Differential hemodynamic response in affective circuitry with aging: an FMRI study of novelty, valence, and arousal.
Emerging evidence indicates that stimulus novelty is affectively potent and reliably engages the amygdala and other portions of the affective workspace in the brain. Using fMRI, we examined whether novel stimuli remain affectively salient across the lifespan, and therefore, whether novelty processing--a potentially survival-relevant function--is preserved with aging. Nineteen young and 22 older healthy adults were scanned during observing novel and familiar affective pictures while estimating their own subjectively experienced aroused levels. We investigated age-related difference of magnitude of activation, hemodynamic time course, and functional connectivity of BOLD responses in the amygdala. Although there were no age-related differences in the peak response of the amygdala to novelty, older individuals showed a narrower, sharper (i.e., "peakier") hemodynamic time course in response to novel stimuli, as well as decreased connectivity between the left amygdala and the affective areas including orbito-frontal regions. These findings have relevance for understanding age-related differences in memory and affect regulation.
Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA. ymorigu@ncnp.go.jp
Yoshiya
Y
Moriguchi
Alyson
A
Negreira
Mariann
M
Weierich
Rebecca
R
Dautoff
Bradford C
BC
Dickerson
Christopher I
CI
Wright
Lisa Feldman
LF
Barrett
D000328:Adult; D000339:Affect / Q000502:physiology*; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D000679:Amygdala / Q000098:blood supply / Q000502:physiology*; D000704:Analysis of Variance; D001143:Arousal / Q000502:physiology*; D001931:Brain Mapping; D002560:Cerebrovascular Circulation / Q000502:physiology; D004192:Discrimination, Psychological / Q000502:physiology; D005106:Exploratory Behavior / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000098:blood supply / Q000502:physiology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation; D021641:Recognition, Psychology / Q000502:physiology; D012016:Reference Values; D055815:Young Adult