Xiaoping Fang

"Perturbation of old knowledge precedes integration of new knowledge"

The importance of overnight consolidation in integrating new knowledge has received much recent attention in the field of word learning. Less examined is the change of existing word knowledge as a result of learning, which possibly occurs even prior to the opportunity for consolidation. In the current study, participants learned new meanings for known words and novel words. Then they performed a one-back task on a list of words among which the trained words were followed by probes of new and original meanings, while EEG was recorded. Consistent with one account of complementary learning systems, familiar words related to the new meanings of preceding trained words did not show a N400 reduction compared to unrelated words. However, when preceding known words had been paired with new meanings, in contrast to being presented as exposure controls, a larger negativity (especially between 550 and 750 ms) was found for words related to the original meanings. Together, the results suggest that even before a new meaning has become integrated with a word form, meaning learning perturbs the word form’s connection with the original meaning.

Kimberly Lockwood

"Stressor-evoked interleukin-6 reactivity: What is it and why do we care?"

Why is psychological stress associated with disease risk? In this talk, I discuss one possible pathway by which psychological stress may be involved in cardiovascular disease risk. Specifically, this talk focuses on individual differences in inflammatory responses to acute psychological stress. I will present findings from two sets of analyses focused on acute stressor-evoked interleukin(IL)-6 reactivity in healthy midlife adults. In the first study, I examine whether individual differences in functional brain activity are associated with magnitude of IL-6 reactivity to acute psychological stress. In the second study, I assess sex differences in IL-6 responses and whether they are associated with C-reactive protein, a known risk factor for cardiovascular disease. Finally, I discuss implications of my findings, as well as future directions for this line of research.