Subordinate Categorization Enhances the Neural Selectivity in Human Object-selective Cortex for Fine Shape Differences

There is substantial evidence that object representations in adults are dynamically updated by learning. However, it is not clear to what extent these effects are induced by active processing of visual objects in a particular task context on top of the effects of mere exposure to the same objects. Here we show that the task does matter. We performed an event-related fMRI adaptation study in which we derived neural selectivity from a release of adaptation. We had two training conditions: “categorized objects” were categorized at a subordinate level based on fine shape differences (Which type of fish is this?), whereas “control objects” were seen equally often in a task context requiring no subordinate categorization (Is this a vase or not?). After training, the object-selective cortex was more selective for differences among categorized objects than for differences among control objects. This result indicates that the task context during training modulates the extent to which object selectivity is enhanced as a result of training.

Download Full-text

Action Prediction During Human-Object Interaction Based on DTW and Early Fusion of Human and Object Representations

10.1007/978-3-030-87156-7_14 ◽

2021 ◽

pp. 169-179

Author(s):

Victoria Manousaki ◽

Konstantinos Papoutsakis ◽

Antonis Argyros

Keyword(s):

Object Representations ◽

Action Prediction ◽

Object Interaction ◽

Early Fusion ◽

Human Object

Download Full-text

The influence of image masking on object representations during rapid serial visual presentation

10.1101/515619 ◽

2019 ◽

Cited By ~ 1

Author(s):

Amanda K. Robinson ◽

Tijl Grootswagers ◽

Thomas A. Carlson

Keyword(s):

Stimulus Duration ◽

Stimulus Presentation ◽

Visual Presentation ◽

Abrupt Onset ◽

Stimulus Onset ◽

Neural Representation ◽

Object Representations ◽

Backward Masking ◽

Time Resolved ◽

Visual Objects

AbstractRapid image presentations combined with time-resolved multivariate analysis methods of EEG or MEG (rapid-MVPA) offer unique potential in assessing the temporal limitations of the human visual system. Recent work has shown that multiple visual objects presented sequentially can be simultaneously decoded from M/EEG recordings. Interestingly, object representations reached higher stages of processing for slower image presentation rates compared to fast rates. This fast rate attenuation is probably caused by forward and backward masking from the other images in the stream. Two factors that are likely to influence masking during rapid streams are stimulus duration and stimulus onset asynchrony (SOA). Here, we disentangle these effects by studying the emerging neural representation of visual objects using rapid-MVPA while independently manipulating stimulus duration and SOA. Our results show that longer SOAs enhance the decodability of neural representations, regardless of stimulus presentation duration, suggesting that subsequent images act as effective backward masks. In contrast, image duration does not appear to have a graded influence on object representations. Interestingly, however, decodability was improved when there was a gap between subsequent images, indicating that an abrupt onset or offset of an image enhances its representation. Our study yields insight into the dynamics of object processing in rapid streams, paving the way for future work using this promising approach.

Download Full-text

Common Structure of Vision and Olfaction

Philosophia ◽

10.1007/s11406-020-00318-y ◽

2021 ◽

Author(s):

Błażej Skrzypulec

Keyword(s):

Object Representations ◽

Visual Objects ◽

Common Structure ◽

The World ◽

Common Opinion

AbstractAccording to a common opinion, human olfactory experiences are significantly different from human visual experiences. For instance, olfaction seems to have only rudimentary abilities to represent space; it is not clear whether olfactory experiences have any mereological structure; and while vision presents the world in terms of objects, it is a matter of debate whether there are olfactory object-representations. This paper argues that despite these differences visual and olfactory experiences share a hierarchical subject/property structure. Within this structure, olfactorily experienced odours and visual objects have the same status: they are primary subjects which unify other represented elements into perceptual units.

Download Full-text

Object representations in the dorsal pathway: fMRI adaptation effects in topographically organized areas of the human posterior parietal cortex

Journal of Vision ◽

10.1167/7.9.332 ◽

2010 ◽

Vol 7 (9) ◽

pp. 332-332

Author(s):

C. Konen ◽

S. Kastner

Keyword(s):

Parietal Cortex ◽

Posterior Parietal Cortex ◽

Object Representations ◽

Dorsal Pathway ◽

Posterior Parietal ◽

Fmri Adaptation ◽

Adaptation Effects

Download Full-text

How learning might strengthen existing visual object representations in human object-selective cortex

NeuroImage ◽

10.1016/j.neuroimage.2015.11.063 ◽

2016 ◽

Vol 127 ◽

pp. 74-85 ◽

Cited By ~ 9

Author(s):

Marijke Brants ◽

Jessica Bulthé ◽

Nicky Daniels ◽

Johan Wagemans ◽

Hans P. Op de Beeck

Keyword(s):

Visual Object ◽

Object Representations ◽

Human Object

Download Full-text

Scenes Modulate Object Processing Before Interacting With Memory Templates

Psychological Science ◽

10.1177/0956797619869905 ◽

2019 ◽

Vol 30 (10) ◽

pp. 1497-1509 ◽

Cited By ~ 1

Author(s):

Surya Gayet ◽

Marius V. Peelen

Keyword(s):

Real World ◽

Template Matching ◽

Ponzo Illusion ◽

Visual Input ◽

The Other ◽

Object Representations ◽

Working Mechanism ◽

Object Processing ◽

Visual Objects ◽

With Memory

When searching for relevant objects in our environment (say, an apple), we create a memory template (a red sphere), which causes our visual system to favor template-matching visual input (applelike objects) at the expense of template-mismatching visual input (e.g., leaves). Although this principle seems straightforward in a lab setting, it poses a problem in naturalistic viewing: Two objects that have the same size on the retina will differ in real-world size if one is nearby and the other is far away. Using the Ponzo illusion to manipulate perceived size while keeping retinal size constant, we demonstrated across 71 participants that visual objects attract attention when their perceived size matches a memory template, compared with mismatching objects that have the same size on the retina. This shows that memory templates affect visual selection after object representations are modulated by scene context, thus providing a working mechanism for template-based search in naturalistic vision.

Download Full-text

NMDA synapses can bias competition between object representations and mediate attentional selection

Behavioral and Brain Sciences ◽

10.1017/s0140525x03400022 ◽

2003 ◽

Vol 26 (1) ◽

pp. 100-101 ◽

Cited By ~ 2

Author(s):

Antonino Raffone ◽

Jaap M. J. Murre ◽

Gezinus Wolters

Keyword(s):

Working Memory ◽

Visual Working Memory ◽

Crucial Role ◽

Gain Control ◽

Attentional Selection ◽

Object Representations ◽

Nmda Antagonists ◽

Cognitive Effects ◽

Visual Objects ◽

Storage Rate

AbstractPhillips & Silverstein emphasize the gain-control properties of NMDA synapses in cognitive coordination. We endorse their view and suggest that NMDA synapses play a crucial role in biased attentional competition and (visual) working memory. Our simulations show that NMDA synapses can control the storage rate of visual objects. We discuss specific predictions of our model about cognitive effects of NMDA-antagonists and schizophrenia.

Download Full-text

Reduced neural selectivity increases fMRI adaptation with age during face discrimination

NeuroImage ◽

10.1016/j.neuroimage.2010.01.107 ◽

2010 ◽

Vol 51 (1) ◽

pp. 336-344 ◽

Cited By ~ 77

Author(s):

Joshua O. Goh ◽

Atsunobu Suzuki ◽

Denise C. Park

Keyword(s):

Fmri Adaptation ◽

Neural Selectivity

Download Full-text

Privileged Coding of Convex Shapes in Human Object-Selective Cortex

Journal of Neurophysiology ◽

10.1152/jn.90310.2008 ◽

2008 ◽

Vol 100 (2) ◽

pp. 753-762 ◽

Cited By ~ 15

Author(s):

Johannes Haushofer ◽

Chris I. Baker ◽

Margaret S. Livingstone ◽

Nancy Kanwisher

Keyword(s):

Binocular Disparity ◽

Lower Sensitivity ◽

Object Representations ◽

Functional Magnetic Resonance ◽

Convex Shape ◽

Posterior Portion ◽

Lateral Occipital Complex ◽

Human Object ◽

Fmri Response ◽

High Level

What is the neural code for object shape? Despite intensive research, the precise nature of object representations in high-level visual cortex remains elusive. Here we use functional magnetic resonance imaging (fMRI) to show that convex shapes are encoded in a privileged fashion by human lateral occipital complex (LOC), a region that has been implicated in object recognition. On each trial, two convex or two concave shapes that were either identical or different were presented sequentially. Critically, the convex and concave stimuli were the same except for a binocular disparity change that reversed the figure–ground assignment. The fMRI response in LOC for convex stimuli was higher for different than that for identical shape pairs, indicating sensitivity to differences in convex shape. However, when the same stimuli were seen as concave, the response for different and identical pairs was the same, indicating lower sensitivity to changes in concave shape than convex shape. This pattern was more pronounced in the anterior than that in the posterior portion of LOC. These results suggest that convex contours could be important elements in cortical object representations.

Download Full-text