Annual Meeting of the Society for Neuroscience edition:38 location:Washington DC, USA date:November 15-19, 2008
Since the 1980’s a huge amount of evidence has been gathered proving cortical plasticity in adult higher mammals. Prospects of using transgenic mice currently focus molecular research on this lower mammal. In our study we searched for evidence of cortical reorganisation in response to lesions in the visual system of the adult mouse. We first investigated the effect of monocular enucleation on the expression levels of zif268, an excellent neuronal activity marker, throughout the visual cortex. Analysis of these activity patterns at different survival times provided in a precise timeline in which cortical reorganisation occurs in mouse, as established based on the restoration of normal zif268 expression levels in the monocular segment of the visual cortex.
A popular explanation for this reorganisation is the take-over of the inactive part of the ipsilateral visual cortex by the non-deprived eye, yet somatosensory and auditory stimuli may drive the restoration of activity as well. To demonstrate these propositions we enucleated the remaining left eye, trimmed right side vibrissae or inactivated the right cochlea after long-term right eye deprivation. Following these deprivation experiments especially the infragranular layers of the monocular segment showed a decrease for the zif268 signal. Our data indicate that multimodal intracortical connections at least partially drive the restoration of activity after monocular deprivation in adult mouse visual cortex.