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  1. Article ; Online: American Bully

    Carrasco M F

    Revista Methodo, Vol 8, Iss

    importancia en el control médico de la hembra gestante

    2023  Volume 3

    Abstract: Los problemas asociados al parto son una problemática evitable sobre todo en perros con problemas anatómicos asociados al tamaño del canal de parto, por lo general esto afecta como se desenvuelve el feto previo al periodo de parición y durante el periodo ...

    Abstract Los problemas asociados al parto son una problemática evitable sobre todo en perros con problemas anatómicos asociados al tamaño del canal de parto, por lo general esto afecta como se desenvuelve el feto previo al periodo de parición y durante el periodo del inminente parto, El estrés fetal es una consecuencia al inicio del periodo de parto, si bien ayuda a terminar el desarrollo del feto y prepararlos para la parición en periodos largos se convierte en algo perjudicial para el feto. El proceso gestacional desde la detección del celo hasta la parición son parte de una serie de acciones que deben ser monitoreadas por un médico veterinario con los conocimientos adecuados para generar un buen traspaso de información sobre las circunstancias de cada caso, sobre todo en braquicéfalos que por lo general tienden a tener problemas distócicos en un alto porcentaje.
    Keywords distocia ; braquicéfalos ; cesárea ; stress fetal ; parto ; Science ; Q ; Biology (General) ; QH301-705.5
    Language Spanish
    Publishing date 2023-07-01T00:00:00Z
    Publisher Universidad Católica de Córdoba
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Task demand mediates the interaction of spatial and temporal attention.

    Palmieri, Helena / Carrasco, Marisa

    Scientific reports

    2024  Volume 14, Issue 1, Page(s) 9228

    Abstract: Psychophysical studies typically test attentional mechanisms in isolation, but in everyday life they interact to optimize human behavior. We investigated whether spatial and temporal attention interact in two orientation discrimination experiments that ... ...

    Abstract Psychophysical studies typically test attentional mechanisms in isolation, but in everyday life they interact to optimize human behavior. We investigated whether spatial and temporal attention interact in two orientation discrimination experiments that vary in task demand. We manipulated temporal and spatial attention separately and conjointly with well-established methods for testing each spatial or temporal attention. We assessed sensitivity (d') and reaction time for every combination of spatial and timing cues, each of which was valid, neutral, or invalid. Spatial attention modulated sensitivity (d') and speed (reaction time) across temporal attention conditions. Temporal attention modulated sensitivity and speed under high- but not low- task demands. Furthermore, spatial and temporal attention interacted for the high-demand task. This study reveals that task demand matters; in a simple task spatial attention suffices to improve performance, whereas in a more demanding task both spatial and temporal attention interact to boost performance, albeit in a subadditive fashion.
    MeSH term(s) Humans ; Attention/physiology ; Female ; Male ; Reaction Time/physiology ; Adult ; Space Perception/physiology ; Young Adult ; Cues ; Task Performance and Analysis
    Language English
    Publishing date 2024-04-22
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-024-58209-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Do microsaccades vary with discriminability around the visual field?

    Purokayastha, Simran / Roberts, Mariel / Carrasco, Marisa

    bioRxiv : the preprint server for biology

    2024  

    Abstract: Microsaccades-tiny fixational eye movements- improve discriminability in high acuity tasks in the foveola. To investigate whether they help compensate for low discriminability at perifovea, we examined MS characteristics relative to the adult visual ... ...

    Abstract Microsaccades-tiny fixational eye movements- improve discriminability in high acuity tasks in the foveola. To investigate whether they help compensate for low discriminability at perifovea, we examined MS characteristics relative to the adult visual performance field, which is characterized by two perceptual asymmetries: Horizontal-Vertical Anisotropy (better discrimination along the horizontal than vertical meridian), and Vertical Meridian Asymmetry (better discrimination along the lower- than upper-vertical meridian). We investigated whether and to what extent microsaccade directionality varies when stimuli are at isoeccentric locations along the cardinals under conditions of heterogeneous discriminability (Experiment 1) and homogeneous discriminability, equated by adjusting stimulus contrast (Experiment 2). Participants performed a two-alternative forced-choice orientation discrimination task. In both experiments, performance was better on trials without microsaccades between ready signal onset and stimulus offset than on trials with microsaccades. Across the trial sequence the microsaccade rate and directional pattern were similar across locations. Our results indicate that microsaccades were similar regardless of stimulus discriminability and target location, except during the response period-once the stimuli were no longer present and target location no longer uncertain-when microsaccades were biased toward the target location. Thus, this study reveals that microsaccades do not flexibly adapt as a function of varying discriminability in a basic visual task around the visual field.
    Language English
    Publishing date 2024-01-12
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2024.01.11.575288
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Featural Representation and Internal Noise Underlie the Eccentricity Effect in Contrast Sensitivity.

    Xue, Shutian / Fernández, Antonio / Carrasco, Marisa

    The Journal of neuroscience : the official journal of the Society for Neuroscience

    2024  Volume 44, Issue 3

    Abstract: Human visual performance for basic visual dimensions (e.g., contrast sensitivity and acuity) peaks at the fovea and decreases with eccentricity. The eccentricity effect is related to the larger visual cortical surface area corresponding to the fovea, but ...

    Abstract Human visual performance for basic visual dimensions (e.g., contrast sensitivity and acuity) peaks at the fovea and decreases with eccentricity. The eccentricity effect is related to the larger visual cortical surface area corresponding to the fovea, but it is unknown if differential feature tuning contributes to this eccentricity effect. Here, we investigated two system-level computations underlying the eccentricity effect: featural representation (tuning) and internal noise. Observers (both sexes) detected a Gabor embedded in filtered white noise which appeared at the fovea or one of four perifoveal locations. We used psychophysical reverse correlation to estimate the weights assigned by the visual system to a range of orientations and spatial frequencies (SFs) in noisy stimuli, which are conventionally interpreted as perceptual sensitivity to the corresponding features. We found higher sensitivity to task-relevant orientations and SFs at the fovea than that at the perifovea, and no difference in selectivity for either orientation or SF. Concurrently, we measured response consistency using a double-pass method, which allowed us to infer the level of internal noise by implementing a noisy observer model. We found lower internal noise at the fovea than that at the perifovea. Finally, individual variability in contrast sensitivity correlated with sensitivity to and selectivity for task-relevant features as well as with internal noise. Moreover, the behavioral eccentricity effect mainly reflects the foveal advantage in orientation sensitivity compared with other computations. These findings suggest that the eccentricity effect stems from a better representation of task-relevant features and lower internal noise at the fovea than that at the perifovea.
    MeSH term(s) Male ; Female ; Humans ; Contrast Sensitivity ; Orientation/physiology ; Visual Cortex/physiology ; Fovea Centralis/physiology ; Noise
    Language English
    Publishing date 2024-01-17
    Publishing country United States
    Document type Journal Article
    ZDB-ID 604637-x
    ISSN 1529-2401 ; 0270-6474
    ISSN (online) 1529-2401
    ISSN 0270-6474
    DOI 10.1523/JNEUROSCI.0743-23.2023
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  5. Article: Spatial attention alters visual cortical representation during target anticipation.

    Tünçok, Ekin / Carrasco, Marisa / Winawer, Jonathan

    bioRxiv : the preprint server for biology

    2024  

    Abstract: Attention enables us to efficiently and flexibly interact with the environment by prioritizing some image features, such as location or orientation, even before stimulus onset. We investigated how covert spatial attention affects responses in human ... ...

    Abstract Attention enables us to efficiently and flexibly interact with the environment by prioritizing some image features, such as location or orientation, even before stimulus onset. We investigated how covert spatial attention affects responses in human visual cortex prior to target onset and how it affects behavioral performance after target onset, using a concurrent psychophysics-fMRI experiment. Performance improved at cued locations and worsened at uncued locations, relative to distributed attention. BOLD responses in cortical visual field maps changed in two ways: First, there was a stimulus-independent baseline shift, positive in map locations near the cued location and negative elsewhere. Second, population receptive field centers shifted toward the attended location. Both effects increased in higher visual areas. Together, the results show that spatial attention has large effects on visual cortex prior to target appearance, altering neural response properties across the entirety of multiple visual field maps.
    Language English
    Publishing date 2024-03-07
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2024.03.02.583127
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  6. Article ; Online: When temporal attention interacts with expectation.

    Duyar, Aysun / Ren, Shiyang / Carrasco, Marisa

    Scientific reports

    2024  Volume 14, Issue 1, Page(s) 4624

    Abstract: Temporal attention is voluntarily deployed at specific moments, whereas temporal expectation is deployed according to timing probabilities. When the target appears at an expected moment in a sequence, temporal attention improves performance at the ... ...

    Abstract Temporal attention is voluntarily deployed at specific moments, whereas temporal expectation is deployed according to timing probabilities. When the target appears at an expected moment in a sequence, temporal attention improves performance at the attended moments, but the timing and the precision of the attentional window remain unknown. Here we independently and concurrently manipulated temporal attention-via behavioral relevance-and temporal expectation-via session-wise precision and trial-wise hazard rate-to investigate whether and how these mechanisms interact to improve perception. Our results reveal that temporal attention interacts with temporal expectation-the higher the precision, the stronger the attention benefit, but surprisingly this benefit decreased with delayed onset despite the increasing probability of stimulus appearance. When attention was suboptimally deployed to earlier than expected moments, it could not be reoriented to a later time point. These findings provide evidence that temporal attention and temporal expectation are different mechanisms, and highlight their interplay in optimizing visual performance.
    MeSH term(s) Motivation ; Reaction Time ; Time Perception ; Probability ; Visual Perception
    Language English
    Publishing date 2024-02-26
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-024-55399-6
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  7. Article: Adaptation and exogenous attention interact in the early visual cortex: A TMS study.

    Lee, Hsing-Hao / Fernández, Antonio / Carrasco, Marisa

    bioRxiv : the preprint server for biology

    2024  

    Abstract: Transcranial magnetic stimulation (TMS) to early visual cortex modulates the effect of adaptation and eliminates the effect of exogenous (involuntary) attention on contrast sensitivity. Here we investigated whether adaptation modulates exogenous ... ...

    Abstract Transcranial magnetic stimulation (TMS) to early visual cortex modulates the effect of adaptation and eliminates the effect of exogenous (involuntary) attention on contrast sensitivity. Here we investigated whether adaptation modulates exogenous attention under TMS to V1/V2. Observers performed an orientation discrimination task while attending to one of two stimuli, with or without adaptation. Following an attentional cue, two stimuli were presented in the stimulated region and its contralateral symmetric region. A response cue indicated the stimulus whose orientation observers had to discriminate. Without adaptation, in the distractor-stimulated condition, contrast sensitivity increased at the attended location and decreased at the unattended location via response gain-but these effects were eliminated in the target-stimulated condition. Critically, after adaptation, exogenous attention altered performance similarly in both distractor-stimulated and target-stimulated conditions. These results reveal that (1) adaptation and attention interact in the early visual cortex, and (2) adaptation shields exogenous attention from TMS effects.
    Language English
    Publishing date 2024-04-18
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2023.10.27.563093
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  8. Article ; Online: Presaccadic Attention Depends on Eye Movement Direction and Is Related to V1 Cortical Magnification.

    Hanning, Nina M / Himmelberg, Marc M / Carrasco, Marisa

    The Journal of neuroscience : the official journal of the Society for Neuroscience

    2024  Volume 44, Issue 12

    Abstract: With every saccadic eye movement, humans bring new information into their fovea to be processed with high visual acuity. Notably, perception is enhanced already before a relevant item is foveated: During saccade preparation, ...

    Abstract With every saccadic eye movement, humans bring new information into their fovea to be processed with high visual acuity. Notably, perception is enhanced already before a relevant item is foveated: During saccade preparation,
    MeSH term(s) Male ; Female ; Humans ; Eye Movements ; Saccades ; Attention/physiology ; Fovea Centralis ; Visual Perception/physiology ; Photic Stimulation
    Language English
    Publishing date 2024-03-20
    Publishing country United States
    Document type Journal Article
    ZDB-ID 604637-x
    ISSN 1529-2401 ; 0270-6474
    ISSN (online) 1529-2401
    ISSN 0270-6474
    DOI 10.1523/JNEUROSCI.1023-23.2023
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    In stock of ZB MED Cologne/Königswinter

    Zs.A 1668: Show issues Location:
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    Jg. 1995 - 2021: Lesesall (1.OG)
    ab Jg. 2022: Lesesaal (EG)

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  9. Article ; Online: How visual spatial attention alters perception.

    Carrasco, Marisa

    Cognitive processing

    2018  Volume 19, Issue Suppl 1, Page(s) 77–88

    Abstract: Visual attention is essential for visual perception. Spatial attention allows us to grant priority in processing and selectively process information at a given location. In this paper, I explain how two kinds of spatial attention: covert (allocated to ... ...

    Abstract Visual attention is essential for visual perception. Spatial attention allows us to grant priority in processing and selectively process information at a given location. In this paper, I explain how two kinds of spatial attention: covert (allocated to the target location, without accompanying eye movements) and presaccadic (allocated to the location of the upcoming saccade's target) affect performance and alter appearance. First, I highlight some behavioral and neuroimaging research on covert attention, which alters performance and appearance in many basic visual tasks. Second, I review studies showing that presaccadic attention improves performance and alters appearance at the saccade target location. Further, these modulations change the processing of feature information automatically, even when it is detrimental to the task at hand. We propose that saccade preparation may support transsaccadic integration. Systematically investigating the common and differential characteristics of covert attention and presaccadic attention will continue to further our understanding of the pervasive selective processing of information, which enables us to make sense of our complex visual world.
    MeSH term(s) Attention/physiology ; Brain/diagnostic imaging ; Brain/physiology ; Cognition/physiology ; Eye Movements/physiology ; Humans ; Neuroimaging ; Photic Stimulation/methods ; Visual Perception/physiology
    Language English
    Publishing date 2018-07-28
    Publishing country Germany
    Document type Journal Article ; Review
    ZDB-ID 2075054-7
    ISSN 1612-4790 ; 1612-4782
    ISSN (online) 1612-4790
    ISSN 1612-4782
    DOI 10.1007/s10339-018-0883-4
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  10. Article ; Online: Exogenous attention generalizes location transfer of perceptual learning in adults with amblyopia.

    Roberts, Mariel / Carrasco, Marisa

    iScience

    2022  Volume 25, Issue 3, Page(s) 103839

    Abstract: Visual perceptual learning (VPL) is a behavioral manifestation of brain neuroplasticity. However, its practical effectiveness is limited because improvements are often specific to the trained conditions and require significant time and effort. It is ... ...

    Abstract Visual perceptual learning (VPL) is a behavioral manifestation of brain neuroplasticity. However, its practical effectiveness is limited because improvements are often specific to the trained conditions and require significant time and effort. It is critical to understand the conditions that promote learning and transfer. Covert endogenous (voluntary) and exogenous (involuntary) spatial attention help overcome VPL location specificity in neurotypical adults, but whether they also do so for people with atypical visual development is unknown. This study investigates the role of exogenous attention during VPL in adults with amblyopia, an ideal population given their asymmetrically developed, but highly plastic, visual cortex. Here we show that training on a discrimination task leads to improvements in foveal contrast sensitivity, acuity, and stereoacuity. Notably, exogenous attention helps generalize learning beyond trained spatial locations. Future large-scale studies can verify the extent to which attention enhances the effectiveness of perceptual learning during rehabilitation of visual disorders.
    Language English
    Publishing date 2022-02-02
    Publishing country United States
    Document type Journal Article
    ISSN 2589-0042
    ISSN (online) 2589-0042
    DOI 10.1016/j.isci.2022.103839
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