Altered declarative memory in introverted middle-aged adults carrying the BDNF val66met allele

<p>Background: The val66met polymorphism of the brain-derived neurotrophic factor gene (BDNFMet) is associated with impaired learning/memory function, affective dysregulation and maladaptive personality traits. Here, we examine the potential relationship between the BDNFMet allele, introversion and declarative memory in middle-age adults.</p> <p>Methods: A total of 132 middle-aged healthy adults took part in this study that included taking a blood sample for genetic profiling, a short battery of neuropsychological tests and the NEO-Five Factor Inventory (NEO-FFI), widely used to assess the Big Five personality.</p> <p>Results: Controlling for age, level of education and sex, a multiple analysis of covariance (MANCOVA) computing the effect of BDNF polymorphism on extraversion and declarative memory revealed a significant association (<em>D</em>1,128 = 4.79; <em>p</em> = 0.03; <em>η</em>p2 = 0.053). Using the Sobel Goodman Mediation Test, it was found that 25.61% of the relationship between genotype and declarative memory performance was mediated by introversion. Subsequent correlational analyses yielded a strong and significant correlation (<em>β</em> = 0.53; <em>p</em> < 0.001) between introversion and declarative memory specific to BDNFMet individuals.</p> <p>Conclusion: this study highlights the pertinence of further investigating gene × personality × environment interactions to account for the significant variability that is observed in cognitive function in late life.</p>