How well animals may be able to cope with changes of habitat, specifically with rapid changes and thus novelty they encounter in an environment densely populated by humans, may be influenced by how they respond to novelty in general (Batisteli et al., 2022; Biondi et al., 2024; Castano et al., 2024; Heales et al., 2024). In considering this, it may be important to account for any difference in behavioural responses that animals exhibit when encountering a novel situation alone versus when they are doing so as part of a group.

 

Here, Allaert et al. (2025) tested how neophobia – the fear of unfamiliar objects – is affected by the social context in gulls, birds that are increasingly forced to live in urban environments due to the loss of natural coastlines. In this study, in which they reared herring gulls from egg and tested them taking into account that nestmates are not tested within the same groups, the authors found that the birds were faster to eat and spent more time in the zone of interest when they were tested in a group than when they were tested individually, specifically when a novel object was placed next to the food compared to when that object was a familiar one. The birds were also faster to enter the testing area when tested in a group, but this was not specific to the novel object condition. In addition to these changes in the average responses, the authors also report reduced variance when tested in a group in two of their three measures, namely in the latency to enter the testing area and time spent in the zone of interest.

 

The authors interpret their findings as being mostly in line with the ‘risk-dilution’ hypothesis, which is often considered in terms of predation risk (Krause & Buxton, 2002). They discuss possible reasons why other studies, with different species and different methodological setups, found support for alternative explanations.

 

The Stage 2 report was evaluated by the same two reviewers who had also reviewed the Stage 1 manuscript. In the revision, the authors focused on adding sex as a factor in their statistical models, which was the planned procedure for the statistical analyses in the Stage 1 report, and adding information regarding the problems encountered during testing and how these were handled. This specifically refers to the planned sample size (which the authors planned in the Stage 1 report taking into account both mortality and the fact that some birds would be not herring gulls but lesser black-backed gulls, which can only be established after hatching). However, there was higher than expected mortality, leading to a larger-than-planned overall reduction in sample size. During the study, the authors had contacted the recommender and discussed this issue, and the recommender advised on continuing the study and approved of the planned changes in the Stage 2 report. During the revision process, the authors added more information and also conducted an exploratory analysis, which included all birds, i.e. herring gulls and lesser black-backed gulls. This was suggested by a reviewer and the authors present this exploratory analysis in full in the supplemental material, while the main inferences are presented in the main text. In addition, during the Stage 2 review it became apparent that some minor details regarding the procedure would be useful to be included in the Stage 2 report, which the authors included in the Stage 2 revision. This did not alter the procedure as described in the Stage 1 report, but merely added more clarity to the text.

 

Based on detailed engagement with these points and 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.

 

 

• Peer Community Journal
• PeerJ
• Personality Science
• Royal Society Open Science

 

 

1. Allaert, R., Knoch, S., Braem, S., Debeer, D., Martel, A., Müller, W., Stienen, E., Lens, L., & Verbruggen, F. (2025). Neophobia across social contexts in juvenile Herring gulls [Stage 2]. Acceptance of Version 3 by Peer Community in Registered Reports. https://osf.io/b58ha

 

2. Batisteli, A. F., Pizo, M. A., & Sarmento, H. (2022). Female neophobia predicts the use of buildings as nesting sites in a Neotropical songbird. Animal Behaviour, 183, 151-157. https://doi.org/10.1016/j.anbehav.2021.11.008

 

3. Biondi, L. M., Medina, A., Bonetti, E. A., Paterlini, C. A., & Bó, M. S. (2024). Cognitive flexibility in a generalist raptor: a comparative analysis along an urbanization gradient. Behavioral Ecology, 35, arae025. https://doi.org/10.1093/beheco/arae025

 

4. Castano, M. V., Zumpano, F., Biondi, L. M., & García, G. O. (2024). Does urbanization affect behavioral responses to novel objects in marine birds? The Olrog’s Gull as a case of study. Urban Ecosystems, 27, 427-437. https://doi.org/10.1007/s11252-023-01465-2

 

5. Heales, H. E., Flood, N. J., Oud, M. D., Otter, K. A., & Reudink, M. W. (2024). Exploring differences in neophobia and anti-predator behaviour between urban and rural mountain chickadees. Journal of Urban Ecology, 10, juae01. https://doi.org/10.1093/jue/juae014

 

6. Krause, J. & Ruxton, G. (2002). Living in Groups. Oxford University Press, USA.

​Karakashevska and colleagues (2025) examined the extraretinal representation of visual symmetry presented in a virtual reality environment. Previous research has demonstrated that individuals can detect symmetry when the symmetry is represented on a perspective plane, slanted away from the viewer. In electroencephalography (EEG), perceived symmetry is marked by an Event Related Potential (ERP) called a Sustained Posterior Negativity (SPN). When symmetry is presented on a perspective plane in comparison to front-on (frontoparallel), the SPN is reduced, termed the perspective cost. Here, Karakashevska et al. (2025) determined if presenting symmetry on a perspective plane in a virtual reality (VR) environment reduced the perspective cost with the addition of 3D depth cues. Specifically, participants were requested to detect symmetry or luminance of a stimulus presented in a VR environment whilst wearing an EEG.

 

The authors found no perspective cost during the regularity task when symmetry was presented on a frontoparallel plane versus symmetry on a perspective plane. When participants were performing the luminance task, the authors found no conclusive evidence for the presence or absence of perspective cost. Together these data suggest that when immersed in a virtual reality (VR) environment, critical depth cues are available to overcome perspective cost in the perception of symmetry. 

 

The Stage 2 manuscript was evaluated by two expert reviewers. One of our reviewers reviewed the Stage 1 manuscript, and one reviewer was new. The reviewers agreed that the authors had adhered to their registered Stage 1 manuscript and were convinced by the interpretation of the results. The recommender has determined that the Stage 2 criteria was met and has awarded a positive recommendation. ​

 

URL to the preregistered Stage 1 protocol: https://osf.io/7pnxu
 
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:

 

• Advances in Cognitive Psychology
• Brain and Neuroscience Advances
• Cortex
• Imaging Neuroscience
• NeuroImage: Reports
• Peer Community Journal
• PeerJ
• Psychology of Consciousness: Theory, Research, and Practice
• Royal Society Open Science
• Studia Psychologica

 

 

Karakashevska, E., Batterley, M/, Yuxin, Y., & Makin, A. D. J. (2025). They look virtually the same: extraretinal representation of symmetry in virtual reality [Stage 2]. Acceptance of Version 2 by Peer Community in Registered Reports. https://doi.org/10.31234/osf.io/sfyg6_v2

 

A recent study has reported that the extent of cerebral small vessel disease (cSVD) shows associations with dynamic functional connectivity measures obtained from resting state functional MRI scans (Schlemm et al, 2022). Specifically, when the functional scan was parsed into time spent in discrete brain states, the proportion of time spent in the two most-occupied states was negatively related to a structural indicator of cSVD (volume of white matter hyperintensities of presumed vascular origin). This measure of 'fractional occupancy' was also associated with cognitive impairment as indicated by longer time to complete part B of the Trail Making Test. These findings were based on the analysis of data from 988 participants in the Hamburg City Health Study (HCHS).

 

In the present Registered Report, Schlemm (2023) will test whether these associations can be replicated in an independent sample of participants from the HCHS, not included in the earlier analysis (projected N for new analysis ~1500). In addition to the two main hypothesis tests, an exploratory multiverse analysis will be reported, systematically varying some key parameters of the MRI processing pipeline to provide further information about the robustness of the outcome of the primary hypothesis test. 

 

The Stage 1 plan was refined over two rounds of review by two relevant experts, with additional input from the recommender on the specification of the registered plan. Both reviewers are satisfied that the plan constitutes an appropriate approach to this question, and on the basis of their comments and his own evaluation, the recommender judged that the Stage 1 report meets the criteria for in-principle acceptance.

 

URL to the preregistered Stage 1 protocol: https://osf.io/9yhzc
 
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. Schlemm, E., Frey, B. M., Mayer, C., Petersen, M., Fiehler, J., Hanning, U., Kühn, S., Twerenbold, R., Gallinat, J., Gerloff, C., Thomalla, G. & Cheng, B. (2022). Equalization of brain state occupancy accompanies cognitive impairment in cerebral small vessel disease. Biological Psychiatry, 92, 592-602. https://doi.org/10.1016/j.biopsych.2022.03.019

 

2. Schlemm, E. (2023). Functional MRI brain state occupancy in the presence of cerebral small vessel disease – pre-registration for a replication analysis of the Hamburg City Health Study. In principle acceptance of Version 1.5 by Peer Community in Registered Reports. https://osf.io/9yhzc

In a previous analysis of data from 988 participants in the Hamburg City Health Study (HCHS), Schlemm and colleagues (2022) reported significant associations between the extent of cerebral small vessel disease (cSVD) and dynamic functional connectivity measures from resting state fMRI. Specifically, the volume of white matter hyperintensities of presumed vascular origin, a structural indicator of cSVD, was negatively related to the proportion of time (‘fractional occupancy’) spent in the two most occupied functional brain states. Reduced fractional occupancy was also associated with longer times to complete part B of the Trail Making Test.

 

In the present Registered Report, Ingwersen and colleagues (2023) successfully replicated these associations between structural, functional and cognitive measures in a sample of 1651 HCHS participants not included in the earlier study. An exploratory multiverse analysis found that the associations were generally robust to different brain parcellation and confound regression strategies. These replicable patterns reinforce the idea that cSVD may disrupt the brain’s ability to enter and maintain distinct functional modes, and that these changes in functional dynamics are predictive of cognitive impairment.

 

The Stage 2 manuscript was assessed over one round of in-depth review. The recommender judged that responses to reviewer comments were appropriate, and that the manuscript met the Stage 2 criteria for recommendation.

 

URL to the preregistered Stage 1 protocol: https://osf.io/9yhzc
 
Level of bias control achieved: Level 2. At least some data/evidence that was used to answer the research question had been accessed and partially observed by the authors prior to Stage 1 in-principle acceptance, but the authors certify that they had not yet observed the key variables within the data that were used to answer the research question AND they took additional steps to maximise bias control and rigour.
 
List of eligible PCI RR-friendly journals:
 

 

 

1. Schlemm, E., Frey, B. M., Mayer, C., Petersen, M., Fiehler, J., Hanning, U., Kühn, S., Twerenbold, R., Gallinat, J., Gerloff, C., Thomalla, G. & Cheng, B. (2022). Equalization of brain state occupancy accompanies cognitive impairment in cerebral small vessel disease. Biological Psychiatry, 92, 592-602. https://doi.org/10.1016/j.biopsych.2022.03.019

 

2. Ingwersen, T., Mayer, C., Petersen, M., Frey, B. M., Fiehler, J., Hanning, U., Kühn, S., Gallinat, J., Twerenbold, R., Gerloff, C., Cheng, B., Thomalla, G. & Schlemm, E. (2023). Functional MRI brain state occupancy in the presence of cerebral small vessel disease -- a pre-registered replication analysis of the Hamburg City Health Study. Acceptance of Version 2.01 by Peer Community in Registered Reports. https://github.com/csi-hamburg/HCHS-brain-states-RR/blob/f9d00adbbcf9593d8d191bf5b93912141b80ab1b/manuscript/build/main.pdf

 

Mind-wandering broadly refers to the phenomenon by which a person's thoughts are directed towards internally generated states as opposed to being directed towards those that are task-relevant. It has been proposed that mind-wandering and cognitive control are supported by overlapping neural systems. While neuroimaging work has implicated prefrontal cortex in both mind-wandering and cognitive control, studies testing its causal role using transcranial direct current stimulation (tDCS) have been inconclusive.

 

Here, Rasmussen and colleagues (2025) put to a strict test the question of whether the effects of prefrontal cortex tDCS on mind-wandering are mediated by dopaminergic availablility, which is known to be important for cognitive control. Using noninvasive brain stimuluation (prefrontal cortex tDCS vs sham) and a pharmacological intervention (levodopa vs. placebo), they found that contrary to some previous work, stimulation of prefrontal cortex does not alter mind-wandering. By contrast, in the absence of stimulation, increasing dopamine availability via levodopa reduced the frequency of freely moving thought. Together, these results clarify the degree to which prefrontal cortex tDCS and dopamine play a causal role in mind-wandering

 

The Stage 2 manuscript was evaluated over one round of in-depth review. Based on detailed responses to the reviewers' comments, the recommender judged that the manuscript met the Stage 2 criteria and awarded a positive recommendation.

 

URL to the preregistered Stage 1 protocol: https://osf.io/ujp7e
 
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:
 

• Advances in Cognitive Psychology
• Brain and Neuroscience Advances
• Cortex
• Imaging Neuroscience
• NeuroImage: Reports
• Peer Community Journal
• PeerJ
• Psychology of Consciousness: Theory, Research, and Practice
• Royal Society Open Science
• Studia Psychologica

 

 

Rasmussen, T., Dux, P. E. & Filmer, H. (2025). On the neural substrates of mind wandering and dynamic thought: A drug and brain stimulation study [Stage 2]. Acceptance of Version 2 by Peer Community in Registered Reports. https://doi.org/10.1101/2024.11.02.620526