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Saeedi A, Wang K, Nikpourian G, Bartels A, Logothetis NK, Totah NK, Watanabe M. Brightness illusions drive a neuronal response in the primary visual cortex under top-down modulation. Nat Commun 2024; 15:3141. [PMID: 38653975 DOI: 10.1038/s41467-024-46885-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Accepted: 03/13/2024] [Indexed: 04/25/2024] Open
Abstract
Brightness illusions are a powerful tool in studying vision, yet their neural correlates are poorly understood. Based on a human paradigm, we presented illusory drifting gratings to mice. Primary visual cortex (V1) neurons responded to illusory gratings, matching their direction selectivity for real gratings, and they tracked the spatial phase offset between illusory and real gratings. Illusion responses were delayed compared to real gratings, in line with the theory that processing illusions requires feedback from higher visual areas (HVAs). We provide support for this theory by showing a reduced V1 response to illusions, but not real gratings, following HVAs optogenetic inhibition. Finally, we used the pupil response (PR) as an indirect perceptual report and showed that the mouse PR matches the human PR to perceived luminance changes. Our findings resolve debates over whether V1 neurons are involved in processing illusions and highlight the involvement of feedback from HVAs.
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Affiliation(s)
- Alireza Saeedi
- Department of Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076, Tübingen, Germany
- Research Group Neurobiology of Magnetoreception, Max Planck Institute for Neurobiology of Behavior - caesar, 53175, Bonn, Germany
| | - Kun Wang
- Department of Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076, Tübingen, Germany
- Department of Physiology of Cognitive Processes, International Center for Primate Brain Research, Songjiang District, Shanghai, 201602, China
| | - Ghazaleh Nikpourian
- Department of Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076, Tübingen, Germany
| | - Andreas Bartels
- Department of Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076, Tübingen, Germany
- Department of Psychology, Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
- Bernstein Center for Computational Neuroscience, Tübingen, Germany
| | - Nikos K Logothetis
- Department of Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076, Tübingen, Germany
- Department of Physiology of Cognitive Processes, International Center for Primate Brain Research, Songjiang District, Shanghai, 201602, China
- Centre for Imaging Sciences, University of Manchester, Manchester, M139PT, UK
| | - Nelson K Totah
- Department of Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076, Tübingen, Germany.
- Helsinki Institute of Life Science (HILIFE), University of Helsinki, 00014, Helsinki, Finland.
- Faculty of Pharmacy, University of Helsinki, 00014, Helsinki, Finland.
- Neuroscience Center, University of Helsinki, 00014, Helsinki, Finland.
| | - Masataka Watanabe
- Department of Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, 72076, Tübingen, Germany.
- Department of Systems Innovation, School of Engineering, The University of Tokyo, Tokyo, Japan.
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Cornelissen NV, Mineikaitė R, Erguven M, Muthmann N, Peters A, Bartels A, Rentmeister A. Post-synthetic benzylation of the mRNA 5' cap via enzymatic cascade reactions. Chem Sci 2023; 14:10962-10970. [PMID: 37829022 PMCID: PMC10566477 DOI: 10.1039/d3sc03822j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 08/28/2023] [Indexed: 10/14/2023] Open
Abstract
mRNAs are emerging modalities for vaccination and protein replacement therapy. Increasing the amount of protein produced by stabilizing the transcript or enhancing translation without eliciting a strong immune response are major steps towards overcoming the present limitations and improving their therapeutic potential. The 5' cap is a hallmark of mRNAs and non-natural modifications can alter the properties of the entire transcript selectively. Here, we developed a versatile enzymatic cascade for regioselective benzylation of various biomolecules and applied it for post-synthetic modification of mRNA at the 5' cap to demonstrate its potential. Starting from six synthetic methionine analogues bearing (hetero-)benzyl groups, S-adenosyl-l-methionine analogues are formed and utilized for N7G-cap modification of mRNAs. This post-synthetic enzymatic modification exclusively modifies mRNAs at the terminal N7G, producing mRNAs with functional 5' caps. It avoids the wrong orientation of the 5' cap-a problem in common co-transcriptional capping. In the case of the 4-chlorobenzyl group, protein production was increased to 139% during in vitro translation and to 128-150% in four different cell lines. This 5' cap modification did not activate cytosolic pathogen recognition receptors TLR3, TLR7 or TLR8 significantly more than control mRNAs, underlining its potential to contribute to the development of future mRNA therapeutics.
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Affiliation(s)
- N V Cornelissen
- University of Münster, Department of Chemistry, Institute of Biochemistry Corrensstr. 36 48149 Münster Germany
| | - R Mineikaitė
- University of Münster, Department of Chemistry, Institute of Biochemistry Corrensstr. 36 48149 Münster Germany
| | - M Erguven
- University of Münster, Department of Chemistry, Institute of Biochemistry Corrensstr. 36 48149 Münster Germany
- University of Münster, Cells in Motion Interfaculty Centre Waldeyerstr. 15 48149 Münster Germany
| | - N Muthmann
- University of Münster, Department of Chemistry, Institute of Biochemistry Corrensstr. 36 48149 Münster Germany
| | - A Peters
- University of Münster, Department of Chemistry, Institute of Biochemistry Corrensstr. 36 48149 Münster Germany
| | - A Bartels
- University of Münster, Department of Chemistry, Institute of Biochemistry Corrensstr. 36 48149 Münster Germany
| | - A Rentmeister
- University of Münster, Department of Chemistry, Institute of Biochemistry Corrensstr. 36 48149 Münster Germany
- University of Münster, Cells in Motion Interfaculty Centre Waldeyerstr. 15 48149 Münster Germany
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3
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Bannert MM, Bartels A. Visual cortex: Big data analysis uncovers food specificity. Curr Biol 2022; 32:R1012-R1015. [PMID: 36220088 DOI: 10.1016/j.cub.2022.08.068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In visual cortex, anatomically distinct patches respond to distinct categories, such as faces or text. New research confirms this parcellation using unsupervised analysis of functional magnetic resonance imaging data obtained from humans viewing tens of thousands of images, discovering one more preference: for food.
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Affiliation(s)
- Michael M Bannert
- Vision and Cognition Lab, Centre for Integrative Neuroscience, Department of Psychology, University of Tübingen, Tübingen, Germany; Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Bernstein Center for Computational Neuroscience, Tübingen, Germany
| | - Andreas Bartels
- Vision and Cognition Lab, Centre for Integrative Neuroscience, Department of Psychology, University of Tübingen, Tübingen, Germany; Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Bernstein Center for Computational Neuroscience, Tübingen, Germany.
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4
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te Vrugt M, Bartels A, Kosch L, Feldmeyer L, Hollfoth V, Tölle I, Randau G, Michgehl U, Hotfilder M, Lanvers-Kaminsky C, Burkhardt B. FUNCTIONAL CHARACTERIZATION OF POTENTIAL DIAGNOSTIC TARGETS IN BURKITT-NHL. Leuk Res 2022. [DOI: 10.1016/s0145-2126(22)00265-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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5
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Adeboyeje G, Sierra M, Bartels A, Field M, Jhamb S, Buikema A, Joo S. 1471P Overall survival by BRCA and ATM mutation status in patients with metastatic pancreatic cancer: Findings from the PRIOR-2 study. Ann Oncol 2021. [DOI: 10.1016/j.annonc.2021.08.798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Foster C, Zhao M, Bolkart T, Black MJ, Bartels A, Bülthoff I. Separated and overlapping neural coding of face and body identity. Hum Brain Mapp 2021; 42:4242-4260. [PMID: 34032361 PMCID: PMC8356992 DOI: 10.1002/hbm.25544] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 04/15/2021] [Accepted: 05/13/2021] [Indexed: 11/25/2022] Open
Abstract
Recognising a person's identity often relies on face and body information, and is tolerant to changes in low‐level visual input (e.g., viewpoint changes). Previous studies have suggested that face identity is disentangled from low‐level visual input in the anterior face‐responsive regions. It remains unclear which regions disentangle body identity from variations in viewpoint, and whether face and body identity are encoded separately or combined into a coherent person identity representation. We trained participants to recognise three identities, and then recorded their brain activity using fMRI while they viewed face and body images of these three identities from different viewpoints. Participants' task was to respond to either the stimulus identity or viewpoint. We found consistent decoding of body identity across viewpoint in the fusiform body area, right anterior temporal cortex, middle frontal gyrus and right insula. This finding demonstrates a similar function of fusiform and anterior temporal cortex for bodies as has previously been shown for faces, suggesting these regions may play a general role in extracting high‐level identity information. Moreover, we could decode identity across fMRI activity evoked by faces and bodies in the early visual cortex, right inferior occipital cortex, right parahippocampal cortex and right superior parietal cortex, revealing a distributed network that encodes person identity abstractly. Lastly, identity decoding was consistently better when participants attended to identity, indicating that attention to identity enhances its neural representation. These results offer new insights into how the brain develops an abstract neural coding of person identity, shared by faces and bodies.
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Affiliation(s)
- Celia Foster
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany.,Max Planck Institute for Intelligent Systems, Tübingen, Germany.,International Max Planck Research School for Cognitive and Systems Neuroscience, University of Tübingen, Tübingen, Germany
| | - Mintao Zhao
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany.,School of Psychology, University of East Anglia, UK
| | - Timo Bolkart
- Max Planck Institute for Intelligent Systems, Tübingen, Germany
| | - Michael J Black
- Max Planck Institute for Intelligent Systems, Tübingen, Germany
| | - Andreas Bartels
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany.,Centre for Integrative Neuroscience, Tübingen, Germany.,Department of Psychology, University of Tübingen, Germany.,Bernstein Center for Computational Neuroscience, Tübingen, Germany
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7
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Grassi PR, Bartels A. Magic, Bayes and wows: A Bayesian account of magic tricks. Neurosci Biobehav Rev 2021; 126:515-527. [PMID: 33838209 DOI: 10.1016/j.neubiorev.2021.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 03/05/2021] [Accepted: 04/01/2021] [Indexed: 10/21/2022]
Abstract
Magic tricks have enjoyed an increasing interest by scientists. However, most research in magic focused on isolated aspects of it and a conceptual understanding of magic, encompassing its distinct components and varieties, is missing. Here, we present an account of magic within the theory of Bayesian predictive coding. We present the "wow" effect of magic as an increase in surprise evoked by the prediction error between expected and observed data. We take into account prior knowledge of the observer, attention, and (mis-)direction of perception and beliefs by the magician to bias the observer's predictions and present a simple example for the modelling of the evoked surprise. The role of misdirection is described as everything that aims to maximize the surprise a trick evokes by the generation of novel beliefs, the exploitation of background knowledge and attentional control of the incoming information. Understanding magic within Bayesian predictive coding allows unifying all aspects of magic tricks within one framework, making it tractable, comparable and unifiable with other models in psychology and neuroscience.
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Affiliation(s)
- Pablo Rodrigo Grassi
- Department of Psychology, University of Tübingen, Schleichtstr. 4, 72076 Tübingen, Germany; Centre for Integrative Neurosciences, Otfried-Müllerstr. 25, 72075 Tübingen, Germany; Max-Planck Institute for Biological Cybernetics, Germany.
| | - Andreas Bartels
- Department of Psychology, University of Tübingen, Schleichtstr. 4, 72076 Tübingen, Germany; Centre for Integrative Neurosciences, Otfried-Müllerstr. 25, 72075 Tübingen, Germany; Max-Planck Institute for Biological Cybernetics, Germany.
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Hoenders R, Bartels A, Castelein S, Visser E, Booij S. An outpatient clinic for integrative mental health: Patient and treatment characteristics and health outcomes based on patient reported routine outcome monitoring data. Eur Psychiatry 2021. [PMCID: PMC9475823 DOI: 10.1192/j.eurpsy.2021.1041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
IntroductionThere is an increasing interest in integrative (mental) health care and a growth in centers offering such services, but a paucity of research on patient characteristics, diagnosis, treatments offered, the effects of those treatments and patient satisfaction.ObjectivesTo examine the course of mental health outcomes in the context of the nature and quality of care of outpatients at a center for integrative psychiatry in the Netherlands, as well as relevant sociodemographic, clinical, and treatment-related moderators of this course.MethodsBaseline patient demographics, clinical and treatment characteristics of 537 patients with a completed care episode between 2012 and 2019 were assessed. Satisfaction and mental health treatment outcomes were examined using routine outcome monitoring and analyzed with multilevel intention-to-treat models.ResultsTwo thirds of patients were woman (median age 41 years), predominantly with a primary diagnosis of mood or anxiety disorder. Mean number of treatment sessions was 49 (SD=94) and total clinical time was 54 hours (SD=109). Mean treatment duration was 460 days (SD=407). Ninety percent of the sample filled out one or more assessment(s). Of the individuals with a baseline assessment, 50% completed a follow-up. Significant improvements in symptomatology, social functioning, interpersonal functioning, wellbeing, resilience and quality of life were found. Clinical and scientific interpretation, moderator analyses and patient satisfaction will be presented at the conference.ConclusionsAlthough no definite conclusions can be drawn due to the naturalistic design and missing data, especially at follow-up, patients seem to improve on all measured domains, including psychopathology, functioning and wellbeing.
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Foster C, Bülthoff I, Bartels A, Zhao M. Investigating holistic face processing within and outside of face-responsive brain regions. Neuroimage 2020; 226:117565. [PMID: 33221444 DOI: 10.1016/j.neuroimage.2020.117565] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 09/18/2020] [Accepted: 11/10/2020] [Indexed: 10/23/2022] Open
Abstract
It has been shown that human faces are processed holistically (i.e. as indecomposable wholes, rather than by their component parts) and this holistic face processing is linked to brain activity in face-responsive brain regions. Although several brain regions outside of the face-responsive network are also sensitive to relational processing and perceptual grouping, whether these non-face-responsive regions contribute to holistic processing remains unclear. Here, we investigated holistic face processing in the composite face paradigm both within and outside of face-responsive brain regions. We recorded participants' brain activity using fMRI while they performed a composite face task. Behavioural results indicate that participants tend to judge the same top face halves as different when they are aligned with different bottom face halves but not when they are misaligned, demonstrating a composite face effect. Neuroimaging results revealed significant differences in responses to aligned and misaligned faces in the lateral occipital complex (LOC), and trends in the anterior part of the fusiform face area (FFA2) and transverse occipital sulcus (TOS), suggesting that these regions are sensitive to holistic versus part-based face processing. Furthermore, the retrosplenial cortex (RSC) and the parahippocampal place area (PPA) showed a pattern of neural activity consistent with a holistic representation of face identity, which also correlated with the strength of the behavioural composite face effect. These results suggest that neural activity in brain regions both within and outside of the face-responsive network contributes to the composite-face effect.
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Affiliation(s)
- Celia Foster
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany; International Max Planck Research School for Cognitive and Systems Neuroscience, University of Tübingen, Tübingen, Germany.
| | | | - Andreas Bartels
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Centre for Integrative Neuroscience, Tübingen, Germany; Department of Psychology, University of Tübingen, Tübingen, Germany; Bernstein Center for Computational Neuroscience, Tübingen, Germany
| | - Mintao Zhao
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany; School of Psychology, University of East Anglia, Norwich, UK.
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Zhaoping L, Grassi P, Zou J, Erb M, Scheffler K, Bartels A. Neural representation of illusory reversed depth in anti-correlated random-dot stereograms across visual cortical areas in central and peripheral visual fields: An fMRI study. J Vis 2020. [DOI: 10.1167/jov.20.11.1522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Li Zhaoping
- University of Tuebingen,
- Max Planck Institute for Biological Cybernetics
| | | | - Jinyou Zou
- Max Planck Institute for Biological Cybernetics
| | | | - Klaus Scheffler
- University of Tuebingen,
- Max Planck Institute for Biological Cybernetics
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Foster C, Zhao M, Bolkart T, Black MJ, Bartels A, Bülthoff I. Decoding the Viewpoint and Identity of Faces and Bodies. J Vis 2019. [DOI: 10.1167/19.10.54c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Celia Foster
- Max Planck Institute for Biological Cybernetics, Germany
- Max Planck Institute for Intelligent Systems, Germany
- Centre for Integrative Neuroscience, Germany
- Graduate Training Centre of Neuroscience, Tübingen, Germany
| | - Mintao Zhao
- Max Planck Institute for Biological Cybernetics, Germany
- School of Psychology, University of East Anglia, UK
| | - Timo Bolkart
- Max Planck Institute for Intelligent Systems, Germany
| | | | - Andreas Bartels
- Max Planck Institute for Biological Cybernetics, Germany
- Centre for Integrative Neuroscience, Germany
- Department of Psychology, University of Tübingen, Germany
- Bernstein Center for Computational Neuroscience, Tübingen, Germany
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12
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Foster C, Zhao M, Romero J, Black MJ, Mohler BJ, Bartels A, Bülthoff I. Decoding subcategories of human bodies from both body- and face-responsive cortical regions. Neuroimage 2019; 202:116085. [PMID: 31401238 DOI: 10.1016/j.neuroimage.2019.116085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 07/17/2019] [Accepted: 08/07/2019] [Indexed: 11/19/2022] Open
Abstract
Our visual system can easily categorize objects (e.g. faces vs. bodies) and further differentiate them into subcategories (e.g. male vs. female). This ability is particularly important for objects of social significance, such as human faces and bodies. While many studies have demonstrated category selectivity to faces and bodies in the brain, how subcategories of faces and bodies are represented remains unclear. Here, we investigated how the brain encodes two prominent subcategories shared by both faces and bodies, sex and weight, and whether neural responses to these subcategories rely on low-level visual, high-level visual or semantic similarity. We recorded brain activity with fMRI while participants viewed faces and bodies that varied in sex, weight, and image size. The results showed that the sex of bodies can be decoded from both body- and face-responsive brain areas, with the former exhibiting more consistent size-invariant decoding than the latter. Body weight could also be decoded in face-responsive areas and in distributed body-responsive areas, and this decoding was also invariant to image size. The weight of faces could be decoded from the fusiform body area (FBA), and weight could be decoded across face and body stimuli in the extrastriate body area (EBA) and a distributed body-responsive area. The sex of well-controlled faces (e.g. excluding hairstyles) could not be decoded from face- or body-responsive regions. These results demonstrate that both face- and body-responsive brain regions encode information that can distinguish the sex and weight of bodies. Moreover, the neural patterns corresponding to sex and weight were invariant to image size and could sometimes generalize across face and body stimuli, suggesting that such subcategorical information is encoded with a high-level visual or semantic code.
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Affiliation(s)
- Celia Foster
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Max Planck Institute for Intelligent Systems, Tübingen, Germany; Centre for Integrative Neuroscience, Tübingen, Germany.
| | - Mintao Zhao
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany; School of Psychology, University of East Anglia, UK
| | - Javier Romero
- Max Planck Institute for Intelligent Systems, Tübingen, Germany
| | - Michael J Black
- Max Planck Institute for Intelligent Systems, Tübingen, Germany
| | - Betty J Mohler
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Max Planck Institute for Intelligent Systems, Tübingen, Germany
| | - Andreas Bartels
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Centre for Integrative Neuroscience, Tübingen, Germany; Department of Psychology, University of Tübingen, Germany; Bernstein Center for Computational Neuroscience, Tübingen, Germany
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Beck M, Plötzing T, Maussang K, Palomo J, Colombelli R, Sagnes I, Mangeney J, Tignon J, Dhillon SS, Klatt G, Bartels A. High-speed THz spectroscopic imaging at ten kilohertz pixel rate with amplitude and phase contrast. Opt Express 2019; 27:10866-10872. [PMID: 31052940 DOI: 10.1364/oe.27.010866] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 03/28/2019] [Indexed: 06/09/2023]
Abstract
By combining the advantages of the high-speed ASOPS technology and efficient THz generation, we have realized a high-speed laser-based spectroscopic THz imaging system with more than 10,000 pixels per second acquisition speed and an excellent signal-to-noise ratio of more than 100. Unlike THz line cameras or mm-wave intensity detectors, the present device allows for a much higher spatial resolution and attributes each imaging pixel with phase and amplitude information up to several THz while simultaneously maintaining a very high scanning speed unmatched by any other technique presented so far. The high-speed acquisition allows for samples to be scanned even at sample velocities of 5 m/s or higher while preserving the fundamental resolution limit of the THz radiation, which is on the order of 500 µm in the present case.
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Schindler A, Bartels A. Human V6 Integrates Visual and Extra-Retinal Cues during Head-Induced Gaze Shifts. iScience 2018; 7:191-197. [PMID: 30267680 PMCID: PMC6153141 DOI: 10.1016/j.isci.2018.09.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 07/13/2018] [Accepted: 09/04/2018] [Indexed: 11/18/2022] Open
Abstract
A key question in vision research concerns how the brain compensates for self-induced eye and head movements to form the world-centered, spatiotopic representations we perceive. Although human V3A and V6 integrate eye movements with vision, it is unclear which areas integrate head motion signals with visual retinotopic representations, as fMRI typically prevents head movement executions. Here we examined whether human early visual cortex V3A and V6 integrate these signals. A previously introduced paradigm allowed participant head movement during trials, but stabilized the head during data acquisition utilizing the delay between blood-oxygen-level-dependent (BOLD) and neural signals. Visual stimuli simulated either a stable environment or one with arbitrary head-coupled visual motion. Importantly, both conditions were matched in retinal and head motion. Contrasts revealed differential responses in human V6. Given the lack of vestibular responses in primate V6, these results suggest multi-modal integration of visual with neck efference copy signals or proprioception in V6. Setup with head-mounted goggles and head movement during fMRI Simulation of forward flow in stable or unstable world during head rotation Human V6 integrates visual self-motion with head motion signals Likely mediated by efference copy or proprioception as V6 lacks vestibular input
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Affiliation(s)
- Andreas Schindler
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, Tübingen 72076, Germany; Department of Psychology, University of Tübingen, Tübingen 72076, Germany; Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany; Centre for Integrative Neuroscience & MEG Center, University of Tübingen, Tübingen 72076, Germany.
| | - Andreas Bartels
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, Tübingen 72076, Germany; Department of Psychology, University of Tübingen, Tübingen 72076, Germany; Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany.
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15
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Bannert M, Bartels A. Human V4 Activity Patterns Predict Behavioral Performance in Imagery of Object Color. J Vis 2018. [DOI: 10.1167/18.10.871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Michael Bannert
- Werner Reichardt Centre for Integrative Neuroscience, University of TübingenBernstein Center for Computational Neuroscience
| | - Andreas Bartels
- Werner Reichardt Centre for Integrative Neuroscience, University of TübingenBernstein Center for Computational Neuroscience
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16
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Foster C, Zhao M, Bartels A, Bülthoff I. Neural Correlates of Holistic Face Processing. J Vis 2018. [DOI: 10.1167/18.10.1085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Celia Foster
- Max Planck Institute for Biological Cybernetics, GermanyGraduate Training Centre of Neuroscience, International Max Planck Research School, University of Tübingen, Germany
| | - Mintao Zhao
- Max Planck Institute for Biological Cybernetics, GermanySchool of Psychology, University of East Anglia, UK
| | - Andreas Bartels
- Max Planck Institute for Biological Cybernetics, GermanyCentre for Integrative Neuroscience, Germany
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Noer JB, Bartels A, Friis S, Brünner N, Moreira J. PO-186 In vitro and clinical studies of the role of MHC class II invariant chain (CD74) in breast cancer. ESMO Open 2018. [DOI: 10.1136/esmoopen-2018-eacr25.225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Nau M, Schindler A, Bartels A. Real-motion signals in human early visual cortex. Neuroimage 2018; 175:379-387. [PMID: 29649561 DOI: 10.1016/j.neuroimage.2018.04.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 04/06/2018] [Accepted: 04/08/2018] [Indexed: 11/25/2022] Open
Abstract
Eye movements induce visual motion that can complicate the stable perception of the world. The visual system compensates for such self-induced visual motion by integrating visual input with efference copies of eye movement commands. This mechanism is central as it does not only support perceptual stability but also mediates reliable perception of world-centered objective motion. In humans, it remains elusive whether visual motion responses in early retinotopic cortex are driven by objective motion or by retinal motion associated with it. To address this question, we used fMRI to examine functional responses of sixteen visual areas to combinations of planar objective motion and pursuit eye movements. Observers were exposed to objective motion that was faster, matched or slower relative to pursuit, allowing us to compare conditions that differed in objective motion velocity while retinal motion and eye movement signals were matched. Our results show that not only higher level motion regions such as V3A and V6, but also early visual areas signaled the velocity of objective motion, hence the product of integrating retinal with non-retinal signals. These results shed new light on mechanisms that mediate perceptual stability and real-motion perception, and show that extra-retinal signals related to pursuit eye movements influence processing in human early visual cortex.
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Affiliation(s)
- Matthias Nau
- Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Trondheim, Norway; Egil & Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Trondheim, Norway; Norwegian University of Science and Technology, Trondheim, Norway
| | - Andreas Schindler
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany; Department of Psychology, University of Tübingen, Tübingen, Germany; Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Andreas Bartels
- Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany; Department of Psychology, University of Tübingen, Tübingen, Germany; Max Planck Institute for Biological Cybernetics, Tübingen, Germany; Bernstein Centre for Computational Neuroscience, Tübingen, Germany.
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Schindler A, Bartels A. Connectivity Reveals Sources of Predictive Coding Signals in Early Visual Cortex During Processing of Visual Optic Flow. Cereb Cortex 2018; 27:2885-2893. [PMID: 27222382 DOI: 10.1093/cercor/bhw136] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Superimposed on the visual feed-forward pathway, feedback connections convey higher level information to cortical areas lower in the hierarchy. A prominent framework for these connections is the theory of predictive coding where high-level areas send stimulus interpretations to lower level areas that compare them with sensory input. Along these lines, a growing body of neuroimaging studies shows that predictable stimuli lead to reduced blood oxygen level-dependent (BOLD) responses compared with matched nonpredictable counterparts, especially in early visual cortex (EVC) including areas V1-V3. The sources of these modulatory feedback signals are largely unknown. Here, we re-examined the robust finding of relative BOLD suppression in EVC evident during processing of coherent compared with random motion. Using functional connectivity analysis, we show an optic flow-dependent increase of functional connectivity between BOLD suppressed EVC and a network of visual motion areas including MST, V3A, V6, the cingulate sulcus visual area (CSv), and precuneus (Pc). Connectivity decreased between EVC and 2 areas known to encode heading direction: entorhinal cortex (EC) and retrosplenial cortex (RSC). Our results provide first evidence that BOLD suppression in EVC for predictable stimuli is indeed mediated by specific high-level areas, in accord with the theory of predictive coding.
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Affiliation(s)
- Andreas Schindler
- Vision and Cognition Lab, Centre for Integrative Neuroscience and.,Department of Psychology, University of Tübingen, Tübingen 72076, Germany.,Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany
| | - Andreas Bartels
- Vision and Cognition Lab, Centre for Integrative Neuroscience and.,Department of Psychology, University of Tübingen, Tübingen 72076, Germany.,Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany
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20
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Schindler A, Bartels A. Integration of visual and non-visual self-motion cues during voluntary head movements in the human brain. Neuroimage 2018; 172:597-607. [PMID: 29427850 DOI: 10.1016/j.neuroimage.2018.02.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 01/30/2018] [Accepted: 02/03/2018] [Indexed: 12/19/2022] Open
Abstract
Our phenomenological experience of the stable world is maintained by continuous integration of visual self-motion with extra-retinal signals. However, due to conventional constraints of fMRI acquisition in humans, neural responses to visuo-vestibular integration have only been studied using artificial stimuli, in the absence of voluntary head-motion. We here circumvented these limitations and let participants to move their heads during scanning. The slow dynamics of the BOLD signal allowed us to acquire neural signal related to head motion after the observer's head was stabilized by inflatable aircushions. Visual stimuli were presented on head-fixed display goggles and updated in real time as a function of head-motion that was tracked using an external camera. Two conditions simulated forward translation of the participant. During physical head rotation, the congruent condition simulated a stable world, whereas the incongruent condition added arbitrary lateral motion. Importantly, both conditions were precisely matched in visual properties and head-rotation. By comparing congruent with incongruent conditions we found evidence consistent with the multi-modal integration of visual cues with head motion into a coherent "stable world" percept in the parietal operculum and in an anterior part of parieto-insular cortex (aPIC). In the visual motion network, human regions MST, a dorsal part of VIP, the cingulate sulcus visual area (CSv) and a region in precuneus (Pc) showed differential responses to the same contrast. The results demonstrate for the first time neural multimodal interactions between precisely matched congruent versus incongruent visual and non-visual cues during physical head-movement in the human brain. The methodological approach opens the path to a new class of fMRI studies with unprecedented temporal and spatial control over visuo-vestibular stimulation.
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Affiliation(s)
- Andreas Schindler
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Tübingen 72076, Germany; Department of Psychology, University of Tübingen, Tübingen 72076, Germany; Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany.
| | - Andreas Bartels
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Tübingen 72076, Germany; Department of Psychology, University of Tübingen, Tübingen 72076, Germany; Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany.
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21
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Bannert MM, Bartels A. Invariance of surface color representations across illuminant changes in the human cortex. Neuroimage 2017; 158:356-370. [PMID: 28673878 DOI: 10.1016/j.neuroimage.2017.06.079] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 06/16/2017] [Accepted: 06/29/2017] [Indexed: 11/24/2022] Open
Abstract
A central problem in color vision is that the light reaching the eye from a given surface can vary dramatically depending on the illumination. Despite this, our color percept, the brain's estimate of surface reflectance, remains remarkably stable. This phenomenon is called color constancy. Here we investigated which human brain regions represent surface color in a way that is invariant with respect to illuminant changes. We used physically realistic rendering methods to display natural yet abstract 3D scenes that were displayed under three distinct illuminants. The scenes embedded, in different conditions, surfaces that differed in their surface color (i.e. in their reflectance property). We used multivariate fMRI pattern analysis to probe neural coding of surface reflectance and illuminant, respectively. While all visual regions encoded surface color when viewed under the same illuminant, we found that only in V1 and V4α surface color representations were invariant to illumination changes. Along the visual hierarchy there was a gradient from V1 to V4α to increasingly encode surface color rather than illumination. Finally, effects of a stimulus manipulation on individual behavioral color constancy indices correlated with neural encoding of the illuminant in hV4. This provides neural evidence for the Equivalent Illuminant Model. Our results provide a principled characterization of color constancy mechanisms across the visual hierarchy, and demonstrate complementary contributions in early and late processing stages.
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Affiliation(s)
- Michael M Bannert
- Vision and Cognition Lab, Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, 72076 Tübingen, Germany; Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany; Department of Psychology, University of Tübingen, 72076 Tübingen, Germany; International Max Planck Research School for Cognitive and Systems Neuroscience, 72076 Tübingen, Germany.
| | - Andreas Bartels
- Vision and Cognition Lab, Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany; Bernstein Center for Computational Neuroscience, 72076 Tübingen, Germany; Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany; Department of Psychology, University of Tübingen, 72076 Tübingen, Germany.
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Grassi PR, Zaretskaya N, Bartels A. Scene segmentation in early visual cortex during suppression of ventral stream regions. Neuroimage 2017; 146:71-80. [DOI: 10.1016/j.neuroimage.2016.11.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 11/06/2016] [Accepted: 11/10/2016] [Indexed: 10/20/2022] Open
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Terebessy A, Voigt K, Riemenschneider H, Balázs P, Balogh E, Bartels A, Faubl N, Füzesi Z, Balla C, Horváth F, Schelling J, Kiss I, Cseh K, Bergmann A. Alcohol consumption of German medical students: comparing study home and abroad. Eur J Public Health 2016. [DOI: 10.1093/eurpub/ckw172.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Kriz J, Seegenschmiedt H, Bartels A, Micke O, Muecke R, Schaefer U, Haverkamp U, Eich H. Updated Strategies in the Treatment of Benign Diseases—A Patterns of Care Study of the German Cooperative Group on Benign Diseases. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2016.06.1889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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25
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Bannert M, Bartels A. The invariance of surface color representations across illuminant changes in the human cortex. J Vis 2016. [DOI: 10.1167/16.12.1155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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26
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Balskus K, Schilt S, Wittwer VJ, Brochard P, Ploetzing T, Jornod N, McCracken RA, Zhang Z, Bartels A, Reid DT, Südmeyer T. Frequency comb metrology with an optical parametric oscillator. Opt Express 2016; 24:8370-8381. [PMID: 27137274 DOI: 10.1364/oe.24.008370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report on the first demonstration of absolute frequency comb metrology with an optical parametric oscillator (OPO) frequency comb. The synchronously-pumped OPO operated in the 1.5-µm spectral region and was referenced to an H-maser atomic clock. Using different techniques, we thoroughly characterized the frequency noise power spectral density (PSD) of the repetition rate frep, of the carrier-envelope offset frequency fCEO, and of an optical comb line νN. The comb mode optical linewidth at 1557 nm was determined to be ~70 kHz for an observation time of 1 s from the measured frequency noise PSD, and was limited by the stability of the microwave frequency standard available for the stabilization of the comb repetition rate. We achieved a tight lock of the carrier envelope offset frequency with only ~300 mrad residual integrated phase noise, which makes its contribution to the optical linewidth negligible. The OPO comb was used to measure the absolute optical frequency of a near-infrared laser whose second-harmonic component was locked to the F = 2→3 transition of the 87Rb D2 line at 780 nm, leading to a measured transition frequency of νRb = 384,228,115,346 ± 16 kHz. We performed the same measurement with a commercial fiber-laser comb operating in the 1.5-µm region. Both the OPO comb and the commercial fiber comb achieved similar performance. The measurement accuracy was limited by interferometric noise in the fibered setup of the Rb-stabilized laser.
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Bartels A, Voigt K, Riemenschneider H, Nitschke-Bertaud M, Bergmann A. [Preferred Medical Specialties of Medical Students in Contrast to the Need for General Practitioners in Saxony]. Gesundheitswesen 2016; 79:188-194. [PMID: 27077318 DOI: 10.1055/s-0042-102339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Aim of the study: Especially in the rural areas of Germany, there are not enough general practitioners (GPs) for primary care. Preferred medical specialties of medical students can help get an estimate of the number of future GPs. This study compares this estimate to the current need for GPs in Saxony. Methods: 587 medical students at the second, sixth and tenth semester were invited to take part in an anonymous cross-sectional study regarding their specialty preferences at the Technical University Dresden. Based on the data of the medical requirements for Saxony, 4 model calculations were generated for comparison of the estimated numbers of future GPs and the current need for GPs. Results: The most commonly preferred medical specialties were surgery (19.1%), internal medicine (12.9%), pediatrics (11.6%) and general practice (9.9%). A significant increase in specialist preference for GP was observed from the sixth (4.9%) to the tenth semester (14.0%). The model calculations show that approximately 29% to 111% of the open positions for GPs could be filled by the potential new GPs from Dresden. Conclusion: Currently, medical students planning to become GPs cannot meet the corresponding need for GPs. Future studies should include the points of view of students, continuing education assistants, GPs and patients.
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Affiliation(s)
- A Bartels
- Bereich Allgemeinmedizin / Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus Dresden, Dresden
| | - K Voigt
- Bereich Allgemeinmedizin / Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus Dresden, Dresden
| | - H Riemenschneider
- Bereich Allgemeinmedizin / Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus Dresden, Dresden
| | - M Nitschke-Bertaud
- Bereich Allgemeinmedizin / Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus Dresden, Dresden
| | - A Bergmann
- Bereich Allgemeinmedizin / Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus Dresden, Dresden
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Schindler A, Bartels A. Visual high-level regions respond to high-level stimulus content in the absence of low-level confounds. Neuroimage 2016; 132:520-525. [PMID: 26975552 DOI: 10.1016/j.neuroimage.2016.03.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 01/21/2016] [Accepted: 03/04/2016] [Indexed: 11/24/2022] Open
Abstract
High-level regions of the ventral stream exhibit strong category selectivity to stimuli such as faces, houses, or objects. However, recent studies suggest that at least part of this selectivity stems from low-level differences inherent to images of the different categories. For example, visual outdoor and indoor scenes as well as houses differ in spatial frequency, rectilinearity and obliqueness when compared to face or object images. Correspondingly, scene responsive para-hippocampal place area (PPA) showed strong preference to low-level properties of visual scenes also in the absence of high-level scene content. This raises the question whether all high-level responses in PPA, the fusiform face area (FFA), or the object-responsive lateral occipital compex (LOC) may actually be explained by systematic differences in low-level features. In the present study we contrasted two classes of simple stimuli consisting of ten rectangles each. While both were matched in visual low-level features only one class of rectangle arrangements gave rise to a percept compatible with a high-level 3D layout such as a scene or an object. We found that areas PPA, transverse occipital sulcus (TOS, also referred to as occipital place area, OPA), as well as FFA and LOC showed robust responses to the visual scene class compared to the low-level matched control. Our results suggest that visual category responsive regions are not purely driven by low-level visual features but also by the high-level perceptual stimulus interpretation.
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Affiliation(s)
- Andreas Schindler
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Department of Psychology, University of Tübingen, 72076 Tübingen, Germany.
| | - Andreas Bartels
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Str. 25, 72076 Tübingen, Germany; Department of Psychology, University of Tübingen, 72076 Tübingen, Germany.
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Schindler A, Bartels A. Motion parallax links visual motion areas and scene regions. Neuroimage 2015; 125:803-812. [PMID: 26515906 DOI: 10.1016/j.neuroimage.2015.10.066] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 09/09/2015] [Accepted: 10/24/2015] [Indexed: 11/15/2022] Open
Abstract
When we move, the retinal velocities of objects in our surrounding differ according to their relative distances and give rise to a powerful three-dimensional visual cue referred to as motion parallax. Motion parallax allows us to infer our surrounding's 3D structure as well as self-motion based on 2D retinal information. However, the neural substrates mediating the link between visual motion and scene processing are largely unexplored. We used fMRI in human observers to study motion parallax by means of an ecologically relevant yet highly controlled stimulus that mimicked the observer's lateral motion past a depth-layered scene. We found parallax selective responses in parietal regions IPS3 and IPS4, and in a region lateral to scene selective occipital place area (OPA). The traditionally defined scene responsive regions OPA, the para-hippocampal place area (PPA) and the retrosplenial cortex (RSC) did not respond to parallax. During parallax processing, the occipital parallax selective region entertained highly specific functional connectivity with IPS3 and with scene selective PPA. These results establish a network linking dorsal motion and ventral scene processing regions specifically during parallax processing, which may underlie the brain's ability to derive 3D scene information from motion parallax.
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Affiliation(s)
- Andreas Schindler
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Tübingen 72076, Germany.
| | - Andreas Bartels
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Tübingen 72076, Germany.
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Korkmaz Hacialihafiz D, Bartels A. Motion responses in scene-selective regions. Neuroimage 2015; 118:438-44. [DOI: 10.1016/j.neuroimage.2015.06.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 05/18/2015] [Accepted: 06/09/2015] [Indexed: 10/23/2022] Open
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Abstract
In the current study we examined whether timeline-reversals and emotional direction of dynamic facial expressions affect subjective experience of human observers. We recorded natural movies of faces that increased or decreased their expressions of fear, and played them either in the natural frame order or reversed from last to first frame (reversed timeline). This led to four conditions of increasing or decreasing fear, either following the natural or reversed temporal trajectory of facial dynamics. This 2-by-2 factorial design controlled for visual low-level properties, static visual content, and motion energy across the different factors. It allowed us to examine perceptual consequences that would occur if the timeline trajectory of facial muscle movements during the increase of an emotion are not the exact mirror of the timeline during the decrease. It additionally allowed us to study perceptual differences between increasing and decreasing emotional expressions. Perception of these time-dependent asymmetries have not yet been quantified. We found that three emotional measures, emotional intensity, artificialness of facial movement, and convincingness or plausibility of emotion portrayal, were affected by timeline-reversals as well as by the emotional direction of the facial expressions. Our results imply that natural dynamic facial expressions contain temporal asymmetries, and show that deviations from the natural timeline lead to a reduction of perceived emotional intensity and convincingness, and to an increase of perceived artificialness of the dynamic facial expression. In addition, they show that decreasing facial expressions are judged as less plausible than increasing facial expressions. Our findings are of relevance for both, behavioral as well as neuroimaging studies, as processing and perception are influenced by temporal asymmetries.
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Affiliation(s)
| | - Andreas Bartels
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
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Bartels A, Martin V, Bidoli E, Steigmeier-Raith S, Brühschwein A, Reese S, Köstlin R, Erhard M. Brachycephalic problems of pugs relevant to animal welfare. Anim Welf 2015. [DOI: 10.7120/09627286.24.3.327] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Zaretskaya N, Bartels A. Gestalt perception is associated with reduced parietal beta oscillations. Neuroimage 2015; 112:61-69. [DOI: 10.1016/j.neuroimage.2015.02.049] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 01/30/2015] [Accepted: 02/23/2015] [Indexed: 12/19/2022] Open
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Meyer P, Bartels A, Heneweer C, Seeger M, Holl-Ulrich K, Duwendag D, Saeger M, Schröder J, Kopetsch C, Zimmermann P, Jansen O, Both M. Diagnostik der Riesenzellarteriitis: Untersuchungen der humanen Arteria temporalis im Hochfrequenzbereich mit einem Kleintier-Ultraschallgerät. ROFO-FORTSCHR RONTG 2015. [DOI: 10.1055/s-0035-1551009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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35
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Reinl M, Bartels A. Face processing regions are sensitive to distinct aspects of temporal sequence in facial dynamics. Neuroimage 2014; 102 Pt 2:407-15. [PMID: 25132020 DOI: 10.1016/j.neuroimage.2014.08.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 07/25/2014] [Accepted: 08/04/2014] [Indexed: 12/16/2022] Open
Abstract
Facial movement conveys important information for social interactions, yet its neural processing is poorly understood. Computational models propose that shape- and temporal sequence sensitive mechanisms interact in processing dynamic faces. While face processing regions are known to respond to facial movement, their sensitivity to particular temporal sequences has barely been studied. Here we used fMRI to examine the sensitivity of human face-processing regions to two aspects of directionality in facial movement trajectories. We presented genuine movie recordings of increasing and decreasing fear expressions, each of which were played in natural or reversed frame order. This two-by-two factorial design matched low-level visual properties, static content and motion energy within each factor, emotion-direction (increasing or decreasing emotion) and timeline (natural versus artificial). The results showed sensitivity for emotion-direction in FFA, which was timeline-dependent as it only occurred within the natural frame order, and sensitivity to timeline in the STS, which was emotion-direction-dependent as it only occurred for decreased fear. The occipital face area (OFA) was sensitive to the factor timeline. These findings reveal interacting temporal sequence sensitive mechanisms that are responsive to both ecological meaning and to prototypical unfolding of facial dynamics. These mechanisms are temporally directional, provide socially relevant information regarding emotional state or naturalness of behavior, and agree with predictions from modeling and predictive coding theory.
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Affiliation(s)
- Maren Reinl
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, and Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany
| | - Andreas Bartels
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, and Max Planck Institute for Biological Cybernetics, Tübingen 72076, Germany.
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Bannert M, Bartels A. Decoding the Yellow of a Gray Banana. Curr Biol 2013; 23:2268-2272. [DOI: 10.1016/j.cub.2013.09.016] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 08/15/2013] [Accepted: 09/06/2013] [Indexed: 11/29/2022]
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Watanabe M, Bartels A, Macke JH, Murayama Y, Logothetis NK. Temporal jitter of the BOLD signal reveals a reliable initial dip and improved spatial resolution. Curr Biol 2013; 23:2146-50. [PMID: 24139737 DOI: 10.1016/j.cub.2013.08.057] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 08/26/2013] [Accepted: 08/27/2013] [Indexed: 10/26/2022]
Abstract
fMRI, one of the most important noninvasive brain imaging methods, relies on the blood oxygen level-dependent (BOLD) signal, whose precise underpinnings are still not fully understood. It is a widespread assumption that the components of the hemodynamic response function (HRF) are fixed relative to each other in time, leading most studies as well as analysis tools to focus on trial-averaged responses, thus using or estimating a condition- or location-specific "canonical HRF". In the current study, we examined the nature of the variability of the BOLD response and asked in particular whether the positive BOLD peak is subject to trial-to-trial temporal jitter. Our results show that the positive peak of the stimulus-evoked BOLD signal exhibits a trial-to-trial temporal jitter on the order of seconds. Moreover, the trial-to-trial variability can be exploited to uncover the initial dip in the majority of voxels by pooling trial responses with large peak latencies. Initial dips exposed by this procedure possess higher spatial resolution compared to the positive BOLD signal in the human visual cortex. These findings allow for the reliable observation of fMRI signals that are physiologically closer to neural activity, leading to improvements in both temporal and spatial resolution.
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Affiliation(s)
- Masataka Watanabe
- School of Engineering, University of Tokyo, 113-0033 Tokyo, Japan; Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany; RIKEN Brain Science Institute, Wako, 351-0198 Saitama, Japan.
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Conrad V, Kleiner M, Bartels A, Hartcher O'Brien J, Bülthoff HH, Noppeney U. Naturalistic stimulus structure determines the integration of audiovisual looming signals in binocular rivalry. PLoS One 2013; 8:e70710. [PMID: 24015176 PMCID: PMC3754975 DOI: 10.1371/journal.pone.0070710] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 06/26/2013] [Indexed: 11/19/2022] Open
Abstract
Rapid integration of biologically relevant information is crucial for the survival of an organism. Most prominently, humans should be biased to attend and respond to looming stimuli that signal approaching danger (e.g. predator) and hence require rapid action. This psychophysics study used binocular rivalry to investigate the perceptual advantage of looming (relative to receding) visual signals (i.e. looming bias) and how this bias can be influenced by concurrent auditory looming/receding stimuli and the statistical structure of the auditory and visual signals. Subjects were dichoptically presented with looming/receding visual stimuli that were paired with looming or receding sounds. The visual signals conformed to two different statistical structures: (1) a 'simple' random-dot kinematogram showing a starfield and (2) a "naturalistic" visual Shepard stimulus. Likewise, the looming/receding sound was (1) a simple amplitude- and frequency-modulated (AM-FM) tone or (2) a complex Shepard tone. Our results show that the perceptual looming bias (i.e. the increase in dominance times for looming versus receding percepts) is amplified by looming sounds, yet reduced and even converted into a receding bias by receding sounds. Moreover, the influence of looming/receding sounds on the visual looming bias depends on the statistical structure of both the visual and auditory signals. It is enhanced when audiovisual signals are Shepard stimuli. In conclusion, visual perception prioritizes processing of biologically significant looming stimuli especially when paired with looming auditory signals. Critically, these audiovisual interactions are amplified for statistically complex signals that are more naturalistic and known to engage neural processing at multiple levels of the cortical hierarchy.
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Affiliation(s)
- Verena Conrad
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Mario Kleiner
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Andreas Bartels
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
- Werner Reichardt Centre for Integrative Neurosciences, Tübingen, Germany
| | | | - Heinrich H. Bülthoff
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
- Department of Brain and Cognitive Engineering, Korea University, Anam-dong, Seongbuk-gu, Seoul, Korea
| | - Uta Noppeney
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
- Computational Neuroscience and Cognitive Robotics Centre, University of Birmingham, Birmingham, United Kingdom
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Riemenschneider H, Hirsch K, Bartels A, Kämpfe C, Voigt K, Kugler J, Bergmann A. [Sexual risk behaviour of nursing students. A cross-sectional study at nursing schools in Saxony-Anhalt]. Gesundheitswesen 2013; 76:333-5. [PMID: 23868651 DOI: 10.1055/s-0033-1347261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
AIM This work describes the sexual risk behaviour of nursing students. METHODS 22 of 23 state-approved nursing schools in Saxony-Anhalt, Germany, participated in this cross-sectional study (study period 7/2005-5/2006). Participation was voluntarily and anonymous. RESULTS More male than female students (59.6% vs. 44.8%) used condoms to prevent STIs. More female students (58.9% vs. 43.4%) reported constant partnership with just one partner as an STI prevention method (chi² test, p<0.005). 29.6% of the nursing students reported >1 sexual partner in the past 12 months. 3.9% of the students demanded an HIV test from the partner, 69.3% had never tested themselves for HIV. 10.2% used no prevention against STIs. CONCLUSIONS Nursing students should be sensitised for sexual risk behaviour and STIs. This should be included in the content of teaching throughout the education, not least since nursing students are multiplicators and have an influence on health behaviour of the patients.
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Affiliation(s)
- H Riemenschneider
- Bereich Allgemeinmedizin, Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus der TU Dresden
| | - K Hirsch
- Krankenpflegeschule des Klinikums Dorothea Christiane Erxleben, Quedlinburg
| | - A Bartels
- Bereich Allgemeinmedizin, Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus der TU Dresden
| | - C Kämpfe
- Bereich Allgemeinmedizin, Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus der TU Dresden
| | - K Voigt
- Bereich Allgemeinmedizin, Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus der TU Dresden
| | - J Kugler
- Lehrstuhl Gesundheitswissenschaften/Public Health der Medizinischen Fakultät Carl, Gustav Carus der TU Dresden
| | - A Bergmann
- Bereich Allgemeinmedizin, Medizinische Klinik III, Universitätsklinikum Carl Gustav Carus der TU Dresden
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Abstract
MOTIVATION Imaging mass spectrometry has emerged in the past decade as a label-free, spatially resolved and multi-purpose bioanalytical technique for direct analysis of biological samples. However, solving two everyday data analysis problems still requires expert judgment: (i) the detection of unknown molecules and (ii) the testing for presence of known molecules. RESULTS We developed a measure of spatial chaos of a molecular image corresponding to a mass-to-charge value, which is a proxy for the molecular presence, and developed methods solving considered problems. The statistical evaluation was performed on a dataset from a rat brain section with test sets of molecular images selected by an expert. The measure of spatial chaos has shown high agreement with expert judges. The method for detection of unknown molecules allowed us to find structured molecular images corresponding to spectral peaks of any low intensity. The test for presence applied to a list of endogenous peptides ranked them according to the proposed measure of their presence in the sample. AVAILABILITY The source code and test sets of mass-to-charge images are available at http://www.math.uni-bremen.de/∼theodore. SUPPLEMENTARY INFORMATION Supplementary materials are available at Bioinformatics online. CONTACT theodore@uni-bremen.de.
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Affiliation(s)
- Theodore Alexandrov
- Center for Industrial Mathematics, University of Bremen, 28359 Bremen, Germany.
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Hunold P, Bartels A, Oevermann E, Hollmann S, Marxsen J, Kovács A, Barkhausen J, Vogt FM. Lokoregionäres Lymphknoten-Staging bei kolorektalem Karzinom mittels CT: Ein neues Befundungsmodell für höhere diagnostische Genauigkeit. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Morber M, Bartels A, Erhard MH. [Inappropriately rough play behaviour and predatory attacks against people by a tomcat. A case report]. Tierarztl Prax Ausg K Kleintiere Heimtiere 2013; 41:117-122. [PMID: 23608967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/09/2012] [Accepted: 08/14/2012] [Indexed: 06/02/2023]
Abstract
The owner of a 6-months-old tomcat came to seek help because the cat had attacked her face on a near-daily basis. Through a detailed behavioural history, the cat's behaviour was diagnosed as human-directed predatory attack behaviour, play-related aggression and reduced motor as well as emotional self-control. Within a few weeks, behavioural therapy produced a significant improvement. After 5 months of therapy, the cat showed neither predatory attacks nor inappropriately rough or aggressive behaviour in play towards its owner or other humans.
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Affiliation(s)
- M Morber
- Matina Morber, Tierärztliche Praxis, (Tätigkeitsschwerpunkt Verhaltenstherapie), Wendelsteinstraße 19, Erding.
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Schindler A, Bartels A. Parietal cortex codes for egocentric space beyond the field of view. Curr Biol 2012; 23:177-82. [PMID: 23260468 DOI: 10.1016/j.cub.2012.11.060] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 10/30/2012] [Accepted: 11/30/2012] [Indexed: 11/18/2022]
Abstract
Our subjective experience links covert visual and egocentric spatial attention seamlessly. However, the latter can extend beyond the visual field, covering all directions relative to our body. In contrast to visual representations, little is known about unseen egocentric representations in the healthy brain. Parietal cortex appears to be involved in both, because lesions in it can lead to deficits in visual attention, but also to a disorder of egocentric spatial awareness, known as hemispatial neglect. Here, we used a novel virtual reality paradigm to probe our participants' egocentric surrounding during fMRI recordings. We found that egocentric unseen space was represented by patterns of voxel activity in parietal cortex, independent of visual information. Intriguingly, the best decoding performances corresponded to brain areas associated with visual covert attention and reaching, as well as to lesion sites associated with spatial neglect.
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Affiliation(s)
- Andreas Schindler
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Strasse 25, 72076 Tübingen, Germany
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46
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Abstract
The perception of a melody is invariant to the absolute properties of its constituting notes, but depends on the relation between them-the melody's relative pitch profile. In fact, a melody's "Gestalt" is recognized regardless of the instrument or key used to play it. Pitch processing in general is assumed to occur at the level of the auditory cortex. However, it is unknown whether early auditory regions are able to encode pitch sequences integrated over time (i.e., melodies) and whether the resulting representations are invariant to specific keys. Here, we presented participants different melodies composed of the same 4 harmonic pitches during functional magnetic resonance imaging recordings. Additionally, we played the same melodies transposed in different keys and on different instruments. We found that melodies were invariantly represented by their blood oxygen level-dependent activation patterns in primary and secondary auditory cortices across instruments, and also across keys. Our findings extend common hierarchical models of auditory processing by showing that melodies are encoded independent of absolute pitch and based on their relative pitch profile as early as the primary auditory cortex.
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Affiliation(s)
- Andreas Schindler
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
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Affiliation(s)
- Andreas Bartels
- Vision and Cognition Lab, Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany
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Abstract
Little is known about mechanisms mediating a stable perception of the world during pursuit eye movements. Here, we used fMRI to determine to what extent human motion-responsive areas integrate planar retinal motion with nonretinal eye movement signals in order to discard self-induced planar retinal motion and to respond to objective ("real") motion. In contrast to other areas, V3A lacked responses to self-induced planar retinal motion but responded strongly to head-centered motion, even when retinally canceled by pursuit. This indicates a near-complete multimodal integration of visual with nonvisual planar motion signals in V3A. V3A could be mapped selectively and robustly in every single subject on this basis. V6 also reported head-centered planar motion, even when 3D flow was added to it, but was suppressed by retinal planar motion. These findings suggest a dominant contribution of human areas V3A and V6 to head-centered motion perception and to perceptual stability during eye movements.
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Affiliation(s)
- Elvira Fischer
- Vision and Cognition Lab, Centre of Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany
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Cavusoglu M, Bartels A, Yesilyurt B, Uludağ K. Retinotopic maps and hemodynamic delays in the human visual cortex measured using arterial spin labeling. Neuroimage 2012; 59:4044-54. [DOI: 10.1016/j.neuroimage.2011.10.056] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2011] [Revised: 10/10/2011] [Accepted: 10/18/2011] [Indexed: 11/27/2022] Open
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Stoewer S, Goense J, Keliris GA, Bartels A, Logothetis NK, Duncan J, Sigala N. An analysis approach for high-field fMRI data from awake non-human primates. PLoS One 2012; 7:e29697. [PMID: 22238636 PMCID: PMC3253095 DOI: 10.1371/journal.pone.0029697] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Accepted: 12/02/2011] [Indexed: 11/19/2022] Open
Abstract
fMRI experiments with awake non-human primates (NHP) have seen a surge of applications in recent years. However, the standard fMRI analysis tools designed for human experiments are not optimal for analysis of NHP fMRI data collected at high fields. There are several reasons for this, including the trial-based nature of NHP experiments, with inter-trial periods being of no interest, and segmentation artefacts and distortions that may result from field changes due to movement. We demonstrate an approach that allows us to address some of these issues consisting of the following steps: 1) Trial-based experimental design. 2) Careful control of subject movement. 3) Computer-assisted selection of trials devoid of artefacts and animal motion. 4) Nonrigid between-trial and rigid within-trial realignment of concatenated data from temporally separated trials and sessions. 5) Linear interpolation of inter-trial intervals and high-pass filtering of temporally continuous data 6) Removal of interpolated data and reconcatenation of datasets before statistical analysis with SPM. We have implemented a software toolbox, fMRI Sandbox (http://code.google.com/p/fmri-sandbox/), for semi-automated application of these processing steps that interfaces with SPM software. Here, we demonstrate that our methodology provides significant improvements for the analysis of awake monkey fMRI data acquired at high-field. The method may also be useful for clinical applications with subjects that are unwilling or unable to remain motionless for the whole duration of a functional scan.
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Affiliation(s)
- Steffen Stoewer
- Max Planck Institute for Biological Cybernetics, Tübingen, Germany.
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