TY - JOUR
T1 - Origins of individual differences in episodic memory in the oldest-old
T2 - A population-based study of identical and same-sex fraternal twins aged 80 and older
AU - Johansson, Boo
AU - Whitfield, Keith
AU - Pedersen, Nancy L.
AU - Hofer, Scott M.
AU - Ahern, Frank
AU - McClearn, Gerald E.
PY - 1999/5
Y1 - 1999/5
N2 - The relative importance of genetic and environmental influences on episodic memory in very late life was studied using a quantitative genetic approach. Identical (n = 125) and same-sex fraternal (n = 157) twin pairs, aged 80 and older (mean age = 83.3; SD = 3.1) and without a diagnosis of dementia were tested with seven memory measures: (1-2) Digit Span Forward and Backwards, (3) Prose Recall, (4) Thurstone's picture memory test, and the Memory in Reality (MIR) test, including the subtasks of (5) free recall, (6) recognition, and (7) relocation. Heritabilities, estimated by structural equation modeling, ranged from .04 to .49. The digit span backward test showed the highest heritability (h2 = .49), while heritabilities were typically lower for the long-term memory measures. The results demonstrate genetic influences on memory in the oldest-old, but suggest that the magnitude of these effects differs across memory measures.
AB - The relative importance of genetic and environmental influences on episodic memory in very late life was studied using a quantitative genetic approach. Identical (n = 125) and same-sex fraternal (n = 157) twin pairs, aged 80 and older (mean age = 83.3; SD = 3.1) and without a diagnosis of dementia were tested with seven memory measures: (1-2) Digit Span Forward and Backwards, (3) Prose Recall, (4) Thurstone's picture memory test, and the Memory in Reality (MIR) test, including the subtasks of (5) free recall, (6) recognition, and (7) relocation. Heritabilities, estimated by structural equation modeling, ranged from .04 to .49. The digit span backward test showed the highest heritability (h2 = .49), while heritabilities were typically lower for the long-term memory measures. The results demonstrate genetic influences on memory in the oldest-old, but suggest that the magnitude of these effects differs across memory measures.
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U2 - 10.1093/geronb/54B.3.P173
DO - 10.1093/geronb/54B.3.P173
M3 - Article
C2 - 10363039
AN - SCOPUS:0033067468
SN - 1079-5014
VL - 54
SP - P173-P179
JO - Journals of Gerontology - Series B Psychological Sciences and Social Sciences
JF - Journals of Gerontology - Series B Psychological Sciences and Social Sciences
IS - 3
ER -