An action-specific effect on perception that avoids all pitfalls

2016 ◽  
Vol 39 ◽  
Author(s):  
Jessica K. Witt ◽  
Mila Sugovic ◽  
Nathan L. Tenhundfeld ◽  
Zachary R. King

AbstractThe visual system is influenced by action. Objects that are easier to reach or catch look closer and slower, respectively. Here, we describe evidence for one action-specific effect, and show that none of the six pitfalls can account for the results. Vision is not an isolate module, as shown by this top-down effect of action on perception.

2014 ◽  
Vol 26 (12) ◽  
pp. 2789-2797 ◽  
Author(s):  
Paige E. Scalf ◽  
JeeWon Ahn ◽  
Diane M. Beck ◽  
Alejandro Lleras

The ventral attentional network (VAN) is thought to drive “stimulus driven attention” [e.g., Asplund, C. L., Todd, J. J., Snyder, A. P., & Marois, R. A central role for the lateral prefrontal cortex in goal-directed and stimulus-driven attention. Nature Neuroscience, 13, 507–512, 2010; Shulman, G. L., McAvoy, M. P., Cowan, M. C., Astafiev, S. V., Tansy, A. P., D' Avossa, G., et al. Quantitative analysis of attention and detection signals during visual search. Journal of Neurophysiology, 90, 3384–3397, 2003]; in other words, it instantiates within the current stimulus environment the top–down attentional biases maintained by the dorsal attention network [e.g., Kincade, J. M., Abrams, R. A., Astafiev, S. V., Shulman, G. L., & Corbetta, M. An event-related functional magnetic resonance imaging study of voluntary and stimulus-driven orienting of attention. The Journal of Neuroscience: The Official Journal of the Society for Neuroscience, 25, 4593–4604, 2005]. Previous work has shown that the dorsal attentional network is sensitive to trial history, such that it is challenged by changes in task goals and facilitated by repetition thereof [e.g., Kristjánsson, A., Vuilleumier, P., Schwartz, S., Macaluso, E., & Driver, J. Neural basis for priming of pop-out during visual search revealed with fMRI. Cerebral Cortex, 17, 1612–1624, 2007]. Here, we investigate whether the VAN also preserves information across trials such that it is challenged when previously rejected stimuli become task relevant. We used fMRI to investigate the sensitivity of the ventral attentional system to prior history effects as measured by the distractor preview effect. This behavioral phenomenon reflects a bias against stimuli that have historically not supported task performance. We found regions traditionally considered to be part of the VAN (right middle frontal gyrus, inferior frontal gyrus and right supramarginal gyrus) [Shulman, G. L., McAvoy, M. P., Cowan, M. C., Astafiev, S. V., Tansy, A. P., D' Avossa, G., et al. Quantitative analysis of attention and detection signals during visual search. Journal of Neurophysiology, 90, 3384–3397, 2003] to be more active when task-relevant stimuli had not supported task performance in a previous trial than when they had. Investigations of the ventral visual system suggest that this effect is more reliably driven by trial history preserved within the VAN than that preserved within the visual system per se. We conclude that VAN maintains its interactions with top–down stimulus biases and bottom–up stimulation across time, allowing previous experience with the stimulus environment to influence attentional biases under current circumstances.


Algorithms ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 167 ◽  
Author(s):  
Dan Malowany ◽  
Hugo Guterman

Computer vision is currently one of the most exciting and rapidly evolving fields of science, which affects numerous industries. Research and development breakthroughs, mainly in the field of convolutional neural networks (CNNs), opened the way to unprecedented sensitivity and precision in object detection and recognition tasks. Nevertheless, the findings in recent years on the sensitivity of neural networks to additive noise, light conditions, and to the wholeness of the training dataset, indicate that this technology still lacks the robustness needed for the autonomous robotic industry. In an attempt to bring computer vision algorithms closer to the capabilities of a human operator, the mechanisms of the human visual system was analyzed in this work. Recent studies show that the mechanisms behind the recognition process in the human brain include continuous generation of predictions based on prior knowledge of the world. These predictions enable rapid generation of contextual hypotheses that bias the outcome of the recognition process. This mechanism is especially advantageous in situations of uncertainty, when visual input is ambiguous. In addition, the human visual system continuously updates its knowledge about the world based on the gaps between its prediction and the visual feedback. CNNs are feed forward in nature and lack such top-down contextual attenuation mechanisms. As a result, although they process massive amounts of visual information during their operation, the information is not transformed into knowledge that can be used to generate contextual predictions and improve their performance. In this work, an architecture was designed that aims to integrate the concepts behind the top-down prediction and learning processes of the human visual system with the state-of-the-art bottom-up object recognition models, e.g., deep CNNs. The work focuses on two mechanisms of the human visual system: anticipation-driven perception and reinforcement-driven learning. Imitating these top-down mechanisms, together with the state-of-the-art bottom-up feed-forward algorithms, resulted in an accurate, robust, and continuously improving target recognition model.


2017 ◽  
Vol 118 (1) ◽  
pp. 564-573 ◽  
Author(s):  
Sonia Poltoratski ◽  
Sam Ling ◽  
Devin McCormack ◽  
Frank Tong

The visual system employs a sophisticated balance of attentional mechanisms: salient stimuli are prioritized for visual processing, yet observers can also ignore such stimuli when their goals require directing attention elsewhere. A powerful determinant of visual salience is local feature contrast: if a local region differs from its immediate surround along one or more feature dimensions, it will appear more salient. We used high-resolution functional MRI (fMRI) at 7T to characterize the modulatory effects of bottom-up salience and top-down voluntary attention within multiple sites along the early visual pathway, including visual areas V1–V4 and the lateral geniculate nucleus (LGN). Observers viewed arrays of spatially distributed gratings, where one of the gratings immediately to the left or right of fixation differed from all other items in orientation or motion direction, making it salient. To investigate the effects of directed attention, observers were cued to attend to the grating to the left or right of fixation, which was either salient or nonsalient. Results revealed reliable additive effects of top-down attention and stimulus-driven salience throughout visual areas V1–hV4. In comparison, the LGN exhibited significant attentional enhancement but was not reliably modulated by orientation- or motion-defined salience. Our findings indicate that top-down effects of spatial attention can influence visual processing at the earliest possible site along the visual pathway, including the LGN, whereas the processing of orientation- and motion-driven salience primarily involves feature-selective interactions that take place in early cortical visual areas. NEW & NOTEWORTHY While spatial attention allows for specific, goal-driven enhancement of stimuli, salient items outside of the current focus of attention must also be prioritized. We used 7T fMRI to compare salience and spatial attentional enhancement along the early visual hierarchy. We report additive effects of attention and bottom-up salience in early visual areas, suggesting that salience enhancement is not contingent on the observer’s attentional state.


2016 ◽  
Vol 39 ◽  
Author(s):  
Ryan Ogilvie ◽  
Peter Carruthers
Keyword(s):  

AbstractFirestone & Scholl (F&S) seem to believe that the viability of a distinction between perception and cognition depends on perception being encapsulated from top-down information. We criticize this assumption and argue that top-down effects can leave the distinction between perception and cognition fully intact. Individuating the visual system is one thing; the question of encapsulation is quite another.


2010 ◽  
Vol 77 (2) ◽  
pp. 126-134 ◽  
Author(s):  
Motohiro Kimura ◽  
Andreas Widmann ◽  
Erich Schröger

2008 ◽  
Vol 276 (1658) ◽  
pp. 861-869 ◽  
Author(s):  
Peter Neri

The human visual system is remarkably sensitive to stimuli conveying actions, for example the fighting action between two agents. A central unresolved question is whether each agent is processed as a whole in one stage, or as subparts (e.g. limbs) that are assembled into an agent at a later stage. We measured the perceptual impact of perturbing an agent either by scrambling individual limbs while leaving the relationship between limbs unaffected or conversely by scrambling the relationship between limbs while leaving individual limbs unaffected. Our measurements differed for the two conditions, providing conclusive evidence against a one-stage model. The results were instead consistent with a two-stage processing pathway: an early bottom-up stage where local motion signals are integrated to reconstruct individual limbs (arms and legs), and a subsequent top-down stage where limbs are combined to represent whole agents.


2020 ◽  
Vol 32 (11) ◽  
pp. 2159-2177
Author(s):  
Dion T. Henare ◽  
Hanna Kadel ◽  
Anna Schubö

The human visual system can only process a fraction of the information present in a typical visual scene, and selection is historically framed as the outcome of bottom–up and top–down control processes. In this study, we evaluated how a third factor, an individual's selection history, interacts with top–down control mechanisms during visual search. Participants in our task were assigned to one of two groups in which they developed a history of either shape or color selection in one task, while searching for a shape singleton in a second task. A voluntary task selection procedure allowed participants to choose which task they would perform on each trial, thereby maximizing their top–down preparation. We recorded EEG throughout and extracted lateralized ERP components that index target selection (NT) and distractor suppression (PD). Our results showed that selection history continued to guide attention during visual search, even when top–down control mechanisms were maximized with voluntary task selection. For participants with a history of color selection, the NT component elicited by a shape target was attenuated when accompanied by a color distractor, and the distractor itself elicited a larger PD component. In addition, task-switching results revealed that participants in the color group had larger, asymmetric switch costs implying increased competition between task sets. Our results support the notion that selection history is a significant factor in attention guidance, orienting the visual system reflexively to objects that contradict an individual's current goals—even when these goals are intrinsically selected and prepared ahead of time.


2010 ◽  
Vol 9 (8) ◽  
pp. 783-783
Author(s):  
S. Gorlin ◽  
M. Meng ◽  
J. Sharma ◽  
H. Sugihara ◽  
M. Sur ◽  
...  

2020 ◽  
Author(s):  
Justin Riddle ◽  
Sangtae Ahn ◽  
Trevor McPherson ◽  
Susan Girdler ◽  
Flavio Frohlich

AbstractThe neuroactive metabolites of the steroid hormones progesterone (P4) and testosterone (T) are GABAergic modulators that influence cognitive control, yet the specific effect of P4 and T on brain network activity remains poorly understood. Here, we investigated if a fundamental oscillatory network activity pattern related to cognitive control, frontal midline theta (FMT) oscillations, are modulated by steroids hormones, P4 and T. We measured the concentration P4 and T using salivary enzyme immunoassay and FMT oscillations using high-density electroencephalography (EEG) during the eyes-open resting state in fifty-five healthy female and male participants. Electrical brain activity was analyzed using Morlet wavelet convolution, beamformer source localization, background noise spectral fitting, and phase amplitude coupling analysis. Steroid hormone concentrations and biological sex were used as predictors for scalp and source-estimated theta oscillations and for top-down theta-gamma phase amplitude coupling. Elevated concentrations of P4 predicted increased FMT oscillatory amplitude across both sexes, and no relationship was found with T. The positive correlation with P4 was specific to the frontal-midline electrodes and survived correction for the background noise of the brain. Using source localization, FMT oscillations were localized to the frontal-parietal network. Additionally, theta amplitude within the frontal-parietal network, but not the default mode network, positively correlated with P4 concentration. Finally, P4 concentration correlated with increased coupling between FMT phase and posterior gamma amplitude. Our results suggest that P4 concentration modulates brain activity via upregulation of theta oscillations in the frontal-parietal network and increased top-down control over posterior cortical sites.Significance StatementThe neuroactive metabolites of the steroid hormones progesterone (P4) and testosterone (T) are GABAergic modulators that influence cognitive control, yet the specific effect of P4 and T on brain network activity remains poorly understood. Here, we investigated if a fundamental oscillatory network activity pattern related to cognitive control, frontal midline theta (FMT) oscillations, are modulated by steroids hormones, P4 and T. Our results suggest that P4 concentration modulates brain activity via upregulation of theta oscillations in the frontal-parietal network and increased top-down control over posterior cortical sites.


2019 ◽  
Author(s):  
Melisa Menceloglu ◽  
Marcia Grabowecky ◽  
Satoru Suzuki

AbstractSpatially heterogeneous flicker, characterized by probabilistic and locally independent luminance modulations, abounds in nature. It is generated by flames, water surfaces, rustling leaves, and so on, and it is pleasant to the senses. It affords spatiotemporal multistability that allows sensory activation conforming to the biases of the visual system, thereby generating the perception of spontaneous motion and likely facilitating the calibration of motion detectors. One may thus hypothesize that spatially heterogeneous flicker might potentially provide restoring stimuli to the visual system that engage fluent (requiring minimal top-down control) and self-calibrating processes. Here, we present some converging behavioral and electrophysiological evidence consistent with this idea. Spatially heterogeneous (multistable) flicker (relative to controls matched in temporal statistics) reduced posterior EEG (electroencephalography) beta power implicated in long-range neural interactions that impose top-down influences on sensory processing. Further, the degree of spatiotemporal multistability, the amount of posterior beta-power reduction, and the aesthetic responses to flicker were closely associated. These results are consistent with the idea that the pleasantness of natural flicker may derive from its spatiotemporal multistability that affords fluent and self-calibrating visual processing.


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