Biology subjects

Vogels, R.

Publications and source records attributed to Vogels, R..

9 recordsLinked to original sources

bioRxiv2026

Local Motion Is Sufficient for Human Body Movement Perception in High-Level Visual Cortex

Perceiving the movements of other living organisms is a fundamental ability across species. Although several cortical regions are selective for static body features, it is unclear whether these areas also encode motion cues independently of body shapes. Here, we isolated optical flow patterns from naturalistic body movements using synthesized videos that eliminate explicit body shape information. Behavioral results suggest that participants successfully recognized walking directions from the shape-free flow motion stimuli. Using ultra-high field fMRI, we found that three body-motion-related areas, fusiform gyrus (FG), lateral occipitotemporal cortex (LOTC), and posterior superior temporal sulcus (pSTS), were sensitive to both the amount and the spatiotemporal structure of flow motion. Critically, the flow motion effects were significantly correlated to voxel-wise body motion selectivity in FG and LOTC, but not to body shape selectivity in any of the ROIs. These findings identify flow motion as a distinct and behaviorally sufficient cue for body perception, which could dissociate the neural mechanism underlying motion and shape encoding in FG and LOTC.

neuroscience↗

bioRxiv2024

Integration of head and body orientations in the macaque superior temporal sulcus is specific to upright bodies

The neural processing of faces and bodies is often studied separately, despite their natural integration in perception. Unlike prior research on the neural selectivity for either head or body orientation, we investigated their interaction in macaque superior temporal sulcus (STS) using a monkey avatar with diverse head-body orientation angles. STS neurons showed selectivity for specific combinations of head-body orientations. Anterior STS (aSTS) neurons enabled more reliable decoding of head-body configuration angles compared to middle STS neurons. Decoding accuracy in aSTS was lowest for head-body angle pairs differing only in sign (e.g. head-body orientation difference of {+/-}90{degrees} relative to the anatomical midline), and highest for aligned (0{degrees}) head-body orientations versus those with maximum angular difference. Inverted bodies showed diminished decoding of head-body orientation angle compared to upright bodies. These findings show that aSTS integrates head and body orientation cues, revealing configuration-specific neural mechanisms, and advance our understanding of social perception.

neuroscience↗

bioRxiv2024

MacAction: Realistic 3D macaque body animation based on multi-camera markerless motion capture

Social interaction is crucial for survival in primates. For the study of social vision in monkeys, highly controllable macaque face avatars have recently been developed, while body avatars with realistic motion do not yet exist. Addressing this gap, we developed a pipeline for three-dimensional motion tracking based on synchronized multi-view video recordings, achieving sufficient accuracy for life-like full-body animation. By exploiting data-driven pose estimation models, we track the complete time course of individual actions using a minimal set of hand-labeled keyframes. Our approach tracks single actions more accurately than existing pose estimation pipelines for behavioral tracking of non-human primates, requiring less data and fewer cameras. This efficiency is also confirmed for a state-of-the-art human benchmark dataset. A behavioral experiment with real macaque monkeys demonstrates that animals perceive the generated animations as similar to genuine videos, and establishes an uncanny valley effect for bodies in monkeys.

animal behavior and cognition↗

bioRxiv2023

Theta activity discriminates high-level, species-specific body processes

Among social stimuli that trigger rapid reactions, body images occupy a prominent place. Given that bodies carry information about other agents intentions, actions and emotional expressions, a foundational question concerns the neural basis of body processing. Previous fMRI studies have investigated this but were not yet able to clarify the time course and its functional significance. The present EEG study investigated the role of slow oscillatory cortical activity in body processing and species-specificity. Human participants viewed naturalistic images of human and monkey bodies, faces, and objects, along with mosaic-scrambled versions to control for low-level visual features. Analysis of event-related theta power (4 - 7 Hz) combined with data-driven methods revealed a strong, body-evoked neural response that is specific to human bodies and likely originates from a widespread cortical region during a time window of 150 - 550 ms after the onset of the body image. Our results corroborate recent research proposing a widespread, species-specific cortical network of human body processing. We submit that this network may play an essential role in linking body processes to movement intentions.

neuroscience↗

bioRxiv2023

Stimulus expectations do not modulate visual event-related potentials in probabilistic cueing designs

Humans and other animals can learn and exploit repeating patterns that occur within their environments. These learned patterns can be used to form expectations about future sensory events. Several influential predictive coding models have been proposed to explain how learned expectations influence the activity of stimulus-selective neurons in the visual system. These models specify reductions in neural response measures when expectations are fulfilled (termed expectation suppression) and increases following surprising sensory events. However, there is currently scant evidence for expectation suppression in the visual system when confounding factors are taken into account. Effects of surprise have been observed in blood oxygen level dependent (BOLD) signals, but not when using electrophysiological measures. To provide a strong test for expectation suppression and surprise effects we performed a predictive cueing experiment while recording electroencephalographic (EEG) data. Participants (n=48) learned cue-face associations during a training session and were then exposed to these cue-face pairs in a subsequent experiment. Using univariate analyses of face-evoked event-related potentials (ERPs) we did not observe any differences across expected (90% probability), neutral (50%) and surprising (10%) face conditions. Across these comparisons, Bayes factors consistently favoured the null hypothesis throughout the time-course of the stimulus-evoked response. When using multivariate pattern analysis we did not observe above-chance classification of expected and surprising face-evoked ERPs. By contrast, we found robust within- and across-trial stimulus repetition effects. Our findings do not support predictive coding-based accounts that specify reduced prediction error signalling when perceptual expectations are fulfilled. They instead highlight the utility of other types of predictive processing models that describe expectation-related phenomena in the visual system without recourse to prediction error signalling. Highlights- We performed a probabilistic cueing experiment while recording EEG. - We tested for effects of fulfilled expectations, surprise, and image repetition. - No expectation-related effects were observed. - Robust within- and across-trial repetition effects were found. - We did not find support for predictive coding models of expectation effects.

neuroscience↗

bioRxiv2022

A large-scale brain network of species-specific dynamic human body perception

This ultrahigh field 7T fMRI study addressed the question of whether there exists a core network of brain areas at the service of different aspects of body perception. Participants viewed naturalistic videos of monkey and human faces, bodies, and objects along with mosaic-scrambled videos for control of low-level features. ICA-based network analysis was conducted to find body and species modulations at both the voxel and the network levels. Among the body areas, the highest species selectivity was found in the middle frontal gyrus and amygdala. Two large-scale networks were highly selective to bodies, dominated by the lateral occipital cortex and right superior temporal sulcus (STS) respectively. The right STS network showed high species selectivity, and its significant human body-induced node connectivity was focused around the extrastriate body area (EBA), STS, temporoparietal junction (TPJ), premotor cortex, and inferior frontal gyrus (IFG). The human body-specific network discovered here may serve as a brain-wide internal model of the human body serving as an entry point for a variety of processes relying on body descriptions as part of their more specific categorization, action, or expression recognition functions.

neuroscience↗

bioRxiv2021

Ad26.COV2.S elicited neutralizing activity against Delta and other SARS-CoV-2 variants of concern

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve and recently emerging variants with substitutions in the Spike protein have led to growing concerns over increased transmissibility and decreased vaccine coverage due to immune evasion. Here, sera from recipients of a single dose of our Ad26.COV2.S COVID-19 vaccine were tested for neutralizing activity against several SARS-CoV-2 variants of concern. All tested variants demonstrated susceptibility to Ad26.COV2.S-induced serum neutralization albeit mainly reduced as compared to the B.1 strain. Most pronounced reduction was observed for the B.1.351 (Beta; 3.6-fold) and P.1 (Gamma; 3.4-fold) variants that contain similar mutations in the receptor-binding domain (RBD) while only a 1.6-fold reduction was observed for the widely spreading B.1.617.2 (Delta) variant.

immunology↗

bioRxiv2020

Ad26-vector based COVID-19 vaccine encoding a prefusion stabilized SARS-CoV-2 Spike immunogen induces potent humoral and cellular immune responses

Development of effective preventative interventions against SARS-CoV-2, the etiologic agent of COVID-19 is urgently needed. The viral surface spike (S) protein of SARS-CoV-2 is a key target for prophylactic measures as it is critical for the viral replication cycle and the primary target of neutralizing antibodies. We evaluated design elements previously shown for other coronavirus S protein-based vaccines to be successful, e.g. prefusion-stabilizing substitutions and heterologous signal peptides, for selection of a S-based SARS-CoV-2 vaccine candidate. In vitro characterization demonstrated that the introduction of stabilizing substitutions (i.e., furin cleavage site mutations and two consecutive prolines in the hinge region of S1) increased the ratio of neutralizing versus non-neutralizing antibody binding, suggestive for a prefusion conformation of the S protein. Furthermore, the wild type signal peptide was best suited for the correct cleavage needed for a natively-folded protein. These observations translated into superior immunogenicity in mice where the Ad26 vector encoding for a membrane-bound stabilized S protein with a wild type signal peptide elicited potent neutralizing humoral immunity and cellular immunity that was polarized towards Th1 IFN-{gamma}. This optimized Ad26 vector-based vaccine for SARS-CoV-2, termed Ad26.COV2.S, is currently being evaluated in a phase I clinical trial (ClinicalTrials.gov Identifier: NCT04436276).

immunology↗

bioRxiv2018

The impact of stimulus size and orientation on individual face decoding in monkey face-selective cortex.

Face-selective neurons in the monkey temporal cortex discharge at different rates in response to pictures of different faces. Here we tested whether the population response of neurons in the face-selective area ML (located in the middle Superior Temporal Sulcus) tolerates two affine transformations; one, picture-plane inversion, known to have a deleterious impact on the average response of face-selective neurons and the other, stimulus size, thought to have little or no impact on face-selective neurons. We recorded the response of 57 ML neurons in two monkeys. Face stimuli were presented at two sizes (10 and 5 degrees of visual angle) and two orientations (upright and inverted). The results indicate that different faces elicited distinct patterns of activity across ML neurons that were tolerant of changes in size. However, the results of the orientation manipulation were mixed; despite observing a reduced response to inverted faces, classifier performance was above chance for both upright and inverted faces and the classification score did not differ significantly for inverted and upright faces. We conclude that population responses in area ML to different faces are dependent on stimulus orientation but are more tolerant to changes in stimulus size.

neuroscience↗