The retrosplenial complex (RSC) plays a crucial role in spatial orientation by computing heading direction and translating between distinct spatial reference frames based on multi-sensory information. While invasive studies allow investigating heading computation in moving animals, established non-invasive analyses of human brain dynamics are restricted to stationary setups. To investigate the role of the RSC in heading computation of actively moving humans, we used a Mobile Brain/Body Imaging approach synchronizing electroencephalography with motion capture and virtual reality. Data from physically rotating participants were contrasted with rotations based only on visual flow. During physical rotation, varying rotation velocities were accompanied by pronounced wide frequency band synchronization in RSC, the parietal and occipital cortices. In contrast, the visual flow rotation condition was associated with pronounced alpha band desynchronization, replicating previous findings in desktop navigation studies, and notably absent during physical rotation. These results suggest an involvement of the human RSC in heading computation based on visual, vestibular, and proprioceptive input and implicate revisiting traditional findings of alpha desynchronization in areas of the navigation network during spatial orientation in movement-restricted participants.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8440696 | PMC |
http://dx.doi.org/10.1038/s41598-021-97749-8 | DOI Listing |
Biomolecules
December 2024
Department of Surgical Specialties, Radiological Sciences and Public Health, University of Brescia, 25123 Brescia, Italy.
Background: Brain calcifications, found in various conditions, may be incidental or crucial for diagnosis. They occur in physiological changes, infections, genetic diseases, neurodegenerative conditions, vascular syndromes, metabolic disorders, endocrine disorders, and primary tumors like oligodendroglioma. While often incidental, their presence can be vital for accurate diagnosis.
View Article and Find Full Text PDFMymensingh Med J
January 2025
Dr Md Azizul Hasan Khandaker, Acting Senior Specialist, Department of Cardiology, National Heart Center, Royal Hospital, Muscat, Sultanate of Oman; E-mail:
A 58-year-old hypertensive man was admitted with severe central chest pain and palpitation. His electrocardiogram (ECG) showed fast atrial fibrillation with features suggestive of left main coronary artery occlusion. He was taken to the Cath-lab but surprisingly, coronary angiogram (CAG) showed no stenosis.
View Article and Find Full Text PDFPLoS Comput Biol
December 2024
Department of Psychology, Philipps-Universität Marburg, Marburg, Hesse, Germany.
Accurate navigation often requires the maintenance of a robust internal estimate of heading relative to external surroundings. We present a model for angular velocity integration in a desert locust heading circuit, applying concepts from early theoretical work on heading circuits in mammals to a novel biological context in insects. In contrast to similar models proposed for the fruit fly, this circuit model uses a single 360° heading direction representation and is updated by neuromodulatory angular velocity inputs.
View Article and Find Full Text PDFNeural Netw
December 2024
State Key Lab of Brain-Machine Intelligence, Zhejiang University, China; College of Computer Science and Technology, Zhejiang University, China. Electronic address:
The spike-based neuronal responses within the ventral intraparietal area (VIP) exhibit intricate spatial and temporal dynamics in the posterior parietal cortex, presenting decoding challenges such as limited data availability at the biological population level. The practical difficulty in collecting VIP neuronal response data hinders the application of sophisticated decoding models. To address this challenge, we propose a unified spike-based decoding framework leveraging spiking neural networks (SNNs) for both generative and decoding purposes, for their energy efficiency and suitability for neural decoding tasks.
View Article and Find Full Text PDFSensors (Basel)
November 2024
Center for Computing Research, Sandia National Labs, Albuquerque, NM 87123, USA.
Accurate self-motion estimation is critical for various navigational tasks in mobile robotics. Optic flow provides a means to estimate self-motion using a camera sensor and is particularly valuable in GPS- and radio-denied environments. The present study investigates the influence of different activation functions-ReLU, leaky ReLU, GELU, and Mish-on the accuracy, robustness, and encoding properties of convolutional neural networks (CNNs) and multi-layer perceptrons (MLPs) trained to estimate self-motion from optic flow.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!