Gender differences in cerebral metabolism for color processing in mice: A PET/MRI Study

Abstract

IntroductionColor processing is a central component of mammalian vision. Gender-related differences of color processing revealed by non-invasive functional transcranial Doppler ultrasound suggested right hemisphere pattern for blue/yellow chromatic opponency by men, and a left hemisphere pattern by women.Materials and MethodsThe present study measured the accumulation of [18F]fluorodeoxyglucose ([18F]FDG) in mouse brain using small animal positron emission tomography and magnetic resonance imaging (PET/MRI) with statistical parametric mapping (SPM) during light stimulation with blue and yellow filters compared to darkness condition.ResultsPET revealed a reverse pattern relative to dark condition compared to previous human studies: Male mice presented with left visual cortex dominance for blue through the right eye, while female mice presented with right visual cortex dominance for blue through the left eye. We applied statistical parametric mapping (SPM) to examine gender differences in activated architectonic areas within the orbital and medial prefrontal cortex and related cortical and sub-cortical areas that lead to the striatum, medial thalamus and other brain areas. The metabolic connectivity of the orbital and medial prefrontal cortex evoked by blue stimulation spread through a wide range of brain structures implicated in viscerosensory and visceromotor systems in the left intra-hemispheric regions in male, but in the right-to-left inter-hemispheric regions in female mice. Color functional ocular dominance plasticity was noted in the right eye in male mice but in the left eye in female mice.ConclusionsThis study of color processing in an animal model could be applied in the study of the role of gender differences in brain disease.

Fourier Analysis of Cerebral Metabolism of Glucose: Gender Differences in Mechanisms of Color Processing in the Ventral and Dorsal Streams in Mice

“…85e23, revised 1985) and were approved by the Institutional Animal Care and Use Committee in the state of Saxony, Germany as recommended by the responsible local animal ethics review board (Regierungspräsidium Leipzig, TVV08/13, Leipzig, Germany). The experimental setup ( Figure 1A-F) using a custom-made photostimulation device Chromatoscope in a mouse model ( Figure 1A,B) followed by small animal PET/MRI ( Figure 1C) has been described in detail elsewhere [1]. The studies were performed in isoflurane-anaesthetized animals.…”

“…The mice were placed in prone position on a special heated mouse pad with head affixed to a mouth piece ( Figure 1A). The eyes were positioned and fixed for 20 min light stimulation through the double barrel of the light source Chromatoscope ( Figure 1B) [1]. Subsequently, a whole body PET scan was started for a duration of 20 min using a preclincal scanner ( Figure 1C).…”

“…The stimulation device is a custom-made double barrel tunnel placed around both eyes and the nose ridge to separate both visual fields, and has been described in detail elsewhere [1]. Both eyes were open at all times.…”

“…There is a groove before the screen that allows insertion of filters into the right and left visual fields respectively. The stimulation procedure has been described previously [1].…”

“…Color processing as a conscious experience could serve as a model for unraveling mechanisms of color memory information processing. In a recent study, we applied conventional functional positron emission tomography and magnetic resonance imaging (f PET/MRI) technique to demonstrate gender-related cerebral metabolic changes during color processing in a mouse model [1]. However, the conventional methods have poor image resolution and could not be used to segregate the processes taking place in various parts of the visual system.…”