Strength of Suppression in Binocular Rivalry Immediately after Onset and Offset of Suppressing Pattern

1987 ◽  
Vol 65 (2) ◽  
pp. 515-523 ◽  
Author(s):  
Tamotsu Sohmiya ◽  
Kazuko Sohmiya
Keyword(s):  
Human Brain ◽  
Binocular Rivalry ◽  
Light Stimulus ◽  
Physiological Data ◽  
Temporal Properties ◽  
Dichoptic Viewing

If the dichoptic viewing method is used to analyze functions of the human brain rather than binocular rivalry itself, temporal properties of suppression come up as an important problem. To clarify the properties, a method in which test and suppressing patterns can be presented on any temporal condition was devised. When the suppressing pattern was flickered, the strength of suppression immediately after the onset of the pattern approached a maximum at the intercycle interval of 3 sec. It also increased with the increasing duration of exposure and reached a maximum at about 100 msec. The strength of suppression immediately after the offset decreased rapidly but continuously as time went on. These results indicate that the on-effect is produced by the presentation of the suppressing pattern, not the off-effect by its removal, whereas physiological data generally show the strong effect both at “on” and “off” of a light stimulus.

scholarly journals Single units and conscious vision

1998 ◽  
Vol 353 (1377) ◽  
pp. 1801-1818 ◽  
Author(s):  
◽  
N. K. Logothetis
Keyword(s):  
Binocular Rivalry ◽  
Neural Activity ◽  
Visual Awareness ◽  
Physiological Data ◽  
Neural Basis ◽  
Binocular Fusion ◽  
Neural Representations ◽  
Multistable Perception ◽  
Visual Areas ◽  
Psychophysical Studies

Figures that can be seen in more than one way are invaluable tools for the study of the neural basis of visual awareness, because such stimuli permit the dissociation of the neural responses that underlie what we perceive at any given time from those forming the sensory representation of a visual pattern. To study the former type of responses, monkeys were subjected to binocular rivalry, and the response of neurons in a number of different visual areas was studied while the animals reported their alternating percepts by pulling levers. Perception–related modulations of neural activity were found to occur to different extents in different cortical visual areas. The cells that were affected by suppression were almost exclusively binocular, and their proportion was found to increase in the higher processing stages of the visual system. The strongest correlations between neural activity and perception were observed in the visual areas of the temporal lobe. A strikingly large number of neurons in the early visual areas remained active during the perceptual suppression of the stimulus, a finding suggesting that conscious visual perception might be mediated by only a subset of the cells exhibiting stimulus selective responses. These physiological findings, together with a number of recent psychophysical studies, offer a new explanation of the phenomenon of binocular rivalry. Indeed, rivalry has long been considered to be closely linked with binocular fusion and stereopsis, and the sequences of dominance and suppression have been viewed as the result of competition between the two monocular channels. The physiological data presented here are incompatible with this interpretation. Rather than reflecting interocular competition, the rivalry is most probably between the two different central neural representations generated by the dichoptically presented stimuli. The mechanisms of rivalry are probably the same as, or very similar to, those underlying multistable perception in general, and further physiological studies might reveal a much about the neural mechanisms of our perceptual organization.

scholarly journals A causal study of bumetanide on a marker of excitatory-inhibitory balance in the human brain

2020 ◽  
Author(s):  
Thomas L. Botch ◽  
Alina Spiegel ◽  
Catherine Ricciardi ◽  
Caroline E. Robertson
Keyword(s):  
Human Brain ◽  
Binocular Rivalry ◽  
Response Times ◽  
Autism Spectrum ◽  
Autism Spectrum Conditions ◽  
Placebo Control ◽  
Acute Administration ◽  
Neural Processes ◽  
Within Subjects ◽  
The Brain

AbstractBumetanide has received much interest as a potential pharmacological modulator of the putative imbalance in excitatory/inhibitory (E/I) signaling that is thought to characterize autism spectrum conditions. Yet, currently, no studies of bumetanide efficacy have used an outcome measure that is modeled to depend on E/I balance in the brain. In this manuscript, we present the first causal study of the effect of bumetanide on an objective marker of E/I balance in the brain, binocular rivalry, which we have previously shown to be sensitive to pharmacological manipulation of GABA. Using a within-subjects placebo-control crossover design study, we show that, contrary to expectation, acute administration of bumetanide does not alter binocular rivalry dynamics in neurotypical adult individuals. Neither changes in response times nor response criteria can account for these results. These results raise important questions about the efficacy of acute bumetanide administration for altering E/I balance in the human brain, and highlight the importance of studies using objective markers of the underlying neural processes that drugs hope to target.

Does Interhemispheric Competition Mediate Motion-Induced Blindness? A Transcranial Magnetic Stimulation Study

Perception ◽  
10.1068/p5088 ◽  
2003 ◽  
Vol 32 (11) ◽  
pp. 1328-1338 ◽  
Author(s):  
Agnes P Funk ◽  
John D Pettigrew
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Binocular Rivalry ◽  
Magnetic Stimulation ◽  
Posterior Parietal Cortex ◽  
Right Hemisphere ◽  
Single Pulse ◽  
Underlying Mechanism ◽  
Temporal Properties ◽  
Interhemispheric Competition ◽  
Perceptual Rivalry

Motion-induced blindness (MIB) is a phenomenon, perhaps related to perceptual rivalry, where stationary targets disappear and reappear in a cyclic mode when viewed against a background (mask) of coherent, apparent 3-D motion. Since MIB has recently been shown to share similar temporal properties with binocular rivalry, we probed the appearance–disappearance cycle of MIB using unilateral, single-pulse transcranial magnetic stimulation (TMS)—a manipulation that has previously been shown to influence binocular rivalry. Effects were seen for both hemispheres when the timing of TMS was determined prospectively on the basis of a given subject's appearance–disappearance cycle, so that it occurred on average around 300 ms before the time of perceptual switch. Magnetic stimulation of either hemisphere shortened the time to switch from appearance to disappearance and vice versa. However, TMS of left posterior parietal cortex more selectively shortened the disappearance time of the targets if delivered in phase with the disappearance cycle, but lengthened it if TMS was delivered in the appearance phase after the perceptual switch. Opposite effects were seen in the right hemisphere, although less marked than the left-hemisphere effects. As well as sharing temporal characteristics with binocular rivalry, MIB therefore seems to share a similar underlying mechanism of interhemispheric modulation. Interhemispheric switching may thus provide a common temporal framework for uniting the diverse, multilevel phenomena of perceptual rivalry.

Effects of consciousness on human brain waves following binocular rivalry

Neuroreport ◽  
1999 ◽  
Vol 10 (4) ◽  
pp. 713-716 ◽  
Author(s):  
Christian Kaernbach ◽  
Erich Schröger ◽  
Thomas Jacobsen ◽  
Urte Roeber
Keyword(s):  
Human Brain ◽  
Binocular Rivalry ◽  
Brain Waves

scholarly journals A binocular rivalry study of motion perception in the human brain

2005 ◽  
Vol 45 (17) ◽  
pp. 2231-2243 ◽  
Author(s):  
K. Moutoussis ◽  
G. Keliris ◽  
Z. Kourtzi ◽  
N. Logothetis
Keyword(s):  
Human Brain ◽  
Motion Perception ◽  
Binocular Rivalry

Energy Harvesting From Arterial Blood Pressure for Powering Embedded Microsensors in Human Brain

2017 ◽  
Author(s):  
Aditya Nanda ◽  
M. Amin Karami
Keyword(s):  
Blood Pressure ◽  
Energy Harvesting ◽  
Carotid Artery ◽  
Human Brain ◽  
Arterial Blood Pressure ◽  
Arterial Wall ◽  
Physiological Data ◽  
Induced Voltage ◽  
Arterial Blood

This manuscript investigates energy harvesting from arterial blood pressure via the piezoelectric effect for the purpose of powering embedded micro-sensors in the human brain. One of the major hurdles in recording and measuring electrical data in the human nervous system is the lack of implantable and long term interfaces that record neural activity for extended periods of time. Recently, some authors have proposed micro sensors implanted deep in the brain that measure local electrical and physiological data which is then communicated to an external interrogator. This paper proposes a way of powering such interfaces. The geometry of the proposed harvester consists of a piezoelectric, circular, curved bimorph that fits into the blood vessel (specifically, the Carotid artery) and undergoes bending motion because of blood pressure variation. In addition, the harvester thickness is constrained such that it does not modify arterial wall dynamics. This transforms the problem into a known strain problem and the integral form of Gauss’s law is used to obtain an equation relating arterial wall motion to the induced voltage. The theoretical model is validated by means of a Multiphysics 3D-FEA simulation comparing the harvested power at different load resistances. The peak harvested power achieved for the Carotid artery (proximal to Brain), with PZT-5H, was 11.7 μ W. The peak power for the Aorta was 203.4 μ W. Further, the variation of harvested power with variation in harvester width and thickness, arterial contractility and the pulse rate is investigated. Moreover, potential application of the harvester as a chronic, implantable and real-time Blood pressure sensor is considered. Energy harvested via this mechanism will also have applications in long-term, implantable Brain Micro-stimulation.

scholarly journals Mathematical modeling of human brain physiological data

2013 ◽  
Vol 88 (6) ◽  
Author(s):  
Matthias Böhm ◽  
Rupert Faltermeier ◽  
Alexander Brawanski ◽  
Elmar W. Lang
Keyword(s):  
Mathematical Modeling ◽  
Human Brain ◽  
Physiological Data

scholarly journals Interpretable multi-timescale models for predicting fMRI responses to continuous natural speech

2020 ◽  
Author(s):  
Shailee Jain ◽  
Vy A. Vo ◽  
Shivangi Mahto ◽  
Amanda LeBel ◽  
Javier S. Turek ◽  
...  
Keyword(s):  
Neural Network ◽  
Natural Language ◽  
Human Brain ◽  
Language Models ◽  
Natural Speech ◽  
Human Language ◽  
Multiple Timescales ◽  
Temporal Properties ◽  
Network Language ◽  
Future Work

AbstractNatural language contains information at multiple timescales. To understand how the human brain represents this information, one approach is to build encoding models that predict fMRI responses to natural language using representations extracted from neural network language models (LMs). However, these LM-derived representations do not explicitly separate information at different timescales, making it difficult to interpret the encoding models. In this work we construct interpretable multi-timescale representations by forcing individual units in an LSTM LM to integrate information over specific temporal scales. This allows us to explicitly and directly map the timescale of information encoded by each individual fMRI voxel. Further, the standard fMRI encoding procedure does not account for varying temporal properties in the encoding features. We modify the procedure so that it can capture both short- and long-timescale information. This approach outper-forms other encoding models, particularly for voxels that represent long-timescale information. It also provides a finer-grained map of timescale information in the human language pathway. This serves as a framework for future work investigating temporal hierarchies across artificial and biological language systems.

Afterimages, Binocular Rivalry, and the Temporal Properties of Dominance and Suppression

Perception ◽  
1983 ◽  
Vol 12 (4) ◽  
pp. 439-445 ◽  
Author(s):  
Jeremy M Wolfe
Keyword(s):  
Binocular Rivalry ◽  
Present Experiment ◽  
Checkerboard Pattern ◽  
Intermittent Stimulation ◽  
Temporal Properties

When different contours are presented to the two eyes, an unstable percept, binocular rivalry, is the result. Parts of each set of contours may be seen but the two sets are not seen in the same place at the same time. The contours need not be physically present. Afterimages will produce binocular rivalry. Normal rivalry can be prevented if intermittent stimulation is used. Previous work has shown that orthogonal gratings, flashed for less than 150 ms and separated by more than 150 ms, will appear to fuse into a plaid or checkerboard pattern. In the present experiment this phenomenon is examined with afterimages used to produce rivalry. This abnormal ‘fusion’ is seen when negative afterimages are stroboscopically illuminated at less than 5 Hz. The results obtained with afterimages are predictable from the previous results obtained with stimuli external to the eye.

Sign in / Sign up

Export Citation Format

Share Document