Amyloid beta 1-42 in cerebrospinal fluid is associated with cognitive plasticity

Cerebrospinal fluid (CSF) total tau-protein (t-tau) and amyloid-beta 1-42 (Abeta1-42) have been increasingly included in the diagnostic process of Alzheimer's disease (AD). We aimed to analyze whether these CSF biomarkers correlate with cognitive plasticity as measured by a dynamic recognition test strategy. We assessed 29 elderly individuals (15 with incipient and 14 without AD) from an outpatient memory clinic at a university hospital by a Testing-the-Limits (TtL) based recognition paradigm consisting of a pre-test (baseline) and two post-test conditions with an interposed encoding instruction. We identified a negative association between Abeta1-42 and the two post-test failure rates, but not with that of the pre-test. Also, none of the standard tests correlates with Abeta 42-1 level. T-tau does not correlate with recognition performance. Our results suggest that Abeta1-42 could be useful as a state marker for cognitive plasticity.