Age-dependent differences in human brain activity using a face- and location-matching task: An fMRI study

Purpose: To evaluate the differences of cortical activation
patterns in young and elderly healthy subjects for object and
spatial visual processing using a face- and location-matching task.
Materials and Methods: We performed a face- and a location-matching
task in 15 young (mean age: 28 +/- 9 years) and 19 elderly (mean
age: 71 +/- 6 years) subjects. Each experiment consisted of 7
blocks alternating between activation and control condition. For
face matching, the subjects had to indicate whether two displayed
faces were identical or different. For location matching, the
subjects had to press a button whenever two objects had an
identical position. For control condition, we used a perception
task with abstract images. Functional imaging was performed on a
1.5-tesla scanner using an EPI sequence. Results: In the
face-matching task, the young subjects showed bilateral (right 1
left) activation in the occipito-temporal pathway (occipital gyrus,
inferior and middle temporal gyrus). Predominantly right
hemispheric activations were found in the fusiform gyrus, the right
dorsolateral prefrontal cortex (inferior and middle frontal gyrus)
and the superior parietal gyrus. In the elderly subjects, the
activated areas in the right fronto-lateral cortex increased. An
additional activated area could be found in the medial frontal
gyrus (right > left). In the location-matching task, young
subjects presented increased bilateral (right > left) activation
in the superior parietal lobe and precuneus compared with face
matching. The activations in the occipito-temporal pathway, in the
right fronto-lateral cortex and the fusiform gyrus were similar to
the activations found in the face-matching task. In the elderly
subjects, we detected similar activation patterns compared to the
young subjects with additional activations in the medial frontal
gyrus. Conclusion: Activation patterns for object-based and spatial
visual processing were established in the young and elderly healthy
subjects. Differences between the elderly and young subjects could
be evaluated, especially by using a face-matching task. Copyright
(c) 2007 S. Karger AG, Basel.