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Data Repository


This page shows all 160 data sets currently available in our Data repository

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The effect of free-field presentation and processing strategy on a measure of spectro-temporal processing by cochlear-implant listeners
Authors:
ARCHER-BOYD, A., GOEHRING, T., CARLYON, R.
Reference:
Trends in Hearing
Year of publication:
In Press
CBU number:
8555
Abstract:
The STRIPES (Spectro-Temporal Ripple for Investigating Processor EffectivenesS) test is a psychophysical test of spectro-temporal resolution developed for cochlear-implant (CI) listeners. Previously, the test has been strictly controlled to minimize the introduction of extraneous, non-spectro-temporal cues. Here, the effect of relaxing many of those controls was investigated to ascertain the generalizability of the STRIPES test. Pre-emphasis compensation was removed from the STRIPES stimuli, the test was presented over a loudspeaker at a level similar to conversational speech and above the automatic gain control (AGC) threshold of the CI processor, and listeners were tested using the “everyday” setting of their clinical devices. There was no significant difference in STRIPES thresholds measured across conditions for the 10 CI listeners tested. One listener obtained higher (better) thresholds when listening with their clinical processor. An analysis of longitudinal results showed excellent test-retest reliability of STRIPES over multiple listening sessions with similar conditions. Overall, the results show that the STRIPES test is robust to extraneous cues, and that thresholds are reliable over time. It is sufficiently robust for use with different processing strategies, free-field presentation and in non-research settings.
Data available, click to request
Effect of APOE polymorphism on cognition and brain in the CamCAN cohort
Authors:
HENSON, R.N., Suri, S., Knights, E., ROWE, J., KIEVIT, R., Lyall, D.M., Chan, D., Eising, E., Fisher, S.E.
Reference:
Brain and Neuroscience Advances
Year of publication:
In Press
CBU number:
8553
Abstract:
olymorphisms in the Apolipoprotein E (APOE) gene have been associated with individual differences in cognition, brain structure and brain function. For example, the ε4 allele has been associated with cognitive and brain impairment in old age and increased risk of dementia, while the ε2 allele has been claimed to be neuroprotective. According to the “antagonistic pleiotropy” hypothesis, these polymorphisms have different effects across the lifespan, with ε4 for example postulated to confer benefits on cognitive and brain functions earlier in life. In this Stage 2 of the Registered Report https://osf.io/bufc4, we report the results from the cognitive and brain measures in the CamCAN cohort (www.cam-can.org). We investigated the antagonistic pleiotropy hypothesis by testing for allele-by-age interactions in approximately 600 people across the adult lifespan (18-88 years), on six outcome variables related to cognition, brain structure and brain function (namely fluid intelligence, verbal memory, hippocampal gray matter volume, mean diffusion within white matter, and resting-state connectivity measured by both functional magnetic resonance imaging and magnetoencephalography). We found no evidence to support the antagonistic pleiotropy hypothesis. Indeed, Bayes Factors supported the null hypothesis in all cases, except for the (linear) interaction between age and possession of the ε4 allele on fluid intelligence, for which the evidence for faster decline in older ages was ambiguous. Overall, these pre-registered analyses question the antagonistic pleiotropy of APOE polymorphisms, at least in healthy adults.
Data available, click to request
Exploratory factor analysis with structured residuals for brain network data
Authors:
Van Kesteren, E-J. & Kievit, R.
Reference:
Network Neuroscience
Year of publication:
In Press
CBU number:
8544
Abstract:
Dimension reduction is widely used and often necessary to make network analyses and their interpretation tractable by reducing high dimensional data to a small number of underlying variables. Techniques such as Exploratory Factor Analysis (EFA) are used by neuroscientists to reduce measurements from a large number of brain regions to a tractable number of factors. However, dimension reduction often ignores relevant a priori knowledge about the structure of the data. For example, it is well established that the brain is highly symmetric. In this paper, we (a) show the adverse consequences of ignoring a priori structure in factor analysis, (b) propose a technique to accommodate structure in EFA using structured residuals (EFAST), and (c) apply this technique to three large and varied brain imaging network datasets, demonstrating the superior fit and interpretability of our approach. We provide an R software package to enable researchers to apply EFAST to other suitable datasets.
URL:
Data available, click to request
Effect of the Relative Timing between Same-Polarity Pulses on Thresholds and Loudness in Cochlear Implant Users
Authors:
GUERIT, F., Marozeau, J., Bastian, E., CARLYON, R.P.
Reference:
Journal of the Association in Otolaryngology: JARO, 24 Aug 2020
Year of publication:
2020
CBU number:
8543
Abstract:
The effect of the relative timing between pairs of same-polarity monophasic pulses has been studied extensively in single-neuron animal studies, and has revealed fundamental properties of the neurons. For human cochlear-implant listeners, the requirement to use charge-balanced stimulation and the typical use of symmetric, biphasic pulses limits such measures, because currents of opposite polarities interact at the level of the neural membrane. Here, we propose a paradigm to study same-polarity summation of currents, while keeping the stimulation charge-balanced within a short time window. We used pairs of mirrored pseudo-monophasic pulses (a long-low phase followed by a short-high phase for the first pulse, and a short-high phase followed by a long-low phase for the second pulse). We assumed that most of the excitation would stem from the two adjacent short-high phases, which had the same polarity. The inter-pulse interval between the short-high phases was varied from 0 to 345 µs. The inter-pulse interval had a significant effect on the perceived loudness, and this effect was consistent with both passive (membrane-related) and active (ion-channel-related) neuronal mechanisms contrib-uting to facilitation. Furthermore, the effect of interval interacted with the polarity of the pulse pairs. At threshold, there was an effect of polarity, but, surprisingly, no effect of interval nor an interaction between the two factors. We discuss possible peripheral origins of these results.
URL:
Data available, click to request
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, 131, October 2020, Pages 1-16
Year of publication:
2020
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, 30(11), 5915–5929
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


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