Gender (Im)balance in Citation Practices in Cognitive Neuroscience

In the field of neuroscience, despite the fact that the proportion of peer-reviewed publications authored by women has increased in recent decades, the proportion of citations of women-led publications has not seen a commensurate increase: In five broad-scope journals, citations of papers first- and/or last-authored by women have been shown to be fewer than would be expected if gender was not a factor in citation decisions [Dworkin, J. D., Linn, K. A., Teich, E. G., Zurn, P., Shinohara, R. T., & Bassett, D. S. The extent and drivers of gender imbalance in neuroscience reference lists. Nature Neuroscience, 23, 918–926, 2020]. Given the important implications that such underrepresentation may have on the careers of women researchers, it is important to determine whether this same trend is true in subdisciplines of the field, where interventions might be more targeted. Here, we report the results of an extension of the analyses carried out by Dworkin et al. (2020) to citation patterns in the Journal of Cognitive Neuroscience. The results indicate that the underrepresentation of women-led publications in reference sections is also characteristic of papers published in Journal of Cognitive Neuroscience over the past decade. Furthermore, this pattern of citation imbalances is present regardless of author gender, implicating systemic factors. These results contribute to the growing body of evidence that intentional action is needed to address inequities in the way that we carry out and communicate our science.

H-MAGMA, inheriting a shaky statistical foundation, yields excess false positives

The ‘snp-wise mean model’ of Multi-marker Analysis of GenoMic Annotation is often used to perform gene-level testing for association with disease and other phenotypes. This methodology, in turn, forms the foundation for H-MAGMA. Unfortunately, that foundation is unsound, with implications for H-MAGMA results published in Nature Neuroscience regarding genes associated with psychiatric disorders: e.g., only 125 of H-MAGMA’s 275 reported discoveries for autism replicate when the foundation’s flaws are corrected.

Cannabis Research

The International Cannabis Consortium (ICC) was founded in 2013 by Jacqueline Vink, Nathan Gillespie, Karin Verweij and Eske Derks. The largest contribution to the first meta-analysis was made by Prof. Nick Martin. The ICC has published two primary publications, in Translational Psychiatry and Nature Neuroscience, and many secondary publications. The study’s principal investigators will always be grateful for Nick’s contribution to science as they would not have been able to do any of this work without the contributions of Nick and others who collected samples. Nick has made unique contributions to the careers of many junior researchers by supporting their development and growth into senior positions.

Large-scale replication study reveals a limit on probabilistic prediction in language comprehension

Do people routinely pre-activate the meaning and even the phonological form of upcoming words? The most acclaimed evidence for phonological prediction comes from a 2005 Nature Neuroscience publication by DeLong, Urbach and Kutas, who observed a graded modulation of electrical brain potentials (N400) to nouns and preceding articles by the probability that people use a word to continue the sentence fragment (‘cloze’). In our direct replication study spanning 9 laboratories (N=334), pre-registered replication-analyses and exploratory Bayes factor analyses successfully replicated the noun-results but, crucially, not the article-results. Pre-registered single-trial analyses also yielded a statistically significant effect for the nouns but not the articles. Exploratory Bayesian single-trial analyses showed that the article-effect may be non-zero but is likely far smaller than originally reported and too small to observe without very large sample sizes. Our results do not support the view that readers routinely pre-activate the phonological form of predictable words.

A systematic review of sample size and power in leading neuroscience journals

Adequate sample size is key to reproducible research findings: low statistical power can increase the probability that a statistically significant result is a false positive. Journals are increasingly adopting methods to tackle issues of reproducibility, such as by introducing reporting checklists. We conducted a systematic review comparing articles submitted to Nature Neuroscience in the 3 months prior to checklists (n=36) that were subsequently published with articles submitted to Nature Neuroscience in the 3 months immediately after checklists (n=45), along with a comparison journal Neuroscience in this same 3-month period (n=123). We found that although the proportion of studies commenting on sample sizes increased after checklists (22% vs 53%), the proportion reporting formal power calculations decreased (14% vs 9%). Using sample size calculations for 80% power and a significance level of 5%, we found little evidence that sample sizes were adequate to achieve this level of statistical power, even for large effect sizes. Our analysis suggests that reporting checklists may not improve the use and reporting of formal power calculations.

Schwangerschaft beeinflusst Gehirnarchitektur

Hoekzema E et al. Pregnany leads to long-lasting changes in human brain structure. Nature Neuroscience 2017; 20: 287–296 Sexualhormone sind ein wichtiger Regulator der neuronalen Morphologie und Funktion. In Tierexperimenten war eine Reproduktion mit regionalen Veränderungen der Dendriten und der Zellproliferation assoziiert. Standard- und funktionelle MRT belegten nun, dass die dramatische endokrinologische Umstellung in der Schwangerschaft auch beim Menschen mit strukturellen und funktionalen Umbauten verbunden ist. Das Gehirn bereitet gewissermaßen die Mutter-Kind-Beziehung vor.

Limits on prediction in language comprehension: A multi-lab failure to replicate evidence for probabilistic pre-activation of phonology

In current theories of language comprehension, people routinely and implicitly predict upcoming words by pre-activating their meaning, morpho-syntactic features and even their specific phonological form. To date the strongest evidence for this latter form of linguistic prediction comes from a 2005 Nature Neuroscience landmark publication by DeLong, Urbach and Kutas, who observed a graded modulation of article- and noun-elicited electrical brain potentials (N400) by the pre-determined probability that people continue a sentence fragment with that word ('cloze'). In a direct replication study spanning 9 laboratories (N=334), we failed to replicate the crucial article-elicited N400 modulation by cloze, while we successfully replicated the commonly-reported noun-elicited N400 modulation. This pattern of failure and success was observed in a pre-registered replication analysis, a pre-registered single-trial analysis, and in exploratory Bayesian analyses. Our findings do not support a strong prediction view in which people routinely pre-activate the phonological form of upcoming words, and suggest a more limited role for prediction during language comprehension.