title: Ebbinghaus revisited: influences of the BDNF Val66Met polymorphism on backward serial recall are modulated by human aging.
abstract: The brain-derived neurotrophic factor (BDNF) plays an important role in activity-dependent synaptic plasticity, which underlies learning and memory. In a sample of 948 younger and older adults, we investigated whether a common Val66Met missense polymorphism (rs6265) in the BDNF gene affects the serial position curve--a fundamental phenomenon of associative memory identified by Hermann Ebbinghaus more than a century ago. We found a BDNF polymorphism effect for backward recall in older adults only, with Met-allele carriers (i.e., individuals with reduced BDNF signaling) recalling fewer items than Val homozygotes. This effect was specific to the primacy and middle portions of the serial position curve, where intralist interference and associative demands are especially high. The poorer performance of older Met-allele carriers reflected transposition errors, whereas no genetic effect was found for omissions. These findings indicate that effects of the BDNF polymorphism on episodic memory are most likely to be observed when the associative and executive demands are high. Furthermore, the findings are in line with the hypothesis that the magnitude of genetic effects on cognition is greater when brain resources are reduced, as is the case in old age.
authors.affiliation: Max Planck Institute for Human Development, Berlin, Germany. shuchen@mpib-berlin.mpg.de
authors.forename: Shu-Chen
authors.initials: SC
authors.lastname: Li
authors.forename: Christian
authors.initials: C
authors.lastname: Chicherio
authors.forename: Lars
authors.initials: L
authors.lastname: Nyberg
authors.forename: Timo
authors.initials: T
authors.lastname: von Oertzen
authors.forename: Irene E
authors.initials: IE
authors.lastname: Nagel
authors.forename: Goran
authors.initials: G
authors.lastname: Papenberg
authors.forename: Thomas
authors.initials: T
authors.lastname: Sander
authors.forename: Hauke R
authors.initials: HR
authors.lastname: Heekeren
authors.forename: Ulman
authors.initials: U
authors.lastname: Lindenberger
authors.forename: Lars
authors.initials: L
authors.lastname: Bäckman
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000235:genetics; D000704:Analysis of Variance; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D016009:Chi-Square Distribution; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D008715:Methionine / Q000235:genetics*; D008875:Middle Aged; D009483:Neuropsychological Tests; D011110:Polymorphism, Genetic / Q000235:genetics*; D012691:Serial Learning / Q000502:physiology; D014633:Valine / Q000235:genetics*; D055815:Young Adult
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D008715:Methionine; D014633:Valine