PURPOSE: The Ts65Dn mouse is the most complete widely available animal model of Down syndrome (DS). Quantitative information was generated about visual function in the Ts65Dn mouse by investigating their visual capabilities by means of electroretinography (ERG) and patterned visual evoked potentials (pVEPs). METHODS: pVEPs were recorded directly from specific regions of the binocular visual cortex of anesthetized mice in response to horizontal sinusoidal gratings of different spatial frequency, contrast, and luminance generated by a specialized video card and presented on a 21-in. computer display suitably linearized by gamma correction. RESULTS: ERG assessments indicated no significant deficit in retinal physiology in Ts65Dn mice compared with euploid control mice. The Ts65Dn mice were found to exhibit deficits in luminance threshold, spatial resolution, and contrast threshold, compared with the euploid control mice. The behavioral counterparts of these parameters are luminance sensitivity, visual acuity, and the inverse of contrast sensitivity, respectively. CONCLUSIONS: DS includes various phenotypes associated with the visual system, including deficits in visual acuity, accommodation, and contrast sensitivity. The present study provides electrophysiological evidence of visual deficits in Ts65Dn mice that are similar to those reported in persons with DS. These findings strengthen the role of the Ts65Dn mouse as a model for DS. Also, given the historical assumption of integrity of the visual system in most behavioral assessments of Ts65Dn mice, such as the hidden-platform component of the Morris water maze, the visual deficits described herein may represent a significant confounding factor in the interpretation of results from such experiments.
PURPOSE: The Ts65Dnmouse is the most complete widely available animal model of Down syndrome (DS). Quantitative information was generated about visual function in the Ts65Dnmouse by investigating their visual capabilities by means of electroretinography (ERG) and patterned visual evoked potentials (pVEPs). METHODS:pVEPs were recorded directly from specific regions of the binocular visual cortex of anesthetized mice in response to horizontal sinusoidal gratings of different spatial frequency, contrast, and luminance generated by a specialized video card and presented on a 21-in. computer display suitably linearized by gamma correction. RESULTS: ERG assessments indicated no significant deficit in retinal physiology in Ts65Dnmice compared with euploid control mice. The Ts65Dnmice were found to exhibit deficits in luminance threshold, spatial resolution, and contrast threshold, compared with the euploid control mice. The behavioral counterparts of these parameters are luminance sensitivity, visual acuity, and the inverse of contrast sensitivity, respectively. CONCLUSIONS: DS includes various phenotypes associated with the visual system, including deficits in visual acuity, accommodation, and contrast sensitivity. The present study provides electrophysiological evidence of visual deficits in Ts65Dnmice that are similar to those reported in persons with DS. These findings strengthen the role of the Ts65Dnmouse as a model for DS. Also, given the historical assumption of integrity of the visual system in most behavioral assessments of Ts65Dnmice, such as the hidden-platform component of the Morris water maze, the visual deficits described herein may represent a significant confounding factor in the interpretation of results from such experiments.
Authors: J M Woodhouse; M Cregg; H L Gunter; D P Sanders; K J Saunders; V H Pakeman; M Parker; W I Fraser; P Sastry Journal: Invest Ophthalmol Vis Sci Date: 2000-08 Impact factor: 4.799
Authors: Martina Blank; Peter G Fuerst; Beth Stevens; Navid Nouri; Lowry Kirkby; Deepti Warrier; Ben A Barres; Marla B Feller; Andrew D Huberman; Robert W Burgess; Craig C Garner Journal: J Neurosci Date: 2011-04-13 Impact factor: 6.167
Authors: Tatjana Begenisic; Maria Spolidoro; Chiara Braschi; Laura Baroncelli; Marco Milanese; Gianluca Pietra; Maria E Fabbri; Giambattista Bonanno; Giovanni Cioni; Lamberto Maffei; Alessandro Sale Journal: Front Cell Neurosci Date: 2011-12-23 Impact factor: 5.505