Visual cortex organisation in a macaque monkey with macular degeneration

The visual field is retinotopically represented in early visual areas. It has been suggested that when adult primary visual cortex (V1) is deprived of normal retinal input it is capable of large‐scale reorganisation, with neurons inside the lesion projection zone (LPZ) being visually driven by input...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:The European journal of neuroscience 2013-11, Vol.38 (10), p.3456-3464
Hauptverfasser: Shao, Yibin, Keliris, Georgios A., Papanikolaou, Amalia, Fischer, M. Dominik, Zobor, Ditta, Jägle, Herbert, Logothetis, Nikos K., Smirnakis, Stelios M.
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:The visual field is retinotopically represented in early visual areas. It has been suggested that when adult primary visual cortex (V1) is deprived of normal retinal input it is capable of large‐scale reorganisation, with neurons inside the lesion projection zone (LPZ) being visually driven by inputs from intact retinal regions. Early functional magnetic resonance imaging (fMRI) studies in humans with macular degeneration (MD) report > 1 cm spread of activity inside the LPZ border, whereas recent results report no shift of the LPZ border. Here, we used fMRI population receptive field measurements to study, for the first time, the visual cortex organisation of one macaque monkey with MD and to compare it with normal controls. Our results showed that the border of the V1 LPZ remained stable, suggesting that the deafferented area V1 zone of the MD animal has limited capacity for reorganisation. Interestingly, the pRF size of non‐deafferented V1 voxels increased slightly (~20% on average), although this effect appears weaker than that in previous single‐unit recording reports. Area V2 also showed limited reorganisation. Remarkably, area V5/MT of the MD animal showed extensive activation compared to controls stimulated over the part of the visual field that was spared in the MD animal. Furthermore, population receptive field size distributions differed markedly in area V5/MT of the MD animal. Taken together, these results suggest that V5/MT has a higher potential for reorganisation after MD than earlier visual cortex. FMRI study on a macaque monkey with macular degeneration suggests that the border of the V1 lesion projection zone remained stable while population receptive field (pRF) size of non‐deafferented V1 increased slightly. Remarkably, V5/MT of the MD animal showed extensive activation compared to controls with pRF size distributions differing markedly. These results suggest that V5/MT has a higher potential for reorganisation after macular degeneration than earlier visual cortex.
ISSN:0953-816X
1460-9568
DOI:10.1111/ejn.12349