Neuroscience

Evaluation Summary:

This paper will be of interest to researchers in the fields of biomechanics, movement control, and decision making. It presents a novel mechanistic model of metabolic cost that includes a cost for rate of muscle force production explains metabolic cost better than current models. They next demonstrate how this metabolic model can improve our understanding of movement control by revealing an energetic basis for smooth movements.

This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #2 agreed to share their name with the authors.

Evaluation Summary:

This paper is a milestone towards understanding the formation and representation of visual object structure in the brain. It shows that in the pivotal area V4, border ownership selectivity emerges in the deep layers earlier than in the granular layers which receive the input from V1/V2, indicating that border ownership is not inherited from the input, but computed by deep-layer neurons using visual context information possibly provided through horizontal connections, cortico-cortical feedback or thalamic input. They further report that the preferred side of border ownership across layers is similar, i.e. it is organized in a columnar fashion. The study is elegantly done, with the outstanding questions clearly laid out and the results presented in a clear and informative fashion.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #2 and Reviewer #3 agreed to share their names with the authors.)

Evaluation Summary:

There has been a longstanding interest in developing normative models of how humans handle latent information in stochastic and volatile environments. This study examines recurrent neural network models trained on sequence-prediction tasks analogous to those used in human cognitive studies. The results demonstrate that such models lead to highly accurate predictions for challenging sequences in which the statistics are non-stationary and change at random times. This is a novel and remarkable result that opens up new avenues for cognitive modelling.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1 and Reviewer #2 agreed to share their names with the authors.)

Evaluation Summary:

In this study, Hahn et al. taught crows to perform a working memory task designed to mimic traditional monkey tasks. Using a combination of behavior and electrophysiology, the authors convincingly show that the neural mechanisms that limit working memory capacity in mammals and primates also limit working memory capacity in crows. What makes this finding particularly interesting is that the architecture of the avian brain is dramatically different than the architecture of the primate brain. Thus, two dramatically different architectures give rise to the same behavioral functions and neural computations. Such cross-species comparisons are fundamental to understanding the computational constraints that are placed on cognition and the brain.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #3 agreed to share their name with the authors.)

Evaluation Summary:

This study uses intracranial EEG to explore links between broad-band gamma oscillations and mood, and their impact on decisions. While the results are potentially interesting, additional details and analyses are necessary to show that results are not driven by confounds. In addition, there is about a major concern that statistics are performed across electrodes instead of across subjects.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)

Evaluation Summary:

This study provides a novel mouse model for the study of the central respiratory chemoreceptor circuit and, therefore, of interest for the respiratory physiology community. Nonetheless, in its present form, this work still lacks more physiological, developmental, and anatomical characterizations to place this study in a broader context and gain new insights into the physiology of respiratory chemoreflexes.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1 and Reviewer #3 agreed to share their names with the authors.)

Evaluation Summary:

This study investigates evolutionary changes in ligand preference that occur in an olfactory receptor (IR75a) across the Drosophila phylogeny. The authors find that IR75a displays different odor preferences, for acetic acid or butyric acid, across Drosophila species, and link odor preference to particular protein mutations in the receptor. Reconstruction of a putative ancestral IR75a revises the timeline for IR75a evolution, and structural modeling suggests how mutations alter odor preference.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)

Evaluation Summary:

The manuscript used a naturalistic task where mice were fear conditioned to a context using a live predator (cat) and a variety of behavioural measures including freezing, risk assessment, and exploration. The identification of anterior cingulate cortex and its input and outputs in contextual fear acquisition and expression to predator threat is an important contribution to our understanding of neural mechanism related to fear processing. The paper will be of interest to researchers interested in using naturalistic threats in the lab, and to a more broad audience interested in learning and the related fear circuits.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #3 agreed to share their name with the authors.)

Evaluation Summary:

This paper introduces a new method to measure motivation to engage with familiar or unfamiliar individuals in prairie voles, a widely used animal model system for studying social relationships. The authors show that female prairie voles will work harder to access both familiar pair-bonded males or familiar females. In contrast, male prairie voles will work to access both pair-bonded females as well as unfamiliar females. These results cast a new light on decades of work based partner-preference tests that assess pair bonds that do not assess the role of motivation.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #3 agreed to share their name with the authors.)

Evaluation Summary:

A combination of methods. including a new method for tagging genes, demonstrates that the chemosensory co-receptors of Drosophila melanogaster (Orco, IR8a, IR25a, IR76b) are expressed widely and highly overlapping. These findings challenge a long-standing dogma in the field and suggest that different types of receptors, i.e. olfactory and ionotropic receptors, can be co-expressed in the same chemosensory neuron. Moreover, optogenetics and single sensillum recordings provide evidence that IR25a co-receptor might modulate the activity of typical Orco-dependent olfactory sensory neurons.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)