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1.
2.
Memory ; 31(10): 1320-1339, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37771094

RESUMO

Fast mapping (FM) is a hypothetical, incidental learning process that allows rapid acquisition of new words. Using an implicit reaction time measure in a FM paradigm, Coutanche and Thompson-Schill (Coutanche, M. N., & Thompson-Schill, S. L. (2014). Fast mapping rapidly integrates information into existing memory networks. Journal of Experimental Psychology: General, 143(6), 2296-2303. https://doi.org/10.1037/xge0000020) showed evidence of lexical competition within 10 min of non-words being learned as names of unknown items, consistent with same-day lexicalisation. Here, Experiment 1 was a methodological replication (N = 28/group) that found no evidence of this RT competition effect. Instead, a post-hoc analysis suggested evidence of semantic priming. Experiment 2 (N = 60/group, online study, pre-registered on OSF) tested whether semantic priming remained when making the stimulus set fully counterbalanced. No evidence for either lexical competition nor semantic priming was detected. Experiment 3 (n = 64, online study, pre-registered on OSF) tested whether referent (a)typicality boosted lexical competition (Coutanche, M. N., & Koch, G. E. (2017). Variation across individuals and items determine learning outcomes from fast mapping. Neuropsychologia, 106, 187-193. https://doi.org/10.1016/j.neuropsychologia.2017.09.029), but again no evidence of lexical competition was observed, and Bayes Factors for the data combined across all three experiments supported the hypothesis that there is no effect of lexical competition under FM conditions. These results, together with our previous work, question whether fast mapping exists in healthy adults, at least using this specific FM paradigm.


Assuntos
Aprendizagem , Semântica , Humanos , Adulto , Teorema de Bayes , Tempo de Reação
3.
Brain Struct Funct ; 228(1): 341-352, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35670844

RESUMO

Decades of neuropsychological and neuroimaging evidence have implicated the lateral parietal cortex (LPC) in a myriad of cognitive domains, generating numerous influential theoretical models. However, these theories fail to explain why distinct cognitive activities appear to implicate common neural regions. Here we discuss a unifying model in which the angular gyrus forms part of a wider LPC system with a core underlying neurocomputational function; the multi-sensory buffering of spatio-temporally extended representations. We review the principles derived from computational modelling with neuroimaging task data and functional and structural connectivity measures that underpin the unified neurocomputational framework. We propose that although a variety of cognitive activities might draw on shared underlying machinery, variations in task preference across angular gyrus, and wider LPC, arise from graded changes in the underlying structural connectivity of the region to different input/output information sources. More specifically, we propose two primary axes of organisation: a dorsal-ventral axis and an anterior-posterior axis, with variations in task preference arising from underlying connectivity to different core cognitive networks (e.g. the executive, language, visual, or episodic memory networks).


Assuntos
Imageamento por Ressonância Magnética , Memória Episódica , Imageamento por Ressonância Magnética/métodos , Lobo Parietal , Mapeamento Encefálico , Neuroimagem , Vias Neurais
4.
Psychophysiology ; 60(1): e14152, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35867964

RESUMO

Some aspects of our memory are enhanced by emotion, whereas others can be unaffected or even hindered. Previous studies reported impaired associative memory of emotional content, an effect termed associative "emotional interference". The current study used EEG and an associative recognition paradigm to investigate the cognitive and neural mechanisms associated with this effect. In two experiments, participants studied negative and neutral stimulus-pairs that were either semantically related or unrelated. In Experiment 1 emotions were relevant to the encoding task (valence judgment) whereas in Experiment 2 emotions were irrelevant (familiarity judgment). In a subsequent associative recognition test, EEG was recorded while participants discriminated between intact, rearranged, and new pairs. An associative emotional interference effect was observed in both experiments, but was attenuated for semantically related pairs in Experiment 1, where valence was relevant to the task. Moreover, a modulation of an early associative memory ERP component (300-550 ms) occurred for negative pairs when valence was task-relevant (Experiment 1), but for semantically related pairs when valence was irrelevant (Experiment 2). A later ERP component (550-800 ms) showed a more general pattern, and was observed in all experimental conditions. These results suggest that both valence and semantic relations can act as an organizing principle that promotes associative binding. Their ability to contribute to successful retrieval depends on specific task demands.


Assuntos
Potenciais Evocados , Semântica , Humanos , Potenciais Evocados/fisiologia , Eletroencefalografia , Reconhecimento Psicológico/fisiologia , Emoções
5.
Neuroimage ; 264: 119708, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36280098

RESUMO

Stimulus repetition normally causes reduced neural activity in brain regions that process that stimulus. Some theories claim that this "repetition suppression" reflects local mechanisms such as neuronal fatigue or sharpening within a region, whereas other theories claim that it results from changed connectivity between regions, following changes in synchrony or top-down predictions. In this study, we applied dynamic causal modeling (DCM) on a public fMRI dataset involving repeated presentations of faces and scrambled faces to test whether repetition affected local (self-connections) and/or between-region connectivity in left and right early visual cortex (EVC), occipital face area (OFA) and fusiform face area (FFA). Face "perception" (faces versus scrambled faces) modulated nearly all connections, within and between regions, including direct connections from EVC to FFA, supporting a non-hierarchical view of face processing. Face "recognition" (familiar versus unfamiliar faces) modulated connections between EVC and OFA/FFA, particularly in the left hemisphere. Most importantly, immediate and delayed repetition of stimuli were also best captured by modulations of connections between EVC and OFA/FFA, but not self-connections of OFA/FFA, consistent with synchronization or predictive coding theories, though also possibly reflecting local mechanisms like synaptic depression.


Assuntos
Reconhecimento Facial , Imageamento por Ressonância Magnética , Humanos , Lobo Temporal/fisiologia , Reconhecimento Facial/fisiologia , Mapeamento Encefálico , Reconhecimento Psicológico/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos
6.
Neuroimage ; 258: 119344, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35660461

RESUMO

Early detection of Alzheimer's Disease (AD) is vital to reduce the burden of dementia and for developing effective treatments. Neuroimaging can detect early brain changes, such as hippocampal atrophy in Mild Cognitive Impairment (MCI), a prodromal state of AD. However, selecting the most informative imaging features by machine-learning requires many cases. While large publically-available datasets of people with dementia or prodromal disease exist for Magnetic Resonance Imaging (MRI), comparable datasets are missing for Magnetoencephalography (MEG). MEG offers advantages in its millisecond resolution, revealing physiological changes in brain oscillations or connectivity before structural changes are evident with MRI. We introduce a MEG dataset with 324 individuals: patients with MCI and healthy controls. Their brain activity was recorded while resting with eyes closed, using a 306-channel MEG scanner at one of two sites (Madrid or Cambridge), enabling tests of generalization across sites. A T1-weighted MRI is provided to assist source localisation. The MEG and MRI data are formatted according to international BIDS standards and analysed freely on the DPUK platform (https://portal.dementiasplatform.uk/Apply). Here, we describe this dataset in detail, report some example (benchmark) analyses, and consider its limitations and future directions.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Magnetoencefalografia/métodos , Neuroimagem/métodos
7.
Trends Neurosci ; 45(7): 507-516, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35469691

RESUMO

Recently, cognitive neuroscience has experienced unprecedented growth in the availability of large-scale datasets. These developments hold great methodological and theoretical promise: they allow increased statistical power, the use of nonparametric and generative models, the examination of individual differences, and more. Nevertheless, unlike most 'traditional' cognitive neuroscience research, which uses controlled experimental designs, large-scale projects often collect neuroimaging data not directly related to a particular task (e.g., resting state). This creates a gap between small- and large-scale studies that is not solely due to differences in sample size. Measures obtained with large-scale studies might tap into different neurocognitive mechanisms and thus show little overlap with the mechanisms probed by small-scale studies. In this opinion article, we aim to address this gap and its potential implications for the interpretation of research findings in cognitive neuroscience.


Assuntos
Neurociência Cognitiva , Humanos , Neuroimagem
8.
Neuroimage ; 257: 119056, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35283287

RESUMO

Good scientific practice (GSP) refers to both explicit and implicit rules, recommendations, and guidelines that help scientists to produce work that is of the highest quality at any given time, and to efficiently share that work with the community for further scrutiny or utilization. For experimental research using magneto- and electroencephalography (MEEG), GSP includes specific standards and guidelines for technical competence, which are periodically updated and adapted to new findings. However, GSP also needs to be regularly revisited in a broader light. At the LiveMEEG 2020 conference, a reflection on GSP was fostered that included explicitly documented guidelines and technical advances, but also emphasized intangible GSP: a general awareness of personal, organizational, and societal realities and how they can influence MEEG research. This article provides an extensive report on most of the LiveMEEG contributions and new literature, with the additional aim to synthesize ongoing cultural changes in GSP. It first covers GSP with respect to cognitive biases and logical fallacies, pre-registration as a tool to avoid those and other early pitfalls, and a number of resources to enable collaborative and reproducible research as a general approach to minimize misconceptions. Second, it covers GSP with respect to data acquisition, analysis, reporting, and sharing, including new tools and frameworks to support collaborative work. Finally, GSP is considered in light of ethical implications of MEEG research and the resulting responsibility that scientists have to engage with societal challenges. Considering among other things the benefits of peer review and open access at all stages, the need to coordinate larger international projects, the complexity of MEEG subject matter, and today's prioritization of fairness, privacy, and the environment, we find that current GSP tends to favor collective and cooperative work, for both scientific and for societal reasons.


Assuntos
Eletroencefalografia , Humanos
9.
Neurobiol Aging ; 105: 217-228, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34118787

RESUMO

It is important to maintain cognitive function in old age, yet the neural substrates that support successful cognitive ageing remain unclear. One factor that might be crucial, but has been overlooked due to limitations of previous data and methods, is the ability of brain networks to flexibly reorganize and coordinate over a millisecond time-scale. Magnetoencephalography (MEG) provides such temporal resolution, and can be combined with Hidden Markov Models (HMMs) to characterise transient neural states. We applied HMMs to resting-state MEG data from a large cohort (N=595) of population-based adults (aged 18-88), who also completed a range of cognitive tasks. Using multivariate analysis of neural and cognitive profiles, we found that decreased occurrence of "lower-order" brain networks, coupled with increased occurrence of "higher-order" networks, was associated with both increasing age and decreased fluid intelligence. These results favour theories of age-related reductions in neural efficiency over current theories of age-related functional compensation, and suggest that this shift might reflect a stable property of the ageing brain.


Assuntos
Cognição , Envelhecimento Cognitivo/fisiologia , Rede Nervosa/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Magnetoencefalografia , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Descanso/fisiologia , Adulto Jovem
10.
Front Aging Neurosci ; 13: 746236, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35173599

RESUMO

Sleep quality changes dramatically from young to old age, but its effects on brain dynamics and cognitive functions are not yet fully understood. We tested the hypothesis that a shift in brain networks dynamics relates to sleep quality and cognitive performance across the lifespan. Network dynamics were assessed using Hidden Markov Models (HMMs) in resting-state MEG data from a large cohort of population-based adults (N = 564, aged 18-88). Using multivariate analyses of brain-sleep profiles and brain-cognition profiles, we found an age-related "neural shift," expressed as decreased occurrence of "lower-order" brain networks coupled with increased occurrence of "higher-order" networks. This "neural shift" was associated with both increased sleep dysfunction and decreased fluid intelligence, and this relationship was not explained by age, sex or other covariates. These results establish the link between poor sleep quality, as evident in aging, and a behavior-related shift in neural dynamics.

12.
Behav Brain Sci ; 42: e301, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31896360

RESUMO

The ventral lateral parietal cortex (VLPC) shows robust activation during episodic retrieval, and is involved in content representation, as well as in the evaluation of memory traces. This suggests that the VLPC has a crucial contribution to the quality of recollection and the subjective experience of remembering, and situates it at the intersection of the core and attribution systems.


Assuntos
Memória Episódica , Mapeamento Encefálico , Humanos , Transtornos da Memória , Rememoração Mental , Lobo Parietal
13.
eNeuro ; 6(5)2019.
Artigo em Inglês | MEDLINE | ID: mdl-31451605

RESUMO

How do we recall vivid details from our past based only on sparse cues? Research suggests that the phenomenological reinstatement of past experiences is accompanied by neural reinstatement of the original percept. This process critically depends on the medial temporal lobe (MTL). Within the MTL, perirhinal cortex (PRC) and parahippocampal cortex (PHC) are thought to support encoding and recall of objects and scenes, respectively, with the hippocampus (HC) serving as a content-independent hub. If the fidelity of recall indeed arises from neural reinstatement of perceptual activity, then successful recall should preferentially draw upon those neural populations within content-sensitive MTL cortex that are tuned to the same content during perception. We tested this hypothesis by having eighteen human participants undergo functional MRI (fMRI) while they encoded and recalled objects and scenes paired with words. Critically, recall was cued with the words only. While HC distinguished successful from unsuccessful recall of both objects and scenes, PRC and PHC were preferentially engaged during successful versus unsuccessful object and scene recall, respectively. Importantly, within PRC and PHC, this content-sensitive recall was predicted by content tuning during perception: Across PRC voxels, we observed a positive relationship between object tuning during perception and successful object recall, while across PHC voxels, we observed a positive relationship between scene tuning during perception and successful scene recall. Our results thus highlight content-based roles of MTL cortical regions for episodic memory and reveal a direct mapping between content-specific tuning during perception and successful recall.


Assuntos
Imageamento por Ressonância Magnética/métodos , Rememoração Mental/fisiologia , Córtex Perirrinal/diagnóstico por imagem , Córtex Perirrinal/fisiologia , Estimulação Luminosa/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Distribuição Aleatória , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Adulto Jovem
14.
Psychophysiology ; 56(11): e13446, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31369155

RESUMO

Although it is often assumed that memory of episodic associations requires recollection, it has been suggested that, when stimuli are experienced as a unit, earlier memory processes might contribute to their subsequent associative recognition. We investigated the effects of associative relations and perceptual domain during episodic encoding on the ability to utilize early memory processes to retrieve associative information. During the study phase, participants encoded compound and noncompound words pairs, presented either to the same sensory modality (visual presentation) or to different sensory modalities (audiovisual presentation). At the test phase, they discriminated between old, rearranged, and new pairs while ERPs were recorded. In an early ERP component, differences related to associative memory emerged only for compounds, regardless of their encoding modality. These findings indicate that episodic retrieval of compound words can be supported by early-onset recognition processes regardless of whether both words were presented to the same or different sensory modalities, and suggests that unitization can operate at an abstract level, across a broad range of materials.


Assuntos
Associação , Córtex Cerebral/fisiologia , Potenciais Evocados/fisiologia , Memória Episódica , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Percepção da Fala/fisiologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto Jovem
15.
J Neurosci ; 39(22): 4365-4374, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-30902869

RESUMO

Much evidence suggests that the angular gyrus (AnG) is involved in episodic memory, but its precise role has yet to be determined. We examined two possible accounts within the same experimental paradigm: the "cortical binding of relational activity" (CoBRA) account (Shimamura, 2011), which suggests that the AnG acts as a convergence zone that binds multimodal episodic features, and the subjectivity account (Yazar et al., 2012), which implicates AnG involvement in subjective mnemonic experience (such as vividness or confidence). fMRI was used during both encoding and retrieval of paired associates. During study, female and male human participants memorized picture-pairs of common objects (in the unimodal task) or of an object-picture and an environmental sound (in the crossmodal task). At test, they performed a cued-recall task and further indicated the vividness of their memory. During retrieval, BOLD activation in the AnG was greatest for vividly remembered associates, consistent with the subjectivity account. During encoding, the same effect of vividness was found, but this was further modulated by task: greater activations were associated with subsequent recall in the crossmodal than the unimodal task. Therefore, encoding data suggest an additional role to the AnG in crossmodal integration, consistent with its role at retrieval proposed by CoBRA. These results resolve some of the puzzles in the literature and indicate that the AnG can play different roles during encoding and retrieval as determined by the cognitive demands posed by different mnemonic tasks.SIGNIFICANCE STATEMENT We offer new insights into the multiplicity of processes that are associated with angular gyrus (AnG) activation during encoding and retrieval of newly formed memories. We used fMRI while human participants learned and subsequently recalled pairs of objects presented to the same sensory modality or to different modalities. We were able to show that the AnG is involved when vivid memories are created and retrieved, as well as when encoded information is integrated across different sensory modalities. These findings provide novel evidence for the contribution of the AnG to our subjective experience of remembering alongside its role in integrative processes that promote subsequent memory.


Assuntos
Memória Episódica , Lobo Parietal/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
16.
J Exp Psychol Gen ; 148(2): 325-341, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30394766

RESUMO

Events that conform to our expectations, that is, are congruent with our world knowledge or schemas, are better remembered than unrelated events. Yet events that conflict with schemas can also be remembered better. We examined this apparent paradox in 4 experiments, in which schemas were established by training ordinal relationships between randomly paired objects, whereas event memory was tested for the number of objects on each trial. Better memory was found for both congruent and incongruent trials, relative to unrelated trials, producing memory performance that was a "U-shaped" function of congruency. The congruency advantage but not incongruency advantage was mediated by postencoding processes, whereas the incongruency advantage, but not congruency advantage, emerged even if the information probed by the memory test was irrelevant to the schema. Schemas therefore augment event memory in multiple ways, depending on the match between novel and existing information. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Aprendizagem por Associação/fisiologia , Rememoração Mental/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Adulto , Feminino , Humanos , Conhecimento , Masculino , Adulto Jovem
17.
Mem Cognit ; 46(7): 1023-1040, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29744769

RESUMO

Unitization refers to the creation of a new unit from previously distinct items. The concept of unitization has been used to explain how novel pairings between items can be remembered without requiring recollection, by virtue of new, item-like representations that enable familiarity-based retrieval. We tested an alternative account of unitization - a schema account - which suggests that associations between items can be rapidly assimilated into a schema. We used a common operationalization of "unitization" as the difference between two unrelated words being linked by a definition, relative to two words being linked by a sentence, during an initial study phase. During the following relearning phase, a studied word was re-paired with a new word, either related or unrelated to the original associate from study. In a final test phase, memory for the relearned associations was tested. We hypothesized that, if unitized representations act like schemas, then we would observe some generalization to related words, such that memory would be better in the definition than sentence condition for related words, but not for unrelated words. Contrary to the schema hypothesis, evidence favored the null hypothesis of no difference between definition and sentence conditions for related words (Experiment 1), even when each cue was associated with multiple associates, indicating that the associations can be generalized (Experiment 2), or when the schematic information was explicitly re-activated during Relearning (Experiment 3). These results suggest that unitized associations do not generalize to accommodate new information, and therefore provide evidence against the schema account.


Assuntos
Aprendizagem por Associação/fisiologia , Generalização Psicológica/fisiologia , Rememoração Mental/fisiologia , Reconhecimento Psicológico/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
18.
Neurobiol Learn Mem ; 150: 75-83, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29522808

RESUMO

In studies of behavioral reconsolidation interference, reactivation of a consolidated memory using some form of reminder is followed by the presentation of new information that can cause interference with that memory. Under these conditions, the interference not only impairs retrieval by indirect processes such as cue interference, but supposedly disrupts the original memory trace directly. Almost all studies of behavioral reconsolidation interference in episodic memory in humans have employed between-subjects paradigms, and deduced reminder effects from intrusion errors. Such studies might introduce confounds arising, for example, from differences in retrieval strategies engendered by the pre-test treatments. We therefore set out to examine whether behavioral reconsolidation interference in episodic memory might be demonstrated within-subjects and by direct memory strength rather than intrusion errors. In three separate experiments, we attempted to disrupt reconsolidation of episodic object-picture memory using a reminder + retroactive interference manipulation. We applied the manipulation over three consecutive days, using a forced-choice recognition test without intrusions from interfering learning, keeping all other study and test parameters constant. No effects of reminder-potentiated interference were observed for measures of accuracy, response times, subjective expressions of recollection, or levels of confidence, as substantiated by Bayesian analyses. These results highlight the difficulty of observing clear behavioral reconsolidation interference effects within-subjects in human episodic memory, and provide some indications of what might be boundary conditions for its demonstration.


Assuntos
Consolidação da Memória/fisiologia , Memória Episódica , Rememoração Mental/fisiologia , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
19.
Trends Cogn Sci ; 22(4): 271-274, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29482978

RESUMO

Academic conferences are among the most prolific scientific activities, yet the current abstract submission and review process has serious limitations. We propose a revised process that would address these limitations, achieve some of the aims of Open Science, and stimulate discussion throughout the entire lifecycle of the scientific work.


Assuntos
Neurociência Cognitiva , Congressos como Assunto , Revisão da Pesquisa por Pares , Neurociência Cognitiva/normas , Congressos como Assunto/normas , Humanos , Revisão da Pesquisa por Pares/normas
20.
Artigo em Inglês | MEDLINE | ID: mdl-28756745

RESUMO

Memory for episodic associations declines in aging, ostensibly due to decreased recollection abilities. Accordingly, associative unitization - the encoding of associated items as one integrated entity - may potentially attenuate age-related associative deficits by enabling familiarity-based retrieval, which is relatively preserved in aging. To test this hypothesis, we induced bottom-up unitization by manipulating semantic relatedness between memoranda. Twenty-four young and 24 older adults studied pairs of object pictures that were either semantically related or unrelated. Participants subsequently discriminated between intact, recombined and new pairs. We found that semantic relatedness increased the contributions of both familiarity and recollection in young adults, but did not improve older adults' performance. Instead, they showed associative deficits, driven by increased recollection-based false recognition. This may reflect a "misrecollection" phenomenon, in which older adults make more false alarms to recombined pairs with particularly high confidence, due to poorer retrieval monitoring regarding semantically-related associative probes.


Assuntos
Associação , Envelhecimento Cognitivo , Memória , Semântica , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento Cognitivo/psicologia , Discriminação Psicológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Visual de Modelos , Adulto Jovem
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