scholarly journals The role of posterior ventral stream areas for viewpoint-invariant object recognition

2021 ◽  
Author(s):  
Sophia Nestmann ◽  
Hans-Otto Karnath ◽  
Johannes Rennig
Keyword(s):  
Object Recognition ◽  
Object Perception ◽  
Ventral Stream ◽  
Visual Object ◽  
Visual Stream ◽  
Activation Patterns ◽  
Object Constancy ◽  
Invariant Object Recognition ◽  
Fmri Experiment ◽  
The Right

Object constancy is one of the most crucial mechanisms of the human visual system enabling viewpoint invariant object recognition. However, the neuronal foundations of object constancy are widely unknown. Research has shown that the ventral visual stream is involved in processing of various kinds of object stimuli and that several regions along the ventral stream are possibly sensitive to the orientation of an object in space. To systematically address the question of viewpoint sensitive object perception, we conducted a study with stroke patients as well as an fMRI experiment with healthy participants applying object stimuli in several spatial orientations, for example in typical and atypical viewing conditions. In the fMRI experiment, we found stronger BOLD signals and above-chance classification accuracies for objects presented in atypical viewing conditions in fusiform face sensitive and lateral occipito-temporal object preferring areas. In the behavioral patient study, we observed that lesions of the right fusiform gyrus were associated with lower performance in object recognition for atypical views. The complementary results from both experiments emphasize the contributions of fusiform and lateral-occipital areas to visual object constancy and indicate that visual object constancy is particularly enabled through increased neuronal activity and specific activation patterns for objects in demanding viewing conditions.

scholarly journals A performance-optimized model of neural responses across the ventral visual stream

2016 ◽  
Author(s):  
Darren Seibert ◽  
Daniel L Yamins ◽  
Diego Ardila ◽  
Ha Hong ◽  
James J DiCarlo ◽  
...  
Keyword(s):  
Neural Network ◽  
Visual Cortex ◽  
Object Recognition ◽  
Recognition Performance ◽  
Ventral Stream ◽  
Visual Object ◽  
Emergent Properties ◽  
Visual Stream ◽  
Response Properties ◽  
High Level

Human visual object recognition is subserved by a multitude of cortical areas. To make sense of this system, one line of research focused on response properties of primary visual cortex neurons and developed theoretical models of a set of canonical computations such as convolution, thresholding, exponentiating and normalization that could be hierarchically repeated to give rise to more complex representations. Another line or research focused on response properties of high-level visual cortex and linked these to semantic categories useful for object recognition. Here, we hypothesized that the panoply of visual representations in the human ventral stream may be understood as emergent properties of a system constrained both by simple canonical computations and by top-level, object recognition functionality in a single unified framework (Yamins et al., 2014; Khaligh-Razavi and Kriegeskorte, 2014; Guclu and van Gerven, 2015). We built a deep convolutional neural network model optimized for object recognition and compared representations at various model levels using representational similarity analysis to human functional imaging responses elicited from viewing hundreds of image stimuli. Neural network layers developed representations that corresponded in a hierarchical consistent fashion to visual areas from V1 to LOC. This correspondence increased with optimization of the model's recognition performance. These findings support a unified view of the ventral stream in which representations from the earliest to the latest stages can be understood as being built from basic computations inspired by modeling of early visual cortex shaped by optimization for high-level object-based performance constraints.

Preserved Expert Object Recognition in a Case of Visual Hemiagnosia

2018 ◽  
Vol 30 (2) ◽  
pp. 131-143 ◽  
Author(s):  
Johannes Rennig ◽  
Sonja Cornelsen ◽  
Helmut Wilhelm ◽  
Marc Himmelbach ◽  
Hans-Otto Karnath
Keyword(s):  
Object Recognition ◽  
Expert Knowledge ◽  
Early Stage ◽  
Visual Object ◽  
Top Down ◽  
Visual Stream ◽  
Object Processing ◽  
Visual Expertise ◽  
Everyday Objects ◽  
The Right

We examined a stroke patient (HWS) with a unilateral lesion of the right medial ventral visual stream, involving the right fusiform and parahippocampal gyri. In a number of object recognition tests with lateralized presentations of target stimuli, HWS showed significant symptoms of hemiagnosia with contralesional recognition deficits for everyday objects. We further explored the patient's capacities of visual expertise that were acquired before the current perceptual impairment became effective. We confronted him with objects he was an expert for already before stroke onset and compared this performance with the recognition of familiar everyday objects. HWS was able to identify significantly more of the specific (“expert”) than of the everyday objects on the affected contralesional side. This observation of better expert object recognition in visual hemiagnosia allows for several interpretations. The results may be caused by enhanced information processing for expert objects in the ventral system in the affected or the intact hemisphere. Expert knowledge could trigger top–down mechanisms supporting object recognition despite of impaired basic functions of object processing. More importantly, the current work demonstrates that top–down mechanisms of visual expertise influence object recognition at an early stage, probably before visual object information propagates to modules of higher object recognition. Because HWS showed a lesion to the fusiform gyrus and spared capacities of expert object recognition, the current study emphasizes possible contributions of areas outside the ventral stream to visual expertise.

scholarly journals Marmoset invariant object recognition behavior mirrors that of humans and macaques at fine scale

2020 ◽  
Author(s):  
Alexander J.E. Kell ◽  
Sophie L. Bokor ◽  
You-Nah Jeon ◽  
Tahereh Toosi ◽  
Elias B. Issa
Keyword(s):  
Object Recognition ◽  
Model Organism ◽  
High Standard ◽  
Visual Object ◽  
Visual Object Recognition ◽  
Visual Neuroscience ◽  
Brain Functions ◽  
Invariant Object Recognition ◽  
Small Model ◽  
High Level

The marmoset—a small monkey with a flat cortex—offers powerful techniques for studying neural circuits in a primate. However, it remains unclear whether brain functions typically studied in larger primates can be studied in the marmoset. Here, we asked whether the 300-gram marmosets’ perceptual and cognitive repertoire approaches human levels or is instead closer to rodents’. Using high-level visual object recognition as a testbed, we found that on the same task marmosets substantially outperformed rats and generalized far more robustly across images, all while performing ∼1000 trials/day. We then compared marmosets against the high standard of human behavior. Across the same 400 images, marmosets’ image-by-image recognition behavior was strikingly human-like—essentially as human-like as macaques’. These results demonstrate that marmosets have been substantially underestimated and that high-level abilities have been conserved across simian primates. Consequently, marmosets are a potent small model organism for visual neuroscience, and perhaps beyond.

scholarly journals Fast recurrent processing via ventral prefrontal cortex is needed by the primate ventral stream for robust core visual object recognition

2020 ◽  
Author(s):  
Kohitij Kar ◽  
James J DiCarlo
Keyword(s):  
Prefrontal Cortex ◽  
Object Recognition ◽  
Late Phase ◽  
Ventral Stream ◽  
Neural Population ◽  
Visual Object ◽  
Visual Object Recognition ◽  
Neural Network Models ◽  
Recurrent Processing ◽  
Ventral Prefrontal Cortex

SummaryDistributed neural population spiking patterns in macaque inferior temporal (IT) cortex that support core visual object recognition require additional time to develop for specific (“late-solved”) images suggesting the necessity of recurrent processing in these computations. Which brain circuit motifs are most responsible for computing and transmitting these putative recurrent signals to IT? To test whether the ventral prefrontal cortex (vPFC) is a critical recurrent circuit node in this system, here we pharmacologically inactivated parts of the vPFC and simultaneously measured IT population activity, while monkeys performed object discrimination tasks. Our results show that vPFC inactivation deteriorated the quality of the late-phase (>150 ms from image onset) IT population code, along with commensurate, specific behavioral deficits for “late-solved” images. Finally, silencing vPFC caused the monkeys’ IT activity patterns and behavior to become more like those produced by feedforward artificial neural network models of the ventral stream. Together with prior work, these results argue that fast recurrent processing through the vPFC is critical to the production of behaviorally-sufficient object representations in IT.

Age-Related Changes in the Allocation of Vertical Attention

2018 ◽  
Vol 24 (10) ◽  
pp. 1121-1124 ◽  
Author(s):  
Aleksandra Mańkowska ◽  
Kenneth M. Heilman ◽  
John B. Williamson ◽  
Michał Harciarek
Keyword(s):  
Spatial Attention ◽  
Right Hemisphere ◽  
Ventral Stream ◽  
Midsagittal Plane ◽  
Visual Stream ◽  
Leftward Bias ◽  
Healthy Elderly ◽  
Age Related ◽  
The Right ◽  
Dorsal Visual Stream

AbstractObjectives: Healthy individuals often have a leftward and upward attentional spatial bias; however, there is a reduction of this leftward bias with aging. The right hemisphere mediates leftward spatial attention and age-related reduction of right hemispheric activity may account for this reduced leftward bias. The right hemisphere also appears to be responsible for upward bias, and this upward bias might reduce with aging. Alternatively, whereas the dorsal visual stream allocates attention downward, the ventral stream allocates attention upward. Since with aging there is a greater atrophy of the dorsal than ventral stream, older participants may reveal a greater upward bias. The main purpose of this study was to learn if aging influences the vertical allocation of spatial attention. Methods: Twenty-six young (17 males; mean age 44.62±2.57 years) and 25 healthy elderly (13 males; mean age 72.04±.98 years), right-handed adults performed line bisections using 24 vertical lines (24 cm long and 2 mm thick) aligned with their midsagittal plane. Results: Older adults had a significantly greater upward bias than did younger adults. Conclusions: Normal upward attentional bias increases with aging, possibly due to an age-related reduction of the dorsal attentional stream that is responsible for the allocation of downward attention. (JINS, 2018, 24, 1121–1124)

scholarly journals Clinical and Cognitive Phenotype of Mild Cognitive Impairment Evolving to Dementia with Lewy Bodies

2015 ◽  
Vol 5 (3) ◽  
pp. 442-449 ◽  
Author(s):  
Annachiara Cagnin ◽  
Cinzia Bussè ◽  
Simona Gardini ◽  
Nela Jelcic ◽  
Caterina Guzzo ◽  
...  
Keyword(s):  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Visual Attention ◽  
Dementia With Lewy Bodies ◽  
Rating Scale ◽  
Lewy Bodies ◽  
Object Perception ◽  
Visual Object ◽  
Visual Stream ◽  
Extrapyramidal Signs

Objective: The aim of this study was to determine which characteristics could better distinguish dementia with Lewy bodies (DLB) from Alzheimer's disease (AD) at the mild cognitive impairment (MCI) stage, with particular emphasis on visual space and object perception abilities. Methods: Fifty-three patients with mild cognitive deficits that were eventually diagnosed with probable DLB (MCI-DLB: n = 25) and AD (MCI-AD: n = 28) at a 3-year follow-up were retrospectively studied. At the first visit, the patients underwent cognitive assessment including the Qualitative Scoring Mini Mental State Examination Pentagon Test and the Visual Object and Space Perception Battery. The Neuropsychiatric Inventory Questionnaire, Unified Parkinson's Disease Rating Scale (UPDRS) and questionnaires for cognitive fluctuations and sleep disorders were also administered. Results: The best clinical predictor of DLB was the presence of soft extrapyramidal signs (mean UPDRS score: 4.04 ± 5.9) detected in 72% of patients, followed by REM sleep behavior disorder (60%) and fluctuations (60%). Wrong performances in the pentagon's number of angles were obtained in 44% of DLB and 3.7% of AD patients and correlated with speed of visual attention. Executive functions, visual attention and visuospatial abilities were worse in DLB, while verbal episodic memory impairment was greater in AD. Deficits in the visual-perceptual domain were present in both MCI-DLB and AD. Conclusions: Poor performance in the pentagon's number of angles is specific of DLB and correlates with speed of visual attention. The dorsal visual stream seems specifically more impaired in MCI-DLB with respect to the ventral visual stream, the latter being involved in both DLB and AD. These cognitive features, associated with subtle extrapyramidal signs, should alert clinicians to a diagnostic hypothesis of DLB.

scholarly journals Impaired Visual Object Recognition and Dorsal/Ventral Stream Interaction in Schizophrenia

2002 ◽  
Vol 59 (11) ◽  
pp. 1011 ◽  
Author(s):  
Glen M. Doniger ◽  
John J. Foxe ◽  
Micah M. Murray ◽  
Beth A. Higgins ◽  
Daniel C. Javitt
Keyword(s):  
Object Recognition ◽  
Ventral Stream ◽  
Visual Object ◽  
Visual Object Recognition

From Knowing What to Knowing Where: Modeling Object-Based Attention with Feedback Disinhibition of Activation

2001 ◽  
Vol 13 (4) ◽  
pp. 479-491 ◽  
Author(s):  
Frank van der Velde ◽  
Marc de Kamps
Keyword(s):  
Dorsal Stream ◽  
Gain Control ◽  
Neural Model ◽  
Ventral Stream ◽  
Visual Object ◽  
Selective Activation ◽  
Visual Stream ◽  
Search Tasks ◽  
Object Based ◽  
Feedback Activation

We propose a neural model of visual object-based attention in which the identity of an object is used to select its location in an array of objects. The model is based on neural activity observed in visual search tasks performed by monkeys. In the model, the identity of the object (target) is selected in the higher areas of the ventral stream by means of a cue. Feedback activation from these higher areas carries information about the identity of the target to the (lower) retinotopic areas of the ventral stream. In these areas, the feedback activation interacts with feedforward activation produced by the object array. The interaction occurs in local microcircuits, and results in a selective activation on locations in the retinotopic areas of the visual stream that correspond to the location of the target in the object array. The selective activation consists of a form of gain control, produced by disinhibition. Transmitted to the dorsal stream, this activation directs spatial attention to the location of the target. In this way, an action directed at the target can be generated.

Two Categorical Stages of Object Recognition

Perception ◽  
1978 ◽  
Vol 7 (6) ◽  
pp. 695-705 ◽  
Author(s):  
Elizabeth K Warrington ◽  
Angela M Taylor
Keyword(s):  
Object Recognition ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
Visual Object ◽  
Visual Object Recognition ◽  
Perceptual Categorization ◽  
Categorization Task ◽  
Semantic Categorization ◽  
Tentative Model ◽  
The Right

Visual object recognition was investigated in a group of eighty-one patients with right- or left-hemisphere lesions. Two tasks were used, one maximizing perceptual categorization by physical identity, the other maximizing semantic categorization by functional identity. The right-hemisphere group showed impairment on the perceptual categorization task and the left-hemisphere group were impaired on the semantic categorization task. The findings are discussed in terms of categorical stages of object recognition. A tentative model of their cerebral organization is suggested.

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