Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.029
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Cell ; 187(6): 1476-1489.e21, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38401541

RESUMO

Attention filters sensory inputs to enhance task-relevant information. It is guided by an "attentional template" that represents the stimulus features that are currently relevant. To understand how the brain learns and uses templates, we trained monkeys to perform a visual search task that required them to repeatedly learn new attentional templates. Neural recordings found that templates were represented across the prefrontal and parietal cortex in a structured manner, such that perceptually neighboring templates had similar neural representations. When the task changed, a new attentional template was learned by incrementally shifting the template toward rewarded features. Finally, we found that attentional templates transformed stimulus features into a common value representation that allowed the same decision-making mechanisms to deploy attention, regardless of the identity of the template. Altogether, our results provide insight into the neural mechanisms by which the brain learns to control attention and how attention can be flexibly deployed across tasks.


Assuntos
Atenção , Tomada de Decisões , Aprendizagem , Lobo Parietal , Recompensa , Animais , Haplorrinos
2.
Proc Natl Acad Sci U S A ; 120(18): e2216792120, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37104474

RESUMO

Acetylcholine (ACh) in cortical neural circuits mediates how selective attention is sustained in the presence of distractors and how flexible cognition adjusts to changing task demands. The cognitive domains of attention and cognitive flexibility might be differentially supported by the M1 muscarinic acetylcholine receptor (mAChR) subtype. Understanding how M1 mAChR mechanisms support these cognitive subdomains is of highest importance for advancing novel drug treatments for conditions with altered attention and reduced cognitive control including Alzheimer's disease or schizophrenia. Here, we tested this question by assessing how the subtype-selective M1 mAChR positive allosteric modulator (PAM) VU0453595 affects visual search and flexible reward learning in nonhuman primates. We found that allosteric potentiation of M1 mAChRs enhanced flexible learning performance by improving extradimensional set shifting, reducing latent inhibition from previously experienced distractors and reducing response perseveration in the absence of adverse side effects. These procognitive effects occurred in the absence of apparent changes of attentional performance during visual search. In contrast, nonselective ACh modulation using the acetylcholinesterase inhibitor (AChEI) donepezil improved attention during visual search at doses that did not alter cognitive flexibility and that already triggered gastrointestinal cholinergic side effects. These findings illustrate that M1 mAChR positive allosteric modulation enhances cognitive flexibility without affecting attentional filtering of distraction, consistent with M1 activity boosting the effective salience of relevant over irrelevant objects specifically during learning. These results suggest that M1 PAMs are versatile compounds for enhancing cognitive flexibility in disorders spanning schizophrenia and Alzheimer's diseases.


Assuntos
Acetilcolinesterase , Doença de Alzheimer , Animais , Regulação Alostérica/fisiologia , Colinérgicos/farmacologia , Acetilcolina/farmacologia , Cognição , Doença de Alzheimer/tratamento farmacológico , Primatas , Receptor Muscarínico M1
3.
Proc Natl Acad Sci U S A ; 120(28): e2220523120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37399398

RESUMO

The human prefrontal cortex (PFC) constitutes the structural basis underlying flexible cognitive control, where mixed-selective neural populations encode multiple task features to guide subsequent behavior. The mechanisms by which the brain simultaneously encodes multiple task-relevant variables while minimizing interference from task-irrelevant features remain unknown. Leveraging intracranial recordings from the human PFC, we first demonstrate that competition between coexisting representations of past and present task variables incurs a behavioral switch cost. Our results reveal that this interference between past and present states in the PFC is resolved through coding partitioning into distinct low-dimensional neural states; thereby strongly attenuating behavioral switch costs. In sum, these findings uncover a fundamental coding mechanism that constitutes a central building block of flexible cognitive control.


Assuntos
Cognição , Córtex Pré-Frontal , Humanos
4.
Proc Natl Acad Sci U S A ; 120(50): e2221510120, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38064507

RESUMO

Effort-based decisions, in which people weigh potential future rewards against effort costs required to achieve those rewards involve both cognitive and physical effort, though the mechanistic relationship between them is not yet understood. Here, we use an individual differences approach to isolate and measure the computational processes underlying effort-based decisions and test the association between cognitive and physical domains. Patch foraging is an ecologically valid reward rate maximization problem with well-developed theoretical tools. We developed the Effort Foraging Task, which embedded cognitive or physical effort into patch foraging, to quantify the cost of both cognitive and physical effort indirectly, by their effects on foraging choices. Participants chose between harvesting a depleting patch, or traveling to a new patch that was costly in time and effort. Participants' exit thresholds (reflecting the reward they expected to receive by harvesting when they chose to travel to a new patch) were sensitive to cognitive and physical effort demands, allowing us to quantify the perceived effort cost in monetary terms. The indirect sequential choice style revealed effort-seeking behavior in a minority of participants (preferring high over low effort) that has apparently been missed by many previous approaches. Individual differences in cognitive and physical effort costs were positively correlated, suggesting that these are perceived and processed in common. We used canonical correlation analysis to probe the relationship of task measures to self-reported affect and motivation, and found correlations of cognitive effort with anxiety, cognitive function, behavioral activation, and self-efficacy, but no similar correlations with physical effort.


Assuntos
Tomada de Decisões , Esforço Físico , Humanos , Tomada de Decisões/fisiologia , Esforço Físico/fisiologia , Individualidade , Cognição/fisiologia , Recompensa , Motivação
5.
J Neurosci ; 44(36)2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39134417

RESUMO

Cognitive flexibility represents the capacity to switch among different mental schemes, providing an adaptive advantage to a changing environment. The neural underpinnings of this executive function have been deeply studied in humans through fMRI, showing that the left inferior frontal cortex (IFC) and the left inferior parietal lobule (IPL) are crucial. Here, we investigated the inhibitory-excitatory balance in these regions by means of γ-aminobutyric acid (GABA+) and glutamate + glutamine (Glx), measured with magnetic resonance spectroscopy, during a cognitive flexibility task and its relationship with the performance level and the local task-induced blood oxygenation level-dependent (BOLD) response in 40 young (18-35 years; 26 female) and 40 older (18-35 years; 21 female) human adults. As the IFC and the IPL are richly connected regions, we also examined whole-brain effects associated with their local metabolic activity. Results did not show absolute metabolic modulations associated with flexibility performance, but the performance level was related to the direction of metabolic modulation in the IPL with opposite patterns in young and older individuals. The individual inhibitory-excitatory balance modulation showed an inverse relationship with the local BOLD response in the IPL. Finally, the modulation of inhibitory-excitatory balance in IPL was related to whole-brain effects only in older individuals. These findings show disparities in the metabolic mechanisms underlying cognitive flexibility in young and older adults and their association with the performance level and BOLD response. Such metabolic differences are likely to play a role in executive functioning during aging and specifically in cognitive flexibility.


Assuntos
Envelhecimento , Cognição , Imageamento por Ressonância Magnética , Humanos , Feminino , Masculino , Adulto , Adulto Jovem , Adolescente , Cognição/fisiologia , Envelhecimento/fisiologia , Encéfalo/fisiologia , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Função Executiva/fisiologia , Mapeamento Encefálico , Ácido gama-Aminobutírico/metabolismo , Espectroscopia de Ressonância Magnética , Ácido Glutâmico/metabolismo
6.
J Neurosci ; 44(33)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-38955488

RESUMO

Adaptive behaviors require the ability to resolve conflicting information caused by the processing of incompatible sensory inputs. Prominent theories of attention have posited that early selective attention helps mitigate cognitive interference caused by conflicting sensory information by facilitating the processing of task-relevant sensory inputs and filtering out behaviorally irrelevant information. Surprisingly, many recent studies that investigated the role of early selective attention on conflict mitigation have failed to provide positive evidence. Here, we examined changes in the selectivity of early visuospatial attention in male and female human subjects performing an attention-cueing Eriksen flanker task, where they discriminated the shape of a visual target surrounded by congruent or incongruent distractors. We used the inverted encoding model to reconstruct spatial representations of visual selective attention from the topographical patterns of amplitude modulations in alpha band oscillations in scalp EEG (∼8-12 Hz). We found that the fidelity of the alpha-based spatial reconstruction was significantly higher in the incongruent compared with the congruent condition. Importantly, these conflict-related modulations in the reconstruction fidelity occurred at a much earlier time window than those of the lateralized posterior event-related potentials associated with target selection and distractor suppression processes, as well as conflict-related modulations in the frontocentral negative-going wave and midline-frontal theta oscillations (∼3-7 Hz), thought to track executive control functions. Taken together, our data suggest that conflict resolution is supported by the cascade of neural processes underlying early selective visuospatial attention and frontal executive functions that unfold over time.


Assuntos
Atenção , Percepção Espacial , Percepção Visual , Humanos , Masculino , Feminino , Atenção/fisiologia , Adulto Jovem , Adulto , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Eletroencefalografia , Estimulação Luminosa/métodos , Conflito Psicológico , Sinais (Psicologia) , Potenciais Evocados/fisiologia
7.
J Neurosci ; 44(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37963765

RESUMO

Recently, multi-voxel pattern analysis has verified that information can be removed from working memory (WM) via three distinct operations replacement, suppression, or clearing compared to information being maintained ( Kim et al., 2020). While univariate analyses and classifier importance maps in Kim et al. (2020) identified brain regions that contribute to these operations, they did not elucidate whether these regions represent the operations similarly or uniquely. Using Leiden-community-detection on a sample of 55 humans (17 male), we identified four brain networks, each of which has a unique configuration of multi-voxel activity patterns by which it represents these WM operations. The visual network (VN) shows similar multi-voxel patterns for maintain and replace, which are highly dissimilar from suppress and clear, suggesting this network differentiates whether an item is held in WM or not. The somatomotor network (SMN) shows a distinct multi-voxel pattern for clear relative to the other operations, indicating the uniqueness of this operation. The default mode network (DMN) has distinct patterns for suppress and clear, but these two operations are more similar to each other than to maintain and replace, a pattern intermediate to that of the VN and SMN. The frontoparietal control network (FPCN) displays distinct multi-voxel patterns for each of the four operations, suggesting that this network likely plays an important role in implementing these WM operations. These results indicate that the operations involved in removing information from WM can be performed in parallel by distinct brain networks, each of which has a particular configuration by which they represent these operations.


Assuntos
Encéfalo , Memória de Curto Prazo , Masculino , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Mapeamento Encefálico , Estimulação Luminosa , Imageamento por Ressonância Magnética/métodos
8.
Annu Rev Neurosci ; 40: 99-124, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28375769

RESUMO

In spite of its familiar phenomenology, the mechanistic basis for mental effort remains poorly understood. Although most researchers agree that mental effort is aversive and stems from limitations in our capacity to exercise cognitive control, it is unclear what gives rise to those limitations and why they result in an experience of control as costly. The presence of these control costs also raises further questions regarding how best to allocate mental effort to minimize those costs and maximize the attendant benefits. This review explores recent advances in computational modeling and empirical research aimed at addressing these questions at the level of psychological process and neural mechanism, examining both the limitations to mental effort exertion and how we manage those limited cognitive resources. We conclude by identifying remaining challenges for theoretical accounts of mental effort as well as possible applications of the available findings to understanding the causes of and potential solutions for apparent failures to exert the mental effort required of us.


Assuntos
Cognição/fisiologia , Tomada de Decisões/fisiologia , Função Executiva/fisiologia , Motivação/fisiologia , Córtex Pré-Frontal/fisiologia , Humanos , Recompensa
9.
Brain ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864500

RESUMO

The fate of deprived sensory cortices - visual regions in the blind and auditory regions in the deaf - exemplifies the extent to which experience can change brain regions. These regions are frequently seen to activate during tasks involving other sensory modalities, leading many accounts to infer that these regions have started processing sensory information of other modalities. However, such observations can also imply that these regions are now activating to any task event regardless of the sensory modality. Activating to task events, irrespective of the sensory modality involved, is a feature of the multiple-demands (MD) network. These are a common set of regions within the frontal and parietal cortices that activate in response to any kind of control demand. Thus, demands as diverse as attention, perceptual difficulty, rule-switching, updating working memory, inhibiting responses, decision-making, and difficult arithmetic - all activate these same set of regions that are thought to instantiate domain-general cognitive control and underpin fluid intelligence. We investigated if deprived sensory cortices, or foci within them, become part of the MD network. We tested if the same foci within the visual regions of the blind and auditory regions of the deaf activated to different control demands. We found that control demands related to updating auditory working memory, difficult tactile decisions, time-duration judgments, and sensorimotor-speed - all activated the entire bilateral occipital regions in the blind but not in the sighted. These occipital regions in the blind were the only regions outside the canonical fronto-parietal MD regions to show such activation to multiple control demands. Further, compared to the sighted, these occipital regions in the blind had higher functional connectivity with fronto-parietal MD regions. Early deaf, in contrast, did not activate their auditory regions to different control demands, showing that auditory regions do not become MD regions in the deaf. We suggest that visual regions in the blind do not take a new sensory role but become part of the MD network, and this is not a response of all deprived sensory cortices but a feature unique to the visual regions.

10.
Brain ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869168

RESUMO

Control of actions allows adaptive, goal-directed behaviour. The basal ganglia, including the subthalamic nucleus, are thought to play a central role in dynamically controlling actions through recurrent negative feedback loops with the cerebral cortex. Here, we summarize recent translational studies that used deep brain stimulation to record neural activity from and apply electrical stimulation to the subthalamic nucleus in people with Parkinson's disease. These studies have elucidated spatial, spectral and temporal features of the neural mechanisms underlying the controlled delay of actions in cortico-subthalamic networks and demonstrated their causal effects on behaviour in distinct processing windows. While these mechanisms have been conceptualized as control signals for suppressing impulsive response tendencies in conflict tasks and as decision threshold adjustments in value-based and perceptual decisions, we propose a common framework linking decision-making, cognition and movement. Within this framework subthalamic deep brain stimulation can lead to suboptimal choices by reducing the time that patients take for deliberation before committing to an action. However, clinical studies have consistently shown that the occurrence of impulse control disorders is reduced, not increased, after subthalamic deep brain stimulation surgery. This apparent contradiction can be reconciled when recognizing the multifaceted nature of impulsivity, its underlying mechanisms and modulation by treatment. While subthalamic deep brain stimulation renders patients susceptible to making decisions without proper forethought, this can be disentangled from effects related to dopamine comprising sensitivity to benefits vs. costs, reward delay aversion and learning from outcomes. Alterations in these dopamine-mediated mechanisms are thought to underlie the development of impulse control disorders, and can be relatively spared with reduced dopaminergic medication after subthalamic deep brain stimulation. Together, results from studies using deep brain stimulation as an experimental tool have improved our understanding of action control in the human brain and have important implications for treatment of patients with Neurological disorders.

11.
Brain ; 147(2): 352-371, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37703295

RESUMO

Executive functions are high-level cognitive processes involving abilities such as working memory/updating, set-shifting and inhibition. These complex cognitive functions are enabled by interactions among widely distributed cognitive networks, supported by white matter tracts. Executive impairment is frequent in neurological conditions affecting white matter; however, whether specific tracts are crucial for normal executive functions is unclear. We review causal and correlation evidence from studies that used direct electrical stimulation during awake surgery for gliomas, voxel-based and tract-based lesion-symptom mapping, and diffusion tensor imaging to explore associations between the integrity of white matter tracts and executive functions in healthy and impaired adults. The corpus callosum was consistently associated with all executive processes, notably its anterior segments. Both causal and correlation evidence showed prominent support of the superior longitudinal fasciculus to executive functions, notably to working memory. More specifically, strong evidence suggested that the second branch of the superior longitudinal fasciculus is crucial for all executive functions, especially for flexibility. Global results showed left lateralization for verbal tasks and right lateralization for executive tasks with visual demands. The frontal aslant tract potentially supports executive functions, however, additional evidence is needed to clarify whether its involvement in executive tasks goes beyond the control of language. Converging evidence indicates that a right-lateralized network of tracts connecting cortical and subcortical grey matter regions supports the performance of tasks assessing response inhibition, some suggesting a role for the right anterior thalamic radiation. Finally, correlation evidence suggests a role for the cingulum bundle in executive functions, especially in tasks assessing inhibition. We discuss these findings in light of current knowledge about the functional role of these tracts, descriptions of the brain networks supporting executive functions and clinical implications for individuals with brain tumours.


Assuntos
Neoplasias Encefálicas , Substância Branca , Adulto , Humanos , Função Executiva/fisiologia , Substância Branca/patologia , Neoplasias Encefálicas/patologia , Imagem de Tensor de Difusão , Vigília
12.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38044467

RESUMO

English learners (ELs) are a rapidly growing population in schools in the United States with limited experience and proficiency in English. To better understand the path for EL's academic success in school, it is important to understand how EL's brain systems are used for academic learning in English. We studied, in a cohort of Hispanic middle-schoolers (n = 45, 22F) with limited English proficiency and a wide range of reading and math abilities, brain network properties related to academic abilities. We applied a method for localizing brain regions of interest (ROIs) that are group-constrained, yet individually specific, to test how resting state functional connectivity between regions that are important for academic learning (reading, math, and cognitive control regions) are related to academic abilities. ROIs were selected from task localizers probing reading and math skills in the same participants. We found that connectivity across all ROIs, as well as connectivity of just the cognitive control ROIs, were positively related to measures of reading skills but not math skills. This work suggests that cognitive control brain systems have a central role for reading in ELs. Our results also indicate that an individualized approach for localizing brain function may clarify brain-behavior relationships.


Assuntos
Encéfalo , Instituições Acadêmicas , Humanos , Encéfalo/diagnóstico por imagem , Leitura
13.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38183181

RESUMO

The prevalence of physically inactive lifestyles in modern society raises concerns about the potential association with poor brain health, particularly in the lateral prefrontal cortex, which is crucial for human prosocial behavior. Here, we explored the relationship between physical activity and prosocial behavior, focusing on potential neural markers, including intra-brain functional connectivity and inter-brain synchrony in the lateral prefrontal cortex. Forty participants, each paired with a stranger, completed two experimental conditions in a randomized order: (i) face-to-face and (ii) face stimulus (eye-to-eye contact with a face stimulus of a fictitious person displayed on the screen). Following each condition, participants played economic games with either their partner or an assumed person displayed on the screen. Neural activity in the lateral prefrontal cortex was recorded by functional near-infrared spectroscopy hyperscanning. Sparse multiset canonical correlation analysis showed that a physically inactive lifestyle was covaried with poorer reciprocity, greater trust, shorter decision-making time, and weaker intra-brain connectivity in the dorsal lateral prefrontal cortex and poorer inter-brain synchrony in the ventral lateral prefrontal cortex. These associations were observed exclusively in the face-to-face condition. Our findings suggest that a physically inactive lifestyle may alter human prosocial behavior by impairing adaptable prosocial decision-making in response to social factors through altered intra-brain functional connectivity and inter-brain synchrony.


Assuntos
Altruísmo , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Mapeamento Encefálico/métodos , Exercício Físico
14.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38244562

RESUMO

Theoretical models suggest that executive functions rely on both domain-general and domain-specific processes. Supporting this view, prior brain imaging studies have revealed that executive activations converge and diverge within broadly characterized brain networks. However, the lack of precise anatomical mappings has impeded our understanding of the interplay between domain-general and domain-specific processes. To address this challenge, we used the high-resolution multimodal magnetic resonance imaging approach of the Human Connectome Project to scan participants performing 3 canonical executive tasks: n-back, rule switching, and stop signal. The results reveal that, at the individual level, different executive activations converge within 9 domain-general territories distributed in frontal, parietal, and temporal cortices. Each task exhibits a unique topography characterized by finely detailed activation gradients within domain-general territory shifted toward adjacent resting-state networks; n-back activations shift toward the default mode, rule switching toward dorsal attention, and stop signal toward cingulo-opercular networks. Importantly, the strongest activations arise at multimodal neurobiological definitions of network borders. Matching results are seen in circumscribed regions of the caudate nucleus, thalamus, and cerebellum. The shifting peaks of local gradients at the intersection of task-specific networks provide a novel mechanistic insight into how partially-specialized networks interact with neighboring domain-general territories to generate distinct executive functions.


Assuntos
Conectoma , Função Executiva , Humanos , Função Executiva/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Núcleo Caudado , Atenção/fisiologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia
15.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38314589

RESUMO

Sentence comprehension is highly practiced and largely automatic, but this belies the complexity of the underlying processes. We used functional neuroimaging to investigate garden-path sentences that cause difficulty during comprehension, in order to unpack the different processes used to support sentence interpretation. By investigating garden-path and other types of sentences within the same individuals, we functionally profiled different regions within the temporal and frontal cortices in the left hemisphere. The results revealed that different aspects of comprehension difficulty are handled by left posterior temporal, left anterior temporal, ventral left frontal, and dorsal left frontal cortices. The functional profiles of these regions likely lie along a spectrum of specificity to generality, including language-specific processing of linguistic representations, more general conflict resolution processes operating over linguistic representations, and processes for handling difficulty in general. These findings suggest that difficulty is not unitary and that there is a role for a variety of linguistic and non-linguistic processes in supporting comprehension.


Assuntos
Compreensão , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Idioma , Linguística , Neuroimagem Funcional , Mapeamento Encefálico
16.
Proc Natl Acad Sci U S A ; 119(49): e2205515119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36442123

RESUMO

Attention describes the ability to selectively process a particular aspect of the environment at the expense of others. Despite the significance of selective processing, the types and scopes of attentional mechanisms in nonprimate species remain underexplored. We trained four carrion crows in Posner spatial cueing tasks using two separate protocols where the attention-capturing cues are shown at different times before target onset at either the same or a different location as the impending target. To probe automatic bottom-up, or exogenous, attention, two naïve crows were tested with a cue that had no predictive value concerning the location of the subsequent target. To examine volitional top-down, or endogenous, attention, the other two crows were tested with the previously learned cues that predicted the impending target location. Comparing the performance for valid (cue and target at same location) and invalid (cue and target at opposing locations) cues in the nonpredictive cue condition showed a transient, mild reaction time advantage signifying exogenous attention. In contrast, there was a strong and long-lasting performance advantage for the valid conditions with predictive cues indicating endogenous attention. Together, these results demonstrate that crows possess two different attention mechanisms (exogenous and endogenous). These findings signify that crows possess a substantial attentional capacity and robust cognitive control over attention allocation.


Assuntos
Corvos , Animais , Sinais (Psicologia) , Aprendizagem , Tempo de Reação
17.
Proc Natl Acad Sci U S A ; 119(5)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35101919

RESUMO

Current models of mental effort in psychology, behavioral economics, and cognitive neuroscience typically suggest that exerting cognitive effort is aversive, and people avoid it whenever possible. The aim of this research was to challenge this view and show that people can learn to value and seek effort intrinsically. Our experiments tested the hypothesis that effort-contingent reward in a working-memory task will induce a preference for more demanding math tasks in a transfer phase, even though participants were aware that they would no longer receive any reward for task performance. In laboratory Experiment 1 (n = 121), we made reward directly contingent on mobilized cognitive effort as assessed via cardiovascular measures (ß-adrenergic sympathetic activity) during the training task. Experiments 2a to 2e (n = 1,457) were conducted online to examine whether the effects of effort-contingent reward on subsequent demand seeking replicate and generalize to community samples. Taken together, the studies yielded reliable evidence that effort-contingent reward increased participants' demand seeking and preference for the exertion of cognitive effort on the transfer task. Our findings provide evidence that people can learn to assign positive value to mental effort. The results challenge currently dominant theories of mental effort and provide evidence and an explanation for the positive effects of environments appreciating effort and individual growth on people's evaluation of effort and their willingness to mobilize effort and approach challenging tasks.


Assuntos
Logro , Cognição/fisiologia , Aprendizagem/fisiologia , Adulto , Tomada de Decisões/fisiologia , Feminino , Humanos , Masculino , Memória de Curto Prazo , Processos Mentais/fisiologia , Motivação/fisiologia , Recompensa , Valores Sociais , Análise e Desempenho de Tarefas , Adulto Jovem
18.
J Neurosci ; 43(7): 1225-1237, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36609452

RESUMO

Cognitive control is the ability to flexibly adapt behavior in a goal-directed manner when habit will not suffice. Control can be separated into distinct forms based on the timescale (present-future) and/or medium (external-internal) over which it operates. Both the frontoparietal network (FPN) and cingulo-opercular network (CON) are engaged during control, but their respective functions and interactions remain unclear. Here, we examined activations in the FPN and CON with fMRI in humans (male and female) during a task that manipulated control across timescales/mediums. The findings show that the CON can be distinguished into the following two separable subnetworks mirroring the FPN: a rostral/ventral subnetwork sensitive to future-oriented control involving internal representations, and a caudal/dorsal subnetwork sensitive to present-oriented control involving external representations. Relative to the FPN, activation in the CON was particularly pronounced during transitions into and out of particular control demands. Moreover, the relationship of each CON subnetwork to behavior was mediated by a respective FPN subnetwork. Such data are consistent with the idea that the CON motivates the FPN, which, in turn, drives behavior. Within the CON, the dorsomedial prefrontal cortex (dmPFC) mediated the relationship between the anterior insula and FPN, suggesting that the dmPFC acts as the crux that links the CON to the FPN. Collectively, these data indicate that parallel CON-FPN subnetworks mediate controlled behaviors at distinct timescales/mediums.SIGNIFICANCE STATEMENT The cingulo-opercular network (CON) and frontoparietal network (FPN) are engaged in diverse, demanding tasks. A functional model describing how areas within these networks can be distinguished, and also interact, would facilitate understanding of how the brain adapts to demanding situations. During a comprehensive control task, fMRI data revealed that the FPN and CON can be fractionated into subnetworks based on control demands that are either externally oriented for use in the present, or control demands that operate internally to guide future behavior. Moreover, we found evidence for a chain of relationships from the CON to FPN to behavior consistent with the idea that the CON drives the FPN to adapt behavior.


Assuntos
Mapeamento Encefálico , Encéfalo , Masculino , Humanos , Feminino , Testes Neuropsicológicos , Encéfalo/fisiologia , Córtex Pré-Frontal , Cognição/fisiologia , Imageamento por Ressonância Magnética
19.
J Neurosci ; 43(15): 2767-2781, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36894317

RESUMO

To better understand how prefrontal networks mediate forms of cognitive control disrupted in schizophrenia, we translated a variant of the AX continuous performance task that measures specific deficits in the human disease to 2 male monkeys and recorded neurons in PFC and parietal cortex during task performance. In the task, contextual information instructed by cue stimuli determines the response required to a subsequent probe stimulus. We found parietal neurons encoding the behavioral context instructed by cues that exhibited nearly identical activity to their prefrontal counterparts (Blackman et al., 2016). This neural population switched their preference for stimuli over the course of the trial depending on whether the stimuli signaled the need to engage cognitive control to override a prepotent response. Cues evoked visual responses that appeared in parietal neurons first, whereas population activity encoding contextual information instructed by cues was stronger and more persistent in PFC. Increasing cognitive control demand biased the representation of contextual information toward the PFC and augmented the temporal correlation of task-defined information encoded by neurons in the two areas. Oscillatory dynamics in local field potentials differed between cortical areas and carried as much information about task conditions as spike rates. We found that, at the single-neuron level, patterns of activity evoked by the task were nearly identical between the two cortical areas. Nonetheless, distinct population dynamics in PFC and parietal cortex were evident. suggesting differential contributions to cognitive control.SIGNIFICANCE STATEMENT We recorded neural activity in PFC and parietal cortex of monkeys performing a task that measures cognitive control deficits in schizophrenia. This allowed us to characterize computations performed by neurons in the two areas to support forms of cognitive control disrupted in the disease. Subpopulations of neurons in the two areas exhibited parallel modulations in firing rate; and as a result, all patterns of task-evoked activity were distributed between PFC and parietal cortex. This included the presence in both cortical areas of neurons reflecting proactive and reactive cognitive control dissociated from stimuli or responses in the task. However, differences in the timing, strength, synchrony, and correlation of information encoded by neural activity were evident, indicating differential contributions to cognitive control.


Assuntos
Sinais (Psicologia) , Córtex Pré-Frontal , Humanos , Masculino , Córtex Pré-Frontal/fisiologia , Lobo Parietal/fisiologia , Neurônios/fisiologia , Cognição/fisiologia
20.
J Neurosci ; 43(45): 7678-7689, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37833065

RESUMO

The ability to adapt behavior after erroneous actions is one of the key aspects of cognitive control. Error commission typically causes people to slow down their subsequent actions [post-error slowing (PES)]. Recent work has challenged the notion that PES reflects adaptive, controlled processing and instead suggests that it is a side effect of the surprising nature of errors. Indeed, human neuroimaging suggests that the brain networks involved in processing errors overlap with those processing error-unrelated surprise, calling into question whether there is a specific system for error processing in the brain at all. In the current study, we used EEG decoding and a novel behavioral paradigm to test whether there are indeed unique, error-specific processes that contribute to PES beyond domain-general surprise. Across two experiments in male and female humans (N = 76), we found that both errors and error-unrelated surprise were followed by slower responses when response-stimulus intervals were short. Furthermore, the early neural processes following error-specific and domain-general surprise showed significant cross-decoding. However, at longer intervals, which provided additional processing time, only errors were still followed by post-trial slowing. Furthermore, this error-specific PES effect was reflected in sustained neural activity that could be decoded from that associated with domain-general surprise, with the strongest contributions found at lateral frontal, occipital, and sensorimotor scalp sites. These findings suggest that errors and surprise initially share common processes, but that after additional processing time, unique, genuinely error-specific processes take over and contribute to behavioral adaptation.SIGNIFICANCE STATEMENT Humans typically slow their actions after errors (PES). Some suggest that PES is a side effect of the unexpected, surprising nature of errors, challenging the notion of a genuine error processing system in the human brain. Here, we used multivariate EEG decoding to identify behavioral and neural processes uniquely related to error processing. Action slowing occurred following both action errors and error-unrelated surprise when time to prepare the next response was short. However, when there was more time to react, only errors were followed by slowing, further reflected in sustained neural activity. This suggests that errors and surprise initially share common processing, but that after additional time, error-specific, adaptive processes take over.


Assuntos
Encéfalo , Desempenho Psicomotor , Humanos , Masculino , Feminino , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Eletroencefalografia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA