scholarly journals Relating visual production and recognition of objects in human visual cortex

2019 ◽  
Author(s):  
Judith E. Fan ◽  
Jeffrey D. Wammes ◽  
Jordan B. Gunn ◽  
Daniel L. K. Yamins ◽  
Kenneth A. Norman ◽  
...  

AbstractDrawing is a powerful tool that can be used to convey rich perceptual information about objects in the world. What are the neural mechanisms that enable us to produce a recognizable drawing of an object, and how does this visual production experience influence how this object is represented in the brain? Here we evaluate the hypothesis that producing and recognizing an object recruit a shared neural representation, such that repeatedly drawing the object can enhance its perceptual discriminability in the brain. We scanned participants using fMRI across three phases of a training study: during training, participants repeatedly drew two objects in an alternating sequence on an MR-compatible tablet; before and after training, they viewed these and two other control objects, allowing us to measure the neural representation of each object in visual cortex. We found that: (1) stimulus-evoked representations of objects in visual cortex are recruited during visually cued production of drawings of these objects, even throughout the period when the object cue is no longer present; (2) the object currently being drawn is prioritized in visual cortex during drawing production, while other repeatedly drawn objects are suppressed; and (3) patterns of connectivity between regions in occipital and parietal cortex supported enhanced decoding of the currently drawn object across the training phase, suggesting a potential substrate for learning how to transform perceptual representations into representational actions. Taken together, our study provides novel insight into the functional relationship between visual production and recognition in the brain.Significance StatementHumans can produce simple line drawings that capture rich information about their perceptual experiences. However, the mechanisms that support this behavior are not well understood. Here we investigate how regions in visual cortex participate in the recognition of an object and the production of a drawing of it. We find that these regions carry diagnostic information about an object in a similar format both during recognition and production, and that practice drawing an object enhances transmission of information about it to downstream regions. Taken together, our study provides novel insight into the functional relationship between visual production and recognition in the brain.

Author(s):  
Hamid Karimi-Rouzbahani ◽  
Alexandra Woolgar ◽  
Anina N. Rich

AbstractThere are many monitoring environments, such as railway control, in which lapses of attention can have tragic consequences. Problematically, sustained monitoring for rare targets is difficult, with more misses and longer reaction times over time. What changes in the brain underpin these “vigilance decrements”? We designed a multiple-object monitoring (MOM) paradigm to examine how the neural representation of information varied with target frequency and time performing the task. Behavioural performance decreased over time for the rare target (monitoring) condition, but not for a frequent target (active) condition. This was mirrored in the neural results: there was weaker coding of critical information during monitoring versus active conditions. We developed new analyses that can predict behavioural errors from the neural data more than a second before they occurred. This paves the way for pre-empting behavioural errors due to lapses in attention and provides new insight into the neural correlates of vigilance decrements.


2020 ◽  
Vol 10 (9) ◽  
pp. 624 ◽  
Author(s):  
Ioana Antoaneta Georgescu ◽  
Daniela Popa ◽  
Leon Zagrean

The mediodorsal nucleus (MD) represents just one piece of a complex relay structure situated within the brain, called the thalamus. MD is characterized by its robust interconnections with other brain areas, especially with limbic-related structures. Given the close anatomo-functional relationship between the MD and the limbic system, this particular thalamic nucleus can directly influence various affective behaviors and participate in cognition. In this work, we review data collected from multiple anatomical studies conducted in rodent, human, and non-human primates, highlighting the complexity of this structure and of the neural networks in which it takes part. We provide proof that the MD is involved in the unification of several anatomical structures, being able to process the information and influence the activity in numerous cortical and subcortical neural circuits. Moreover, we uncover intrinsic and extrinsic mechanisms that offer MD the possibility to execute and control specific high functions of the nervous system. The collected data indicate the great importance of the MD in the limbic system and offer relevant insight into the organization of thalamic circuits that support MD functions.


2009 ◽  
Vol 101 (4) ◽  
pp. 1867-1875 ◽  
Author(s):  
David B. T. McMahon ◽  
Carl R. Olson

How does the brain represent a red circle? One possibility is that there is a specialized and possibly time-consuming process whereby the attributes of shape and color, carried by separate populations of neurons in low-order visual cortex, are bound together into a unitary neural representation. Another possibility is that neurons in high-order visual cortex are selective, by virtue of their bottom-up input from low-order visual areas, for particular conjunctions of shape and color. A third possibility is that they simply sum shape and color signals linearly. We tested these ideas by measuring the responses of inferotemporal cortex neurons to sets of stimuli in which two attributes—shape and color—varied independently. We find that a few neurons exhibit conjunction selectivity but that in most neurons the influences of shape and color sum linearly. Contrary to the idea of conjunction coding, few neurons respond selectively to a particular combination of shape and color. Contrary to the idea that binding requires time, conjunction signals, when present, occur as early as feature signals. We argue that neither conjunction selectivity nor a specialized feature binding process is necessary for the effective representation of shape–color combinations.


2017 ◽  
Vol 28 (2) ◽  
pp. 602-611 ◽  
Author(s):  
Charlotte Prévost ◽  
Hakwan Lau ◽  
Dean Mobbs

Abstract Surpassing negative evaluation is a recurrent theme of success stories. Yet, there is little evidence supporting the counterintuitive idea that negative evaluation might not only motivate people, but also enhance performance. To address this question, we designed a task that required participants to decide whether taking up a risky challenge after receiving positive or negative evaluations from independent judges. Participants believed that these evaluations were based on their prior performance on a related task. Results showed that negative evaluation caused a facilitation in performance. Concurrent functional magnetic resonance imaging revealed that the motivating effect of negative evaluation was represented in the insula and striatum, while the performance boost was associated with functional positive connectivity between the insula and a set of brain regions involved in goal-directed behavior and the orienting of attention. These findings provide new insight into the neural representation of negative evaluation-induced facilitation.


2018 ◽  
Author(s):  
Kshitij Dwivedi ◽  
Gemma Roig

AbstractComputational models such as deep neural networks (DNN) trained for classification are often used to explain responses of the visual cortex. However, not all the areas of the visual cortex are involved in object/scene classification. For instance, scene selective occipital place area (OPA) plays a role in mapping navigational affordances. Therefore, for explaining responses of such task-specific brain area, we investigate if a model that performs a related task can serve as a better computational model than a model that performs an unrelated task. We found that DNN trained on a task (scene-parsing) related to the function (navigational affordances) of a brain region (OPA) explains its responses better than a DNN trained on a task (scene-classification) which is not explicitly related. In a subsequent analysis, we found that the DNNs that showed high correlation with a particular brain region were trained on a task that was consistent with functions of that brain region reported in previous neuroimaging studies. Our results demonstrate that the task is paramount for selecting a computational model of a brain area. Further, explaining the responses of a brain area by a diverse set of tasks has the potential to shed some light on its functions.Author summaryAreas in the human visual cortex are specialized for specific behaviors either due to supervision and interaction with the world or due to evolution. A standard way to gain insight into the function of these brain region is to design experiments related to a particular behavior, and localize the regions showing significant relative activity corresponding to that behavior. In this work, we investigate if we can figure out the function of a brain area in visual cortex using computational vision models. From our results, we find that explaining responses of a brain region using DNNs trained on a diverse set of possible vision tasks can help us gain insights into its function. The consistency of our results using DNNs with the previous neuroimaging studies suggest that the brain region may be specialized for behavior similar to the tasks for which DNNs showed a high correlation with its responses.


2021 ◽  
Vol 44 (1) ◽  
Author(s):  
Cristopher M. Niell ◽  
Massimo Scanziani

The mouse, as a model organism to study the brain, gives us unprecedented experimental access to the mammalian cerebral cortex. By determining the cortex's cellular composition, revealing the interaction between its different components, and systematically perturbing these components, we are obtaining mechanistic insight into some of the most basic properties of cortical function. In this review, we describe recent advances in our understanding of how circuits of cortical neurons implement computations, as revealed by the study of mouse primary visual cortex. Further, we discuss how studying the mouse has broadened our understanding of the range of computations performed by visual cortex. Finally, we address how future approaches will fulfill the promise of the mouse in elucidating fundamental operations of cortex. Expected final online publication date for the Annual Review of Neuroscience, Volume 44 is July 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Hamid Karimi-Rouzbahani ◽  
Alexandra Woolgar ◽  
Anina N Rich

There are many monitoring environments, such as railway control, in which lapses of attention can have tragic consequences. Problematically, sustained monitoring for rare targets is difficult, with more misses and longer reaction times over time. What changes in the brain underpin these ‘vigilance decrements’? We designed a multiple-object monitoring (MOM) paradigm to examine how the neural representation of information varied with target frequency and time performing the task. Behavioural performance decreased over time for the rare target (monitoring) condition, but not for a frequent target (active) condition. This was mirrored in neural decoding using magnetoencephalography: coding of critical information declined more during monitoring versus active conditions along the experiment. We developed new analyses that can predict behavioural errors from the neural data more than a second before they occurred. This facilitates pre-empting behavioural errors due to lapses in attention and provides new insight into the neural correlates of vigilance decrements.


2016 ◽  
Author(s):  
Heeyoung Choo ◽  
Dirk B Walther

Humans efficiently grasp complex visual environments, making highly consistent judgments of entry-level category despite their high variability in visual appearance. How does the human brain arrive at the invariant neural representations underlying categorization of real-world environments? We here show that the neural representation of visual environments in scenes-selective human visual cortex relies on statistics of contour junctions, which provide cues for the three-dimensional arrangement of surfaces in a scene. We manipulated line drawings of real-world environments such that statistics of contour orientations or junctions were disrupted. Manipulated and intact line drawings were presented to participants in an fMRI experiment. Scene categories were decoded from neural activity patterns in the parahippocampal place area (PPA), the occipital place area (OPA) and other visual brain regions. Disruption of junctions but not orientations led to a drastic decrease in decoding accuracy in the PPA and OPA, indicating the reliance of these areas on intact junction statistics. Accuracy of decoding from early visual cortex, on the other hand, was unaffected by either image manipulation. We further show that the correlation of error patterns between decoding from the scene-selective brain areas and behavioral experiments is contingent on intact contour junctions. Finally, a searchlight analysis exposes the reliance of visually active brain regions on different sets of contour properties. Statistics of contour length and curvature dominate neural representations of scene categories in early visual areas and contour junctions in high-level scene-selective brain regions.


Author(s):  
Juliana Widyastuti Wahyuningsih Juliana Widyastuti Wahyuningsih

ABSTRAK Tidur merupakan kebutuhan yang harus terpenuhi terutama pada fase perkembangan karena selama tidur akan terjadi perkembangan otak maupun tubuh, sehingga gangguan tidur merupakan masalah yang akan menimbulkan dampak buruk terhadap pertumbuhan dan perkembangan bayi. Kualitas tidur bayi yang baik dapat diciptakan dengan memberikan pemijatan bayi secara rutin. Penelitian ini bertujuan untuk membuktikan bahwa pemijatan dapat mempengaruhi kualitas tidur bayi umur 0-3 bulan. Penelitian ini menggunakan desain penelitian Quasy Eksperimental dengan metode One Group Pretest-Postest. Sampel 22 bayi yang dipilih dengan tehnik Total Sampling yang di observasi sebelum dan sesudah diberikan pemijatan. Variabel yang diukur dalam penelitian ini adalah kualitas tidur bayi 0-3 bulan. Hasil penelitian menunjukkan bahwa ada pengaruh pijat bayi terhadap kualitas tidur bayi umur 0-3 bulan (p value  0,008 < α = 0,05).Berdasarkan hasil penelitian ini disarankan agar keluarga dan masyarakat memberikan pemijatan secara rutin dan mandiri untuk meningkatkan kebutuhan tidur bayi yang berkualitas.   ABSTRACT Sleep is a human necessity that must be met, especially in the development phase because during sleep will occur the brain and body developments, so that sleep disturbance is a problem that would cause adverse effects on infants’ growth and development. The good quality of sleep can be created by providing the infants massage routinely. This study aimed to prove that the massage could affect the quality of sleep on the 0-3 months old baby. This study used Quasy-experimental design with One Group Pretest-Posttest. The sample 22 infants selected by total sampling technique observed on before and after the massage. The variables measured in this study are the quality of sleep. The results of study indicate that there is an effect of infant massage to the sleep quality on 0-3 months old babies (p value 0,008 < α = 0,05).Based on the results of this study it recommended for the families and communities to provide infant massage regularly and independently to increase the quality of sleep on the baby.  


Healthcare ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 726
Author(s):  
Fulvia Ceccarelli ◽  
Venusia Covelli ◽  
Giulio Olivieri ◽  
Francesco Natalucci ◽  
Fabrizio Conti

Background: The COVID-19 pandemic contributes to the burden of living with different diseases, including Systemic Lupus Erythematosus (SLE). We described, from a narrative point of view, the experiences and perspectives of Italian SLE adults during the COVID-19 emergency, by distinguishing the illness experience before and after the lockdown. Methods: Fifteen patients were invited to participate. Illness narratives were collected between 22 and 29 March 2020 using a written modality to capture patients’ perspectives before and after the COVID-19 lockdown. We performed a two-fold analysis of collected data by distinguishing three narrative types and a qualitative analysis of content to identify the relevant themes and sub-themes reported. Results: Eight narratives included in the final analysis (mean length 436.9 words) have been written by eight females (mean age 43.3 ± 9.9 years, mean disease duration 13.1 ± 7.4 years). Six patients provided a quest narrative, one a chaos and the remaining one a restitution narrative. By text content analysis, we identified specific themes, temporally distinct before and after the lockdown. Before COVID-19, all the patients referred to a good control of disease, however the unexpected arrival of the COVID-19 emergency broke a balance, and patients perceived the loss of health status control, with anxiety and stress. Conclusions: We provided unique insight into the experiences of people with SLE at the time of COVID-19, underlining the perspective of patients in relation to the pandemic.


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