Spontaneous and light-induced lateralization of immediate early genes expression in domestic chicks.

Spontaneous and light-induced lateralization of immediate early genes expression in domestic chicks.
Behav Brain Res. 2019 Apr 12;:
Authors: Lorenzi E, Mayer U, Rosa-Salva O, Morandi-Raikova A, Vallortigara G
Abstract
Exposure of domestic chicks' eggs to light during embryo incubation stimulates asymmetrically the two eye-systems, reaching selectively the right eye (left hemisphere) and inducing asymmetries at the behavioral and neural level. Surprisingly, though, some types of lateralization have been observed also in dark incubated chicks, especially at the behavioral level. Here we investigate the mechanisms subtending the development of lateralization, in the presence and in the absence of embryonic light exposure. We measured the baseline level of expression for the immediate early gene product c-Fos, used as an indicator of the spontaneous level of neural activity and plasticity in four areas of the two hemispheres (preoptic area, septum, hippocampus and intermediate medial mesopallium). Additional DAPI staining measured overall cell density (regardless of c-Fos expression), ruling out any confound due to underlying asymmetries in cell density between the hemispheres. In different brain areas, c-Fos expression was lateralized either in light- (septum) or in dark-incubated chicks (preoptic area). Light exposure increased c-Fos expression in the left hemisphere, suggesting that c-Fos expression could participate to the known effe...

Source: Behavioural Brain Research - April 11, 2019 Category: Neurology Authors: Lorenzi E, Mayer U, Rosa-Salva O, Morandi-Raikova A, Vallortigara G Tags: Behav Brain Res Source Type: research