Activity in early visual areas predicts interindividual differences in binocular rivalry dynamics

When dissimilar images are presented to the two eyes, binocular rivalry (BR) occurs, and perception alternates spontaneously between the images. Although neural correlates of the oscillating perception during BR have been found in multiple sites along the visual pathway, the source of BR dynamics is unclear. Psychophysical and modeling studies suggest that both low- and high-level cortical processes underlie BR dynamics. Previous neuroimaging studies have demonstrated the involvement of high-level regions by showing that frontal and parietal cortices responded time locked to spontaneous perceptual alternation in BR. However, a potential contribution of early visual areas to BR dynamics has been overlooked, because these areas also responded to the physical stimulus alternation mimicking BR. In the present study, instead of focusing on activity during perceptual switches, we highlighted brain activity during suppression periods to investigate a potential link between activity in human early visual areas and BR dynamics. We used a strong interocular suppression paradigm called continuous flash suppression to suppress and fluctuate the visibility of a probe stimulus and measured retinotopic responses to the onset of the invisible probe using functional MRI. There were ∼130-fold differences in the median suppression durations across 12 subjects. The individual differences in suppression durations could be predicted by the amplitudes of the retinotopic activity in extrastriate visual areas (V3 and V4v) evoked by the invisible probe. Weaker responses were associated with longer suppression durations. These results demonstrate that retinotopic representations in early visual areas play a role in the dynamics of perceptual alternations during BR.

Download Full-text

Alterations of Regional Spontaneous Brain Activity and Gray Matter Volume in the Blind

Neural Plasticity ◽

10.1155/2015/141950 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 10

Author(s):

Aili Jiang ◽

Jing Tian ◽

Rui Li ◽

Yong Liu ◽

Tianzi Jiang ◽

...

Keyword(s):

Gray Matter ◽

Brain Activity ◽

Gray Matter Volume ◽

Brain Regions ◽

Visual Deprivation ◽

Onset Age ◽

Spontaneous Brain Activity ◽

Matter Volume ◽

Visual Areas ◽

High Level

Visual deprivation can induce alterations of regional spontaneous brain activity (RSBA). However, the effects of onset age of blindness on the RSBA and the association between the alterations of RSBA and brain structure are still unclear in the blind. In this study, we performed resting-state functional and structural magnetic resonance imaging on 50 sighted controls and 91 blind subjects (20 congenitally blind, 27 early blind, and 44 late blind individuals). Compared with the sighted control, we identified increased RSBA in the blind in primary and high-level visual areas and decreased RSBA in brain regions which are ascribed to sensorimotor and salience networks. In contrast, blind subjects exhibited significantly decreased gray matter volume (GMV) in the visual areas, while they exhibited significantly increased GMV in the sensorimotor areas. Moreover, the onset age of blindness was negatively correlated with the GMV of visual areas in blind subjects, whereas it exerted complex influences on the RSBA. Finally, significant negative correlations were shown between RSBA and GMV values. Our results demonstrated system-dependent, inverse alterations in RSBA and GMV after visual deprivation. Furthermore, the onset age of blindness has different effects on the reorganizations in RSBA and GMV.

Download Full-text

Differentiation Analysis of Continuous Electroencephalographic Activity Triggered by Video Clip Contents

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01278 ◽

2018 ◽

Vol 30 (8) ◽

pp. 1108-1118 ◽

Cited By ~ 2

Author(s):

Armand Mensen ◽

William Marshall ◽

Shuntaro Sasai ◽

Giulio Tononi

Keyword(s):

Brain Activity ◽

Random Noise ◽

Video Clip ◽

Individual Level ◽

Spectral Bands ◽

Short Video ◽

Brain States ◽

The Individual ◽

High Level ◽

Electroencephalographic Activity

While viewing a video clip, we experience a wide variety of contents, from low-level features of the images to high-level ideas such as the storyline. Each change in our experience must be supported by some corresponding change in neurophysiological activity. Differentiation analysis, which quantifies the differences in brain activity by measuring the distances between observed brain states, was applied here to continuous high-density electroencephalographic data recorded while participants watched short video clips. These clips were manipulated in various ways to change the degree of meaningfulness of their contents. We found that neurophysiological differentiation mirrored that of phenomenal differentiation, being higher for meaningful clips and lower for phase-scrambled versions or random noise. The distinction between meaningful and meaningless clips was present even at the individual level, and moreover, differentiation values correlated with individual subjective reports of meaningfulness. Spatial and spectral breakdowns of the overall effect showed frontal and posterior ROIs and highlighted specific roles for different spectral bands. Comparing the results with a multivariate decoding approach reveals that the two methods are capturing different aspects of brain activity and highlights a crucial theoretical distinction between the level and pattern of activity. In future applications, differentiation analysis may be used to evaluate the subjective meaningfulness of stimuli when behavioral responses may be inadequate, as with disorders of consciousness.

Download Full-text

Human brain activity during mental imagery exhibits signatures of inference in a hierarchical generative model

10.1101/462226 ◽

2018 ◽

Author(s):

Jesse Breedlove ◽

Ghislain St-Yves ◽

Cheryl Olman ◽

Thomas Naselaris

Keyword(s):

Mental Imagery ◽

Human Subjects ◽

Brain Activity ◽

Generative Model ◽

Formal Structure ◽

Low Level ◽

Visual Encoding ◽

Visual Areas ◽

High Level ◽

Echo Effect

Humans have long wondered about the function of mental imagery and its relationship to vision. Although visual representations are utilized during imagery, the computations they subserve are unclear. Building on a theory that treats vision as inference about the causes of sensory stimulation in an internal generative model, we propose that mental imagery is inference about the sensory consequences of predicted or remembered causes. The relation between these complementary inferences yields a relation between the brain activity patterns associated with imagery and vision. We show that this relation has the formal structure of an echo that makes encoding of imagined stimuli in low-level visual areas resemble the encoding of seen stimuli in higher areas. To test for evidence of this echo effect we developed imagery encoding models—a new tool for revealing how imagined stimuli are encoded in brain activity. We estimated imagery encoding models from brain activity measured with fMRI while human subjects imagined complex visual stimuli, and then compared these to visual encoding models estimated from a matched viewing experiment. Consistent with an echo effect, imagery encoding models in low-level visual areas exhibited decreased spatial frequency preference and larger, more foveal receptive fields, thus resembling visual encoding models in high-level visual areas where imagery and vision appeared to be almost interchangeable. Our findings support an interpretation of mental imagery as a predictive inference that is conditioned on activity in high-level visual cortex, and is related to vision through shared dependence on an internal model of the visual world.

Download Full-text

A Neural Basis for Percept Stabilization in Binocular Rivalry

Journal of Cognitive Neuroscience ◽

10.1162/jocn.2008.20039 ◽

2008 ◽

Vol 20 (3) ◽

pp. 389-399 ◽

Cited By ~ 59

Author(s):

Philipp Sterzer ◽

Geraint Rees

Keyword(s):

Binocular Rivalry ◽

Brain Activity ◽

Delay Period ◽

Behavioral Experiment ◽

Conscious Perception ◽

Neural Basis ◽

Bistable Perception ◽

Face Area ◽

Human Participants ◽

High Level

When the same visual input has conflicting interpretations, conscious perception can alternate spontaneously between each competing percept. Surprisingly, such bistable perception can be stabilized by intermittent stimulus removal, suggesting the existence of perceptual “memory” across interruptions in stimulation. The neural basis of such a process remains unknown. Here, we studied binocular rivalry, one type of bistable perception, in two linked experiments in human participants. First, we showed, in a behavioral experiment using binocular rivalry between face and grating stimuli, that the stabilizing effect of stimulus removal was specific to perceptual alternations evoked by rivalry, and did not occur following physical alternations in the absence of rivalry. We then used functional magnetic resonance imaging to measure brain activity in a variable delay period of stimulus removal. Activity in the fusiform face area during the delay period following removal of rivalrous stimuli was greater following face than grating perception, whereas such a difference was absent during removal of non-rivalrous stimuli. Moreover, activity in areas of fronto-parietal regions during the delay period correlated with the degree to which individual participants tended to experience percept stabilization. Our findings suggest that percept-related activity in specialized extrastriate visual areas help to stabilize perception during perceptual conflict, and that high-level mechanisms may determine the influence of such signals on conscious perception.

Download Full-text

Bottom-up and top-down influences at untrained conditions determine perceptual learning specificity and transfer

eLife ◽

10.7554/elife.14614 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 8

Author(s):

Ying-Zi Xiong ◽

Jun-Yun Zhang ◽

Cong Yu

Keyword(s):

Perceptual Learning ◽

Top Down ◽

Transfer Condition ◽

Bottom Up ◽

Visual Neurons ◽

Continuous Flash Suppression ◽

Visual Areas ◽

Suppression Technique ◽

High Level ◽

Additional Exposure

Perceptual learning is often orientation and location specific, which may indicate neuronal plasticity in early visual areas. However, learning specificity diminishes with additional exposure of the transfer orientation or location via irrelevant tasks, suggesting that the specificity is related to untrained conditions, likely because neurons representing untrained conditions are neither bottom-up stimulated nor top-down attended during training. To demonstrate these top-down and bottom-up contributions, we applied a “continuous flash suppression” technique to suppress the exposure stimulus into sub-consciousness, and with additional manipulations to achieve pure bottom-up stimulation or top-down attention with the transfer condition. We found that either bottom-up or top-down influences enabled significant transfer of orientation and Vernier discrimination learning. These results suggest that learning specificity may result from under-activations of untrained visual neurons due to insufficient bottom-up stimulation and/or top-down attention during training. High-level perceptual learning thus may not functionally connect to these neurons for learning transfer.

Download Full-text

Alpha fluctuations regulate the accrual of visual information to awareness

10.1101/2020.09.16.298166 ◽

2020 ◽

Author(s):

Mireia Torralba ◽

Alice Drew ◽

Alba Sabaté San José ◽

Luis Morís Fernández ◽

Salvador Soto-Faraco

Keyword(s):

Binocular Rivalry ◽

Visual Information ◽

Brain Activity ◽

Visual Awareness ◽

Sensory Information ◽

Occipital Cortex ◽

Visual Inputs ◽

Perceptual Alternation ◽

Eeg Recordings ◽

The Individual

AbstractEndogenous brain processes play a paramount role in shaping up perceptual phenomenology, as illustrated by the alternations experienced by humans (and other animals) when watching perceptually ambiguous, static images. Here, we hypothesised that endogenous alpha fluctuations in the visual cortex pace the accumulation of sensory information leading to perceptual outcomes. We addressed this hypothesis using binocular rivalry combined with visual entrainment and electroencephalography in humans (42 female, 40 male). The results revealed a correlation between the individual frequency of alpha oscillations in the occipital cortex and perceptual alternation rates experienced during binocular rivalry. In subsequent experiments we show that regulating endogenous brain activity via entrainment produced corresponding changes in perceptual alternation rate, which were observed only in the alpha range but not at lower entrainment frequencies. Overall, rhythmic alpha stimulation resulted in faster perceptual alternation rates, compared to arrhythmic or no stimulation. These findings support the notion that visual information is accumulated via alpha cycles to promote the emergence of conscious perceptual representations. We suggest that models of binocular rivalry incorporating posterior alpha as a pacemaker can provide an important advance in the comprehension of the dynamics of visual awareness.Significance statementMainstream theories in cognitive neuroscience agree that endogenous brain processes play a paramount role in shaping our perceptual experience of sensory inputs. In vision, endogenous fluctuations in the alpha rhythm have been pointed out to regulate visual inputs to perception. In support of this hypothesis, here we used EEG recordings and visual entrainment to demonstrate that inter-individual differences in the speed of endogenous alpha fluctuations in the brain are causally related to the accrual of visual information to awareness. These findings provide, for the first time, evidence for alpha-gated regulation of the dynamics of alternations in conscious visual perception.

Download Full-text

Peripheral Levels of the Micro-RNA MiR-1202 are Correlated with Changes in Brain Activity and Connectivity During an Antidepressant Treatment

European Psychiatry ◽

10.1016/j.eurpsy.2017.01.2053 ◽

2017 ◽

Vol 41 (S1) ◽

pp. S167-S167

Author(s):

J.P. Lopez ◽

F. Pereira ◽

S. Richard-Devantoy ◽

Y. Ding ◽

L.M. Fiori ◽

...

Keyword(s):

Antidepressant Treatment ◽

Brain Activity ◽

Rna Extraction ◽

Micro Rna ◽

Posterior Cingulate ◽

Micro Rnas ◽

Potential Link ◽

Secondary Analyses ◽

Parietal Cortices

IntroductionMicro-RNAs are short non-coding sequences playing a major role in regulating gene expression. Peripheral levels of the micro-RNA miR-1202 have been shown to predict antidepressant response and to change during treatment. However, it is not clear to what extent these peripheral measures reflect central neural changes in vivo.ObjectivesWe aimed at investigating a potential link between peripheral micro-RNA and neuroimaging measures.MethodsAt baseline and after 8 weeks of desvenlafaxine (50–100 mg die), twenty depressed patients were scanned with 3 T magnetic resonance imaging, first at rest then during the Go/NoGo task, a classical test of response inhibition. Blood samples were taken for RNA extraction.ResultsDuring resting state, baseline miR-1202 levels were predictive of decreased connectivity between the posterior cingulate and the prefrontal, occipital and parietal cortices. Changes in miR-1202 levels were correlated with changes in activity in right precuneus within the default-mode network, and with decreased connectivity between the posterior cingulate and the temporal and prefrontal cortices, and the precuneus. During the Go/NoGo task, baseline levels and changes in these levels were correlated with activity changes in different regions, including bilateral prefrontal, insular, cingulate, and temporal cortices. Finally, secondary analyses suggest an association between miR-1202 levels and glutamate levels measured by spectroscopy in dorsomedial prefrontal cortex.ConclusionsThis is the first study showing that baseline and changes in peripheral levels of one micro-RNA were associated with changes in brain activity and connectivity during an antidepressant treatment. MiR-1202 may act through the modulation of the glutamatergic system.

Download Full-text

No impact of affective person knowledge on visual awareness: Evidence from binocular rivalry and continuous flash suppression.

Emotion ◽

10.1037/emo0000305 ◽

2017 ◽

Vol 17 (8) ◽

pp. 1199-1207 ◽

Cited By ~ 6

Author(s):

Timo Stein ◽

Caitlyn Grubb ◽

Maria Bertrand ◽

Seh Min Suh ◽

Sara C. Verosky

Keyword(s):

Binocular Rivalry ◽

Visual Awareness ◽

Continuous Flash Suppression

Download Full-text

Territorial Distribution of Alcohol and Drug Addictions Mortality Concerning Regional Disparities in the Slovak Republic from Year 1996 to Year 2015

10.35198/01-2019-003-0005 ◽

2020 ◽

Keyword(s):

Mortality Rate ◽

Slovak Republic ◽

Regional Disparities ◽

Point Of View ◽

Extreme Position ◽

Data Set ◽

Female Sex ◽

Male Sex ◽

The Individual ◽

High Level

BACKGROUND: This paper deals with territorial distribution of the alcohol and drug addictions mortality at a level of the districts of the Slovak Republic. AIM: The aim of the paper is to explore the relations within the administrative territorial division of the Slovak Republic, that is, between the individual districts and hence, to reveal possibly hidden relation in alcohol and drug mortality. METHODS: The analysis is divided and executed into the two fragments – one belongs to the female sex, the other one belongs to the male sex. The standardised mortality rate is computed according to a sequence of the mathematical relations. The Euclidean distance is employed to compute the similarity within each pair of a whole data set. The cluster analysis examines is performed. The clusters are created by means of the mutual distances of the districts. The data is collected from the database of the Statistical Office of the Slovak Republic for all the districts of the Slovak Republic. The covered time span begins in the year 1996 and ends in the year 2015. RESULTS: The most substantial point is that the Slovak Republic possesses the regional disparities in a field of mortality expressed by the standardised mortality rate computed particularly for the diagnoses assigned to the alcohol and drug addictions at a considerably high level. However, the female sex and the male sex have the different outcome. The Bratislava III District keeps absolutely the most extreme position. It forms an own cluster for the both sexes too. The Topoľčany District bears a similar extreme position from a point of view of the male sex. All the Bratislava districts keep their mutual notable dissimilarity. Contrariwise, evaluation of a development of the regional disparities among the districts looks like notably heterogeneously. CONCLUSIONS: There are considerable regional discrepancies throughout the districts of the Slovak Republic. Hence, it is necessary to create a common platform how to proceed with the solution of this issue.

Download Full-text

Quantitative indicators of air traffic controllers’ attitude to the danger of errors

Science, technologies, innovation ◽

10.35668/2520-6524-2020-4-07 ◽

2020 ◽

pp. 68-78

Author(s):

O. M. Reva ◽

V. V. Kamyshin ◽

S. P. Borsuk ◽

V. A. Shulhin ◽

A. V. Nevynitsyn

Keyword(s):

Human Factor ◽

Differential Method ◽

Air Traffic ◽

Professional Activity ◽

Aviation Accidents ◽

Air Traffic Controllers ◽

The Difference ◽

Level Of Significance ◽

The Individual ◽

High Level

The negative and persistent impact of the human factor on the statistics of aviation accidents and serious incidents makes proactive studies of the attitude of “front line” aviation operators (air traffic controllers, flight crewmembers) to dangerous actions or professional conditions as a key component of the current paradigm of ICAO safety concept. This “attitude” is determined through the indicators of the influence of the human factor on decision-making, which also include the systems of preferences of air traffic controllers on the indicators and characteristics of professional activity, illustrating both the individual perception of potential risks and dangers, and the peculiarities of generalized group thinking that have developed in a particular society. Preference systems are an ordered (ranked) series of n = 21 errors: from the most dangerous to the least dangerous and characterize only the danger preference of one error over another. The degree of this preference is determined only by the difference in the ranks of the errors and does not answer the question of how much time one error is more dangerous in relation to another. The differential method for identifying the comparative danger of errors, as well as the multistep technology for identifying and filtering out marginal opinions were applied. From the initial sample of m = 37 professional air traffic controllers, two subgroups mB=20 and mG=7 people were identified with statisti-cally significant at a high level of significance within the group consistency of opinions a = 1%. Nonpara-metric optimization of the corresponding group preference systems resulted in Kemeny’s medians, in which the related (middle) ranks were missing. Based on these medians, weighted coefficients of error hazards were determined by the mathematical prioritization method. It is substantiated that with the ac-cepted accuracy of calculations, the results obtained at the second iteration of this method are more ac-ceptable. The values of the error hazard coefficients, together with their ranks established in the preference systems, allow a more complete quantitative and qualitative analysis of the attitude of both individual air traffic controllers and their professional groups to hazardous actions or conditions.

Download Full-text