Age-related differences of neural connectivity during mental rotation.

The purpose of the present study was to investigate age-related effects on functional brain networks during a mental rotation task. At behavioral level age-related cognitive deficits have been shown. Cognitive deficits in older adults are associated with structural decline, especially in frontal and parietal areas and in the corpus callosum. In consequence, functional networks are affected by old age as well. To this end, a graph theoretical approach was taken, which quantifies the global and local efficiency as well as the cost efficiency of frontal and parietal intrahemispheric and interhemispheric networks. Main results indicate that intrahemispheric and interhemispheric networks are differently affected by older age: in the left frontal and the left and right parietal intrahemispheric networks global and local efficiency was reduced, whereas in frontal and parietal interhemispheric networks cost efficiency was decreased.