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Data Repository


This page shows all 155 data sets currently available in our Data repository

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Hierarchical representation of multi-step tasks in multiple-demand and default mode networks
Authors:
WEN, T., DUNCAN, J.D., MITCHELL, D.
Reference:
The Journal of Neuroscience
Year of publication:
-
CBU number:
8541
Abstract:
Task episodes consist of sequences of steps that are performed to achieve a goal. We used fMRI to examine neural representation of task identity, component items, and sequential position, focusing on two major cortical systems – the multiple-demand (MD) and default mode networks (DMN). Human participants (20 male, 22 female) learned six tasks each consisting of four steps. Inside the scanner, participants were cued which task to perform and then sequentially identified the target item of each step in the correct order. Univariate time-course analyses indicated that intra-episode progress was tracked by a tonically increasing global response, plus an increasing phasic step response specific to MD regions. Inter-episode boundaries evoked a widespread response at episode onset, plus a marked offset response specific to DMN regions. Representational similarity analysis was used to examine representation of task identity and component steps. Both networks represented the content and position of individual steps, however the DMN preferentially represented task identity while the MD network preferentially represented step-level information. Thus, although both MD and DMN networks are sensitive to step-level and episode-level information in the context of hierarchical task performance, they exhibit dissociable profiles in terms of both temporal dynamics and representational content. The results suggest collaboration of multiple brain regions in control of multi-step behavior, with MD regions particularly involved in processing the detail of individual steps, and DMN adding representation of broad task context.
Data available, click to request
Activity in the Fronto-Parietal Multiple-Demand Network is Robustly Associated with Individual Differences in Working Memory and Fluid Intelligence
Authors:
ASSEM, M., Asher Blank, I., Mineroff, Z. Ademoglu,A., Fedorenko, E.
Reference:
Cortex
Year of publication:
In Press
CBU number:
8535
Abstract:
Numerous brain lesion and fMRI studies have linked individual differences in executive abilities and fluid intelligence to brain regions of the fronto-parietal “multiple-demand” (MD) network. Yet, fMRI studies have yielded conflicting evidence as to whether better executive abilities are associated with stronger or weaker MD activations and whether this relationship is restricted to the MD network. Here, in a large-sample (n=216) fMRI investigation, we found that stronger activity in MD regions – functionally defined in individual participants – was robustly associated with more accurate and faster responses on a spatial working memory task performed in the scanner, as well as fluid intelligence measured independently (n=114). In line with some prior claims about a relationship between language and fluid intelligence, we also found a weak association between activity in the brain regions of the left fronto-temporal language network during an independent passive reading task, and performance on the working memory task. However, controlling for the level of MD activity abolished this relationship, whereas the MD activity-behavior association remained highly reliable after controlling for the level of activity in the language network. Finally, we demonstrate how unreliable MD activity measures, coupled with small sample sizes, could falsely lead to the opposite, negative, association that has been reported in some prior studies. Taken together, these results demonstrate that a core component of individual differences variance in executive abilities and fluid intelligence is selectively and robustly positively associated with the level of activity in the MD network, a result that aligns well with lesion studies.
URL:
Data available, click to request
Multi-dimensional connectivity: a conceptual and mathematical review.
Authors:
Basti, A., Nili, H., HAUK, O., Marzetti, L., HENSON, R.N.
Reference:
NeuroImage, 1 November 2020, 117140
Year of publication:
2020
CBU number:
8534
Abstract:
The estimation of functional connectivity between regions of the brain, for example based on statistical dependencies between the time series of activity in each region, has become increasingly important in neuroimaging. Typically, multiple time series (e.g. from each voxel in fMRI data) are first reduced to a single time series that summarises the activity in a region of interest, e.g. by averaging across voxels or by taking the first principal component; an approach we call one-dimensional connectivity. However, this summary approach ignores potential multi-dimensional connectivity between two regions, and a number of recent methods have been proposed to capture such complex dependencies. Here we review the most common multi-dimensional connectivity methods, from an intuitive perspective, from a formal (mathematical) point of view, and through a number of simulated and real (fMRI and MEG) data examples that illustrate the strengths and weaknesses of each method. The paper is accompanied with both functions and scripts, which implement each method and reproduce all the examples.
URL:
Data available, click to request
The functional convergence and heterogeneity of social, episodic, and self-referential thought in the default mode network
Authors:
WEN, T., MITCHELL, D.J., DUNCAN, J.
Reference:
Cerebral Cortex
Year of publication:
2020
CBU number:
8525
Abstract:
The default mode network (DMN) is engaged in a variety of cognitive settings, including social, semantic, temporal, spatial, and self-related tasks. Andrews-Hanna et al. (2010, 2012) proposed that the DMN consists of three distinct functional-anatomical subsystems – a dorsal medial prefrontal cortex (dMPFC) subsystem that supports social cognition; a medial temporal lobe (MTL) subsystem that contributes to memory-based scene construction; and a set of midline core hubs that are especially involved in processing self-referential information. We examined activity in the DMN subsystems during six different tasks: (1) theory of mind, (2) moral dilemmas, (3) autobiographical memory, (4) spatial navigation, (5) self/other adjective judgement, and (6) a rest condition. At a broad level, we observed similar whole-brain activity maps for the six contrasts, and some response to every contrast in each of the three subsystems. In more detail, both univariate analysis and multivariate activity patterns showed partial functional separation, especially between dMPFC and MTL subsystems, though with less support for common activity across the midline core. Integrating social, spatial, self-related, and other aspects of a cognitive situation or episode, multiple components of the DMN may work closely together to provide the broad context for current mental activity.
URL:
Data available, click to request
Noradrenergic-dependent functions are associated with age-related locus coeruleus signal intensity differences
Authors:
Liu, K.Y., KIEVIT, R.A., Tsvetanov, K.A., Betts, M.J., Düzel, E., Rowe, J.B., Cam-CAN*, Howard, R. & Hämmerer, D.
Reference:
Nature Communications, 11(1):1712
Year of publication:
2020
CBU number:
8510
Abstract:
The locus coeruleus (LC), the origin of noradrenergic modulation of cognitive and behavioral function, may play an important role healthy ageing and in neurodegenerative conditions. We investigated the functional significance of age-related differences in mean normalized LC signal intensity values (LC-CR) in magnetization-transfer (MT) images from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) cohort - an open-access, population-based dataset. Using structural equation modelling, we tested the pre-registered hypothesis that putatively noradrenergic (NA)-dependent functions would be more strongly associated with LC-CR in older versus younger adults. A unidimensional model (within which LC-CR related to a single factor representing all cognitive and behavioral measures) was a better fit with the data than the a priori two-factor model (within which LC-CR related to separate NAdependent and NA-independent factors). Our findings support the concept that age-related reduction of LC structural integrity is associated with impaired cognitive and behavioral function.
URL:
Data available, click to request
Contributions of working memory and inhibition to cognitive flexibility in Nigerian adolescents
Authors:
NWEZE, T., Nwani, W.
Reference:
Developmental Neuropsychology, 45(3), 118-128
Year of publication:
2020
CBU number:
8506
Abstract:
This study used a novel approach that combined the latency and accuracy scores to examine the relative involvement of inhibition and working memory in two measures of cognitive flexibility – mixing cost and switch cost in 110 Nigerian adolescents. Results showed that inhibition was significantly associated with switch cost. On the other hand, working memory was negatively associated with mixing cost. These findings support the assumptions that cognitive flexibility skills are dependent on inputs from inhibition and working memory processes. Inhibition is involved in the deactivation of irrelevant stimuli during switching trials while working memory is essential to maintain the current rule in sets that require no shifting. Pre-Print link: https://psyarxiv.com/m2zsg/
URL:
Data available, click to request
A Domain-General Cognitive Core Defined in Multimodally Parcellated Human Cortex
Authors:
ASSEM, M., Glasser, M.F., Van Essen, D.C., DUNCAN, J.D.
Reference:
Cerebral Cortex
Year of publication:
In Press
CBU number:
8505
Abstract:
Numerous brain imaging studies identified a domain-general or “multiple-demand” (MD) activation pattern accompanying many tasks and may play a core role in cognitive control. Though this finding is well established, the limited spatial localization provided by traditional imaging methods precluded a consensus regarding the precise anatomy, functional differentiation, and connectivity of the MD system. To address these limitations, we used data from 449 subjects from the Human Connectome Project, with the cortex of each individual parcellated using neurobiologically grounded multimodal MRI features. The conjunction of three cognitive contrasts reveals a core of 10 widely distributed MD parcels per hemisphere that are most strongly activated and functionally interconnected, surrounded by a penumbra of 17 additional areas. Outside cerebral cortex, MD activation is most prominent in the caudate and cerebellum. Comparison with canonical resting-state networks shows MD regions concentrated in the fronto-parietal network but also engaging three other networks. MD activations show modest relative task preferences accompanying strong co-recruitment. With distributed anatomical organization, mosaic functional preferences, and strong interconnectivity, we suggest MD regions are well positioned to integrate and assemble the diverse components of cognitive operations. Our precise delineation of MD regions provides a basis for refined analyses of their functions.
URL:
Data available, click to request
Evaluating the granularity and statistical structure of lesions and behaviour in post-stroke aphasia
Authors:
ZHAO, Y., HALAI, A., LAMBON RALPH, M.A.
Reference:
Brain Communications
Year of publication:
In Press
CBU number:
8501
Abstract:
The pursuit of relating the location of neural damage to the pattern of acquired language and general cognitive deficits post-stroke stems back to 19th century behavioural neurology. Whilst spatial specificity has improved dramatically over time, from the large areas of damage specified by post-mortem investigation to the millimetre precision of modern MRI, there is an underlying issue that is rarely addressed, which relates to the fact that damage to a given area of the brain is not random but constrained by the brain’s vasculature. Accordingly, the aim of this study was to uncover the statistical structure underlying the lesion profile in chronic aphasia post-stroke. By applying varimax-rotated principal component analysis to the lesions of 70 patients with chronic post-stroke aphasia, we identified 17 interpretable clusters, largely reflecting the vascular supply of middle cerebral artery sub-branches and other sources of individual variation in vascular supply as shown in classical angiography studies. This vascular parcellation produced smaller displacement error in simulated lesion-symptom analysis compared with individual voxels and Brodmann regions. A second principal component analysis of the patients’ detailed neuropsychological data revealed a four factor solution reflecting phonological, semantic, executive-demand and speech fluency abilities. As a preliminary exploration, stepwise regression was used to relate behavioural factor scores to the lesion principal components. Phonological ability was related to two components, which covered the posterior temporal region including the posterior segment of the arcuate fasciculus, and the inferior frontal gyrus. Three components were linked to semantic ability and were located in the white matter underlying the anterior temporal lobe, the supramarginal gyrus and angular gyrus. Executive-demand related to two components covering the dorsal edge of the middle cerebral artery territory, while speech fluency was linked to two components that were located in the middle frontal gyrus, precentral gyrus, and subcortical regions (putamen and thalamus). Future studies can explore in formal terms the utility of these PCA-derived lesion components for relating post-stroke lesions and symptoms. Preprint link: http://europepmc.org/article/PPR/PPR98746
Data available, click to request
Evidence for prereg posters as a platform for preregistration
Authors:
Brouwers, K., Cooke, A., Chambers, C.D., HENSON, R.N.A., & TIBON, R.
Reference:
Nature Human Behaviour, 27 Apr 2020,
Year of publication:
2020
CBU number:
8499
Abstract:
Prereg posters are conference posters that present planned scientific projects. We provide preliminary evidence for their value in receiving constructive feedback, promoting open science, and supporting early career researchers. Preprint link: https://www.biorxiv.org/content/10.1101/833640v2
Data available, click to request
Working for the future: Parentally deprived Nigerian Children have enhanced working memory ability
Authors:
NWEZE, T., Nwoke, M.B., Nwufo, J.I., Aniekwu, R.I., Lange,F.
Reference:
Journal of Child Psychology and Psychiatry
Year of publication:
In Press
CBU number:
8482
Abstract:
Background: The dominant view based on the deficit model of developmental psychopathology is that early adverse rearing impairs cognition. In contrast, an emerging evolutionary-developmental model argues that individuals exposed to early life stress may have improved cognitive abilities that are adapted to harsh environments. We set out to test this hypothesis by examining cognitive functions in parentally deprived children in Nigeria. Methods: Cognitive performance was compared between 53 deprived children who currently live in institutional homes and foster families and 51 non-deprived control participants. We used a multifaceted neurocognitive test battery for the assessment of inhibition, set shifting, and working memory. Results: Results showed that the deprived and non-deprived group did not significantly differ in their performance on set-shifting and inhibition tasks. Conversely, the deprived group performed significantly better than the non-deprived group in the working memory task. Discussion: We interpret the enhanced working memory ability of the deprived group as a correlate of its ecological relevance. In Nigeria, underprivileged children may need to rely to a larger extent on working memory abilities to attain success through academic work. This study provides further evidence that exposure to early adversity does not necessarily impair cognitive functions but can even enhance it under some conditions and in some domains.
URL:
Data available, click to request


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