Sleep is known to be crucial for human memory, but what about dreams? Previous research has shown that the content of dreams can be manipulated by specific stimuli or tasks prior to sleep, but whether incorporating tasks into dreams influences memory consolidation is less clear. Some studies have shown an association between incorporating memory tasks into dreams and later memory performance, while others show either no effect or weaker effects. Potential reasons for this variation include the targeting of different stages of sleep – including rapid eye moment (REM) and non-REM stages (NREM) – small sample sizes, and the fact that many previous studies do not employ declarative memory tasks, which have been found to benefit more from sleep compared with tasks that target procedural memory.

 

In the current study. Schoch et al. (2023) ask whether dreams are an epiphenomenon of sleep-dependent memory processing or, instead, whether they play a key role in memory consolidation – and if so, whether that role differs for subjective experiences during NREM and REM sleep stages. Using a declarative memory task, a serial awakening paradigm (in which participants are woken and tested during NREM or REM stages), and targeted memory reactivation (TMR), the authors will test two main hypotheses: that incorporating picture categories of a declarative memory task leads to immediate (next morning) and sustained (4 days later) improvement in memory performance (especially for NREM dreams); and second, whether TMR influences the reported content of dreams. The authors also build in a range of control analyses to confirm that the task was incorporated successfully into dreams and that TMR benefited memory performance.

 

The Stage 1 manuscript was evaluated over two rounds of in-depth review, initially at Nature Communications before being transferred to PCI RR for further evaluation (see review history below for details). Based on detailed responses to the reviewers' comments, the recommender judged that the manuscript met the Stage 1 criteria and therefore awarded in-principle acceptance (IPA).
 
URL to the preregistered Stage 1 protocol: https://osf.io/7dwjz

 

Level of bias control achieved: Level 6. No part of the data or evidence that will be used to answer the research question yet exists and no part will be generated until after IPA.
 
List of eligible PCI RR-friendly journals:

 

 

1. Schoch, S. F., Ataei, S., Salvesen, L., Schredl, M., Windt, J., Bernadi, G., Rasch, B., Axmacher, N., & Desler, M. (2023). The relationship of memory consolidation with task incorporations into dreams – A registered report, in principle acceptance of Version 3 by Peer Community in Registered Reports. https://osf.io/7dwjz

Social cognition involves complex processes including empathy, mentalizing, and compassion, which rely on structural connectivity and specifically white matter (WM) integrity. Prior research suggests that deficits in social cognition are linked to deficient structural connectivity, indicating that the latter might be an essential foundation for social cognitive abilities. In the current study, Hansl et al. (2025) explore the relationship between social cognition and white matter (WM) integrity in the brain across different populations, by means of a systematic review and meta-analyses. Using diffusion-weighted imaging data, the authors aim to identify specific WM tracts most associated with social cognition. Meta-analyses of region-of-interest (ROI)-based studies will provide further insights, while meta-regression and subgroup analyses will examine differences across social cognitive constructs, imaging metrics, clinical conditions, and age groups. The findings could clarify global and specific WM contributions to social cognition, guiding future research on brain structure-function relationships in social cognition across various populations.

 

The Stage 1 submission was evaluated by two expert reviewers. After two rounds of revision, the recommender judged that the manuscript met the Stage 1 criteria and awarded in-principle acceptance (IPA).

 

URL to the preregistered Stage 1 protocol: https://osf.io/6n3jy (under temporary private embargo)

 

Level of bias control achieved: Level 2. At least some data/evidence that will be used to answer the research question has been accessed and partially observed by the authors, but the authors certify that they have not yet observed the key variables within the data that will be used to answer the research question and they have taken additional steps to maximise bias control and rigour.

 
List of eligible PCI RR-friendly journals:
 

 

 

1. Hansl, R., Maliske, L. Z., Valk, S. L., & Kanske, P. (2025). Social cognition as a matter of structural brain connections? A systematic review and diffusion weighted imaging meta-analysis. In principle acceptance of Version 3 by Peer Community in Registered Reports. https://osf.io/6n3jy

Both research and public debates around social media use tend to involve a premise of positivity bias, which refers to presenting one’s life in an overly positive light by various different means. This premise contributes to multiple potentially important follow-up hypotheses, such as the fear of missing out and low self-image effects, due to repeated consumption of positive social media content (e.g., Bayer et al. 2020, for a review). The positivity bias of social media use, itself, has received limited research attention. 
 
In the present study, Masciantonio and colleagues (2025) tested positivity bias in the context of three social media platforms: Facebook, Instagram, and X. The experiment involved recruiting participants (n=312) into platform-specific user groups and crafting posts to be shared with friends as well as respective social media audiences. For social media positivity bias to differ from everyday positivity bias, posts in the former should introduce more positive valence in comparison to offline sharing—and if the platforms differ in their encouragement of positivity bias, they should introduce significant between-platform differences in valence.
 
Based on how the participants reported events, the study found no significant differences between everyday and social media positivity bias, but messages posted on Twitter/X had a more negative valence than posts in other social media platforms. The results would be consistent with the implication that people's positive actions in social media simply follow the natural human tendency to present oneself positively to others—a hypothesis that should be investigated in follow-up work. More research attention should also be given to specific design features, which may contribute to platform-specific differences in user habits, as suggested by the distinct valence rate found in relation to Twitter/X.

 

The Stage 2 manuscript was evaluated by three experts (areas: experimental methods, social media, statistics) via in-depth peer review across two rounds, with one reviewer returning to validate analysis code and methdological accuracy on a final round. Based on the authors’ careful responses and revisions, the revised manuscript was judged to meet the Stage 2 criteria and was awarded a positive recommendation. 

 
URL to the preregistered Stage 1 protocol: https://osf.io/9z6hm
 
Level of bias control achieved: Level 6. No part of the data or evidence that was used to answer the research question was generated until after IPA.  
 
List of eligible PCI RR-friendly journals:

 

 

 
1. Bayer, J. B., Triệu, P., & Ellison, N. B. (2020). Social media elements, ecologies, and effects. Annual review of psychology, 71, 471-497. https:// doi.org/10.1146/annurev-psych-010419-050944

 

2. Masciantonio, A., Heiser, N., & Cherbonnier, A. (2025). Unveiling the Positivity Bias on Social Media: A Registered Experimental Study On Facebook, Instagram, And X [Stage 2]. Acceptance of Version 2 by Peer Community in Registered Reports. https://osf.io/s93yu 

The Spatial-Numerical Association of Response Codes (SNARC) effect (Dehaene et al., 1993) is a key phenomenon in numerical cognition. It describes the tendency for individuals to respond faster to smaller numbers with a left-side key and to larger numbers with a right-side key, suggesting a mental mapping of numerical magnitudes onto space. While this effect has been widely replicated, its precise nature remains debated, particularly regarding its task dependency.

 

In this Stage 1 Registered Report, Roth et al. (2025) present a highly powered study that systematically investigates whether the SNARC effect differs in two widely used numerical cognition tasks: magnitude classification (MC) and parity judgment (PJ). In the MC task, participants determine whether a presented number is smaller or larger than a reference value (typically 5). This task explicitly requires magnitude processing, making numerical magnitude directly relevant to the response. In contrast, the PJ task requires participants to judge whether a number is odd or even, a decision that does not explicitly involve numerical magnitude.

 

The authors address a fundamental theoretical question in numerical cognition: while the SNARC effect in PJ is often considered continuous, does it follow a categorical pattern in MC? To investigate this, the study directly compares continuous and categorical representations of the SNARC effect across these two tasks, using Bayesian statistical approaches to determine the best-fitting model. By systematically analysing the SNARC effect in these widely used paradigms, this work aims to refine our understanding of how numerical magnitudes are mapped onto space and whether this mapping depends on task demands. The findings of this study will provide crucial insights into the cognitive mechanisms underlying numerical-spatial associations, highlighting the extent to which task structure shapes the emergence of the SNARC effect.

 

Three expert reviewers provided valuable feedback across multiple rounds of review. Based on ​detailed responses to the reviewers’ and recommender’s comments, the recommender judged that the manuscript met the Stage 1 criteria and therefore awarded in-principle acceptance.​​​

 
URL to the preregistered Stage 1 protocol: https://osf.io/968ad

 

Level of bias control achieved: Level 6. No part of the data or evidence that will be used to answer the research question yet exists and no part will be generated until after IPA.
 
List of eligible PCI RR-friendly journals:

 

 

 

1. Dehaene, S., Bossini, S., & Giraux, P. (1993). The mental representation of parity and number magnitude. Journal of Experimental Psychology: General, 122(3), 371–396. https://doi.org/10.1037/0096-3445.122.3.371

 

2. Roth, L., Cipora, K., Overlander, A. T., Nuerk, H.-C., & Reips, U.-D. (2025). Shape of SNARC: How task-dependent are Spatial-Numerical Associations? A highly powered online experiment. In principle acceptance of Version 3 by Peer Community in Registered Reports. https://osf.io/968ad

‘Pseudoneglect’ is a small, lateralised bias of visuospatial attention towards the left side of space, and is typically observed in healthy adults. Recently, Strauch et al. (2022) reported that bright stimuli presented in the left visual field induced a greater constriction of the pupil (the pupillary light reflex) compared to the same bright stimuli presented in the right visual field. Further, the pupillary restriction bias was positively correlated with a behavioural measure of pseudoneglect (the greyscales task). 

 

In this report, Burns, Grigoraș, Barrie and McIntosh (2025) aimed to replicate and extend the study of Strauch et al. (2022). The extension centred around investigating whether pupillary biases are influenced by recording the pupillary responses from the right or left eye. They found that the eye of recording was indeed important in this context: light presented in the ipsilateral field led to more constriction than in the contralateral field. There was also a small pseudoneglect effect overall, with stronger constriction to light presented to the left vs the right, but no correlation between pupillary restriction bias and the greyscales task. The authors conclude that the split-field paradigm is effective in detecting pseudoneglect, although it is not a particularly sensitive method. This is an important finding, given that these methods could potentially be used to identify subtle lateralised attention impairments in patients with hemispatial neglect, with the added benefit that no manual response is needed to measure pupillary constriction. 

 

The Stage 2 manuscript was reviewed over one round by two reviewers, including an author of the study that was replicated. Based on detailed responses to the reviewers' comments, the recommender judged that the manuscript met the Stage 2 criteria and awarded a positive recommendation.

 

Level of bias control achieved: Level 6. No part of the data or evidence that was used to answer the research question was generated until after IPA.
 
List of eligible PCI-RR-friendly journals:
 

 

1. Strauch, C., Romein, C., Naber, M., Van der Stigchel, S. & Ten Brink, A. F. (2022). The orienting response drives pseudoneglect—Evidence from an objective pupillometric method. Cortex, 151, 259-271. https://doi.org/10.1016/j.cortex.2022.03.006

 

2. Burns, N. E., Grigoraș, V., Barrie, J. & McIntosh, R. D. (2025). Does pupillometry provide a valid measure of spatial attentional bias (pseudoneglect)? [Stage 2] Acceptance of Version 2 by Peer Community in Registered Reports. https://osf.io/qhca4