): 1215-1231, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35112420

RESUMEN

Attention operates through top-down and bottom-up processes, and a balance between these processes is crucial for daily tasks. Imperilling such balance could explain ageing-associated attentional problems such as exacerbated distractibility. In this study, we aimed to characterize this enhanced distractibility by investigating the impact of ageing upon event-related components associated with top-down and bottom-up attentional processes. MEG and EEG data were acquired from 14 older and 14 younger healthy adults while performing a task that conjointly evaluates top-down and bottom-up attention. Event-related components were analysed on sensor and source levels. In comparison with the younger group, the older mainly displayed (1) reduced target anticipation processes (reduced CMV), (2) increased early target processing (larger P50 but smaller N1) and (3) increased processing of early distracting sounds (larger N1 but reduced P3a), followed by a (4) prolonged reorientation towards the main task (larger RON). Taken together, our results suggest that the enhanced distractibility in ageing could stem from top-down deficits, in particular from reduced inhibitory and reorientation processes.


Asunto(s)
Envejecimiento , Electroencefalografía , Adulto , Humanos , Tiempo de Reacción
4.
J Sleep Res ; 31(5): e13557, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35102655

RESUMEN

Several factors influencing dream recall frequency (DRF) have been identified, but some remain poorly understood. One way to study DRF is to compare cognitive processes in low and high dream recallers (LR and HR). According to the arousal-retrieval model, long-term memory encoding of a dream requires wakefulness while its multisensory short-term memory is still alive. Previous studies showed contradictory results concerning short-term memory differences between LR and HR. It has also been found that extreme DRFs are associated with different electrophysiological traits related to attentional processes. However, to date, there is no evidence for attentional differences between LR and HR at the behavioural level. To further investigate attention and working memory in HR and LR, we used a newly-developed challenging paradigm called "MEMAT" (for MEMory and ATtention), which allows the study of selective attention and working memory interaction during memory encoding of non-verbal auditory stimuli. We manipulated the difficulties of the distractor to ignore and of the memory task. The performance of the two groups were not differentially impacted by working memory load. However, HR were slower and less accurate in the presence of a hard rather than easy to-ignore distractor, while LR were much less impacted by the distractor difficulty. Therefore, we show behavioural evidence towards less resistance to hard-to-ignore distractors in HR. Using a challenging task, we show for the first time, attentional differences between HR and LR at the behavioural level. The impact of auditory attention and working memory on dream recall is discussed.


Asunto(s)
Memoria a Corto Plazo , Recuerdo Mental , Atención/fisiología , Humanos , Memoria a Corto Plazo/fisiología , Recuerdo Mental/fisiología , Vigilia/fisiología
5.
Brain Topogr ; 34(3): 384-401, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33606142

RESUMEN

A growing number of studies investigate brain anatomy in migraine using voxel- (VBM) and surface-based morphometry (SBM), as well as diffusion tensor imaging (DTI). The purpose of this article is to identify consistent patterns of anatomical alterations associated with migraine. First, 19 migraineurs without aura and 19 healthy participants were included in a brain imaging study. T1-weighted MRIs and DTI sequences were acquired and analyzed using VBM, SBM and tract-based spatial statistics. No significant alterations of gray matter (GM) volume, cortical thickness, cortical gyrification, sulcus depth and white-matter tract integrity could be observed. However, migraineurs displayed decreased white matter (WM) volume in the left superior longitudinal fasciculus. Second, a systematic review of the literature employing VBM, SBM and DTI was conducted to investigate brain anatomy in migraine. Meta-analysis was performed using Seed-based d Mapping via permutation of subject images (SDM-PSI) on GM volume, WM volume and cortical thickness data. Alterations of GM volume, WM volume, cortical thickness or white-matter tract integrity were reported in 72%, 50%, 56% and 33% of published studies respectively. Spatial distribution and direction of the disclosed effects were highly inconsistent across studies. The SDM-PSI analysis revealed neither significant decrease nor significant increase of GM volume, WM volume or cortical thickness in migraine. Overall there is to this day no strong evidence of specific brain anatomical alterations reliably associated to migraine. Possible explanations of this conflicting literature are discussed. Trial registration number: NCT02791997, registrated February 6th, 2015.


Asunto(s)
Trastornos Migrañosos , Sustancia Blanca , Encéfalo/diagnóstico por imagen , Imagen de Difusión Tensora , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Trastornos Migrañosos/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen
6.
Cereb Cortex ; 30(2): 696-707, 2020 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-31219542

RESUMEN

Auditory attention operates through top-down (TD) and bottom-up (BU) mechanisms that are supported by dorsal and ventral brain networks, respectively, with the main overlap in the lateral prefrontal cortex (lPFC). A good TD/BU balance is essential to be both task-efficient and aware of our environment, yet it is rarely investigated. Oscillatory activity is a novel method to probe the attentional dynamics with evidence that gamma activity (>30 Hz) could signal BU processing and thus would be a good candidate to support the activation of the ventral BU attention network. Magnetoencephalography data were collected from 21 young adults performing the competitive attention task, which enables simultaneous investigation of BU and TD attentional mechanisms. Distracting sounds elicited an increase in gamma activity in regions of the BU ventral network. TD attention modulated these gamma responses in regions of the inhibitory cognitive control system: the medial prefrontal and anterior cingulate cortices. Finally, distracting-sound-induced gamma activity was synchronous between the auditory cortices and several distant brain regions, notably the lPFC. We provide novel insight into the role of gamma activity 1) in supporting the activation of the ventral BU attention network and 2) in subtending the TD/BU attention balance in the PFC.


Asunto(s)
Atención/fisiología , Percepción Auditiva/fisiología , Ritmo Gamma , Lóbulo Parietal/fisiología , Corteza Prefrontal/fisiología , Estimulación Acústica , Adulto , Corteza Auditiva/fisiología , Femenino , Humanos , Magnetoencefalografía , Masculino , Vías Nerviosas/fisiología , Adulto Joven
7.
Child Dev ; 92(4): e716-e737, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33825204

RESUMEN

Distractibility is the propensity to behaviorally react to irrelevant information. Although children are more distractible the younger they are, the precise contribution of attentional and motor components to distractibility and their developmental trajectories have not been characterized yet. We used a new behavioral paradigm to identify the developmental dynamics of components contributing to distractibility in a large cohort of French participants balanced, between age groups, in gender and socioeconomic status (N = 352; age: 6-25). Results reveal that each measure of these components, namely voluntary attention, distraction, impulsivity, and motor control, present a distinct maturational timeline. In young children, increased distractibility is mostly the result of reduced sustained attention capacities and enhanced distraction, whereas in teenagers, it is the result of decreased motor control and increased impulsivity.


Asunto(s)
Atención , Conducta Impulsiva , Adolescente , Adulto , Niño , Preescolar , Estudios de Cohortes , Humanos , Tiempo de Reacción , Adulto Joven
8.
Cereb Cortex ; 29(9): 3606-3617, 2019 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-30295717

RESUMEN

Attention and saccadic adaptation (SA) are critical components of visual perception, the former enhancing sensory processing of selected objects, the latter maintaining the eye movements accuracy toward them. Recent studies propelled the hypothesis of a tight functional coupling between these mechanisms, possibly due to shared neural substrates. Here, we used magnetoencephalography to investigate for the first time the neurophysiological bases of this coupling and of SA per se. We compared visual discrimination performance of 12 healthy subjects before and after SA. Eye movements and magnetic signals were recorded continuously. Analyses focused on gamma band activity (GBA) during the pretarget period of the discrimination and the saccadic tasks. We found that GBA increases after SA. This increase was found in the right hemisphere for both postadaptation saccadic and discrimination tasks. For the latter, GBA also increased in the left hemisphere. We conclude that oculomotor plasticity involves GBA modulation within an extended neural network which persists after SA, suggesting a possible role of gamma oscillations in the coupling between SA and attention.


Asunto(s)
Adaptación Fisiológica , Atención/fisiología , Encéfalo/fisiología , Ritmo Gamma , Desempeño Psicomotor/fisiología , Movimientos Sacádicos , Percepción Visual/fisiología , Adulto , Discriminación en Psicología/fisiología , Medidas del Movimiento Ocular , Femenino , Humanos , Magnetoencefalografía , Masculino
9.
Neuroimage ; 185: 164-180, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30336252

RESUMEN

The P3a observed after novel events is an event-related potential comprising an early fronto-central phase and a late fronto-parietal phase. It has classically been considered to reflect the attention processing of distracting stimuli. However, novel sounds can lead to behavioral facilitation as much as behavioral distraction. This illustrates the duality of the orienting response which includes both an attentional and an arousal component. Using a paradigm with visual or auditory targets to detect and irrelevant unexpected distracting sounds to ignore, we showed that the facilitation effect by distracting sounds is independent of the target modality and endures more than 1500 ms. These results confirm that the behavioral facilitation observed after distracting sounds is related to an increase in unspecific phasic arousal on top of the attentional capture. Moreover, the amplitude of the early phase of the P3a to distracting sounds positively correlated with subjective arousal ratings, contrary to other event-related potentials. We propose that the fronto-central early phase of the P3a would index the arousing properties of distracting sounds and would be linked to the arousal component of the orienting response. Finally, we discuss the relevance of the P3a as a marker of distraction.


Asunto(s)
Atención/fisiología , Encéfalo/fisiología , Potenciales Relacionados con Evento P300/fisiología , Estimulación Acústica , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Adulto Joven
10.
Cereb Cortex ; 25(11): 4126-34, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24925773

RESUMEN

There is growing evidence that auditory selective attention operates via distinct facilitatory and inhibitory mechanisms enabling selective enhancement and suppression of sound processing, respectively. The lateral prefrontal cortex (LPFC) plays a crucial role in the top-down control of selective attention. However, whether the LPFC controls facilitatory, inhibitory, or both attentional mechanisms is unclear. Facilitatory and inhibitory mechanisms were assessed, in patients with LPFC damage, by comparing event-related potentials (ERPs) to attended and ignored sounds with ERPs to these same sounds when attention was equally distributed to all sounds. In control subjects, we observed 2 late frontally distributed ERP components: a transient facilitatory component occurring from 150 to 250 ms after sound onset; and an inhibitory component onsetting at 250 ms. Only the facilitatory component was affected in patients with LPFC damage: this component was absent when attending to sounds delivered in the ear contralateral to the lesion, with the most prominent decreases observed over the damaged brain regions. These findings have 2 important implications: (i) they provide evidence for functionally distinct facilitatory and inhibitory mechanisms supporting late auditory selective attention; (ii) they show that the LPFC is involved in the control of the facilitatory mechanisms of auditory attention.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/etiología , Percepción Auditiva/fisiología , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/patología , Potenciales Evocados Auditivos/fisiología , Corteza Prefrontal/fisiopatología , Estimulación Acústica , Mapeo Encefálico , Electroencefalografía , Femenino , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética , Magnetoencefalografía , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Tiempo de Reacción , Estadísticas no Paramétricas
11.
Brain Topogr ; 28(3): 423-36, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-24531985

RESUMEN

Attention improves the processing of specific information while other stimuli are disregarded. A good balance between bottom-up (attentional capture by unexpected salient stimuli) and top-down (selection of relevant information) mechanisms is crucial to be both task-efficient and aware of our environment. Only few studies have explored how an isolated unexpected task-irrelevant stimulus outside the attention focus can disturb the top-down attention mechanisms necessary to the good performance of the ongoing task, and how these top-down mechanisms can modulate the bottom-up mechanisms of attentional capture triggered by an unexpected event. We recorded scalp electroencephalography in 18 young adults performing a new paradigm measuring distractibility and assessing both bottom-up and top-down attention mechanisms, at the same time. Increasing task load in top-down attention was found to reduce early processing of the distracting sound, but not bottom-up attentional capture mechanisms nor the behavioral distraction cost in reaction time. Moreover, the impact of bottom-up attentional capture by distracting sounds on target processing was revealed as a delayed latency of the N100 sensory response to target sounds mirroring increased reaction times. These results provide crucial information into how bottom-up and top-down mechanisms dynamically interact and compete in the human brain, i.e. on the precarious balance between voluntary attention and distraction.


Asunto(s)
Atención/fisiología , Percepción Auditiva/fisiología , Encéfalo/fisiología , Estimulación Acústica , Adulto , Electroencefalografía , Potenciales Evocados/fisiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Tiempo de Reacción , Adulto Joven
12.
bioRxiv ; 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38659916

RESUMEN

Many people, and particularly those diagnosed with ADHD, report difficulties maintaining attention and proneness to distraction during classroom learning. However, the behavioral, neural and physiological basis of attention in realistic learning contexts is not well understood, since current clinical and scientific tools used for evaluating and quantifying the constructs of "distractibility" and "inattention", are removed from the real-life experience in organic classrooms. Here we introduce a novel Virtual Reality (VR) platform for studying students' brain activity and physiological responses as they immerse in realistic frontal classroom learning. Using this approach, we studied whether adults with and without ADHD (N=49) exhibit differences in neurophysiological metrics associated with sustained attention, such as speech-tracking of the teacher's voice, power of alpha-oscillations and levels of arousal, as well as responses to potential disturbances by background sound-events in the classroom. Under these ecological conditions, we find that adults with ADHD exhibit higher auditory neural response to background sounds relative to their control-peers, which also contributed to explaining variance in the severity of ADHD symptoms, together with higher power of alpha-oscillations and more frequent gaze-shifts around the classroom. These results are in-line with higher sensitivity to irrelevant stimuli in the environment and increased mind-wandering/boredom. At the same time, both groups exhibited similar learning outcomes and showed similar neural tracking of the teacher's speech. This suggests that in this context, attention may not operate as a zero-sum game and that allocating some resources to irrelevant stimuli does not always detract from performing the task at hand. Given the dire need for more objective, dimensional and ecologically-valid measures of attention and its real-life deficits, this work provides new insights into the neurophysiological manifestations of attention and distraction experienced in real-life contexts, while challenging some prevalent notions regarding the nature of attentional challenges experienced by those with ADHD.

13.
J Exp Psychol Gen ; 152(12): 3403-3417, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37589702

RESUMEN

Distractibility determines the propensity to have one's attention captured by irrelevant information; it relies on a balance between voluntary and involuntary attention. We report a cross-sectional study that uses the competitive attention test to characterize patterns of attention across the adult life span from 21 to 86 years old. Several distractibility components were measured in 186 participants distributed within seven age groups. Results indicate that distractibility components follow distinct trajectories with aging: Voluntary orienting remains stable from 21 to 86 years old, sustained attention decreases after 30 years old, distraction progressively increases between 26 and 86 years old, and impulsivity is lower in older compared to younger adults. Increased distractibility in older age thus seems to result from a dominance of involuntary over voluntary attention processes, whose detrimental effect on performance is partly compensated by enhanced motor control. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Envejecimiento , Trastornos del Conocimiento , Adulto , Humanos , Anciano , Adulto Joven , Persona de Mediana Edad , Anciano de 80 o más Años , Estudios Transversales , Atención
14.
Eur J Neurosci ; 36(7): 2996-3004, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22780698

RESUMEN

We employed an electroencephalography paradigm manipulating predictive context to dissociate the neural dynamics of anticipatory mechanisms. Subjects either detected random targets or targets preceded by a predictive sequence of three distinct stimuli. The last stimulus in the three-stimulus sequence (decisive stimulus) did not require any motor response but 100% predicted a subsequent target event. We showed that predictive context optimises target processing via the deployment of distinct anticipatory mechanisms at different times of the predictive sequence. Prior to the occurrence of the decisive stimulus, enhanced attentional preparation was manifested by reductions in the alpha oscillatory activities over the visual cortices, resulting in facilitation of processing of the decisive stimulus. Conversely, the subsequent 100% predictable target event did not reveal the deployment of attentional preparation in the visual cortices, but elicited enhanced motor preparation mechanisms, indexed by an increased contingent negative variation and reduced mu oscillatory activities over the motor cortices before movement onset. The present results provide evidence that anticipation operates via different attentional and motor preparation mechanisms by selectively pre-activating task-dependent brain areas as the predictability gradually increases.


Asunto(s)
Anticipación Psicológica/fisiología , Adulto , Ritmo alfa , Atención/fisiología , Ritmo beta , Encéfalo/fisiología , Toma de Decisiones/fisiología , Potenciales Evocados , Femenino , Humanos , Masculino , Estimulación Luminosa
15.
Atten Percept Psychophys ; 84(3): 739-759, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35106682

RESUMEN

You are on the phone, walking down a street. This daily situation calls for selective attention, allowing you to ignore surrounding irrelevant sounds, while trying to encode in memory the relevant information from the phone. Attention and memory are indeed two cognitive functions that are interacting constantly. However, their interaction is not yet well characterized during sound-sequence encoding. We independently manipulated both selective attention and working memory in a delayed-matching-to-sample of two tone-series, played successively in one ear. During the first melody presentation (memory encoding), weakly or highly distracting melodies were played in the other ear. Detection of the difference between the two comparison melodies could be easy or difficult, requiring low- or high-precision encoding, i.e., low or high memory load. Sixteen non-musician and 16 musician participants performed this new task. As expected, both groups of participants were less accurate in the difficult memory task and in difficult-to-ignore distractor conditions. Importantly, an interaction between memory-task difficulty and distractor difficulty was found in both groups. Non-musicians presented less difference between easy and difficult-to-ignore distractors in the difficult than in the easy memory task. On the contrary, musicians, with better performance than non-musicians, showed a greater difference between easy and difficult-to-ignore distractors in the difficult than in the easy memory task. In a second experiment including trials without a distractor, we could show that these effects are in line with the cognitive load theory. Taken together, these results speak for shared cognitive resources between working memory and attention during sound-sequence encoding.


Asunto(s)
Atención , Memoria a Corto Plazo , Cognición , Humanos , Sonido
16.
Heliyon ; 8(6): e09631, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35734572

RESUMEN

Numerous studies showed that task-evoked pupil dilation is an objective marker of cognitive activity and listening effort. However, these studies differ in their experimental and analysis methods. Whereas most studies focus on a single method, the present study sought to compare different pupil-dilation data analysis methods, including different normalization techniques, baseline periods, and baseline durations, in order to assess their influence on the outcomes of pupillometry results obtained in an auditory task. To that purpose, we used pupillometry data recorded in response to words in noise in hearing-impaired individuals. The start-time of the baseline relative to stimulus timing turned out to have a significant influence on conclusions. In particular, a significant interaction in the effects of signal-to-noise ratio and hearing-aid use on pupil dilation was observed when the baseline period used started early relative to the word-an effect likely related to anticipatory, pre-stimulus cognitive processes, such as attention mobilization. This was the case even with only correct-response trials included in analyses, so that any confounding effect of performance in the word-repetition task was eliminated. Different normalization methods and baseline durations showed similar results, however the use of z-score transformation homogenized variability across conditions without affecting the qualitative aspect of the results. The consistency of results regardless of normalization methods, and the fact that differences in pupil dilation and subjective measures of listening effort could be observed despite perfect performance in the task, underlines the relevance of pupillometry as an objective measure of listening effort.

17.
Neuron ; 109(13): 2047-2074, 2021 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-34237278

RESUMEN

Despite increased awareness of the lack of gender equity in academia and a growing number of initiatives to address issues of diversity, change is slow, and inequalities remain. A major source of inequity is gender bias, which has a substantial negative impact on the careers, work-life balance, and mental health of underrepresented groups in science. Here, we argue that gender bias is not a single problem but manifests as a collection of distinct issues that impact researchers' lives. We disentangle these facets and propose concrete solutions that can be adopted by individuals, academic institutions, and society.


Asunto(s)
Equidad de Género , Investigadores , Sexismo , Universidades/organización & administración , Femenino , Humanos , Masculino , Investigación/organización & administración
18.
J Cogn Neurosci ; 22(11): 2491-502, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19925193

RESUMEN

Human electrophysiological research is generally restricted to scalp EEG, magneto-encephalography, and intracranial electrophysiology. Here we examine a unique patient cohort that has undergone decompressive hemicraniectomy, a surgical procedure wherein a portion of the calvaria is removed for several months during which time the scalp overlies the brain without intervening bone. We quantify the differences in signals between electrodes over areas with no underlying skull and scalp EEG electrodes over the intact skull in the same subjects. Signals over the hemicraniectomy have enhanced amplitude and greater task-related power at higher frequencies (60-115 Hz) compared with signals over skull. We also provide evidence of a metric for trial-by-trial EMG/EEG coupling that is effective over the hemicraniectomy but not intact skull at frequencies >60 Hz. Taken together, these results provide evidence that the hemicraniectomy model provides a means for studying neural dynamics in humans with enhanced spatial and temporal resolution.


Asunto(s)
Mapeo Encefálico , Corteza Cerebral/fisiología , Electroencefalografía , Lateralidad Funcional/fisiología , Estimulación Acústica/métodos , Parpadeo/fisiología , Lesiones Encefálicas/fisiopatología , Lesiones Encefálicas/cirugía , Corteza Cerebral/cirugía , Craniectomía Descompresiva/métodos , Electromiografía/métodos , Potenciales Evocados Auditivos/fisiología , Femenino , Análisis de Fourier , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Presión Intracraneal/fisiología , Masculino , Movimiento/fisiología , Cuero Cabelludo , Factores de Tiempo , Tomografía Computarizada por Rayos X/métodos
19.
Neuroimage ; 50(1): 277-84, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20026231

RESUMEN

It is unknown whether facilitation and inhibition of stimulus processing represent one or two mechanisms in auditory attention. We performed electrophysiological experiments in humans to address these two competing hypothesis. Participants performed an attention task under low or high memory load. Facilitation and inhibition were measured by recording electrophysiological responses to attended and ignored sounds and comparing them to responses to these same sounds when attention was considered to be equally distributed towards all sounds. We observed two late frontally distributed components: a negative one in response to attended sounds, and a positive one to ignored sounds. These two frontally distributed responses had distinct timing and scalp topographies and were differentially affected by memory load. Taken together these results provide evidence that attention-mediated top-down control reflects the activity of distinct facilitation and inhibition mechanisms.


Asunto(s)
Atención/fisiología , Percepción Auditiva/fisiología , Encéfalo/fisiología , Memoria/fisiología , Estimulación Acústica , Adolescente , Adulto , Análisis de Varianza , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Inhibición Neural/fisiología , Pruebas Neuropsicológicas , Tiempo de Reacción , Cuero Cabelludo , Factores de Tiempo , Adulto Joven
20.
Sci Rep ; 10(1): 13430, 2020 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-32778710

RESUMEN

Attention and saccadic eye movements are critical components of visual perception. Recent studies proposed the hypothesis of a tight coupling between saccadic adaptation (SA) and attention: SA increases the processing speed of unpredictable stimuli, while increased attentional load boosts SA. Moreover, their cortical substrates partially overlap. Here, we investigated for the first time whether this coupling in the reactive/exogenous modality is specific to the orienting system of attention. We studied the effect of adaptation of reactive saccades (RS), elicited by the double-step paradigm, on exogenous orienting, measured using a Posner-like detection paradigm. In 18 healthy subjects, the attentional benefit-the difference in reaction time to targets preceded by informative versus uninformative cues-in a control exposure condition was subtracted from that of each adaptation exposure condition (backward and forward); then, this cue benefit difference was compared between the pre- and post-exposure phases. We found that, the attentional benefit significantly increased for cued-targets presented in the left hemifield after backward adaptation and for cued-targets presented in the right hemifield after forward adaptation. These findings provide strong evidence in humans for a coupling between RS adaptation and attention, possibly through the activation of a common neuronal pool.


Asunto(s)
Atención/fisiología , Orientación Espacial/fisiología , Movimientos Sacádicos/fisiología , Adaptación Fisiológica , Adulto , Señales (Psicología) , Femenino , Voluntarios Sanos , Humanos , Masculino , Orientación/fisiología , Estimulación Luminosa/métodos , Tiempo de Reacción/fisiología , Percepción Visual/fisiología
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