TY - JOUR
T1 - Age-related dedifferentiation of learning systems
T2 - An fMRI study of implicit and explicit learning
AU - Dennis, Nancy A.
AU - Cabeza, Roberto
N1 - Funding Information:
The authors wish to thank Amber Baptiste Tarter, Rakesh Arya for help in data collection and analysis; Sander Daselaar and Steve Prince for helpful comments; and Jen Bittner and Jonathan Harris for help in manuscript preparation. This work was supported by the National Institute of Health [ AG19731 and AG023770 to R.C. and T32 AG000029 to N.A.D.].
PY - 2011/12
Y1 - 2011/12
N2 - Abundant research finds that in young adults explicit learning (EL) is more dependent on the medial temporal lobes (MTL) whereas implicit learning (IL) is more dependent on the striatum. Using fMRI, we investigated age differences in each task and whether this differentiation is preserved in older adults. Results indicated that, while young recruited the MTL for EL and striatum for IL, both activations were significantly reduced in older adults. Additionally, results indicated that older adults recruited the MTL for IL, and this activation was significantly greater in older compared with young adults. A significant Task × Age interaction was found in both regions-with young preferentially recruiting the MTL for EL and striatum for IL, and older adults showing no preferential recruit for either task. Finally, young adults demonstrated significant negative correlations between activity in the striatum and MTL during both the EL and IL tasks. These correlations were attenuated in older adults. Taken together results support dedifferentiation in aging across memory systems.
AB - Abundant research finds that in young adults explicit learning (EL) is more dependent on the medial temporal lobes (MTL) whereas implicit learning (IL) is more dependent on the striatum. Using fMRI, we investigated age differences in each task and whether this differentiation is preserved in older adults. Results indicated that, while young recruited the MTL for EL and striatum for IL, both activations were significantly reduced in older adults. Additionally, results indicated that older adults recruited the MTL for IL, and this activation was significantly greater in older compared with young adults. A significant Task × Age interaction was found in both regions-with young preferentially recruiting the MTL for EL and striatum for IL, and older adults showing no preferential recruit for either task. Finally, young adults demonstrated significant negative correlations between activity in the striatum and MTL during both the EL and IL tasks. These correlations were attenuated in older adults. Taken together results support dedifferentiation in aging across memory systems.
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U2 - 10.1016/j.neurobiolaging.2010.04.004
DO - 10.1016/j.neurobiolaging.2010.04.004
M3 - Article
C2 - 20471139
AN - SCOPUS:80053623646
SN - 0197-4580
VL - 32
SP - 2318.e17-2318.e30
JO - Neurobiology of Aging
JF - Neurobiology of Aging
IS - 12
ER -