The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Eishi Asano - One of the best experts on this subject based on the ideXlab platform.
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Direct brain recordings reveal Occipital Cortex involvement in memory development.
Neuropsychologia, 2020Co-Authors: Qin Yin, Elizabeth L. Johnson, Lingfei Tang, Kurtis I. Auguste, Robert T. Knight, Eishi Asano, Noa OfenAbstract:Abstract Processing of low-level visual information shows robust developmental gains through childhood and adolescence. However, it is unknown whether low-level visual processing in the Occipital Cortex supports age-related gains in memory for complex visual stimuli. Here, we examined Occipital alpha activity during visual scene encoding in 24 children and adolescents, aged 6.2–20.5 years, who performed a subsequent memory task while undergoing electrocorticographic recording. Scenes were classified as high- or low-complexity by the number of unique object categories depicted. We found that recognition of high-complexity, but not low-complexity, scenes increased with age. Age was associated with decreased alpha power and increased instantaneous alpha frequency during the encoding of subsequently recognized high- compared to low-complexity scenes. Critically, decreased alpha power predicted improved recognition of high-complexity scenes in adolescents. These findings demonstrate how the functional maturation of the Occipital Cortex supports the development of memory for complex visual scenes.
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spontaneous and visually driven high frequency oscillations in the Occipital Cortex intracranial recording in epileptic patients
Human Brain Mapping, 2012Co-Authors: Eishi Asano, Tetsuro Nagasawa, Csaba Juhász, Robert Rothermel, Karsten Hoechstetter, Sandeep SoodAbstract:r r Abstract: High-frequency oscillations (HFOs) at � 80 Hz of nonepileptic nature spontaneously emerge from human cerebral Cortex. In 10 patients with extraOccipital lobe epilepsy, we compared the spec- tral-spatial characteristics of HFOs spontaneously arising from the nonepileptic Occipital Cortex with those of HFOs driven by a visual task as well as epileptogenic HFOs arising from the extraOccipital seizure focus. We identified spontaneous HFOs at � 80 Hz with a mean duration of 330 ms intermit- tently emerging from the Occipital Cortex during interictal slow-wave sleep. The spectral frequency band of spontaneous Occipital HFOs was similar to that of visually driven HFOs. Spontaneous Occipital HFOs were spatially sparse and confined to smaller areas, whereas visually driven HFOs involved the larger areas including the more rostral sites. Neither spectral frequency band nor amplitude of sponta- neous Occipital HFOs significantly differed from those of epileptogenic HFOs. Spontaneous Occipital HFOs were strongly locked to the phase of delta activity, but the strength of d-phase coupling decayed from 1 to 3 Hz. Conversely, epileptogenic extraOccipital HFOs were locked to the phase of delta activ- ity about equally in the range from 1 to 3 Hz. The Occipital Cortex spontaneously generates physio- logical HFOs which may stand out on electrocorticography traces as prominently as pathological HFOs arising from elsewhere; this observation should be taken into consideration during presurgical evaluation. Coupling of spontaneous delta and HFOs may increase the understanding of significance of d-oscillations during slow-wave sleep. Further studies are warranted to determine whether d-phase coupling distinguishes physiological from pathological HFOs or simply differs across anatomical loca-
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Spontaneous and visually driven high‐frequency oscillations in the Occipital Cortex: Intracranial recording in epileptic patients
Human brain mapping, 2011Co-Authors: Tetsuro Nagasawa, Csaba Juhász, Robert Rothermel, Karsten Hoechstetter, Sandeep Sood, Eishi AsanoAbstract:r r Abstract: High-frequency oscillations (HFOs) at � 80 Hz of nonepileptic nature spontaneously emerge from human cerebral Cortex. In 10 patients with extraOccipital lobe epilepsy, we compared the spec- tral-spatial characteristics of HFOs spontaneously arising from the nonepileptic Occipital Cortex with those of HFOs driven by a visual task as well as epileptogenic HFOs arising from the extraOccipital seizure focus. We identified spontaneous HFOs at � 80 Hz with a mean duration of 330 ms intermit- tently emerging from the Occipital Cortex during interictal slow-wave sleep. The spectral frequency band of spontaneous Occipital HFOs was similar to that of visually driven HFOs. Spontaneous Occipital HFOs were spatially sparse and confined to smaller areas, whereas visually driven HFOs involved the larger areas including the more rostral sites. Neither spectral frequency band nor amplitude of sponta- neous Occipital HFOs significantly differed from those of epileptogenic HFOs. Spontaneous Occipital HFOs were strongly locked to the phase of delta activity, but the strength of d-phase coupling decayed from 1 to 3 Hz. Conversely, epileptogenic extraOccipital HFOs were locked to the phase of delta activ- ity about equally in the range from 1 to 3 Hz. The Occipital Cortex spontaneously generates physio- logical HFOs which may stand out on electrocorticography traces as prominently as pathological HFOs arising from elsewhere; this observation should be taken into consideration during presurgical evaluation. Coupling of spontaneous delta and HFOs may increase the understanding of significance of d-oscillations during slow-wave sleep. Further studies are warranted to determine whether d-phase coupling distinguishes physiological from pathological HFOs or simply differs across anatomical loca-
Hanne D. Hansen - One of the best experts on this subject based on the ideXlab platform.
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Visual stimuli induce serotonin release in Occipital Cortex: A simultaneous positron emission tomography/magnetic resonance imaging study.
Human brain mapping, 2020Co-Authors: Hanne D. Hansen, Ulrich Lindberg, Brice Ozenne, Patrick M. Fisher, Annette Johansen, Claus Svarer, Sune H. Keller, Adam E Hansen, Gitte M. KnudsenAbstract:Endogenous serotonin (5-HT) release can be measured noninvasively using positron emission tomography (PET) imaging in combination with certain serotonergic radiotracers. This allows us to investigate effects of pharmacological and nonpharmacological interventions on brain 5-HT levels in living humans. Here, we study the neural responses to a visual stimulus using simultaneous PET/MRI. In a cross-over design, 11 healthy individuals were PET/MRI scanned with the 5-HT1B receptor radioligand [11 C]AZ10419369, which is sensitive to changes in endogenous 5-HT. During the last part of the scan, participants either viewed autobiographical images with positive valence (n = 11) or kept their eyes closed (n = 7). The visual stimuli increased cerebral blood flow (CBF) in the Occipital Cortex, as measured with pseudo-continuous arterial spin labeling. Simultaneously, we found decreased 5-HT1B receptor binding in the Occipital Cortex (-3.6 ± 3.6%), indicating synaptic 5-HT release. Using a linear regression model, we found that the change in 5-HT1B receptor binding was significantly negatively associated with change in CBF in the Occipital Cortex (p = .004). For the first time, we here demonstrate how cerebral 5-HT levels change in response to nonpharmacological stimuli in humans, as measured with PET. Our findings more directly support a link between 5-HT signaling and visual processing and/or visual attention.
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visual stimuli induce serotonin release in Occipital Cortex a simultaneous positron emission tomography magnetic resonance imaging study
Human Brain Mapping, 2020Co-Authors: Hanne D. Hansen, Ulrich Lindberg, Brice Ozenne, Patrick M. Fisher, Annette Johansen, Claus Svarer, Sune H. KellerAbstract:Endogenous serotonin (5-HT) release can be measured noninvasively using positron emission tomography (PET) imaging in combination with certain serotonergic radiotracers. This allows us to investigate effects of pharmacological and nonpharmacological interventions on brain 5-HT levels in living humans. Here, we study the neural responses to a visual stimulus using simultaneous PET/MRI. In a cross-over design, 11 healthy individuals were PET/MRI scanned with the 5-HT1B receptor radioligand [11 C]AZ10419369, which is sensitive to changes in endogenous 5-HT. During the last part of the scan, participants either viewed autobiographical images with positive valence (n = 11) or kept their eyes closed (n = 7). The visual stimuli increased cerebral blood flow (CBF) in the Occipital Cortex, as measured with pseudo-continuous arterial spin labeling. Simultaneously, we found decreased 5-HT1B receptor binding in the Occipital Cortex (-3.6 ± 3.6%), indicating synaptic 5-HT release. Using a linear regression model, we found that the change in 5-HT1B receptor binding was significantly negatively associated with change in CBF in the Occipital Cortex (p = .004). For the first time, we here demonstrate how cerebral 5-HT levels change in response to nonpharmacological stimuli in humans, as measured with PET. Our findings more directly support a link between 5-HT signaling and visual processing and/or visual attention.
Sune H. Keller - One of the best experts on this subject based on the ideXlab platform.
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Visual stimuli induce serotonin release in Occipital Cortex: A simultaneous positron emission tomography/magnetic resonance imaging study.
Human brain mapping, 2020Co-Authors: Hanne D. Hansen, Ulrich Lindberg, Brice Ozenne, Patrick M. Fisher, Annette Johansen, Claus Svarer, Sune H. Keller, Adam E Hansen, Gitte M. KnudsenAbstract:Endogenous serotonin (5-HT) release can be measured noninvasively using positron emission tomography (PET) imaging in combination with certain serotonergic radiotracers. This allows us to investigate effects of pharmacological and nonpharmacological interventions on brain 5-HT levels in living humans. Here, we study the neural responses to a visual stimulus using simultaneous PET/MRI. In a cross-over design, 11 healthy individuals were PET/MRI scanned with the 5-HT1B receptor radioligand [11 C]AZ10419369, which is sensitive to changes in endogenous 5-HT. During the last part of the scan, participants either viewed autobiographical images with positive valence (n = 11) or kept their eyes closed (n = 7). The visual stimuli increased cerebral blood flow (CBF) in the Occipital Cortex, as measured with pseudo-continuous arterial spin labeling. Simultaneously, we found decreased 5-HT1B receptor binding in the Occipital Cortex (-3.6 ± 3.6%), indicating synaptic 5-HT release. Using a linear regression model, we found that the change in 5-HT1B receptor binding was significantly negatively associated with change in CBF in the Occipital Cortex (p = .004). For the first time, we here demonstrate how cerebral 5-HT levels change in response to nonpharmacological stimuli in humans, as measured with PET. Our findings more directly support a link between 5-HT signaling and visual processing and/or visual attention.
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visual stimuli induce serotonin release in Occipital Cortex a simultaneous positron emission tomography magnetic resonance imaging study
Human Brain Mapping, 2020Co-Authors: Hanne D. Hansen, Ulrich Lindberg, Brice Ozenne, Patrick M. Fisher, Annette Johansen, Claus Svarer, Sune H. KellerAbstract:Endogenous serotonin (5-HT) release can be measured noninvasively using positron emission tomography (PET) imaging in combination with certain serotonergic radiotracers. This allows us to investigate effects of pharmacological and nonpharmacological interventions on brain 5-HT levels in living humans. Here, we study the neural responses to a visual stimulus using simultaneous PET/MRI. In a cross-over design, 11 healthy individuals were PET/MRI scanned with the 5-HT1B receptor radioligand [11 C]AZ10419369, which is sensitive to changes in endogenous 5-HT. During the last part of the scan, participants either viewed autobiographical images with positive valence (n = 11) or kept their eyes closed (n = 7). The visual stimuli increased cerebral blood flow (CBF) in the Occipital Cortex, as measured with pseudo-continuous arterial spin labeling. Simultaneously, we found decreased 5-HT1B receptor binding in the Occipital Cortex (-3.6 ± 3.6%), indicating synaptic 5-HT release. Using a linear regression model, we found that the change in 5-HT1B receptor binding was significantly negatively associated with change in CBF in the Occipital Cortex (p = .004). For the first time, we here demonstrate how cerebral 5-HT levels change in response to nonpharmacological stimuli in humans, as measured with PET. Our findings more directly support a link between 5-HT signaling and visual processing and/or visual attention.
Brice Ozenne - One of the best experts on this subject based on the ideXlab platform.
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Visual stimuli induce serotonin release in Occipital Cortex: A simultaneous positron emission tomography/magnetic resonance imaging study.
Human brain mapping, 2020Co-Authors: Hanne D. Hansen, Ulrich Lindberg, Brice Ozenne, Patrick M. Fisher, Annette Johansen, Claus Svarer, Sune H. Keller, Adam E Hansen, Gitte M. KnudsenAbstract:Endogenous serotonin (5-HT) release can be measured noninvasively using positron emission tomography (PET) imaging in combination with certain serotonergic radiotracers. This allows us to investigate effects of pharmacological and nonpharmacological interventions on brain 5-HT levels in living humans. Here, we study the neural responses to a visual stimulus using simultaneous PET/MRI. In a cross-over design, 11 healthy individuals were PET/MRI scanned with the 5-HT1B receptor radioligand [11 C]AZ10419369, which is sensitive to changes in endogenous 5-HT. During the last part of the scan, participants either viewed autobiographical images with positive valence (n = 11) or kept their eyes closed (n = 7). The visual stimuli increased cerebral blood flow (CBF) in the Occipital Cortex, as measured with pseudo-continuous arterial spin labeling. Simultaneously, we found decreased 5-HT1B receptor binding in the Occipital Cortex (-3.6 ± 3.6%), indicating synaptic 5-HT release. Using a linear regression model, we found that the change in 5-HT1B receptor binding was significantly negatively associated with change in CBF in the Occipital Cortex (p = .004). For the first time, we here demonstrate how cerebral 5-HT levels change in response to nonpharmacological stimuli in humans, as measured with PET. Our findings more directly support a link between 5-HT signaling and visual processing and/or visual attention.
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visual stimuli induce serotonin release in Occipital Cortex a simultaneous positron emission tomography magnetic resonance imaging study
Human Brain Mapping, 2020Co-Authors: Hanne D. Hansen, Ulrich Lindberg, Brice Ozenne, Patrick M. Fisher, Annette Johansen, Claus Svarer, Sune H. KellerAbstract:Endogenous serotonin (5-HT) release can be measured noninvasively using positron emission tomography (PET) imaging in combination with certain serotonergic radiotracers. This allows us to investigate effects of pharmacological and nonpharmacological interventions on brain 5-HT levels in living humans. Here, we study the neural responses to a visual stimulus using simultaneous PET/MRI. In a cross-over design, 11 healthy individuals were PET/MRI scanned with the 5-HT1B receptor radioligand [11 C]AZ10419369, which is sensitive to changes in endogenous 5-HT. During the last part of the scan, participants either viewed autobiographical images with positive valence (n = 11) or kept their eyes closed (n = 7). The visual stimuli increased cerebral blood flow (CBF) in the Occipital Cortex, as measured with pseudo-continuous arterial spin labeling. Simultaneously, we found decreased 5-HT1B receptor binding in the Occipital Cortex (-3.6 ± 3.6%), indicating synaptic 5-HT release. Using a linear regression model, we found that the change in 5-HT1B receptor binding was significantly negatively associated with change in CBF in the Occipital Cortex (p = .004). For the first time, we here demonstrate how cerebral 5-HT levels change in response to nonpharmacological stimuli in humans, as measured with PET. Our findings more directly support a link between 5-HT signaling and visual processing and/or visual attention.
Annette Johansen - One of the best experts on this subject based on the ideXlab platform.
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Visual stimuli induce serotonin release in Occipital Cortex: A simultaneous positron emission tomography/magnetic resonance imaging study.
Human brain mapping, 2020Co-Authors: Hanne D. Hansen, Ulrich Lindberg, Brice Ozenne, Patrick M. Fisher, Annette Johansen, Claus Svarer, Sune H. Keller, Adam E Hansen, Gitte M. KnudsenAbstract:Endogenous serotonin (5-HT) release can be measured noninvasively using positron emission tomography (PET) imaging in combination with certain serotonergic radiotracers. This allows us to investigate effects of pharmacological and nonpharmacological interventions on brain 5-HT levels in living humans. Here, we study the neural responses to a visual stimulus using simultaneous PET/MRI. In a cross-over design, 11 healthy individuals were PET/MRI scanned with the 5-HT1B receptor radioligand [11 C]AZ10419369, which is sensitive to changes in endogenous 5-HT. During the last part of the scan, participants either viewed autobiographical images with positive valence (n = 11) or kept their eyes closed (n = 7). The visual stimuli increased cerebral blood flow (CBF) in the Occipital Cortex, as measured with pseudo-continuous arterial spin labeling. Simultaneously, we found decreased 5-HT1B receptor binding in the Occipital Cortex (-3.6 ± 3.6%), indicating synaptic 5-HT release. Using a linear regression model, we found that the change in 5-HT1B receptor binding was significantly negatively associated with change in CBF in the Occipital Cortex (p = .004). For the first time, we here demonstrate how cerebral 5-HT levels change in response to nonpharmacological stimuli in humans, as measured with PET. Our findings more directly support a link between 5-HT signaling and visual processing and/or visual attention.
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visual stimuli induce serotonin release in Occipital Cortex a simultaneous positron emission tomography magnetic resonance imaging study
Human Brain Mapping, 2020Co-Authors: Hanne D. Hansen, Ulrich Lindberg, Brice Ozenne, Patrick M. Fisher, Annette Johansen, Claus Svarer, Sune H. KellerAbstract:Endogenous serotonin (5-HT) release can be measured noninvasively using positron emission tomography (PET) imaging in combination with certain serotonergic radiotracers. This allows us to investigate effects of pharmacological and nonpharmacological interventions on brain 5-HT levels in living humans. Here, we study the neural responses to a visual stimulus using simultaneous PET/MRI. In a cross-over design, 11 healthy individuals were PET/MRI scanned with the 5-HT1B receptor radioligand [11 C]AZ10419369, which is sensitive to changes in endogenous 5-HT. During the last part of the scan, participants either viewed autobiographical images with positive valence (n = 11) or kept their eyes closed (n = 7). The visual stimuli increased cerebral blood flow (CBF) in the Occipital Cortex, as measured with pseudo-continuous arterial spin labeling. Simultaneously, we found decreased 5-HT1B receptor binding in the Occipital Cortex (-3.6 ± 3.6%), indicating synaptic 5-HT release. Using a linear regression model, we found that the change in 5-HT1B receptor binding was significantly negatively associated with change in CBF in the Occipital Cortex (p = .004). For the first time, we here demonstrate how cerebral 5-HT levels change in response to nonpharmacological stimuli in humans, as measured with PET. Our findings more directly support a link between 5-HT signaling and visual processing and/or visual attention.
