A5010560278- Neural dynamics and brain function
- Visual perception and processing mechanisms
- Neuroscience and Neural Engineering
- ECG Monitoring and Analysis
- Non-Invasive Vital Sign Monitoring
- Conducting polymers and applications
- CCD and CMOS Imaging Sensors
- Face Recognition and Perception
- Phonocardiography and Auscultation Techniques
- Neural Networks and Applications
- Advanced Fluorescence Microscopy Techniques
- Natural Language Processing Techniques
- Neurobiology and Insect Physiology Research
- Electrochemical sensors and biosensors
- EEG and Brain-Computer Interfaces
- Topic Modeling
- Photoreceptor and optogenetics research
- Advanced Memory and Neural Computing
- Nutritional Studies and Diet
- Robotics and Automated Systems
- Advanced Vision and Imaging
- Retinal Development and Disorders
- Primate Behavior and Ecology
- Receptor Mechanisms and Signaling
Australian College of Optometry
2017-2024
Vision Australia
2021-2024
Sharif University of Technology
2011-2013
University of Szeged
2009
Extracellular spikes recorded in the visual cortex (Area 17/18, V1) are commonly classified into either regular-spiking (RS) or fast-spiking (FS). Using multi-electrode arrays positioned cat V1 and a broadband stimulus, we show that there is also distinct class with positive-spiking (PS) waveforms. PS units were associated mainly non-oriented receptive fields while RS FS had orientation-selective fields. We suggest recordings of axons originating from thalamus. This conclusion was reinforced...
This work was produced as part of the activities FAPESP Research, Disseminations and Innovation Center for Neuromathematics (grant 2013/07699-0, S. Paulo Research Foundation). NLK is supported by a FAPESP postdoctoral fellowship (grant 2016/03855-5). ACR partially supported a CNPq 306251/2014-0).
Visual object identification requires both selectivity for specific visual features that are important to the object's identity and invariance feature manipulations. For example, a hand can be shifted in position, rotated, or contracted but still recognized as hand. How competing requirements of built into early stages processing? Typically, cells primary cortex classified either simple complex. They show edge-orientation complex develop edge position within receptive field (spatial phase)....
OBJECTIVE In this study the authors describe system submitted by team of University Szeged to second i2b2 Challenge in Natural Language Processing for Clinical Data. The challenge focused on development automatic systems that analyzed clinical discharge summary texts and addressed following question: "Who's obese what co-morbidities do they (definitely/most likely) have?". Target diseases included obesity its 15 most frequent comorbidities exhibited patients, while target labels corresponded...
In this paper we introduce a dynamical model for Phonocardiogram (PCG) signal which is capable of generating realistic synthetic PCG signals. This based on morphology and consists three ordinary differential equations can represent various morphologies normal Beat-to-beat variation in significant so parameters vary from beat to beat. inspired Electrocardiogram (ECG) proposed by McSharry et al. be employed assess biomedical processing techniques.
Abstract Implantable electrodes that can communicate with a small, selective group of neurons via both neural stimulation and recording are critical for the development advanced neuroprosthetic devices. Microfiber neuron‐scale cross‐sections have potential to improve spatial resolution recording, while minimizing chronic inflammation response after implantation. In this work, glass insulated microfiber fabricated by coating carbon fibers boron‐doped nanowalls. The significantly improves...
There are two distinct classes of cells in the primary visual cortex (V1): simple and complex cells. One defining feature is their spatial phase invariance; they respond strongly to oriented grating stimuli with a preferred orientation but wide range phases. A classical model complete invariance energy model, which responses sum squared outputs linear spatially phase-shifted filters. However, recent experimental studies have shown that diverse only subset can be characterized by model. While...
Primary visual cortices in many mammalian species exhibit modular and periodic orientation preference maps arranged pinwheel-like layouts. The role of inherited traits as opposed to environmental influences determining this organization remains unclear. Here, we characterize the cortical an Australian marsupial, revealing pinwheel resembling that eutherian carnivores primates but distinctly different from simpler salt-and-pepper arrangement rodents rabbits. divergence marsupials eutherians...
We studied the changes that neuronal receptive field (RF) models undergo when statistics of stimulus are changed from those white Gaussian noise (WGN) to natural scenes (NSs), by fitting multielectrode data recorded primary visual cortex (V1) female cats. This allowed estimation both a cascade linear filters on stimulus, as well static nonlinearities map output spike rates. found cells respond differently these two classes stimuli, with mostly higher rates and shorter response latencies NSs...
Abstract There are two distinct classes of cells in the primary visual cortex (V1): simple and complex cells. One defining feature is their spatial phase invariance; they respond strongly to oriented grating stimuli with a preferred orientation but wide range phases. A classical model complete invariance energy model, which responses sum squared outputs linear spatially phase-shifted filters. However, recent experimental studies have shown that diverse only subset can be characterized by...
: Neurons in primary visual cortex (V1) display a range of sensitivity their response to translations preferred features within receptive field: from high specificity precise position through complete invariance. This feature selectivity and invariance is frequently modeled by applying selection linear spatial filters the input image, that define selectivity, followed nonlinear function combines filter outputs, defines invariance, predict neural response. We compare two such classes model,...
Abstract A fundamental question in sensory neuroscience revolves around how neurons represent complex visual stimuli. In mammalian primary cortex (V1), decode intricate features to identify objects, with most being selective for edge orientation, but half of those also developing invariance position within their receptive fields. Position allows cells continue code an even when it moves around. Combining feature selectivity and is integral successful object recognition. Considering the...
Precise mathematical modeling of the primary visual cortex (V1) is still a challenging problem. Due to high similarity system cat and human, in this paper, we present hybrid model track electrical responses neurons that are measured by multi-electrode array implanted V1. The proposed combines stochastic phenomenological with multilayer leaky integrate-and-fire (LIF) predict V1 responses. Since all existing models do not capture properties synaptic changes, provides input currents for...
Electrocardiogram is one of the most prominent cardiac signals being capable to be utilized for medical uses such as arrhythmia detection. Over years, feasibility using this signal human identification issue has been investigated, and some methods have proposed. In Paper a novel approach proposed electrocardiogram (ECG) based Extended Kalman Filter (EKF). The innovation EKF considered feature which used classify different subjects. paper general issue, identification, summarized...
Abstract Visual object identification requires both selectivity for specific visual features that are important to the object’s identity and invariance feature manipulations. For example, a hand can be shifted in position, rotated, or contracted but still recognised as hand. How competing requirements of built into early stages processing? Typically, cells primary cortex classified either simple complex. They show edge-orientation complex develop edge position within receptive field (spatial...
The authors have withdrawn their manuscript due to a duplicate posting on our website. Please visit doi.org/10.1101/2020.05.18.101881 access the current version of this preprint bioRxiv
Abstract We studied the changes that neuronal RF models undergo when statistics of stimulus are changed from those white Gaussian noise (WGN) to natural scenes (NS). Fitting model data estimates both a cascade linear filters on stimulus, as wells static nonlinearities map output spike rates. found cells respond differently these two classes stimuli, with mostly higher rates and shorter response latencies NS than WGN. The most striking finding was resulted in RFs had additional uncovered did...