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1.
Adv Exp Med Biol ; 1232: 69-75, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893396

RESUMO

We investigated the relationship between cerebral oxygenation (COX) and skin blood flow (SkBF) at the left frontal lobes of 10 healthy young men during progressive hypoxia (∼ -1 h at each of 21%, 18%, 15%, and 12% of inspired oxygen [FiO2]). Acute hypotension was manipulated by a thigh-cuff-release technique, where a pressure of 220 mmHg was applied at both thigh muscles for 3 min and the cuff was immediately released to induce acute hypotension. While the resting baseline for COX before the thigh-cuff release manipulation decreased gradually with the reduction of FiO2 (P < 0.05), the resting baseline for SkBF, mean arterial blood pressure (MAP), and cutaneous vascular conductance (CVC) were unaffected by FiO2 (P > 0.05). The acute hypotension that was induced by the thigh-cuff release decreased COX, SkBF, MAP, and CVC; thereafter, these values recovered toward their baseline values. During the hypotension phase, while the time to the nadir values for COX slowed progressively with reductions in FiO2 (P < 0.05), those for SkBF, MAP, and CVC were unaffected by FiO2 (P > 0.05). These results suggest that COX may not be associated with SkBF for the protocol or with the subjects in the present study.


Assuntos
Circulação Cerebrovascular , Lobo Frontal , Hipotensão , Pele , Adulto , Velocidade do Fluxo Sanguíneo , Lobo Frontal/fisiologia , Hemodinâmica , Humanos , Hipotensão/fisiopatologia , Masculino , Pele/irrigação sanguínea , Adulto Jovem
2.
Dev Sci ; 23(1): e12891, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31359565

RESUMO

Asymmetric patterns of frontal brain electrical activity reflect approach and avoidance tendencies, with stability of relative right activation associated with withdrawal emotions/motivation and left hemisphere activation linked with approach and positive affect. However, considerable shifts in approach/avoidance-related lateralization have been reported for children not targeted because of extreme temperament. In this study, dynamic effects of frontal electroencephalogram (EEG) power within and across hemispheres were examined throughout early childhood. Specifically, EEG indicators at 5, 10, 24, 36, 48, and 72 months-of-age (n = 410) were analyzed via a hybrid of difference score and panel design models, with baseline measures and subsequent time-to-time differences modeled as potentially influencing all subsequent amounts of time-to-time change (i.e., predictively saturated). Infant sex was considered as a moderator of dynamic developmental effects, with temperament attributes measured at 5 months examined as predictors of EEG hemisphere development. Overall, change in left and right frontal EEG power predicted declining subsequent change in the same hemisphere, with effects on the opposing neurobehavioral system enhancing later growth. Infant sex moderated the pattern of within and across-hemisphere effects, wherein for girls more prominent left hemisphere influences on the right hemisphere EEG changes were noted and right hemisphere effects were more salient for boys. Largely similar patterns of temperament prediction were observed for the left and the right EEG power changes, with limited sex differences in links between temperament and growth parameters. Results were interpreted in the context of comparable analyses using parietal power values, which provided evidence for unique frontal effects.


Assuntos
Eletroencefalografia/métodos , Lobo Frontal/fisiologia , Criança , Feminino , Lobo Frontal/crescimento & desenvolvimento , Humanos , Lactente , Masculino , Motivação , Caracteres Sexuais , Temperamento/fisiologia
3.
Brain Lang ; 199: 104696, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31655417

RESUMO

Morphological awareness, the ability to manipulate the smallest units of meaning, is critical for Chinese literacy. This is because Chinese characters typically reflect the morphemic, or morpho-syllabic units of language. Yet, the neurocognitive mechanisms underlying Chinese speakers' morphological processing remain understudied. Proficient readers (N = 14) completed morphological and phonological judgment tasks in Chinese, in both auditory and visual modalities, during fMRI imaging. Key to our inquiry were patterns of activation in left temporal regions, especially the superior temporal gyrus, which is critical for phonological processing and reading success. The findings revealed that morphological tasks elicited robust activation in superior and middle temporal regions commonly associated with automated phonological and lexico-semantic analyses. In contrast, the rhyme judgment task elicited greater activation in left frontal lobe regions, reflecting the analytical complexity of sound-to-print mapping in Chinese. The findings suggest that left temporal regions are sensitive to salient morpho-syllabic characteristics of a given language.


Assuntos
Grupo com Ancestrais do Continente Asiático/psicologia , Lobo Frontal/fisiologia , Leitura , Lobo Temporal/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Julgamento , Masculino , Semântica
4.
PLoS Comput Biol ; 15(10): e1006667, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31609973

RESUMO

A fundamental and recurrent question in systems neuroscience is that of assessing what variables are encoded by a given population of neurons. Such assessments are often challenging because neurons in one brain area may encode multiple variables, and because neuronal representations might be categorical or non-categorical. These issues are particularly pertinent to the representation of decision variables in the orbitofrontal cortex (OFC)-an area implicated in economic choices. Here we present a new algorithm to assess whether a neuronal representation is categorical or non-categorical, and to identify the encoded variables if the representation is indeed categorical. The algorithm is based on two clustering procedures, one variable-independent and the other variable-based. The two partitions are then compared through adjusted mutual information. The present algorithm overcomes limitations of previous approaches and is widely applicable. We tested the algorithm on synthetic data and then used it to examine neuronal data recorded in the primate OFC during economic decisions. Confirming previous assessments, we found the neuronal representation in OFC to be categorical in nature. We also found that neurons in this area encode the value of individual offers, the binary choice outcome and the chosen value. In other words, during economic choice, neurons in the primate OFC encode decision variables in a categorical way.


Assuntos
Comportamento de Escolha/fisiologia , Biologia Computacional/métodos , Tomada de Decisões/fisiologia , Algoritmos , Animais , Análise por Conglomerados , Lobo Frontal/fisiologia , Macaca mulatta , Modelos Teóricos , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Recompensa
5.
Behav Neurol ; 2019: 1410425, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31565094

RESUMO

Previous studies have shown that the neural mechanisms underlying visual spatial attention rely on top-down control information from the frontal and parietal cortexes, which ultimately amplifies sensory processing of stimulus occurred at the attended location relative to those at unattended location. However, the modulations of effective brain networks in response to stimulus at attended and unattended location are not yet clear. In present study, we collected event-related potentials (ERPs) from 15 subjects during a visual spatial attention task, and a partial directed coherence (PDC) method was used to construct alpha-band effective brain networks of two conditions (targets at attended and nontargets at unattended location). Flow gain mapping, effective connectivity pattern, and graph measures including clustering coefficient (C), characteristic path length (L), global efficiency (E global), and local efficiency (E local) were compared between two conditions. Flow gain mapping showed that the frontal region seemed to serve as the main source of information transmission in response to targets at attended location while the parietal region served as the main source in nontarget condition. Effective connectivity pattern indicated that in response to targets, there existed obvious top-down connections from the frontal, temporal, and parietal cortexes to the visual cortex compared with in response to nontargets. Graph theory analysis was used to quantify the topographical properties of the brain networks, and results revealed that in response to targets, the brain networks were characterized by significantly smaller characteristic path length and larger global efficiency than in response to nontargets. Our findings suggested that smaller characteristic path length and larger global efficiency could facilitate global integration of information and provide a substrate for more efficient perceptual processing of targets at attended location compared with processing of nontargets at ignored location, which revealed the neural mechanisms underlying visual spatial attention from the perspective of effective brain networks and graph theory for the first time and opened new vistas to interpret a cognitive process.


Assuntos
Ritmo alfa/fisiologia , Processamento Espacial/fisiologia , Percepção Visual/fisiologia , Atenção/fisiologia , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Feminino , Lobo Frontal/fisiologia , Humanos , Masculino , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Estimulação Luminosa , Adulto Jovem
6.
Handb Clin Neurol ; 163: 165-177, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590728

RESUMO

Cognitive control refers to our ability to choose courses of thought and action that achieve our goals over habitual but contextually inappropriate ones. Hierarchical control problems are those in which multiple goals or contextual contingency must be managed at once and related to one another. In the open-ended complexity of the real world, hierarchical control arguably characterizes most of the problems faced by our control systems. And, it is these cases of hierarchical control where patients with damage to executive systems are most apt to fail, even those that perform well on simplified laboratory tasks. In this chapter, we consider the functional organization of frontal brain systems that support hierarchical cognitive control. We focus on two particular cases of hierarchical control. First, we discuss a line of work testing how managing multiple contingencies en route to a response relates to processing along the rostrocaudal axis of frontal cortex. Second, we consider cases of sequential tasks that require monitoring and behaving according to a series of tasks performed in time. In this latter case, we focus on the particular role of rostrolateral prefrontal cortex. We conclude with considerations of future directions of basic and clinically relevant research in this domain.


Assuntos
Cognição/fisiologia , Função Executiva/fisiologia , Lobo Frontal/fisiologia , Humanos , Vias Neurais/fisiologia
7.
Handb Clin Neurol ; 163: 19-34, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590730

RESUMO

Patients with focal frontal lobe damage have long been a crucial source of information about the role of this region in human behavior. This method remains the only means to provide inferentially powerful loss-of-function evidence for many regions within the human frontal lobes. This chapter demonstrates modern focal lesion research methods, focusing on specific subregions within prefrontal cortex, and their contributions to widely studied aspects of executive function and decision-making. Examples of such studies are reviewed in detail, to demonstrate the strengths, limitations, and logic of lesion methods. The evidence provided by such studies is considered in relation to converging evidence from other cognitive neuroscience methods. The tensions between modular and network views of prefrontal function are also addressed. Lesion studies straddle fundamental and clinical neuroscience, allowing basic advances in this area to be readily translated to psychiatric and neurologic disorders. This unique position, as well as the ability to test causal claims, explains the staying power of this classic approach to understanding the brain basis of behavior.


Assuntos
Atenção/fisiologia , Lesões Encefálicas/fisiopatologia , Tomada de Decisões/fisiologia , Função Executiva/fisiologia , Lobo Frontal/fisiologia , Lobo Frontal/lesões , Lobo Frontal/fisiopatologia , Humanos , Testes Neuropsicológicos
8.
Handb Clin Neurol ; 163: 197-219, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590731

RESUMO

Executive functions (EFs) include high-order cognitive abilities such as working memory, inhibitory control, cognitive flexibility, planning, reasoning, and problem solving. EFs enable humans to achieve goals, adapt to novel everyday life situations, and manage social interactions. Traditionally EFs have been associated with frontal lobe functioning. More recent evidence shows that posterior and subcortical regions also play a crucial role in EF processing, especially in the integration of sensory information and emotion. This chapter reviews the variety of EFs and their neural underpinning, based on lesion mapping and neuroimaging studies, as well as the evidence for rehabilitation interventions, neuropsychological assessment based on standard and ecologically valid tests, development, and genetic predisposition for recovery of executive functions after brain injury. Taken together, the EFs are critical for unique human abilities and more careful analyses of their subcomponents may help the development of targeted translational interventions to improve them.


Assuntos
Cognição/fisiologia , Função Executiva/fisiologia , Lobo Frontal/fisiologia , Humanos , Memória de Curto Prazo/fisiologia , Testes Neuropsicológicos , Resolução de Problemas/fisiologia
9.
Handb Clin Neurol ; 163: 257-280, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590734

RESUMO

Being able to flexibly regulate one's emotions is critical for adaptive functioning across the life span. The importance of emotion regulation for human cognition has been reflected in the marked increase in the amount of psychologic research on emotion and its regulation in the past two decades. In this chapter, we review theoretical and empirical advances in this research, with a particular focus on the neural bases of emotion regulation. We begin with a brief overview of the field at present and provide a general primer on the behavioral and neuroimaging methods used to study emotion regulation. We then outline the brain regions involved in both triggering and modulating affect, and how they may change throughout development and into old age. Finally, we conclude with a roadmap for the future study of emotion regulation, in particular focusing on how to integrate measures with high ecologic validity (e.g., experience sampling, social emotion regulation) with neuroimaging techniques.


Assuntos
Envelhecimento/psicologia , Lobo Frontal/fisiologia , Mapeamento Encefálico , Emoções/fisiologia , Lobo Frontal/diagnóstico por imagem , Humanos , Neuroimagem
10.
Handb Clin Neurol ; 163: 281-294, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590735

RESUMO

Neurons throughout frontal cortex show robust responses to rewards, but a challenge is determining the specific function served by these different reward signals. Most neuropsychiatric disorders involve dysfunction of circuits between frontal cortex and subcortical structures, such as the striatum. There are multiple frontostriatal loops, and different neuropsychiatric disorders involve different loops to greater or lesser extents. Understanding the role of reward in each of these different circuits is a necessary step in developing novel treatments for these disorders. This chapter summarizes the recent literature that has identified the role of reward in different subregions of the frontal cortex. Orbitofrontal cortex integrates information about multiple aspects of expected rewards in order to derive their value, which can then be used to decide between alternative potential rewards. Neurons in anterior cingulate cortex encode the difference between the expected reward and the actual outcome. This information is useful for learning, since it can ensure that behavior changes when the outcome was not anticipated. Reward also affects signals in lateral prefrontal cortex related to attention and response selection, ensuring that behaviors are optimally prioritized. Finally, the chapter discusses how reward signals contribute to social processing and autonomic control.


Assuntos
Lobo Frontal/fisiologia , Neurônios/fisiologia , Recompensa , Animais , Atenção/fisiologia , Tomada de Decisões/fisiologia , Humanos , Vias Neurais/fisiologia
11.
Handb Clin Neurol ; 163: 317-332, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590738

RESUMO

Computational models of frontal function have made important contributions to understanding how the frontal lobes support a wide range of important functions, in their interactions with other brain areas including, critically, the basal ganglia (BG). We focus here on the specific case of how different frontal areas support goal-directed, motivated decision-making, by representing three essential types of information: possible plans of action (in more dorsal and lateral frontal areas), affectively significant outcomes of those action plans (in ventral, medial frontal areas including the orbital frontal cortex), and the overall utility of a given plan compared to other possible courses of action (in anterior cingulate cortex). Computational models of goal-directed action selection at multiple different levels of analysis provide insight into the nature of learning and processing in these areas and the relative contributions of the frontal cortex versus the BG. The most common neurologic disorders implicate these areas, and understanding their precise function and modes of dysfunction can contribute to the new field of computational psychiatry, within the broader field of computational neuroscience.


Assuntos
Simulação por Computador , Lobo Frontal/fisiologia , Modelos Neurológicos , Motivação/fisiologia , Humanos
12.
Handb Clin Neurol ; 163: 333-347, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590739

RESUMO

The human brain is organized into specialized functional brain networks. Some networks are dedicated to early sensory processing, and others to generating motor outputs. Yet, the bulk of the human brain's functional networks is actually dedicated to control processes. The two control networks most important for the impressive repertoire of control-related behaviors that humans are able to instantiate and maintain are the frontoparietal and cinguloopercular networks. We provide evidence that these two control networks largely contribute to nonoverlapping domains of control. These networks largely have been studied using fMRI, which is sensitive only to infraslow activity. Complementary electrophysiological techniques have provided evidence that these networks manifest at substantially faster frequencies (delta-alpha band), supporting their role in coordination of whole-brain functional network activity. Both the frontoparietal and cinguloopercular networks demonstrate protracted development, supporting increases in control-related performance. Recent studies from our lab indicate these control networks exhibit measurable individual specificity, highlighting the importance of individualized paradigms in neuroimaging studies to advance our understanding of typical and atypical control network function throughout the life span.


Assuntos
Lobo Frontal/fisiologia , Rede Nervosa/fisiologia , Mapeamento Encefálico , Lobo Frontal/diagnóstico por imagem , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Rede Nervosa/diagnóstico por imagem
13.
Handb Clin Neurol ; 163: 369-389, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590742

RESUMO

Healthy aging is associated with numerous deficits in cognitive function, which have been attributed to changes within the prefrontal cortex (PFC). This chapter summarizes some of the most prominent cognitive changes associated with age-related alterations in the anatomy and physiology of the PFC. Specifically, aging of the PFC results in deficient aspects of cognitive control, including sustained attention, selective attention, inhibitory control, working memory, and multitasking abilities. Yet, not all cognitive functions associated with the PFC exhibit age-related declines, such as arithmetic, comprehension, emotion perception, and emotional control. Moreover, not all older adults exhibit declines in cognition. Multiple life-course and lifestyle factors, as well as genetics, play a role in the trajectory of cognitive performance across the life span. Thus many adults retain cognitive function well into advanced age. Moreover, the brain remains plastic throughout life and there is increasing evidence that most age-related declines in cognition can be remediated by various methods such as physical exercise, cognitive training, or noninvasive brain stimulation. Overall, because cognitive aging is associated with numerous life-course and lifestyle factors, successful aging likely begins in early life, while maintaining cognition or remediating declines is a life-long process.


Assuntos
Envelhecimento/fisiologia , Cognição/fisiologia , Função Executiva/fisiologia , Lobo Frontal/fisiologia , Atenção/fisiologia , Humanos , Memória de Curto Prazo/fisiologia
14.
Handb Clin Neurol ; 163: 457-472, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590746

RESUMO

Impairments of social behavior constitute common symptoms of frontal lobe dysfunction and are frequent consequences of damage to the frontal lobe. In this chapter we define and describe social behavioral deficits that include mentalizing (e.g., theory of mind, empathy), social self-regulation, social self-awareness, and social problem solving, and discuss how intervention research might address these deficits. Three stages of neurologic illness are emphasized: the early recovery stage after frontal lobe damage, chronic recovery phases of recovery from frontal lobe damage, and progressive decline from frontal neurodegenerative disease. Each of these stages presents unique challenges in identifying and remediating social impairments that constitute vital areas of adjustment for patients and their families within home and community settings.


Assuntos
Empatia/fisiologia , Lobo Frontal/fisiologia , Comportamento Social , Percepção Social , Teoria da Mente/fisiologia , Humanos , Testes Neuropsicológicos , Resolução de Problemas/fisiologia
15.
Handb Clin Neurol ; 163: 473-483, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31590747

RESUMO

The frontal lobe plays a crucial role in human motor behavior. It is one of the last areas of the brain to mature, especially the prefrontal regions. After a brief historical perspective on the perceived dichotomy between the view of the brain as a static organ and that of a plastic, constantly changing structure, we discuss the stability/plasticity dilemma including examples of documented cortical reorganization taking place at multiple spatial and temporal scales. We pose that while plasticity is needed for motor learning, stability of the system is necessary for storage and maintenance of memorized skills. We discuss how this plasticity/stability dilemma is resolved along the life span and after a brain injury. We then examine the main challenges that clinicians have to overcome to promote recovery of function in patients with brain lesions, including attempts to use neurostimulation techniques as adjuvant to training-based customary neurorehabilitation.


Assuntos
Lesões Encefálicas/fisiopatologia , Lobo Frontal/fisiologia , Plasticidade Neuronal/fisiologia , Recuperação de Função Fisiológica/fisiologia , Humanos , Aprendizagem/fisiologia , Reabilitação Neurológica
16.
Nat Neurosci ; 22(11): 1871-1882, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31591558

RESUMO

Sensorimotor control during overt movements is characterized in terms of three building blocks: a controller, a simulator and a state estimator. We asked whether the same framework could explain the control of internal states in the absence of movements. Recently, it was shown that the brain controls the timing of future movements by adjusting an internal speed command. We trained monkeys in a novel task in which the speed command had to be dynamically controlled based on the timing of a sequence of flashes. Recordings from the frontal cortex provided evidence that the brain updates the internal speed command after each flash based on the error between the timing of the flash and the anticipated timing of the flash derived from a simulated motor plan. These findings suggest that cognitive control of internal states may be understood in terms of the same computational principles as motor control.


Assuntos
Lobo Frontal/fisiologia , Modelos Neurológicos , Movimento/fisiologia , Percepção do Tempo/fisiologia , Animais , Macaca mulatta , Masculino , Desempenho Psicomotor/fisiologia
17.
Nat Neurosci ; 22(12): 2066-2077, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31659343

RESUMO

When learning the value of actions in volatile environments, humans often make seemingly irrational decisions that fail to maximize expected value. We reasoned that these 'non-greedy' decisions, instead of reflecting information seeking during choice, may be caused by computational noise in the learning of action values. Here using reinforcement learning models of behavior and multimodal neurophysiological data, we show that the majority of non-greedy decisions stem from this learning noise. The trial-to-trial variability of sequential learning steps and their impact on behavior could be predicted both by blood oxygen level-dependent responses to obtained rewards in the dorsal anterior cingulate cortex and by phasic pupillary dilation, suggestive of neuromodulatory fluctuations driven by the locus coeruleus-norepinephrine system. Together, these findings indicate that most behavioral variability, rather than reflecting human exploration, is due to the limited computational precision of reward-guided learning.


Assuntos
Tomada de Decisões/fisiologia , Aprendizagem/fisiologia , Recompensa , Adulto , Comportamento de Escolha/fisiologia , Feminino , Lobo Frontal/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Modelos Neurológicos , Neuroimagem , Pupila/fisiologia , Adulto Jovem
18.
J Vis ; 19(11): 13, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31561251

RESUMO

During self-motion through an environment, our sensory systems are confronted with a constant flow of information from different modalities. To successfully navigate, self-induced sensory signals have to be dissociated from externally induced sensory signals. Previous studies have suggested that the processing of self-induced sensory information is modulated by means of predictive coding mechanisms. However, the neural correlates of processing self-induced sensory information from different modalities during self-motion are largely unknown. Here, we asked if and how the processing of visually simulated self-motion and/or associated auditory stimuli is modulated by self-controlled action. Participants were asked to actively reproduce a previously observed simulated self-displacement (path integration). Blood oxygen level-dependent (BOLD) activation during this path integration was compared with BOLD activation during a condition in which we passively replayed the exact sensory stimulus that had been produced by the participants in previous trials. We found supramodal BOLD suppression in parietal and frontal regions. Remarkably, BOLD contrast in sensory areas was enhanced in a modality-specific manner. We conclude that the effect of action on sensory processing is strictly dependent on the respective behavioral task and its relevance.


Assuntos
Percepção Auditiva/fisiologia , Lobo Frontal/fisiologia , Processos Mentais/fisiologia , Percepção de Movimento/fisiologia , Sensação/fisiologia , Estimulação Acústica , Adulto , Cognição/fisiologia , Feminino , Fixação Ocular/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Movimento/fisiologia , Estimulação Luminosa , Adulto Jovem
19.
Nat Hum Behav ; 3(12): 1263-1270, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31477910

RESUMO

Attending to our inner world is a fundamental cognitive phenomenon1-3, yet its neural underpinnings remain largely unknown. Neuroimaging evidence implicates the default network (DN) and frontoparietal control network (FPCN)4; however, the electrophysiological basis for the interaction between these networks is unclear. Here we recorded intracranial electroencephalogram from DN and FPCN electrodes implanted in individuals undergoing presurgical monitoring for refractory epilepsy. Subjects performed an attention task during which they attended to tones (that is, externally directed attention) or ignored the tones and thought about whatever came to mind (that is, internally directed attention). Given the emerging role of theta band connectivity in attentional processes5,6, we examined the theta power correlation between DN and two subsystems of the FPCN as a function of attention states. We found increased connectivity between DN and FPCNA during internally directed attention compared to externally directed attention, which positively correlated with attention ratings. There was no statistically significant difference between attention states in the connectivity between DN and FPCNB. Our results indicate that enhanced theta band connectivity between the DN and FPCNA is a core electrophysiological mechanism that underlies internally directed attention.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Lobo Frontal/fisiologia , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Ritmo Teta , Adolescente , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Eletroencefalografia , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Ritmo Teta/fisiologia , Adulto Jovem
20.
Psychol Addict Behav ; 33(7): 626-636, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31497986

RESUMO

Exerting self-control depletes capacity for future self-control, which can promote greater alcohol use. However, certain populations may be more susceptible to these effects of depleted self-control capacity. For example, individuals with lower alcohol sensitivity (i.e., requiring more drinks to experience the effects of alcohol) are a high-risk group who are likely to engage in hazardous alcohol use and develop an alcohol use disorder. Those lower in alcohol sensitivity also exhibit heightened motivational reactivity in response to alcohol-related cues, which may be enhanced following exertion of self-control. However, whether drinkers lower in alcohol sensitivity are at higher risk for exhibiting greater motivations toward alcohol-related cues after exerting self-control is unclear. The current research examined the role of alcohol sensitivity in predicting approach motivation following exertion of self-control. It was expected drinkers exerting self-control would exhibit greater orientation toward rewarding cues, particularly after viewing alcohol-related cues. However, we predicted this pattern would be most prominent among drinkers lower in alcohol sensitivity. Experiment 1 supported these hypotheses, with lower alcohol sensitivity predicting greater approach motivation among drinkers required to exert self-control prior to viewing alcohol-related compared to neutral cues. Experiment 2 aimed to replicate these findings by assessing asymmetrical frontal cortical activation, an index of approach motivation. Drinkers with lower alcohol sensitivity exhibited greater relative left frontal cortical activation, consistent with approach motivation, while viewing alcohol-related cues following exertion of self-control. Results have implications for interventions aimed at identifying those at risk for greater alcohol motivations during states of mental exhaustion. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Depressores do Sistema Nervoso Central/farmacologia , Sinais (Psicologia) , Etanol/farmacologia , Lobo Frontal/fisiologia , Lateralidade Funcional/fisiologia , Motivação/fisiologia , Autocontrole , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
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