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193. Neural mechanisms of spatial- and feature-based attention: A quantitative analysis
e80
Society Proceedings / Clinical Neurophysiology 120 (2009) e9–e88
tional torque pulses. Therefore, deeper parts of the muscle can be additionally mobilized with FMS in the case of paraplegics. Acknowledgement This work Foundation.
was
supported
by
the
Else-Kröner-Fresenius
doi:10.1016/j.clinph.2008.07.190
193. Neural mechanisms of spatial- and feature-based attention: A quantitative analysis—C. Stoppel 1, C.N. Böhler 2, C. Sabelhaus 1,2, H.-J. Heinze 1,2, J.M. Hopf 1,2, M.A. Schoenfeld 1,2 (1 Ottovon-Guericke Universität, Klinik für Neurologie II, Magdeburg, Germany, 2 Leibniz-Institut für Neurobiologie, Magdeburg, Germany)
Methods: We used functional magnetic resonance imaging (fMRI) to study the influence of gonadal steroid hormones (estradiol and progesterone) on the activated neural networks and on interhemispheric connectivity during a verbal task. Normally cycling, healthy women without hormonal contraceptives were examined three times during the menstrual cycle: during menses (1–3 day), during the follicular phase (9–11 day) and during the luteal phase (21–23 day). They were scanned while they performed a simple word comparison task. Results: We identified a left lateralized activation pattern in frontal cortex during menses. During the follicular phase, activations were bilateral. During the luteal phase, activations were still bilateral but much more pronounced than during the other cycle phases. Using a PPI analysis, we identified regions showing a significant correlation with the time course of activation in the maximum of the left hemispheric activation cluster. We could delineate significant differences in the negative correlation of left and right hemispheric activation between menses and the follicular phase. Conclusions: Our study shows that female subjects exhibit a changing activation pattern during a verbal task across the menstrual cycle. Activations are most pronounced during the luteal phase, where progesterone level is at its maximum. Further we could identify significant changes in interhemispheric connectivity between menses and the follicular phase with high levels of estradiol. The negative correlation between the left and the right hemispheric frontal activations is most pronounced during menses. This might indicate that during menses the inhibition exerted from the dominant on the non dominant hemisphere is strongest, while this inhibition is reduced during the follicular phase. This finding could explain the reduced functional asymmetries found with increased levels of sex hormones.
Attentional selection can be based on the spatial locations, nonspatial stimulus features, or entire objects as integrated feature ensembles. Several studies reported attentional modulations in those regions that process the constituent features of the presented stimuli. Here we employed the functional magnetic resonance imaging (fMRI) to directly compare the magnitude of space- and/or feature-based attentional modulations while subjects directed their attention to a particular color (red or green) of a transparent surface and at the same time to a spatial location (left or right visual field). The experimental design made it possible to disentangle and quantify the hemodynamic activity elicited by identical physical stimuli when attention was directed to spatial locations and/or stimulus features. The highest modulations were observed when the attentional selection was based on spatial location. Attended features also elicited a response increase relative to unattended features when their spatial location was attended. Importantly, at unattended locations, a response increase upon feature-based selection was observed in motion-sensitive but not in color-related areas. This suggests that compared to color, motion stimuli are more effective in capturing attention at unattended locations leading to a competitive advantage. These results support the idea of a high biological relevance of the feature motion in the visual world.
Halpern DF. Sex, brains, hands, and spatial cognition. Develop Rev 1996;16:261–70. Hausmann M, Güntürkün O. Sex dierences in functional cerebral asymmetries in a repeated measures design. Brain Cogn 1999;41:263–75. McCourt ME, Mark VW, Radonovich KJ, Willison SK, Freeman P. The eects of gender, menstrual phase and practice on the perceived location of the midsagittal plane. Neuropsychologia 1997;35:717–24. Sanders G, Wenmoth D. Verbal and music dichotic listening tasks reveal variations in functional cerebral asymmetry across the menstrual cycle that are phase and task dependent. Neuropsychologia 1998;36:869–74.
doi:10.1016/j.clinph.2008.07.191
doi:10.1016/j.clinph.2008.07.192
194. Sex hormones affect interhemispheric connectivity during the menstrual cycle: An fMRI study—S. Weis 1, B. Stoffers 1, M. Hausmann 2, W. Sturm 1 (1 Universitätsklinikum Aachen, Neurologie - Klinische Neuropsychologie, Aachen, Germany, 2 Durham University, Department of Psychology, Durham, UK)
195. Differential diagnostic value of eye movement recording in PSP-Parkinsonism, Richardson’s syndrome, and idiopathic Parkinson’s disease—E.H. Pinkhardt 1, R. Jürgens 2, W. Becker 2, F. Valdarno 2, A.C. Ludolph 1, J. Kassubek 1 (1 Universitätsklinikum Ulm, Abteilung Neurologie, Ulm, Germany, 2 Universitätsklinikum Ulm, Abteilung Neurologie, Sektion Neurophysiologie, Ulm, Germany)
Introduction: Sex differences in a number of cognitive abilities are well documented. Although performances of both genders overlap to a large degree, women tend to outperform men in many aspects of verbal ability, while men tend to outperform women in spatial tasks (Halpern, 1996). It has repeatedly been shown that functional asymmetries are more pronounced in men, while they are less developed in women (e.g. Hausmann and Güntürkün, 1999). Furthermore, the lateralization of cognitive functions in women fluctuates during the menstrual cycle (e.g. McCourt et al., 1997; Sanders and Wenmoth, 1998). Thus, sex hormones seem to play a major role in generating and preserving cerebral asymmetries. We assume that an increase in sex hormone level reduces the interhemispheric transfer and interhemispheric inhibition and thus diminishes functional asymmetries.
References
Objectives: Vertical gaze palsy is a highly relevant clinical sign in Parkinsonian syndromes. As the eponymous feature it is one of the core features in the diagnosis of progressive supranuclear palsy (PSP). Recent studies have suggested a further differentiation of PSP in Richardson’s Syndrome (RS) and PSP-Parkinsonism (PSP-P). The aim of this study was to search for oculomotor abnormalities in the PSP-P subset out of a sample of PSP patients and to compare these findings with those of RS patients, patients with Idiopathic Parkinson’s disease (IPD) and a control group. Materials and methods: Twelve cases of RS, five cases of PSP-P and 27 cases of IPD were examined by using video-oculography (VOG) and compared to 39 healthy controls. Additionally, a clinical
Society Proceedings / Clinical Neurophysiology 120 (2009) e9–e88
tional torque pulses. Therefore, deeper parts of the muscle can be additionally mobilized with FMS in the case of paraplegics. Acknowledgement This work Foundation.
was
supported
by
the
Else-Kröner-Fresenius
doi:10.1016/j.clinph.2008.07.190
193. Neural mechanisms of spatial- and feature-based attention: A quantitative analysis—C. Stoppel 1, C.N. Böhler 2, C. Sabelhaus 1,2, H.-J. Heinze 1,2, J.M. Hopf 1,2, M.A. Schoenfeld 1,2 (1 Ottovon-Guericke Universität, Klinik für Neurologie II, Magdeburg, Germany, 2 Leibniz-Institut für Neurobiologie, Magdeburg, Germany)
Methods: We used functional magnetic resonance imaging (fMRI) to study the influence of gonadal steroid hormones (estradiol and progesterone) on the activated neural networks and on interhemispheric connectivity during a verbal task. Normally cycling, healthy women without hormonal contraceptives were examined three times during the menstrual cycle: during menses (1–3 day), during the follicular phase (9–11 day) and during the luteal phase (21–23 day). They were scanned while they performed a simple word comparison task. Results: We identified a left lateralized activation pattern in frontal cortex during menses. During the follicular phase, activations were bilateral. During the luteal phase, activations were still bilateral but much more pronounced than during the other cycle phases. Using a PPI analysis, we identified regions showing a significant correlation with the time course of activation in the maximum of the left hemispheric activation cluster. We could delineate significant differences in the negative correlation of left and right hemispheric activation between menses and the follicular phase. Conclusions: Our study shows that female subjects exhibit a changing activation pattern during a verbal task across the menstrual cycle. Activations are most pronounced during the luteal phase, where progesterone level is at its maximum. Further we could identify significant changes in interhemispheric connectivity between menses and the follicular phase with high levels of estradiol. The negative correlation between the left and the right hemispheric frontal activations is most pronounced during menses. This might indicate that during menses the inhibition exerted from the dominant on the non dominant hemisphere is strongest, while this inhibition is reduced during the follicular phase. This finding could explain the reduced functional asymmetries found with increased levels of sex hormones.
Attentional selection can be based on the spatial locations, nonspatial stimulus features, or entire objects as integrated feature ensembles. Several studies reported attentional modulations in those regions that process the constituent features of the presented stimuli. Here we employed the functional magnetic resonance imaging (fMRI) to directly compare the magnitude of space- and/or feature-based attentional modulations while subjects directed their attention to a particular color (red or green) of a transparent surface and at the same time to a spatial location (left or right visual field). The experimental design made it possible to disentangle and quantify the hemodynamic activity elicited by identical physical stimuli when attention was directed to spatial locations and/or stimulus features. The highest modulations were observed when the attentional selection was based on spatial location. Attended features also elicited a response increase relative to unattended features when their spatial location was attended. Importantly, at unattended locations, a response increase upon feature-based selection was observed in motion-sensitive but not in color-related areas. This suggests that compared to color, motion stimuli are more effective in capturing attention at unattended locations leading to a competitive advantage. These results support the idea of a high biological relevance of the feature motion in the visual world.
Halpern DF. Sex, brains, hands, and spatial cognition. Develop Rev 1996;16:261–70. Hausmann M, Güntürkün O. Sex dierences in functional cerebral asymmetries in a repeated measures design. Brain Cogn 1999;41:263–75. McCourt ME, Mark VW, Radonovich KJ, Willison SK, Freeman P. The eects of gender, menstrual phase and practice on the perceived location of the midsagittal plane. Neuropsychologia 1997;35:717–24. Sanders G, Wenmoth D. Verbal and music dichotic listening tasks reveal variations in functional cerebral asymmetry across the menstrual cycle that are phase and task dependent. Neuropsychologia 1998;36:869–74.
doi:10.1016/j.clinph.2008.07.191
doi:10.1016/j.clinph.2008.07.192
194. Sex hormones affect interhemispheric connectivity during the menstrual cycle: An fMRI study—S. Weis 1, B. Stoffers 1, M. Hausmann 2, W. Sturm 1 (1 Universitätsklinikum Aachen, Neurologie - Klinische Neuropsychologie, Aachen, Germany, 2 Durham University, Department of Psychology, Durham, UK)
195. Differential diagnostic value of eye movement recording in PSP-Parkinsonism, Richardson’s syndrome, and idiopathic Parkinson’s disease—E.H. Pinkhardt 1, R. Jürgens 2, W. Becker 2, F. Valdarno 2, A.C. Ludolph 1, J. Kassubek 1 (1 Universitätsklinikum Ulm, Abteilung Neurologie, Ulm, Germany, 2 Universitätsklinikum Ulm, Abteilung Neurologie, Sektion Neurophysiologie, Ulm, Germany)
Introduction: Sex differences in a number of cognitive abilities are well documented. Although performances of both genders overlap to a large degree, women tend to outperform men in many aspects of verbal ability, while men tend to outperform women in spatial tasks (Halpern, 1996). It has repeatedly been shown that functional asymmetries are more pronounced in men, while they are less developed in women (e.g. Hausmann and Güntürkün, 1999). Furthermore, the lateralization of cognitive functions in women fluctuates during the menstrual cycle (e.g. McCourt et al., 1997; Sanders and Wenmoth, 1998). Thus, sex hormones seem to play a major role in generating and preserving cerebral asymmetries. We assume that an increase in sex hormone level reduces the interhemispheric transfer and interhemispheric inhibition and thus diminishes functional asymmetries.
References
Objectives: Vertical gaze palsy is a highly relevant clinical sign in Parkinsonian syndromes. As the eponymous feature it is one of the core features in the diagnosis of progressive supranuclear palsy (PSP). Recent studies have suggested a further differentiation of PSP in Richardson’s Syndrome (RS) and PSP-Parkinsonism (PSP-P). The aim of this study was to search for oculomotor abnormalities in the PSP-P subset out of a sample of PSP patients and to compare these findings with those of RS patients, patients with Idiopathic Parkinson’s disease (IPD) and a control group. Materials and methods: Twelve cases of RS, five cases of PSP-P and 27 cases of IPD were examined by using video-oculography (VOG) and compared to 39 healthy controls. Additionally, a clinical