• Learning speed and detection sensitivity controlled by distinct cortico-fugal neurons in visual cortex. (ucsf.edu)
  • Feedback generates a second receptive field in neurons of the visual cortex. (ucsf.edu)
  • In anticipation of each saccade, many neurons in the visual system shift their receptive fields. (duke.edu)
  • Our eyes capture visual stimuli which are converted into an image, to which the brain responds by organizing neurons into clusters. (kyoto-u.ac.jp)
  • He adds that his results, however, suggest the clustering of neurons in the superior colliculus changes in response to the condition of the brain to process visual information efficiently. (kyoto-u.ac.jp)
  • A conventional visual fixation paradigm was used as a control task, to assess location and extent of visual receptive field of neurons. (nih.gov)
  • Neurons in the premotor cortex are also selectively activated before a movement starts. (wewantscience.com)
  • The mirror neurons discharged differently in the motor and visual conditions (Figure 3) when the monkey was executing grasping-to-eat or grasping-to-place actions (action-goal-related mirror neurons). (wewantscience.com)
  • We previously showed that macaque caudal intraparietal (CIP) area neurons possess robust 3D visual representations, carry choice- and saccade-related activity, and exhibit experience-dependent sensorimotor associations (Chang et al. (elifesciences.org)
  • In many locations within the brain, adjacent neurons have receptive fields that include slightly different, but overlapping portions of the visual field. (absoluteastronomy.com)
  • we found that excitatory broadband high-frequency activity transients, driven by eye blinks, are suppressed in higher-level but not early visual cortex. (biorxiv.org)
  • Early visual cortex sites responded with positive transients to both conditions. (biorxiv.org)
  • These findings indicate that early visual cortex is highly unstable compared to higher-level visual regions which apparently constitute the main target of stabilizing extra-retinal oculomotor influences. (biorxiv.org)
  • Although the content of working memory (WM) can be decoded from the spatial patterns of brain activity in early visual cortex, how populations encode WM representations remains unclear. (mit.edu)
  • Top-Down Modulation of Human Early Visual Cortex after Stimulus Offset Supports Successful Postcued Report. (uni-trier.de)
  • Predicting the stream of consciousness from activity in early visual cortex. (mpg.de)
  • Attentional integration between anatomically distinct stimulus representations in early visual cortex. (mpg.de)
  • An increased activation was found for spatiotemporally unpredictable stimuli directly after eye-movement, indicating the predictive feedback was projected to the new retinotopic region with saccade. (gla.ac.uk)
  • In a study of nine human subjects, we determined whether such facilitation (the "gap effect") occurs equivalently for the disappearance of fixated auditory stimuli and fixated visual stimuli. (mit.edu)
  • The results demonstrated equivalent facilitatory effects due to the disappearance of fixated auditory and visual stimuli and are consistent with the presumed role of the superior colliculus in the gap effect. (mit.edu)
  • Processing of the stimuli from the visual cortex occurs in three dozen different regions of the brain by modules that detect edges, vertical, horizontal, and on a slant. (luminous-landscape.com)
  • Here, we show that the magnitude of perceptual compression for a wide variety of probe stimuli and saccade amplitudes is quantitatively predicted by a simple heuristic model based on the geometry of retinotopic representations in the primate brain. (jneurosci.org)
  • As new visual stimuli are transmitted to the visual cortex and further information is acquired by moving the line of sight (in microsaccades), this gaze movement was predicted to be impaired in PD, causing visual cognitive impairment. (mdsabstracts.org)
  • 1st, SC supports unisensory processing inside the visual, auditory and somatosensory domains accessible inside a topographicallyordered representation to orient the animal to the supply of sensory stimuli. (hsvinhibitor.com)
  • Hemianopia patients present difficulties in detecting stimuli in the defective visual field and show defective scanning and exploration ( 6 ). (frontiersin.org)
  • Retinotopy describes the spatial organization of the neuronal responses to visual stimuli. (absoluteastronomy.com)
  • Briefly presented stimuli occurring just before or during a saccadic eye movement are mislocalized, leading to a compression of visual space toward the target of the saccade. (pisavisionlab.org)
  • 2023 ) Occipital and parietal cortex participate in a cortical network for transsaccadic discrimination of object shape and orientation. (neurotree.org)
  • Previous studies have demonstrated an increased activity when processing unpredicted visual stimulation in V1. (gla.ac.uk)
  • Such gaze shifts are themselves a source of powerful retinal stimulation, and so the visual system appears to have evolved mechanisms to maintain perceptual stability during movements of the eyes in space. (jneurosci.org)
  • Moreover, because the representation of the antisaccade goal cannot be the result of bottom-up visual stimulation, it must be evoked by top-down signals presumably originating from frontal and/or parietal cortex. (mit.edu)
  • An experimental and computational framework for modeling multi-muscle responses to transcranial magnetic stimulation of the human motor cortex. (duke.edu)
  • Using electrical stimulation to evoke saccades from the dorsomedial frontal cortex (DMFC) and frontal eye fields (FEF) of rhesus monkeys, parametric tests were conducted to compare the excitability properties of these regions. (duke.edu)
  • These aspects are essential given that some developmental studies attribute to SC a function in fetal learning making use of some kind of vibroacoustic stimulation to explain how the fetus is capable to sense and to study by way of the physique skin [44] and that SC is wellknown as a vital pathway for gaze shifting and saccade handle [45,46]. (hsvinhibitor.com)
  • Saccades differentially modulate human LGN and V1 responses in the presence and absence of visual stimulation. (mpg.de)
  • In this case series, we sought to characterize the feasibility and potential effectiveness of a home-based visual rehabilitation program in hemianopia patients using immersive virtual-reality stimulation. (frontiersin.org)
  • Two patients, one with homonymous hemianopia and the other with bitemporal hemianopia, consecutive to pediatric brain tumors, with no prior visual rehabilitation performed 15 min of home-based audiovisual stimulation every 2 days for 6 weeks (case 2) and 7 weeks (case 1) between February and August 2020. (frontiersin.org)
  • This thesis investigates the ability of active perception to redirect predictive signals to new retinotopic locations with saccades. (gla.ac.uk)
  • An introduction into active visual perception is provided in Chapter 1. (gla.ac.uk)
  • However, in the laboratory it becomes possible to induce highly inaccurate spatial percepts that may provide insights into the brain mechanisms that underlie the perception of visual space. (jneurosci.org)
  • [12] It is characterized by massive neuronal loss in the hippocampus and cortex impairing memory and executive functioning [13] , including dysfunction of speech, language, and perception. (aao.org)
  • 2022 ) Linear vector models of time perception account for saccade and stimulus novelty interactions. (neurotree.org)
  • The superior colliculus, which is older in terms of evolution, is typically less studied and considered less vital for visual perception even though it is responsible for saccades, rapid eye movement between two fixed points, as well as facial recognition. (kyoto-u.ac.jp)
  • By applying our model to the large-scale visual system model, it is expected to be able to evaluate the phenomena, for example, age dependent perception on visual illusions, blur compensation in retina or visual cortex, and so on. (biomedcentral.com)
  • Neural basis of visual body perception and self-other distinction. (mpg.de)
  • We show the feasibility in real-world conditions and potential effectiveness of such technology on visual perception and quality of life. (frontiersin.org)
  • Patients with hemianopia naturally develop oculomotor strategies (more saccades toward the blind field) to compensate for visual field loss ( 8 , 9 ), but visual rehabilitation procedure must still be developed to optimize/improve visual perception in the blind field and enhance the quality of life. (frontiersin.org)
  • We particularly focus on how our brain processes three-dimensional visual information and constructs the perception of depth and shape. (kochi-tech.ac.jp)
  • Compensatory saccades made to remembered targets following orbital displacement by electrically stimulating the dorsomedial frontal cortex or frontal eye fields of primates. (duke.edu)
  • Electrically evoked saccades from the dorsomedial frontal cortex and frontal eye fields: a parametric evaluation reveals differences between areas. (duke.edu)
  • Compared with motor imagery, motor execution generated higher activation in all 3 regions of interest studied: the supplementary motor area (SMA), primary motor cortex (M1), and thalamus. (jamanetwork.com)
  • This model indicates that the motor execution task modulates the excitatory outputs from the thalamus to the motor cortex (M1) as well as the thalamus itself. (jamanetwork.com)
  • The insets display the results from the random-effects general linear model analysis together with the group coordinates of the regions included in the model: the supplementary motor area (SMA), primary motor cortex (M1), and thalamus. (jamanetwork.com)
  • C, Mean fractional anisotropy (FA) values for the fibers connecting the thalamus with the motor cortex (M1) and thalamus with the supplementary motor area (SMA) for each patient and the mean of the healthy controls. (jamanetwork.com)
  • The premotor cortex is an area of the motor cortex that lies within the frontal lobe just anterior to the primary motor cortex. (wewantscience.com)
  • The premotor cortex sends axons to the primary motor cortex as well as directly to the spinal cord, so it is likely that this area plays an important role in the control of motor behavior. (wewantscience.com)
  • This is because it is a more complex and specialized area than the primary motor cortex, which is more involved in simple movements that require little planning, such as palpating an object with the hand. (wewantscience.com)
  • Hemispheric Differences in Frontal and Parietal Influences on Human Occipital Cortex: Direct Confirmation with Concurrent TMS-fMRI. (uni-trier.de)
  • 2022 ) Action planning modulates the representation of object features in human fronto-parietal and occipital cortex. (neurotree.org)
  • Here, we used a common experimental design to investigate two areas that bridge the parieto-occipital junction in macaque monkeys: intermediate visual area V3A and the caudal intraparietal (CIP) area. (elifesciences.org)
  • We compared saccades (1.3°-3.7°) initiated during inspection of large individual visual objects with similarly-sized external stimulus displacements. (biorxiv.org)
  • Relative to when a fixated stimulus remains visible, saccadic latencies are facilitated when a fixated stimulus is extinguished simultaneously with or prior to the appearance of an eccentric auditory, visual, or combined visual-auditory target. (mit.edu)
  • In the present study, a fixated auditory (noise) stimulus remained present (overlap) or else was extinguished simultaneously with (step) or 200 msec prior to (gap) the appearance of a visual, auditory (tone), or combined visual-auditory target 10° to the left or right of fixation. (mit.edu)
  • We could reconstruct the saccade goal even when we dissociated the visual stimulus from the saccade goal using a memory-guided antisaccade procedure. (mit.edu)
  • By comparing the spatiotemporal population dynamics, we find that the representations in visual cortex are stable but can also evolve from a representation of a remembered visual stimulus to a prospective goal. (mit.edu)
  • Although erroneous saccades towards a visual stimulus are commonly labelled reflexive in patients with PFC damage or dysfunction, the latencies of most of these saccades are outside of the range of express saccades, which are triggered directly by the visual stimulus. (nih.gov)
  • 2022 ) Saccades and presaccadic stimulus repetition alter cortical network topology and dynamics: evidence from EEG and graph theoretical analysis. (neurotree.org)
  • Anatomically, we show that the cOFC can be subdivided according to its much stronger (medial) or weaker (lateral) bidirectional anatomical connectivity with the posterior cingulate cortex (PCC). (nature.com)
  • We hypothesized that the key to understanding the role of cOFC in the transformations associated with choice is through its connectivity with another region involved in economic choice: the posterior cingulate cortex (PCC). (nature.com)
  • RESULTS: The dynamic atlas demonstrated transient high-gamma suppression in the striatal cortex before saccade onset and high-gamma augmentation subsequently involving the widespread posterior brain regions. (bvsalud.org)
  • Connolly JD , Vuong QC , Thiele A . Gaze-dependent topography in human posterior parietal cortex. (neurotree.org)
  • Optic ataxia as a model to investigate the role of the posterior parietal cortex in visually guided action: evidence from studies of patient M.H. Frontiers in Human Neuroscience . (neurotree.org)
  • Odor quality coding and categorization in human posterior piriform cortex. (mpg.de)
  • Functional heterogeneity in the left lateral posterior parietal cortex during visual and haptic crossmodal dot‐surface matching. (kochi-tech.ac.jp)
  • Firstly, the presence of internal generative models for the visual environment, secondly feedback connections which project prediction signals of the model to lower cortical processing areas to interact with sensory input, and thirdly prediction errors which are produced when the sensory input is not predicted by feedback signals. (gla.ac.uk)
  • A psychophysical study is presented in Chapter 2 which provides evidence for the transference of predictive signals across saccades. (gla.ac.uk)
  • Importantly, the detection advantage for in-time targets was found 50 - 100 ms after saccade indicating transference of predictive signals across saccade. (gla.ac.uk)
  • These signals travel along the optic nerve fibers to the brain, where they are interpreted as vision in the visual cortex. (wikipedia.org)
  • Under this assumption, the psychophysical data on perisaccadic compression can be appreciated intuitively by imagining that, around the time of a saccade, the brain confounds nearby oculomotor and sensory signals while attempting to localize the position of objects in visual space. (jneurosci.org)
  • However, we have derived a novel formulation that captures the interaction between oculomotor and visual signals on a retinotopic map and have tested this hypothesis psychophysically across a wide range of conditions. (jneurosci.org)
  • Therefore, the population dynamics in visual cortex encode WM representations, and these representations can be sculpted by top-down signals from frontal and parietal cortex. (mit.edu)
  • Saccade preparation signals in the human frontal and parietal cortices. (neurotree.org)
  • Gaze-related signals in frontal cortex are often used as an experimental model for visual working memory. (eneuro.org)
  • Sensorimotor associations between 3D orientation and saccade direction preferences were stronger in CIP than V3A, and moderated by choice signals in both areas. (elifesciences.org)
  • Together, the results explicate parallel representations, hierarchical transformations, and functional associations of visual and saccade-related signals at a key juncture in the 'where' pathway. (elifesciences.org)
  • Brain tumor and its treatment can affect the visual system at different levels, from the optic nerves (through compression or infiltration), to subcortical structures like the superior colliculus (SC) and lateral geniculate nuclei (LGN) to optic tracts, optic radiations, and visual cortices ( 1 - 4 ). (frontiersin.org)
  • Indeed, we find that trial-by-trial fluctuations in delay period activity in frontal and parietal cortex correlate with the precision with which our model reconstructed the maintained saccade goal based on the pattern of activity in visual cortex. (mit.edu)
  • Primates and many other vertebrates use three types of voluntary eye movement to track objects of interest: smooth pursuit, vergence shifts and saccades. (wikipedia.org)
  • The Role of the Anterior Cingulate Cortex in Conflict Processing: Evidence from Reverse Stroop Interference. (uni-trier.de)
  • That is, the anterior cingulate cortex identifies potential and significant conflicts--instances in which a cue seems to elicit competing tendencies (for a discussion, see Botvinick, Nystrom, Fissell, Carter, & Cohen, 1999). (sicotests.com)
  • many of these subprocesses are associated with the central orbitofrontal cortex (cOFC). (nature.com)
  • The orbitofrontal cortex also comprises the ventromedial, basal, and orbital areas. (sicotests.com)
  • Evidence for the transfer of spatiotemporally predictive feedback across saccade was supported by the fMRI study presented in Chapter 3. (gla.ac.uk)
  • Attentional Preparation for a Lateralized Visual Distractor: Behavioral and fMRI Evidence. (uni-trier.de)
  • Preparatory gap and memory-delay fMRI activation in the human frontal eye field is higher for pointing as compared to saccade trials Journal of Vision . (neurotree.org)
  • FMRI activation related to preparatory set is correlated with saccade latency in human frontal eye fields but not in the supplementary motor area Journal of Vision . (neurotree.org)
  • Connolly JD , Goodale MA , DeSouza JF , Menon RS , Vilis T . A comparison of frontoparietal fMRI activation during anti-saccades and anti-pointing. (neurotree.org)
  • Frontal influences on human retinotopic visual cortex revealed by combining TMS with fMRI and psychophysics. (mpg.de)
  • Neuron activation in the postmotor cortex is a significant part of monkey motor learning and recovery following a stroke or traumatic brain injury. (wewantscience.com)
  • Due to the nature of vision, we rapidly sample our visual environment using ballistic eye-movements called saccades. (gla.ac.uk)
  • A key hallmark of visual perceptual awareness is robustness to instabilities arising from unnoticeable eye and eyelid movements. (biorxiv.org)
  • Therefore, the saccade-compensating methodology enables researchers and healthcare professionals to rule out eye movements as a source of inaccuracies in pre-, post-, and follow-up assessments. (bmj.com)
  • In some studies, it is known that axons from the premotor cortex are sent to areas of the supplementary motor area (SMA), which are responsible for selecting and programming sequences of movements. (wewantscience.com)
  • Both areas contained saccade-related activity that predicted the direction/timing of eye movements. (elifesciences.org)
  • Saccades are quick, simultaneous movements of both eyes in the same direction. (absoluteastronomy.com)
  • We determined whether high-gamma activity at 70-110 Hz preceding saccade onset would predict upcoming ocular behaviors. (bvsalud.org)
  • Before the onset of PISA, there was a decreased blood flow in the correlative visual cortex and impairment of spatial cognition. (mdsabstracts.org)
  • In most cases this has been measured in subjects over-trained to perform a stereotyped and unnatural task where saccades are repeatedly driven to the same location, marked by a highly salient abrupt onset. (pisavisionlab.org)
  • The mislocalization also remained similar when the expert observers were tested in a condition leading to less stereotypical saccadic behavior-with no abrupt onset marking the saccade target location. (pisavisionlab.org)
  • The internal model of motion was created prior to saccade and tested at a post-saccadic retinotopic region of V1. (gla.ac.uk)
  • While the SC is a structure late to mature, the somatosensory modality could be the 1st modality to become mapped within the third trimester of pregnancy [42], followed by vision with observations of occular saccades behaviors [43]. (hsvinhibitor.com)
  • These results assign to area PEc, classically considered as a somatosensory association cortex, a new visuomotor role. (nih.gov)
  • How Cortical Circuits Implement Cortical Computations: Mouse Visual Cortex as a Model. (ucsf.edu)
  • Specifically, we propose that perisaccadic compression is determined by the distance between the probe and saccade end point on a map that has a logarithmic representation of visual space, similar to those found in numerous cortical and subcortical visual structures. (jneurosci.org)
  • This study compares the neuronal activity of two interconnected cortical areas in the dorsal visual pathway, V3A and CIP, during perceptual decisions based on judging the tilt of 3D visual patterns. (elifesciences.org)
  • Ophthalmologic findings of AD include visual field deficits, decreased contrast sensitivity, impaired oculomotor function, and abnormal viewing behavior. (aao.org)
  • These results indicate that perisaccadic compression is a robust behavior, insensitive to the specific paradigm used to drive saccades and to the level of practice with the saccade task. (pisavisionlab.org)
  • Parallel feedback pathways in visual cortex of cats revealed through a modified rabies virus. (neurotree.org)
  • Visual orienting of attention and gaze are widely considered to be mediated by shared neural pathways, with automatic phenomena such as inhibition of return (IOR)--the bias against returning to recently visited locations--being generated via the direct pathway from retina to superior colliculus (SC). (ox.ac.uk)
  • Brain State-Dependent Modulation of Thalamic Visual Processing by Cortico-Thalamic Feedback. (ucsf.edu)
  • This perisaccadic compression of visual space has been the subject of much research, but few studies have attempted to relate it to specific brain mechanisms. (jneurosci.org)
  • Importantly, because our model can be characterized by a simple closed-form expression, it also makes specific predictions about the outcome of future psychophysical experiments and the characteristics of brain structures that might be involved in perceptual estimates of the metrics of visual space. (jneurosci.org)
  • Visual search results from adaptive psychophysical procedures are reported from 12 healthy individuals and 23 individuals with unilateral brain injury. (cambridge.org)
  • These clusters are found in many brain regions, for example, the visual cortex and the superior colliculus. (kyoto-u.ac.jp)
  • These findings suggest that the brain may optimize visual information processing depending on its conscious state. (kyoto-u.ac.jp)
  • Precise and reliable visual field diagnostics is of crucial importance when diagnosing progression in eye diseases or evaluating rehabilitation after brain lesions. (bmj.com)
  • Visual field loss is frequent in patients with brain tumors, worsening their daily life and exacerbating the burden of disease, and no supportive care strategies exist. (frontiersin.org)
  • This is the first report of a home-based virtual-reality visual rehabilitation program for adult patients with hemianopia consecutive to a pediatric brain tumor. (frontiersin.org)
  • Children with brain tumors can present visual impairments like decreased visual acuity and contrast sensitivity (CS), loss of color vision, and visual field loss such as hemianopias ( 1 - 5 ). (frontiersin.org)
  • Here, we report, for the first time, the feasibility and potential effectiveness of a visual rehabilitation procedure consecutive to a pediatric brain tumor in two young adult patients with hemianopia. (frontiersin.org)
  • The frontal eye fields (FEFs) participate in both working memory and sensorimotor transformations for saccades, but their role in integrating these functions through time remains unclear. (eneuro.org)
  • The most common long-term sequelae of PCA strokes are visual and sensory deficits. (medscape.com)
  • Independent neural activity patterns for sensory-and confidence-based information maintenance during category-selective visual processing. (belopolsky.nl)
  • The aim of the thesis is to provide evidence of the relevance of generative models in a more naturalistic viewing paradigm (i.e. across saccades). (gla.ac.uk)
  • Objective Several studies report evidence for training-related neuroplasticity in the visual cortex, while other studies suggest that improvements simply reflect inadequate eye fixation control during perimetric prediagnostics and postdiagnostics. (bmj.com)
  • 2022 ) Integration of allocentric and egocentric visual information in a convolutional/multilayer perceptron network model of goal-directed gaze shifts. (neurotree.org)
  • Circuits for presaccadic visual remapping. (duke.edu)
  • In contrast, in both dorsal and ventral higher-level sites the response to saccades (but not to external displacements) was suppressed. (biorxiv.org)
  • Distractor displacements during saccades are reflected in the time-course of saccade curvature. (belopolsky.nl)
  • Areas active during a pointing but not a saccade delay are medial to saccade-and-pointing network Journal of Vision . (neurotree.org)
  • Parallel processing strategies of the primate visual system. (rctn.org)
  • We studied the effective spread of lidocaine to inactivate neural tissue in the frontal cortex of the rhesus monkey. (duke.edu)
  • We apply our approach to the problem of decoding eye movement intentions from LFPs collected in macaque cortex while the animals perform memory-guided visual saccades to one of eight target locations. (academic-accelerator.com)
  • Quantitative studies of single-cell properties in monkey striate cortex. (rctn.org)
  • Detection of object displacement during a saccade is prioritized by the oculomotor system. (belopolsky.nl)
  • The role of the oculomotor system in updating visual-spatial working memory across saccades, PloS one,11, e0161829. (belopolsky.nl)
  • Target-distractor competition cannot be resolved across a saccade. (belopolsky.nl)
  • Using this approach, we could successfully reconstruct the locations of memory-guided saccade goals based on the pattern of activity in visual cortex during a memory delay. (mit.edu)
  • We addressed this question by studying perisaccadic localization in a set of participants with no prior experience in eye-movement research, measuring localization performance as they practiced the saccade task. (pisavisionlab.org)
  • Visual input signaling threat gains preferential access to awareness in a breaking continuous flash suppression paradigm. (belopolsky.nl)
  • A genetically defined tecto-thalamic pathway drives a system of superior-colliculus-dependent visual cortices. (ucsf.edu)
  • Measurement of the various retinal layers allows for objective, quantitative assessment of structural damage in the visual pathway. (aao.org)