The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform

A Bartels - One of the best experts on this subject based on the ideXlab platform.

  • visual motion responses in the posterior Cingulate Sulcus a comparison to v5 mt and mst
    Cerebral Cortex, 2012
    Co-Authors: Elvira Fischer, H H Bulthoff, N K Logothetis, A Bartels
    Abstract:

    Motion processing regions apart from V5+/MT+ are still relatively poorly understood. Here, we used functional magnetic resonance imaging to perform a detailed functional analysis of the recently described Cingulate Sulcus visual area (CSv) in the dorsal posterior Cingulate cortex. We used distinct types of visual motion stimuli to compare CSv with V5/MT and MST, including a visual pursuit paradigm. Both V5/MT and MST preferred 3D flow over 2D planar motion, responded less yet substantially to random motion, had a strong preference for contralateral versus ipsilateral stimulation, and responded nearly equally to contralateral and to full-field stimuli. In contrast, CSv had a pronounced preference to 2D planar motion over 3D flow, did not respond to random motion, had a weak and nonsignificant lateralization that was significantly smaller than that of MST, and strongly preferred full-field over contralateral stimuli. In addition, CSv had a better capability to integrate eye movements with retinal motion compared with V5/MT and MST. CSv thus differs from V5+/MT+ by its unique preference to full-field, coherent, and planar motion cues. These results place CSv in a good position to process visual cues related to self-induced motion, in particular those associated to eye or lateral head movements.

  • Visual Motion Responses in the Posterior Cingulate Sulcus: A Comparison to V5/MT and MST
    Cerebral cortex (New York N.Y. : 1991), 2011
    Co-Authors: Elvira Fischer, H H Bulthoff, N K Logothetis, A Bartels
    Abstract:

    Motion processing regions apart from V5+/MT+ are still relatively poorly understood. Here, we used functional magnetic resonance imaging to perform a detailed functional analysis of the recently described Cingulate Sulcus visual area (CSv) in the dorsal posterior Cingulate cortex. We used distinct types of visual motion stimuli to compare CSv with V5/MT and MST, including a visual pursuit paradigm. Both V5/MT and MST preferred 3D flow over 2D planar motion, responded less yet substantially to random motion, had a strong preference for contralateral versus ipsilateral stimulation, and responded nearly equally to contralateral and to full-field stimuli. In contrast, CSv had a pronounced preference to 2D planar motion over 3D flow, did not respond to random motion, had a weak and nonsignificant lateralization that was significantly smaller than that of MST, and strongly preferred full-field over contralateral stimuli. In addition, CSv had a better capability to integrate eye movements with retinal motion compared with V5/MT and MST. CSv thus differs from V5+/MT+ by its unique preference to full-field, coherent, and planar motion cues. These results place CSv in a good position to process visual cues related to self-induced motion, in particular those associated to eye or lateral head movements.

Jean-paul Joseph - One of the best experts on this subject based on the ideXlab platform.

  • Characterization of serial order encoding in the monkey anterior Cingulate Sulcus.
    The European journal of neuroscience, 2001
    Co-Authors: Emmanuel Procyk, Jean-paul Joseph
    Abstract:

    In a previous report we showed that neurons in the Anterior Cingulate Cortex (ACC) might encode the serial order of the three components (1st, 2nd, and 3rd) of motor sequences, irrespective of which component is performed, and irrespective of the component that precedes or follows. Here we further explore these data by comparing the magnitude of cell activity at the different ranks. We also compare the activity recorded in the motor sequences and in tasks with only one motor component. We finally discuss functional hypotheses, which may account for the serial order encoding.

  • Characterization of serial order encoding in the monkey anterior Cingulate Sulcus.
    European Journal of Neuroscience, 2001
    Co-Authors: Emmanuel Procyk, Jean-paul Joseph
    Abstract:

    In a previous report we showed that neurons in the anterior Cingulate cortex might encode the serial order of the three components (first, second and third) of motor sequences, irrespective of which component is performed, and irrespective of the component that precedes or follows. Here we further explore these data by comparing the magnitude of cell activity at the different ranks. We also compare the activity recorded in the motor sequences and in tasks with only one motor component. We finally discuss functional hypotheses, which may account for the serial order encoding.

  • Anterior Cingulate activity during routine and non-routine sequential behaviors in macaques.
    Nature Neuroscience, 2000
    Co-Authors: Emmanuel Procyk, Yuji Tanaka, Jean-paul Joseph
    Abstract:

    Anterior Cingulate cortex is important in monitoring action for new challenges. We recorded neuron activity in the anterior Cingulate Sulcus of macaques while they performed a sequential problem-solving task. By trial and error, animals determined the correct sequence for touching three fixed spatial targets. After the sequence was repeated three times, we then changed the correct solution order, requiring a new search. Irrespective of component movements or their kinematics, task-related neurons encoded the serial order of the sequence. Neurons activated with sequence components (68%) differed in activity between search and repetition. Search-related activity occurred when behavioral flexibility was required and ended as soon as the animal accumulated enough information to infer the solution, but had not yet tested it. Repetition-related activity occurred in a regime of memory-based motor performance in which attention to action is less necessary.

Andrew T. Smith - One of the best experts on this subject based on the ideXlab platform.

  • Processing of Egomotion-Consistent Optic Flow in the Rhesus Macaque Cortex
    Cerebral Cortex, 2017
    Co-Authors: Benoit R. Cottereau, Andrew T. Smith, Samy Rima, Denis Fize, Yseult Héjja-brichard, Luc Renaud, Camille Lejards, Nathalie Vayssière, Yves Trotter, Jean-baptiste Durand
    Abstract:

    The cortical network that processes visual cues to self-motion was characterized with functional magnetic resonance imaging in 3 awake behaving macaques. The experimental protocol was similar to previous human studies in which the responses to a single large optic flow patch were contrasted with responses to an array of 9 similar flow patches. This distinguishes cortical regions where neurons respond to flow in their receptive fields regardless of surrounding motion from those that are sensitive to whether the overall image arises from self-motion. In all 3 animals, significant selectivity for egomotion-consistent flow was found in several areas previously associated with optic flow processing, and notably dorsal middle superior temporal area, ventral intra-parietal area, and VPS. It was also seen in areas 7a (Opt), STPm, FEFsem, FEFsac and in a region of the Cingulate Sulcus that may be homologous with human area CSv. Selectivity for egomotion-compatible flow was never total but was particularly strong in VPS and putative macaque CSv. Direct comparison of results with the equivalent human studies reveals several commonalities but also some differences.

  • vestibular inputs to human motion sensitive visual cortex
    Cerebral Cortex, 2012
    Co-Authors: Andrew T. Smith, Matthew B Wall, Kai V Thilo
    Abstract:

    Two crucial sources of information available to an organism when moving through an environment are visual and vestibular stimuli. Macaque cortical area MSTd processes visual motion, including cues to self-motion arising from optic flow and also receives information about self-motion from the vestibular system. In humans, whether human MST (hMST) receives vestibular afferents is unknown. We have combined 2 techniques, galvanic vestibular stimulation and functional MRI (fMRI), to show that hMST is strongly activated by vestibular stimulation in darkness, whereas adjacent area MT is unaffected. The activity cannot be explained in terms of somatosensory stimulation at the electrode site. Vestibular input appears to be confined to the anterior portion of hMST, suggesting that hMST as conventionally defined may contain 2 subregions. Vestibular activity was also seen in another area previously implicated in processing visual cues to self-motion, namely the Cingulate Sulcus visual area (CSv), but not in visual area V6. The results suggest that cross-modal convergence of cues to self-motion occurs in both hMST and CSv.

  • sensitivity of human visual and vestibular cortical regions to egomotion compatible visual stimulation
    Cerebral Cortex, 2010
    Co-Authors: Velia Cardin, Andrew T. Smith
    Abstract:

    The analysis and representation of visual cues to self-motion (egomotion) is primarily associated with cortical areas MST, VIP, and (recently) Cingulate Sulcus visual area (CSv). Various other areas, including visual areas V6 and V6A, and vestibular areas parietoinsular vestibular cortex (PIVC), putative area 2v (p2v), and 3aNv, are also potentially suited to processing egomotion (in some cases based on multisensory cues), but it is not known whether they are in fact involved in this process. In a functional magnetic resonance imaging (fMRI) experiment, we presented human participants with 2 types of random dot kinematograms. Both contained coherent motion but one simulated egomotion while the other did not. An area in the parieto-occipital Sulcus that may correspond to V6, PIVC, and p2v were all differentially responsive to egomotion-compatible visual stimuli, suggesting that they may be involved in encoding egomotion. More generally, we show that the use of such stimuli provides a simple and reliable fMRI localizer for human PIVC and p2v, which hitherto required galvanic or caloric stimulation to be identified.

Elvira Fischer - One of the best experts on this subject based on the ideXlab platform.

  • visual motion responses in the posterior Cingulate Sulcus a comparison to v5 mt and mst
    Cerebral Cortex, 2012
    Co-Authors: Elvira Fischer, H H Bulthoff, N K Logothetis, A Bartels
    Abstract:

    Motion processing regions apart from V5+/MT+ are still relatively poorly understood. Here, we used functional magnetic resonance imaging to perform a detailed functional analysis of the recently described Cingulate Sulcus visual area (CSv) in the dorsal posterior Cingulate cortex. We used distinct types of visual motion stimuli to compare CSv with V5/MT and MST, including a visual pursuit paradigm. Both V5/MT and MST preferred 3D flow over 2D planar motion, responded less yet substantially to random motion, had a strong preference for contralateral versus ipsilateral stimulation, and responded nearly equally to contralateral and to full-field stimuli. In contrast, CSv had a pronounced preference to 2D planar motion over 3D flow, did not respond to random motion, had a weak and nonsignificant lateralization that was significantly smaller than that of MST, and strongly preferred full-field over contralateral stimuli. In addition, CSv had a better capability to integrate eye movements with retinal motion compared with V5/MT and MST. CSv thus differs from V5+/MT+ by its unique preference to full-field, coherent, and planar motion cues. These results place CSv in a good position to process visual cues related to self-induced motion, in particular those associated to eye or lateral head movements.

  • Visual Motion Responses in the Posterior Cingulate Sulcus: A Comparison to V5/MT and MST
    Cerebral cortex (New York N.Y. : 1991), 2011
    Co-Authors: Elvira Fischer, H H Bulthoff, N K Logothetis, A Bartels
    Abstract:

    Motion processing regions apart from V5+/MT+ are still relatively poorly understood. Here, we used functional magnetic resonance imaging to perform a detailed functional analysis of the recently described Cingulate Sulcus visual area (CSv) in the dorsal posterior Cingulate cortex. We used distinct types of visual motion stimuli to compare CSv with V5/MT and MST, including a visual pursuit paradigm. Both V5/MT and MST preferred 3D flow over 2D planar motion, responded less yet substantially to random motion, had a strong preference for contralateral versus ipsilateral stimulation, and responded nearly equally to contralateral and to full-field stimuli. In contrast, CSv had a pronounced preference to 2D planar motion over 3D flow, did not respond to random motion, had a weak and nonsignificant lateralization that was significantly smaller than that of MST, and strongly preferred full-field over contralateral stimuli. In addition, CSv had a better capability to integrate eye movements with retinal motion compared with V5/MT and MST. CSv thus differs from V5+/MT+ by its unique preference to full-field, coherent, and planar motion cues. These results place CSv in a good position to process visual cues related to self-induced motion, in particular those associated to eye or lateral head movements.

Emmanuel Procyk - One of the best experts on this subject based on the ideXlab platform.

  • Characterization of serial order encoding in the monkey anterior Cingulate Sulcus.
    The European journal of neuroscience, 2001
    Co-Authors: Emmanuel Procyk, Jean-paul Joseph
    Abstract:

    In a previous report we showed that neurons in the Anterior Cingulate Cortex (ACC) might encode the serial order of the three components (1st, 2nd, and 3rd) of motor sequences, irrespective of which component is performed, and irrespective of the component that precedes or follows. Here we further explore these data by comparing the magnitude of cell activity at the different ranks. We also compare the activity recorded in the motor sequences and in tasks with only one motor component. We finally discuss functional hypotheses, which may account for the serial order encoding.

  • Characterization of serial order encoding in the monkey anterior Cingulate Sulcus.
    European Journal of Neuroscience, 2001
    Co-Authors: Emmanuel Procyk, Jean-paul Joseph
    Abstract:

    In a previous report we showed that neurons in the anterior Cingulate cortex might encode the serial order of the three components (first, second and third) of motor sequences, irrespective of which component is performed, and irrespective of the component that precedes or follows. Here we further explore these data by comparing the magnitude of cell activity at the different ranks. We also compare the activity recorded in the motor sequences and in tasks with only one motor component. We finally discuss functional hypotheses, which may account for the serial order encoding.

  • Anterior Cingulate activity during routine and non-routine sequential behaviors in macaques.
    Nature Neuroscience, 2000
    Co-Authors: Emmanuel Procyk, Yuji Tanaka, Jean-paul Joseph
    Abstract:

    Anterior Cingulate cortex is important in monitoring action for new challenges. We recorded neuron activity in the anterior Cingulate Sulcus of macaques while they performed a sequential problem-solving task. By trial and error, animals determined the correct sequence for touching three fixed spatial targets. After the sequence was repeated three times, we then changed the correct solution order, requiring a new search. Irrespective of component movements or their kinematics, task-related neurons encoded the serial order of the sequence. Neurons activated with sequence components (68%) differed in activity between search and repetition. Search-related activity occurred when behavioral flexibility was required and ended as soon as the animal accumulated enough information to infer the solution, but had not yet tested it. Repetition-related activity occurred in a regime of memory-based motor performance in which attention to action is less necessary.