Age-related reductions in human recognition memory due to impaired encoding.
The participation of the medial temporal cortex and other cerebral structures in the memory impairment that accompanies aging was examined by means of positron emission tomography. Cerebral blood flow (rCBF) was measured during encoding and recognition of faces. Young people showed increased rCBF in the right hippocampus and the left prefrontal and temporal cortices during encoding and in the right prefrontal and parietal cortex during recognition. Old people showed no significant activation in areas activated during encoding in young people but did show right prefrontal activation during recognition. Age-related impairments of memory may be due to a failure to encode the stimuli adequately, which is reflected in the lack of cortical and hippocampal activation during encoding.
Grady
C L
CL
Brain Aging and Dementia Section, National Institute on Aging, National Institutes of Health (NIH), Bethesda, MD 20892, USA.
McIntosh
A R
AR
Horwitz
B
B
Maisog
J M
JM
Ungerleider
L G
LG
Mentis
M J
MJ
Pietrini
P
P
Schapiro
M B
MB
Haxby
J V
JV
D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D002540:Cerebral Cortex / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology*; D005260:Female; D006624:Hippocampus / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology*; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology; D009778:Occipital Lobe / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology; D010296:Parietal Lobe / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology; D017397:Prefrontal Cortex / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology; D012039:Regional Blood Flow; D014055:Tomography, Emission-Computed