We have measured magnetic fields evoked by the onset of checkerboard-like sectorial patterns presented at 16 locations near the center of the visual field. Small stimuli (less than 2 degrees), which, nevertheless, gave sufficiently strong responses to enable source localization, were used to limit cortical activation to a small area, thus simplifying the analysis of the magnetic field data. We focused on optimizing the experimental design: cortical sources could be located from measurements at just one position of our 24-channel magnetometer and with as few as 15-20 repetitions of the stimulus. Minimum-norm-estimate maps calculated from even a single response showed reproducible features of the current distribution, which was, 80-100 msec after the pattern onset, retinotopically organized in the occipital lobe. Since magnetoencephalography can reveal cortical locations with a precision of 2-3 mm, our procedure appears promising for further studies of cortical retinotopy and visual field defects.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/0013-4694(92)90172-e | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Triterpenoid saponin-mediated recovery of visual deficits in age-related macular degeneration (AMD): Double-blind, placebo-controlled, randomised clinical trial.
Asia Pac J Ophthalmol (Phila)
January 2025
Rescue, Repair and Regeneration Theme, UCL Institute of Ophthalmology, London, United Kingdom. Electronic address:
Purpose: Recovery rate of rod photoreceptor sensitivity (S2 gradient) following a bleach is reduced in age-related macular degeneration (AMD) due to diminished delivery of retinol across a grossly altered Bruch's membrane. Since triterpenoid saponins are known to improve transport across Bruch's, we have assessed their possible use for reversing the visual deficits in AMD.
Design: Double-blind, placebo controlled randomised clinical trial.
Luminance invariant encoding in mouse primary visual cortex.
Cell Rep
January 2025
Center for Perceptual Systems, The University of Texas at Austin, Austin, TX 78712, USA; Center for Learning and Memory, The University of Texas at Austin, Austin, TX 78712, USA; Department of Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA. Electronic address:
The visual system adapts to maintain sensitivity and selectivity over a large range of luminance intensities. One way that the retina maintains sensitivity across night and day is by switching between rod and cone photoreceptors, which alters the receptive fields and interneuronal correlations of retinal ganglion cells (RGCs). While these adaptations allow the retina to transmit visual information to the brain across environmental conditions, the code used for that transmission varies.
View Article and Find Full Text PDFGlobal Publication Trends and Research Hotspots of Diabetes and Osteoporosis.
Endocr Metab Immune Disord Drug Targets
January 2025
Department of Rheumatology and Immunology, The First Affiliated Hospital of Army Medical University, Chongqing, China.
Background: Diabetes and osteoporosis, as chronic diseases with high incidence, have caused deep concern in the field of global public health due to their high morbidity and mortality. More importantly, the complex and close relationship between diabetes and osteoporosis has gradually become the focus of scientific research. It is very meaningful to carry out bibliometric analysis in the research field of diabetes and osteoporosis to describe the current international trend and present a visual representation of the past and emerging trends of diabetes and osteoporosis in the past decade.
View Article and Find Full Text PDFUbiquitination in diabetes and its complications: A perspective from bibliometrics.
World J Diabetes
January 2025
College of Traditional Chinese Medicine, Anhui University of Chinese Medicine, Hefei 230012, Anhui Province, China.
Background: Diabetes has a substantial impact on public health, highlighting the need for novel treatments. Ubiquitination, an intracellular protein modification process, is emerging as a promising strategy for regulating pathological mechanisms. We hypothesize that ubiquitination plays a critical role in the development and progression of diabetes and its complications, and that understanding these mechanisms can lead to new therapeutic approaches.
View Article and Find Full Text PDFArthroscopy is a minimally invasive surgical procedure used to diagnose and treat joint problems. The clinical workflow of arthroscopy typically involves inserting an arthroscope into the joint through a small incision, during which surgeons navigate and operate largely by relying on their visual assessment through the arthroscope. However, the arthroscope's restricted field of view and lack of depth perception pose challenges in navigating complex articular structures and achieving surgical precision during procedures.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!