A5074283953- Neural dynamics and brain function
- Visual perception and processing mechanisms
- Functional Brain Connectivity Studies
- Neurobiology and Insect Physiology Research
- Advanced Neuroimaging Techniques and Applications
- Neural and Behavioral Psychology Studies
- Neuroscience and Neural Engineering
- Neuroscience and Neuropharmacology Research
- Retinal Development and Disorders
- Photoreceptor and optogenetics research
- Advanced MRI Techniques and Applications
- Action Observation and Synchronization
- Neurogenesis and neuroplasticity mechanisms
- Axon Guidance and Neuronal Signaling
- Ultrasound and Hyperthermia Applications
- CCD and CMOS Imaging Sensors
- Photoacoustic and Ultrasonic Imaging
- Advanced Memory and Neural Computing
- Neurological disorders and treatments
- Aesthetic Perception and Analysis
- Face Recognition and Perception
- Child and Animal Learning Development
- Autism Spectrum Disorder Research
- Color perception and design
- Transcranial Magnetic Stimulation Studies
Otto-von-Guericke University Magdeburg
2019-2025
University of Oxford
2012-2021
Center for Behavioral Brain Sciences
2020-2021
Leibniz Institute for Neurobiology
2019-2021
Czech Academy of Sciences, Institute of Physiology
2016
Google (United States)
2016
To understand brain circuits it is necessary both to record and manipulate their activity. Transcranial ultrasound stimulation (TUS) a promising non-invasive technique. date, investigations report short-lived neuromodulatory effects, but deliver on its full potential for research therapy, protocols are required that induce longer-lasting ‘offline’ changes. Here, we present TUS protocol modulates activation in macaques more than one hour after 40 s of stimulation, while circumventing auditory...
The role of the primate middle temporal area (MT) in depth perception was examined by considering trial-to-trial correlations between neuronal activity and reported sensations. A set moving random dots portrayed a cylinder rotating about its principal axis. In this structure-from-motion stimulus, direction rotation is ambiguous resulting percept undergoes spontaneous fluctuations. stimulus can be rendered unambiguous addition binocular disparities. We trained monkeys to report these stimuli,...
Evolutionary adaptations of temporo-parietal cortex are considered to be a critical specialization the human brain. Cortical adaptations, however, can affect different aspects brain architecture, including local expansion cortical sheet or changes in connectivity between areas. We distinguish types architecture using computational neuroanatomy approach. investigate extent which between-species alignment, based on myelin, predict patterns across macaque, chimpanzee, and human. show that...
Diffusion-weighted magnetic resonance imaging (DW-MRI) tractography is a non-invasive tool to probe neural connections and the structure of white matter. It has been applied successfully in studies neurological disorders normal connectivity. Recent work revealed that produces high incidence false-positive connections, often from "bottleneck" matter configurations. The rich literature histological connectivity analysis macaque monkey enables quantitative evaluation performance algorithms. In...
The frontal lobe is central to distinctive aspects of human cognition and behavior. Some comparative studies link this a larger cortex even white matter in humans compared with other primates, yet others dispute these findings. discrepancies between could be explained by limitations the methods used quantify volume differences across species, especially when applied connections. In study, we novel tractography approach demonstrate that networks, extending within beyond lobes, occupy 66%...
Neurons in the extrastriate visual area V5/MT show perceptually relevant signals binocular depth tasks, which can be measured as a choice probability (CP) for neuron. The presence of CP particular paradigm may an indicator that neuron is generally part substrate perception depth. We compared responses those single neurons CPs one stereoscopic task with their another stereo task. Each was tested 1) during macaques responded to sign structure-from-motion stimulus, judge its direction...
Classic studies on social influence used simple perceptual decision-making tasks to examine how the opinions of others change individuals’ judgments. Since then, one most fundamental questions in psychology has been whether can alter basic processes. To address this issue, we a diffusion model analysis. Diffusion models provide stochastic approach for separating cognitive processes underlying speeded binary decisions. Following approach, our study is first disentangle decision making due...
Judgments of visual depth rely crucially on the relative binocular disparity between two features. While areas ventral cortex contain neurons that signal spatially adjacent features, same tests in dorsal yield little evidence for selectivity. We investigated sensitivity area V5/MT macaque monkeys to disparity, using superimposed, transparent planes composed dots moving opposite directions. The separation specifies their while absolute can be altered independently by changing with respect...
Effective perceptual decisions rely upon combining sensory information with knowledge of the rewards available for different choices. However, it is not known where reward signals interact multiple stages decision-making pathway and by what mechanisms this may occur. We combined electrical microstimulation functionally specific groups neurons in visual area V5/MT performance-contingent manipulation, while monkeys performed a discrimination task. Microstimulation was less effective shifting...
Judgments about the perceptual appearance of visual objects require combination multiple parameters, like location, direction, color, speed, and depth. Our understanding judgments has been greatly informed by studies ambiguous figures, which take on different appearances depending upon brain state observer. Here we probe neural mechanisms hypothesized as responsible for judging apparent direction rotation structure from motion (SFM) stimuli. Resolving SFM cylinders requires conjoint decoding...
Extrastriate visual area V5/MT in primates is defined both structurally by myeloarchitecture and functionally distinct responses to motion. Myelination directly identifiable from postmortem histology but also indirectly image contrast with structural magnetic resonance imaging (sMRI). First, we compared the identification of using sMRI Rhesus macaques. A section-by-section comparison histological slices vivo for same block cortical tissue showed precise correspondence localizing heavy...
Evaluation of the structural connectivity (SC) brain based on tractography has mainly focused choice diffusion model, algorithm, and their respective parameter settings. Here, we systematically validate SC derived from a post mortem monkey brain, while varying key acquisition parameters such as b-value, gradient angular resolution image resolution. As gold standard use matrix obtained invasively with histological tracers by Markov et al. (2014). performance metric, cross entropy measure that...
Significance Social influence biases even simple perceptual decisions across a range of contexts. The development and mechanism such remain unclear. We systematically examined the developmental course social bias exerted by another person on in children between 6 14 years old. To probe underlying mechanisms, we applied computational model drift diffusion to behavioral response data. Our results show that although young neurotypical seem be unaffected influence, adolescents develop systematic...
In studies of the developing mammalian visual system, it has been axiomatic that experience begins with eye-opening. Any role for neuronal activity earlier in development attributed to patterned spontaneous found retina and lateral geniculate nucleus (LGN). Here we show that, as early 2 wk before eye-opening, stimuli presented through closed eyelids can drive LGN striate cortex ferret. At this age, is much lower than LGN, responses many cortical, but not geniculate, neurons depend on...
In order to isolate the neuronal activity that relates making of perceptual decisions, we have made use a perceptually ambiguous motion stimulus. This stimulus lies on boundary between two categories correspond clockwise and counter–clockwise rotation three–dimensional figure. It consists two–dimensional pattern moving dots are capable generating these two, distinct, percepts. We studied responses neurons in cortical area V5/MT whilst macaque monkeys report judgements about configuration...
Autism spectrum disorder is a debilitating condition with possible neurodevelopmental origins but unknown neuroanatomical correlates. Whereas investigators have paid much attention to the cerebral cortex, few studies detailed basal ganglia in autism. The caudate nucleus may be involved repetitive movements and limbic changes of We used immunohistochemistry for calretinin neuropeptide Y 24 age- gender-matched patients autism control subjects ranging age from 13 69 years. Patients had 35%...
One of the most influential accounts central orbitofrontal cortex—that it mediates behavioral flexibility—has been challenged by finding that discrimination reversal in macaques, classic test flexibility, is unaffected when lesions are made excitotoxin injection rather than aspiration. This suggests critical brain circuit mediating flexibility tasks lies beyond cortex. To determine its identity, a group nine macaques were taught learning tasks, and impact on gray matter was measured....