Löwel, Siegrid

[["dc.bibliographiccitation.firstpage","2801"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","European Journal of Neuroscience"],["dc.bibliographiccitation.lastpage","2811"],["dc.bibliographiccitation.volume","36"],["dc.contributor.author","Yeritsyan, Naira"],["dc.contributor.author","Lehmann, Konrad"],["dc.contributor.author","Puk, Oliver"],["dc.contributor.author","Graw, Jochen"],["dc.contributor.author","Loewel, Siegrid"],["dc.date.accessioned","2018-11-07T09:06:24Z"],["dc.date.available","2018-11-07T09:06:24Z"],["dc.date.issued","2012"],["dc.description.abstract","By combining behavioural analyses with intrinsic signal optical imaging, we analysed visual performance and visual cortical activity in the albino mouse strain BALB/c, which is increasingly being used as an animal model of neuropsychological disorders. Visual acuity, as measured by a virtual-reality optomotor system, was 0.12 cycles per degree (cyc/deg) in BALB/c mice and 0.39 cyc/deg in pigmented C57BL/6 mice. Surprisingly, BALB/c mice showed reflexive head movements against the direction of the rotating stimulus. Contrast sensitivity was significantly lower in BALB/c mice (45% contrast at 0.064 cyc/deg) than in C57BL/6 mice (6% contrast). In the visual water task, visual acuity was 0.3 cyc/deg in BALB/c mice and 0.59 cyc/deg in C57BL/6 mice. Thus, the visual performance of BALB/c mice was significantly impaired in both behavioural tests visual acuity was similar to 0.3 cyc/deg lower than in C57BL/6 mice, and contrast sensitivity was reduced by a factor of similar to 8. In BALB/c mice, visual cortical maps induced by stimulation of the contralateral eye were normal in both activation strength and retinotopic map quality. In contrast, maps induced by ipsilateral eye stimulation differed significantly between the strains activity in a region representing 15 degrees to 19 degrees elevation in the visual field was significantly weaker in BALB/c mice than in C57BL/6 mice. Taken together, our observations show that BALB/c mice, like the albino animals of other species, have a significantly lower visual performance than C57BL/6 mice and a modified cortical representation of the ipsilateral eye that may impair stereopsis. Thus, our results caution against disregarding vision as a confounding factor in behavioural tests of neuropsychological disorders."],["dc.identifier.doi","10.1111/j.1460-9568.2012.08195.x"],["dc.identifier.isi","000308941000009"],["dc.identifier.pmid","22738127"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/25548"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","0953-816X"],["dc.title","Visual capabilities and cortical maps in BALB/c mice"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e11912"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","PloS one"],["dc.bibliographiccitation.lastpage","e11912"],["dc.bibliographiccitation.volume","5"],["dc.contributor.author","Keary, Nina"],["dc.contributor.author","Voss, Joe"],["dc.contributor.author","Lehmann, Konrad"],["dc.contributor.author","Bischof, Hans-Joachim"],["dc.contributor.author","Löwel, Siegrid"],["dc.date.accessioned","2019-07-09T11:53:19Z"],["dc.date.available","2019-07-09T11:53:19Z"],["dc.date.issued","2010"],["dc.description.abstract","BACKGROUND: The primary visual cortex of mammals is characterised by a retinotopic representation of the visual field. It has therefore been speculated that the visual wulst, the avian homologue of the visual cortex, also contains such a retinotopic map. We examined this for the first time by optical imaging of intrinsic signals in zebra finches, a small songbird with laterally placed eyes. In addition to the visual wulst, we visualised the retinotopic map of the optic tectum which is homologue to the superior colliculus in mammals. METHODOLOGY/PRINCIPAL FINDINGS: For the optic tectum, our results confirmed previous accounts of topography based on anatomical studies and conventional electrophysiology. Within the visual wulst, the retinotopy revealed by our experiments has not been illustrated convincingly before. The frontal part of the visual field (0 degrees +/-30 degrees azimuth) was not represented in the retinotopic map. The visual field from 30 degrees -60 degrees azimuth showed stronger magnification compared with more lateral regions. Only stimuli within elevations between about 20 degrees and 40 degrees above the horizon elicited neuronal activation. Activation from other elevations was masked by activation of the preferred region. Most interestingly, we observed more than one retinotopic representation of visual space within the visual wulst, which indicates that the avian wulst, like the visual cortex in mammals, may show some compartmentation parallel to the surface in addition to its layered structure. CONCLUSION/SIGNIFICANCE: Our results show the applicability of the optical imaging method also for small songbirds. We obtained a more detailed picture of retinotopic maps in birds, especially on the functional neuronal organisation of the visual wulst. Our findings support the notion of homology of visual wulst and visual cortex by showing that there is a functional correspondence between the two areas but also raise questions based on considerable differences between avian and mammalian retinotopic representations."],["dc.identifier.doi","10.1371/journal.pone.0011912"],["dc.identifier.fs","582119"],["dc.identifier.pmid","20694137"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/7274"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60396"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1932-6203"],["dc.rights","Goescholar"],["dc.rights.uri","https://goescholar.uni-goettingen.de/licenses"],["dc.subject.mesh","Animals"],["dc.subject.mesh","Female"],["dc.subject.mesh","Male"],["dc.subject.mesh","Molecular Imaging"],["dc.subject.mesh","Optical Processes"],["dc.subject.mesh","Photic Stimulation"],["dc.subject.mesh","Songbirds"],["dc.subject.mesh","Superior Colliculi"],["dc.subject.mesh","Visual Cortex"],["dc.title","Optical imaging of retinotopic maps in a small songbird, the zebra finch."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]